Exotic Aquatic Organisms in Asia

Transcription

1 Exotic Aquatic Organisms in Asia Proceedings of a Workshop on Introduction of Exotic Aquatic Organisms in Asia Edited by SENA S.DE SILVA / Asian Fisheries Society Special Publication No. 3 ARCHIV 283 trifs AIDAB i.j'ii LI CANADA

2 r Exotic Aquatic Organisms in Asia Edited by S.S. De Silva 1989 Published by the Asian Fisheries Society in association with the International Development Research Centre of Canada and the Australian International Development Assistance Bureau

3 Exotic Aquatic Organisms in Asia Proceedings of a Workshop on Introduction of Exotic Aquatic Organisms in Asia Edited by S.S Di SILVA 1989 Printèdin Manila, Philippines. Dc Silva, S.S., editor Exotic aquatic organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, is4 p. Asian Fisheries Society, Manila, Philippines. Copyright, 1989, Asian Fisheries Society, Philippines, and International Development Research Centre, Canada. Cover by: Ovidio Espiritu, Jr. ISBN

4 Contents Foreword Introduction Presidential Address Dr. Chua Thia Eng, President Asian Fisheries Society Address by the Chairman of the Workshop Dr. Sena S. De Silva v vi vii ix Exotics - A Global Perspective with Special Reference to Finfish Introductions to Asia S.S.DeSilva Impacts of Introduced and Translocated Freshwater Fishes in Australia 7 A.H. Art hington Exotic and Translocated Freshwater Fishes in Australia 21 Ri. McKay The Status of the Exotic Aquatic Organisms in China 35 Tan Yo-Jun and Tong He-Yi Impact of Exotic Aquatic Species in Indian Waters 45 H.P.C. Shez'ty, M.C. Nandeesha anda.g. Jhingran Exotic Aquatic Species Introduction into Indonesia 57 H. Muhammad Eidman Present Status of Aquatic Organisms Introduced into Japan 63 K. Chiba, V. Taki, K. Sakai and Y. Qozeki The Status of Introduced Fish Species in Malaysia 71 K.J. Ang, R. Gopinath and T.E. Chua II'

5 The Introduction of Exotic Aquatic Species in the Philippines 83 R.O. Juliano, R. Guerrero III and I. Ronquillo Introduction of Exotic Aquatic Species in Singapore 91 L.M. Chou and T.J. Lam Status of Introduced Species in Sri Lanka 99 S.S. De Silva Exotic Aquatic Species in Taiwan 101 I-Chiu Liao and Hsi-Chiang Liu Exotic Aquatic Species in Thailand 119 T. Piyakarnchana Australian Government Position: Introduction of Exotic Aquatic Species 125 F.B. Michaelis Recommendations of the Workshop 133 List of Participants 136 Appendices Definition of Exotics 139 Assessment of the Impact of Major Food Fish Species Introduced into Some of the Asian Countries 141 Ill. Instances of Decline/Appearance of Indigenous Species as a Possible Consequence of Introduced Fish Species 150 Ornamental Fishes 152 Existing Legislation or Code of Practices Adopted by Individual Countries in Respect of Introducing Aquatic Species 153 iv

6 Foreword Introductions of exotic aquatic organisms have been going on worldwide for centuries. Asia, for one, has long been engaged in importations from Africa and Europe. It has likewise been an active center which has exported endemic species to other parts of the globe. Because of the increasing problems brought about by indiscriminate transfers of 'potential' species from one country to another, various national governments made steps to regulate such activities. The Code of Practice to reduce risks of introductions initially framed by the International Council for the Exploration of the Sea (ICES) was a vital step indicating worldwide concern on the effects of uncontrolled species introductions. The European Inland Fisheries Advisory Commission (EIFAC) in 1982 then organized a symposium on "Stock Enhancement in the Management of Freshwater Fisheries" and visualized an International Code of Practice for Europe. Rigid regulatory control measures were then patterned after these and employed by many developed countries. Unfortunately, the lack of strict regulatory measures in developing countries has resulted in indiscriminate introductions, some of which remain unrecorded to this day. The Workshop on the Introduction of Exotic Aquatic Organisms in Asia organized by the Asian Fisheries Society in June 19-21, 1988 in Darwin, Australia, was an initial effort of fisheries scientists in the region towards regulating exotic species introductions into Asia. We appreciate the active participation of these scientists during the workshop and the Society is grateful to the Australian International Development Assistance Bureau (AIDAB) and the International Development Research Centre (IDRC) of Canada for the funding support which contributed to the smooth and successful conduct of the workshop. It is hoped that the issues and recommendations raised in this workshop shall complement existing efforts of national governments and the Food and Agricultural Organization of the United Nations (FAQ) in developing an applicable code of ethics in the regulation of future introductions in Asia. CHUA THIA-ENG President Asian Fisheries Society V

7 Introduction This special publication of the Asian Fisheries Society, in conjunction with the International Development Research Centre (Canada) and the Australian International Development Assistance Bureau comprises the Proceedings of the Workshop on Exotic Aquatic Introductions into Asia, held in Darwin, Australia in June It is inevitable that all countries in the region cannot be covered in a small Workshop, primarily due to financial limitations. However, it is hoped that these Proceedings will create a revitalization of interest in the region on the role of exotic species and help to address the question more scientifically and objectively when future introductions are considered. These Proceedings should be considered as the first of a set of documentations on this complex issue, and therefore should not be considered as a complete review. I am thankful to Mr. Jay Maclean, Secretary, Asian Fisheries Society, and Ms. Elsie Tech, Executive Secretary of the Society for their help in the editing. The editing was clone mostly when I was on an attachment to the Department of Zoology, National University of Singapore, and I am grateful to Prof. T.J. Lam, and the NUS for giving me this opportunity. Sena S. De Silva vi

8 Address of Dr. Chua Thia-Eng President of the Asian Fisheries Society It is a pleasure and honour for me to address this important workshop on "Introduction of Exotic Species in Asia". The Asian Fisheries Society is indeed grateful to all those who have helped to make this workshop possible, especially to the Government of the Northern Territory, Australia, for hosting this workshop, the Australian International Development Assistance Bureau (AIDAB) for travel support, the International Development Research Centre (IDRC) for pre-workshop preparations and publication of workshop proceedings and other national agencies that helped to bring many of our scientists to this gathering. The contribution of these international and national agencies speaks for the importance of the subject matter that we will be discussing in the next couple of days. The issue on exotic species transfer is of international concern pertaining to the high risk of introduction of diseases, disruptive effects on aquatic communities and environment as well as the genetical degradation of host stocks. Not withstanding the above, introduction of exotic species between countries will continue to occur as it has already been doing so in the past 3 decades, closely associated with aquaculture development, the increase of aquarium fish trade and inland water body management. Asia is one of the world's active centers involved in movement of fish from one nation to another for decades without any effective regulatory control. Thus, the African cichlid, Oreochromis mossambicus, abounds in most water bodies in Asia. Since its introduction the golden snail (Ampullaria cyprinas) into the Philippines has become a nuisance to rice cultivation. The water hyacinth (Eichhornia crassipes) from South America has become a problematic aquatic macrophyte, blocking waterways in lakes, rivers and choking fish ponds. Introduced species have beneficial effects, too, especially in economic gain, to countries which badly require foreign exchange earnings and a cheap fish protein supply. In fact, many of the Chinese and Indian carps introduced into various nations in Asia have played a significant role in increasing national aquaculture production. Exotic species introduction is often initiated by fishery professionals who are either ignorant or unconcerned of the risks involved as well as by commercial enterprises in the aquarium trade. In most countries of Asia, there are sufficient legislative measures to control importation of undesirable species. However, the inability to effectively implement legislative requirements has given rise to easy entry of exotic species in the region. Public awareness and strict implementation of regulatory measures in North America have helped in curbing unregulated introductions. The establishment of mechanisms governing the introduction of exotic species through international agreements like the "Code of practice to reduce the risks of adverse effects arising from the introduction of non-indigenous species" adopted by the International Council for the Exploration of the Sea (ICES) and the European Inland Fisheries Advisory Commission (ETFAC) represent the regional efforts in Europe. In Asia, the Indo-Pacific Fisheries Council (IPFC) has expressed concern over past and present introductions but places emphasis on the collection and exchange of information. Regulatory measures are left to individual country's legislation. The main purpose of this workshop is to objectively review the impacts of species transfer in Asia taking into consideration the meager socioeconomic conditions of Asian nations and to explore appropriate measures by which exotic species introduction can be best regulated. One immediate impact of this workshop is a greater concern of fishery professionals like us who can vii

9 help to promote national awareness of the issue and help develop appropriate strategies to minimize the adverse effects of exotic species transfer. In closing, I wish to thank the local secretariat, in particular Director Darryl Grey, for his excellent local arrangements and time and effort put into the preparation of this workshop. Thank you.

10 Address by the Chairman of the Workshop We of the Asian Fisheries Society are grateful to the Australian International Development Assistance Bureau for making this workshop possible. I consider it a deep honour to be invited to Chair this workshop and wish to express my gratitude to my fellow Councillors for bestowing this privilege and take this opportunity to welcome all the participants to this workshop. In keeping with one of the main objectives of the Asian Fisheries Society, to address key issues pertaining to fisheries in the region, the Council at its Second Meeting in 1984 unanimously decided that the Introduction of Aquatic Organisms into the region needed careful consideration. We were aware that this issue was also being addressed by some international organizations amongst others, and the American Fisheries Society. In spite of these considerations the Society felt a need to consider this issue; complex as it is from an Asian context where the the socio-economic factors cannot be ignored and or separated from the fisheries issues in general. Initially, four Objectives for the Workshop were identified: address the issue of aquatic introductions in the region, evaluate the pros and cons of introductions hitherto made in the region, develop guidelines/a code of ethics for future introductions, and issue a policy statement on future introductions. It is unlikely that we would be able to fulfill our objectives within the next three days. I consider this workshop as the first step in the direction of achieving our objectives. In order to do so we will have to address our minds to a few key points: Do we have sufficient information/knowledge of the situation in each of the countries in the region - if so how do we proceed to collect this information, especially that in the 'grey literature' Do we need to develop protocols for consideration by Governments in the region, and if so what criteria should we use: should they take into account the socioeconomic factors, etc. Are there recent examples from the region introductions that impel us to think afresh? or elsewhere on proposed Undoubtedly all of us would agree that we should not adopt, clause to clause, what has been recommended as suitable for Northern America, Europe and or for that matter mainland Australia. This is not because we want to be different but such a course of action would be self defeating. If we were to do the former there would not have been a need to come to this lovely city, Darwin. Equally, we have a lot to gain from their experiences. ix

11 Conditions in Europe and North America are not comparable to that of ours ir the region. Here, I do not mean in a climatological sense but in the context of the numbe: of species involved, complexity of the habitats, heterogeneity of the flora and fauna, anl the gross beneficial effects of some introductions that have contributed to the animal protein supply. Some of the socio-economic benefits of introductions are not totally quantifiable but they certainly cannot and should not be ignored. Ladies and Gentlemen with these few remarks, which I hope would help us to focus at some of our deliberations, I wish to commence the proceedings. We should all bear in mind that the deliberations of the next three days will direct the Society's future course of actioa in dealing with this very complex issue. Finally, it is my duty to express our gratitude and appreciation to the local organizers Mr. Darryl Grey and his team, for their excellent arrangements. Thank you. Sena S. De Silva x

12 Exotics - A Global Perspective with Special Reference to Finfish Introductions to Asia SENA S. DE SILVA Departments of Fisheries Biology and Zoology University of Ruhuna Matara, Sri Lanka De Silva, S.S Exotics - a global perspective with special reference to finfish introductions to Asia, p In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. The need for a fresh evaluation of the definition of 'exotics' is pointed out. The global transfer of finfish species is summarized. Those species which have been transferred across all five continents are considered as 'global' and number 15, of which six have originated from Asia. Recent controversies on introductions are briefly pointed out and the need for detailed scientific evaluation prior to deciding on an introduction, based on recent recommendations from Asia, is focused on. Asia in general, has suffered comparatively limited damage as a result of introductions. In particular the number of native species lost or endangered in the region and directly attributable to an exotic is scanty. Exotic(s) and introduction(s) are terms used synonymously to define the transfer of live organisms from one country to another. With respect to aquatic organisms more refined definitions have been attempted: for example, that by Shafland and Lewis(1984). These authors defined an exotic as an organism whose entire range is outside the country to which it is introduced. In essence all definitions encompass into them, the concept of country boundaries. If one were to extend this further an introduction of a species between some of the Indonesian islands, even across the accepted zoogeographical boundaries such as Wallace's or Weber's lines, would not be tantamount to an introduction and the species transferred will not be classified as an exotic: this reference is not hypothetical. In essence the political boundaries, which have no real biological basis or validity should not be the criterion for defining an exotic and or an introduction but the zoogeographical boundaries of the organisms. In the context of an acceptance of the above definition a revision of the status of introductions in the world, and in Asia in particular is needed. Inland Fish Species Transfers - Global Status The global status of the international transfers upto 1981 was reviewed by Welcomme (1981). A summary of the transfers made globally, is given in Table 1. A total of 168 finfish species belonging to 33 families have been introduced either deliberately or accidentally out of their natural distribution range. In this analysis the traditional geographical boundaries were 1

13 2 taken as the basis for the introductions. This number is less than that reported later by Welconime (1984) when he observed that 163 species have moved to 120 countries of which 42% have established successfully. The two major families which have been subjected to such transfers beyond their natural range are the Cichlidae and the Cyprinidae, of which 36 and 37 species have been transferred from their natural ranges respectively. Transfers across all continents which could be considered as global introductions number only 15 species. Of these six have originated from Asia and are all Cyprinids - primarily the Chinese and Indian major carps. A total of 35 species have been transferred from Asia and 22 into Asia, of which 6 have been introduced into Oceania. According to Jhingran and Gopalakrishnan (1974) however, 24 species have been introduced into Southeast Asia. The reasons for the introduction/transfer of fish as well as other aquatic organisms beyond their normal range of distribution are many. Welcomme (1981) recognized three clear phases and reasons for introduction with respect to freshwater fish; Phase I Phase II period equivalent to the Middle Ages in Europe - diffusion of a limited number of species throughout Europe and Asia. middle of the nineteenth century to about for sport and for sentimental reasons e.g., the spread of Salmonids from Europe into Asia, and Phase III : 1940 to date - for aquaculture and ornamental trade e.g., the spread of Chinese and Indian major carps. In the recent years the question of introductions/transfers across countries has been receiving increasing attention, in particular piscine introductions. The status of introductions into America and Oceania were considered in detail by Courtenay and Stauffer (1984) and included a protocol for evaluating proposed exotic fish introductions into the United States. In Europe, the question was addressed by the European Inland Fisheries Advisory Commission (EIPAC) of the Food and Agriculture Organization, and five specific protocols were evolved for the inspection of molluscs, crustaceans, marine fish, salmonid fish and molluscan hatcheries (EIFAC/CECPI 1984). An attempt was also made to develop an international policy for the reduction of risks and adverse effects arising from introductions. To meet this end it was felt that two levels of documentation were necessary. A code of Practice - a general guideline and statement of policy which can supplement local legislation, and Protocols - oriented check lists for implementation of the code of pracl;ice. In the development of an international policy and a code of practice for effecting introductions one has to take into consideration the sentiments expressed by neighbouring countries, even if they are widely separated. It is in this perspective that Coates (1987) dealt with the introductions into Papua New Guinea.

14 3 Table 1. Summary of introductions of fish species in the world (derived from Welcomme 1981). Columns ito 5 in order are, number of species introduced into region beyond its native distribution range; global introductions where the species has been introduced into at least 4 continents; introduced from Asia; introduced into Asia and inter-asian introductions. As-refers to originating from Asia; 'Oc' refers to Oceania. Family ACIPENSERIDAE ANABANTIDAE ANGUILUDAE ATHERIMDAE BAGRIDAE CENTRARCHIDAE CENTROPOMIDAE CHANNIDAE CHANTDAE CICHLIDAE CLARIIDAE CLUPEIDAE COBITIDAE COREGONTDAE CYPRJMDAE CYPRINODONTIDAE ELEOTRIDAE ERYTHRINIDAE ESOCIDAE GOBIIDAE ICTALURIDAE LORICARIIDAE ORYZIATIDAE OSMERIDAE OSPHRONEMIDAE OSTEOGLOSSIDAE PERCICHTHYIDAE PERCIDAE POECILIDAE SALMONTDAE SCIAENTDAE SILURTDAE UMBRIDAE I As ;20c i;20c 1;lOc 3:lOc 1: loc 1 12 Controversies When compared to the information available on finfish that on other aquatic organisms is scanty. Hitherto there had been no attempts to document such introductions either globally or regionally, even though very detrimental effects have been recorded with respect to some. A case in point is the introduction of the water fern Salvinia into Asia, which has had the most negative impact brought about by an exotic animal or plant (Bhukaswan 1980). On the other hand, with respect to finfish species the status of individual introductions have been assessed and views on their beneficial or harmful effects remain controversial. In this controversy Oreochromis mossambicus (Peters), the aquatic chicken of the 1960's (Ling 1977) is now considered a nuisance species, globally (Welcomme 1984) except perhaps in Sri Lanka (De Silva 1985; 1987) and in Papua New Guinea (West and Glucksman 1967; Coates 1985). Of course in hind sight one could suggest that the results could have been better if O.niloticus was introduced. During the 50's and early 60's O.niloticus was relatively unknown and O.mossambicus was the choice species. In these countries this species remains the backbone of an important artisanal fishery and therefore a source of protein for the poor, and there are no reports on environmental degradation caused by this species. Comparable controversies exist

15 4 with respect to other introductions. For example the introduction of Lates niloticus into Lake Victoria was hailed as a disaster by some (Barel et al. 1985; Payne 1987) but its introduction into Lake Kioga is considered as a success; as much as that of Limnothrissa miodon into Lakes Kivu and Kariba (Eccles 1985). A similar debate exists with respect to the introduction of Sarotherodon aureus into Lake Kinneret (Gophen et al. 1983). The above examples point out that the lack of specific criteria and/or adoption of different standards in the assessment of the role of an exotic, and focus on the need to establish criteria for evaluating the impact of an exotic. The evolution of such a scheme for the evaltation of the impact of exotics will not have a direct bearing on the introductions made hithcrto but will permit the adoption of a more rational and an objective approach for envisaged introductions. The system or scale that is to be devised should not only take into consideration the biological and ecological impact of the introductions but an equal weightage should also be given to the sociological impact. Sociological impact is not an easily quantifiable parameter. In the present context it would mean whether the introductions have resulted in a significant contribution to the protein supply to the poorer people in an area and/or whether a significant number of job opportunities have been created or lost as a result of the introduction and the like. Reported detrimental effects as a result of piscine introductions into Asia, apart from the numerous parasites associated with the introductions, are rare and far apart; it has never reached the controversial stage as for example that associated with the Lates niloticus introduction into Lake Victoria in Africa (Bare! et al. 1985; Payne 1987). However, in Asia aso the near extinction of the endemic small goby, sinarapan, Mistichthys luzonensis (Smith) from Lake Buhi is partly attributed to the introduction of 0. mossambicus (Baluyut 1983). Similarly the introduction of two gobiids into Lake Lanao is supposed to have influenced its native cyprinid flock consisting of about 20 species of Barbus (Frey 1969). Asia has a paucity of lakes. Hence, there is an equivalent paucity of species flocks comparable to those of the African Great Lakes. In this context all efforts must be made to preserve this minuscule number of spec es flocks in Asia. The global parasitic introductions associated with the piscine introductions have been reviewed by Hoffman and Schubert (1984). Asia contributed its share to the rest of the continents and likewise received its share from elsewhere. It remains a miracl that these accidental introductions have not reached epidemic levels, except in very rare and isolated instances. Even human pathogens are involved; for example, Schistosoma mansoni was transferred to Hong Kong in in infected snails from South America (Biophalaria straminea) contaminated with imported water plants for aquaria (Meier-Brook 1975). All fish trematodes and cestodes require intermediate hosts; digenean trematodes a molluscan host, and cestodes one or more intermediate hosts. As a result of these requirements the chances of relocation of parasitic species and their spreading are limited. In spite of these requirements some parasites have been transferred. A case in point is the inter-continental and intra-asian relocation of the cestode Bothriocephalus opsarichthydis (=B. go wkengensis) associated with the introduction of grass carp, initially from the Amur river stocks and later from elsewhere.

16 5 Decision for Effecting Introductions Very often decisions and or recommendations for introductions are made with a view to increasing the yield but on relatively meagre and often on less than adequate scientific knowledge. Turner (1982) advocated the introduction of zooplanktivorous clupeid Limnothrissa miodon into Lake Malai because he considered it to be a more efficient zooplankton predator than cyprinids and or other zooplanktivores found in Lake Malai. This view has been contested (Eccies 1985; McKaye et al. 1985). Eccles (1985) has attempted to show that Turner's conclusions were based on temperate examples and comparisons of lakes with wide differences in morphometry, climatic and chemical factors. Eccles (1985) pointed out that rehabilitation (social) of the existing fishery could be more cost effective and unlikely to have any deleterious effects on the lake and will result in an equally higher yield. In Asia, Soemarwoto and Costa-Pierce (1987) recommended the introduction of the clupeid Corica goniognathous from Thailand to fill the supposedly vacant pelagic, zooplankton feeding niche in the Jatilnuhur reservoir in the Indonesian island of Java. Later it transpired that the species referred to is Clupeichthys aesarnensis (Costa-Pierce 1988) and that this species is endemic to the Mekong system. This goes to show that enthusiasm and emotions seem to override scientific knowledge, which could be detrimental to the fishery as well as flora and fauna in the future. The two instances cited here also lead to the broad question of utilization of introductions to fill vacant niches in lacustrine waters. Admittedly, there are instances where such introductions as in the case of Lake Kariba, have been overtly successful. Asia has a paucity of natural lakes and consequently a poor lacustrine fish fauna (Fernando and Holcik 1982). There is increasing evidence that these artificial, lacustrine bodies get colonized by suitable indigenous riverine species such as by the freshwater clupeid in the case of Ubolratna in Thailand (Costa-Pierce 1988) and by indigenous cyprinids in the case of reservoirs in Sri Lanka (De Silva and Sirisena 1987), which could support profitable fisheries. It is apparent that at present most introductions are done with care and lot of scrutiny; but can we be satisfied? As pointed out by Pillay (1977) the era of haphazard and unplanned introductions is hopefully over. However, it is important to take into account that there has been a general degradation of the quality and quantity of the natural habitats of most aquatic organisms and more so of those species endemic to a particular region - an unavoidable consequence of development and human population growth. It is therefore, important to take such indirect factors also into account when planning aquatic introductions; should or should not the need for conservation of native species and fisheries be weighed against the development benefits of improved fish stocks? It is in this context that it would be desirable to develop a code of practice for aquatic introductions into Asia and not adopt those evolved elsewhere in their entireity. References Baluyut, E.A Stocking and introduction of fish in lakes and reservoirs in the ASEAN countries. FAQ Fisheries Technical Paper 236: 82p. Barel, C.D.N. et al Destruction of Fisheries in Africa's lakes. Nature 315 (2): Bhukaswan, T Management of Asian reservoirs fisheries. FAQ Fisheries TechnicalPaper 207, 69 p. Coates, D Fish yield estimates for the Sepik river, Papua, New Guinea, alarge flood plain system east of "Wallace's line. Journal of Fish Biology 27: Coates, D Consideration of fish introductions to the Sepik River, Papua New Guinea. Aquaculture and Fisheries Management 19:

17 6 Costa-Pierce, B Study mission to Northeast Thailand for assessment of a pelagic freshwater sardine Cu1peihhys aesarnen.ris. IOEIICLARM, 63 p. (mimeo). Courtenay, W.R. and LR. Stauffer Distribution, biology and management of exotic fishes. John Hopkins University, Baltimore, 430 p. De Silva, S.S Status of the introduced cichlid Sarotherodon mossambicis (Peters) in the reservoir fishery of Sri Larka: a management strategy and ecological implications. Aquaculture and Fisheries Management 16: De Silva, S.S Impact of exotics on the inland fishery resources of Sri Lanka. Arch iv fur Hydrobiologie beihft, Ergebni:;se der Limnologie 28: De Silva, S.S. and H.K.G. Sirisena New fish resources of reservoirs in Sri Lanka: Feasibility of introductions of a subsidiary gill net fishery for minor cyprinids. Fisheries Research 6: Eccles, D.H Lake flies and sardines - a cautionary note. Biological Conservation 33: EIFAC/CECPI Report of the EIFAC working party on stock enhancement, EIFAC Technical Paper 44: 22 p. Femando, C.H. and J. Holcik The nature of fish communities: a factor influencing the fishery potential of tropical lakes and reservoirs. Hydrobiologia 97: Frey, D.G A limnological reconnaissance of Lake Lanao, Verhein Intemational Verhein Theoretical Agnew Limnologie 15: Gophen, M., R.W. Drenner and G.L. Vinyard Cichlid stocking and the decline of the Galilee Saint Peter's fish (Sarothe -odon galilaeus) in Lake Kinneret, Israel, Canadian Journal of Fisheries and Aquatic Science 40: Hofman, G.L. and G. Schubert Some parasites of exotic fishes, p In W.R. Courtenay and R. Stauffer (eds.) Distribution, biology and management of exotic fishes. John Hopkins University, Baltimore. Jhingran, V.C. and V. Gopalakrishnan Catalogue of cultivated aquatic organisms. FAO Technical Paper, 130, 83 p. Ling, SW Aquaculture in Southeast Asia. A historical overview. Washington Sea Grant Publication, 108 p. McKay, K.R., R.D. Makwinja, W.M. Menyani and O.K. Mhone On the possible introduction of non-indigenous zooplankton-fishes into Lake Malawi, Africa, Biological Conservation 33: Meier-Brook, C A snail intemiediate host Schutosoma mansoni introduced to Hong Kong. WHO/SCHISTO/85: 37 p. Payne, I A Lake perched on piscine peril. New Scientist 1575: Pillay, T.V.R Planning of aquaculture development. Fishing News (Books) Ltd., Surrey, England, 71 p. Shafland, P.L. and W.M. Lewis Terminology associated with introduced organisms. Fisheries 9: Soemarwotto, 0. and B. Costa-Pierce (undated). Importation of a pelagic freshwater sardine, Corica goniognathus to IndoneSian reservoirs for fisheries enhancement (mimeoed document). Tumer, J.L Lake flies, water fleas and sardines. FAO Technical Report 1: Welcomme, R.L Register of international transfers of inland fish species. FAO Fisheries Technical Paper 213: 120 p. Welcomme, R.L International transfers of inland fish species, p In W.R. Courtenay and J.R. Stauffer (eds.) Dütribution, Biology and management of Exotic Species. The John Hopkins University Press, Baltimore. West, G.J. and J. Glucksman Introduction and distribution of exotic fish in Papua New Guinea. Papua New Guinea Agricultural Journal 27:

18 Impacts of Introduced and Translocated Freshwater Fishes in Australia A.H. ARTHINGTON Center for Catchment and In-st ream Research Division of Australian Environmental Studies Griffith University Nathan, Queensland 4111 Australia Arthington, A.H Impacts of introduced and translocated freshwater fishes in Australia, p In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. Australian inland waters have been successfully colonised by 19 freshwater species introduced to the continent, including 5 salmonids, a percid, 5 cyprinids, 6 poediiids and 3 cichlids. Some of these introductions have been beneficial but the aim of this chapter is to review the ecological consequences of fish introductions, both planned and unintentional, in temis of possible adverse impacts on freshwater biota and ecosystems. Such impacts may include hybridisation between species, sub-species and genetic strains, habitat and Water quality alterations, competition, predation and the introduction of parasites and diseases. An account of the translocation of four endemic Australian fishes into Lake Eacham, Queensland is also included because these translocations appear to have caused the extinction of the endemic rainbowfish unique to the lake, chiefly as a result of predation. Conspicuous gaps in knowledge of introduced species in Australia and research priorities are highlighted. The final section outlines areas of ecological theory that may assist in predicting the impacts of species introductions, i.e., the theosy of island biogeography, the concept of limiting similarity and the analysis of food webs. Australian inland waters have been successfully colonized by 19 freshwater fish species introduced to the continent, including 5 salmonids, a percid, 4 cyprinids, 6 poeciliids and 3 cichlids (Table 1). There is also some slender evidence that reproducing populations of two other species occur in Australian waters. The Jack Dempsey cichlid, Cichiasoma octofasciatum (Regan), is quite abundant in the cooling pondage of Hazeiwood power station near Morwell, Victoria (Cadwallader et al. 1980) but it is not certain that this species breeds there. The weather bach, Mis gurnus anguillicaudatus, has also been reported to breed in Australian waters (McKay, pers. comm.). Several recent reviews have summarized the origins and distribution of introduced species in Australia, their effects on aquatic ecosystems, especially impacts on endemic fish species, and management problems (see Pollard et al. 1980; Tilzey 1980; McKay 1978; Arthington et al. 1983; McKay 1984; Arthington 1986; Arthington and Mitchell 1986; Fletcher 1986; Lloyd et al. 1986; Arthington and Lloyd, in press). Full details of introductions and translocations of species in Australia are summarized by McKay (this volume) and the distributions of four species are shown in Figs. 1 and 2. The objectives of this review are to draw attention to the ecological consequences of species introductions, both planned and unintentional. Most of the paper deals with introduced species but an account of the translocation of four endemic Australian fishes into Lake Eacham, Queensland is also included (Fig. 1), because these translocations appear to have caused the 7

19 8 extinction of the endemic rainbow fish unique to this lake, chiefly as a result of predation (see Barlow et al. 1987). This striking example of the ecological consequences of ndemic fish translocations was first described by McKay (1987). Throughout the review, conspicuous gaps in knowledge of introduced species. in Australia and research priorities are highlighted, concluding with an overview of current ecological theories that may assist in predicting the consequences of species introductions, and thus provide the basis for developing protocols on fish introductions and translocations in Australia and elsewhere. Impacts of Introduced Fishes The impact of introduced fishes may involve hybridization with endemic fish species, habitat and water quality alterations, competition for space and food, predation and the introduction of exotic parasites and diseases (Courtenay and Stauffer 1984; Moyle et al. 1986). Evidence of these impacts is considered in relation to representatives of the five families introduced into Australia, i.e., Salmonidae, Percidae, Cyprinidae, Poeciliidae and Cichlidae (Table 1). Hybridization Hybridization cannot occur in Australia because there are no indigenous representatives of the introduced species. However, hybridization has occurred between introduced European carp, Cyprinus carpio and goldfish, Carassius auratus (Hume et al. 1983) and between salmon, Salmo salar and brown trout, S. trutta in hatchery conditions (Johnson in Fletcher 1986). Of greater significance in Australia has been hybridization between two varieties of Euroçean carp to produce the vigorous Boolara strain, which spread explosively in the mid-1960's and 1970's and became far more widespread and problematic than any of the original stocks (Shearer and Mulley 1978; Pollard et al. 1980; Fig. 2). The Boolara strain is thought to be a hybrid between introduced mirror and fully scaled carp varieties of unknown origin. This parallels several cases of intraspecific hybridization among introduced plants, giving rise to locally adapted as well as aggressive variants (Barrett 1982). Electrophoretic analysis shows that populations of Mozambique tilapia, Oreochromis mossambicus, in Brisbane and Townsville, Queensland (Fig. 1) are very similar genetically but both differ significantly from populations of this species occurring in Cairns. The Cairns fish appear to be hybrids between 0. mossambicus and 0. hornorum, and possibly other species of tilapia as well (Mather 1988). Nothing is yet known about the physiological and ecological characteristics and consequent potential for spread of this mixed strain. G. affinis in Australia are all of the subspecies G. a. hoibrooki (Girard) (Lloyd a:id Tomasov 1985). Thus, there is no threat of hybridization between this and the nominate subspecies, G. a. affinis, with the attendant implications for future spread and ecological impact of hijbrid strains (see Reznik 1981). However, Australian populations of G. a. hoibrooki shdw marked morphological and genetic differences (Tomasov 1981): Trendall (1982) recorded substantial variations in life-history traits in four populations of G. affinis from Western Australia. Hybridization among phenotypically and genetically distinct strains of this subspecies is possible and could have unexpected outcomes.

20 9 Table 1. Introduced freshwater fish that have established self-maintaining populations in Australian inland waters. S. sport fish; A, aquarium fish; B, biological control agent. Compiled from various sources (see Arthington 1986). Family/Species Common Name Purpose of Introduction Salmonidae Salmo trutta L. Salmo gairdneri Richardson Sal velinus fonrinalis (Mitchell) Oncorhynchus tshawytscha Walbaum Salmo salar L. Percidae Percafluviatilis L. One-spot live- bearer Cyprinidae Cyprinus carpio L, Carassitss aural us L. Tinca tinca (L.) Rutilus rutilus L. Poeciliidae Gambusia affinis hoibrooki (Girard) Xiphophorus helleri (Gunther) Xiphophorus maculatus (Heckel) Poecilia reticulata Peters Poecilia lalipinna Le Sueur Phalloceros caudimaculatus Hensel Cichlidae Ore ochromis mossambicus (Peters) Tilapia mariae Bouienger Cichiasoma nigrofasciatum GUnther Brown trout Rainbow trout Brook trout Chinook salmon Atlantic salmon European perch or redfin European carp Goldfish tench roach Mosquitofish Swordtail Platy Guppy Sailfin molly Mozambique mouth- brooder Black mangrove or niger cichlid Convict cichlid S S S S S S S A S S AIB A A A/B A A A A A These examples highlight the need for more research on the genetic attributes of founding populations of successful (and unsuccessful) introduced fishes and on the genetic changes which may accompany colonization. The explosive spread of European carp in Australia is an outstanding example of the differential success of one genetic variant, and it is unfortunate that we have few data on relationships between genome, physiology and life histoiy traits in the highly successful Boolara strain of carp and the two varieties which have remained confined to the Prospect Reservoir, Sydney and the Murrumbidgee frrigation Area of Victoria (Fig. 2). Habitat Alterations There is very little evidence that introduced fishes have seriously altered aquatic habitats in Australia, either by degradation of water quality or by removal of aquatic vegetation or other forms of disturbance. McCrimmon (1968) attributed increased turbidity to the disturbance of

21 10 bottom substrates by European carp during feeding. However, Fletcher et al. (198,5) concluded that populations of carp have not caused increased turbidity levels in the Lower Goulburn River Basin, Victoria. Moyle et al. (1986) highlighted the direct and indirect influences of carp on shallow lakes in North America. When carp are removed, turbidity decreases and native invertebrate-feeding fishes that locate their prey by sight increase (Taylor et al. 1984). The impact of carp on turbidity in Australian aquatic ecosystems seems to be obscured by the naturally high md variable turbidity of many inland waters (Kirk 1977) and the interaction of hydrological factors with soil type and land degradation. Fletcher et al. (1985) also concluded that Potamogeton pectinatus, a shallow rooted, soft leaved species, may be the only aquatic plant reduced by carp in Australia. Most of the aquatic plants affected by carp in the United States and France are species of Potamogeto'z and Chara (Crivelli 1983). Xiphophorus helleri, the swordtail, is predominantly herbivorous, taking only a few aquatic invertebrates, but there is no clear evidence that its feeding has contributed to changes in aquatic macrophyte or algal communities in areas of introduction. Rather, the loss of endemic aquatic macrophytes from Brisbane's urban creeks has resulted from dredging, channel modifications, siltation, dumping of domestic and garden rubbish, bank erosion and the invasion of introduced plants (Arthington et al. 1983). The control of water hyacinth (Eichhornia crassipes) and other introduced plants with herbicides may also have contributed to the decline of so:ne endemic macrophytes. Numerous studies elsewhere have attempted to separate the effects of introduced species per se from the influence of other disturbances and natural environmental phenomena, with only limited success (Moyle et al. 1986). Australian researchers have experienced the same difficulties, as Arthington et al. (1983) and Fletcher et al. (1985) show in work on poeciliids and carp. Nevertheless, this is an area requiring much more study than it has so far received. Impacts of Competition on Endemic Fishes Resource competition for food, perhaps mediated by interference and aggressidn, seems a likely form of impact of many introduced species, particularly the mosquitofish, G. affinis. Taylor et al. (1984) and Arthington and Mitchell (1986) point out that successfu] introduced fishes typically exhibit generalist feeding habits and trophic opportunism. There is consequently considerable overlap in the diets of introduced and endemic fishes in many systems. G. affinis and Australian melanotaeniids, atherinids, galaxiids and a retropinnil have very similar diets (Arthington unpublished; Lloyd 1987). Moreover, the diet of the rainbowfish, Melanotaenja duboulayi (Castelnau) changes where large numbers of mosquitofish and small numbers of rainbowfish coexist. Also M. duboulayi tends to select larger prey items in the presence of G. affinis, which actively selects very small prey from the invertebrates in the stream environment. These shifts reduce dietary overlap between the two species, and may contribute to an effective partitioning of limited food resources. Environmental disturbances causing loss of aquatic macrophytes required for rainbowfish spawning habitat may also have been involved in the decline of this species (Arthington et al. 1983; Milton and Arthington 1984). There is other evidence that Australian fishes display niche shifts in coexistence with S. affinis but Lloyd (1987) recorded an expansion of niche width rather than a riduction as

22 predicted by competition theory (O'Connor et al. 1975). Some native fishes show shifts in distribution and abundance as a corollary of dietary niche shifts in the presence of G. affinis (Lloyd 1987). A mutually exclusive distribution pattern exists between mosquitofish and the pigmy perch, Nannoperca australis GUnther, in the Lower River Murray (Lloyd 1984; Lloyd and Walker 1986). Other species show much lower abundances in the presence of G. affinis and X. helleri than do populations of the same species in habitats without introduced fishes (Arthington et al. 1983; Lloyd 1987). The one-spot live-bearer, Phalloceros caudimaculatus and the guppy, Poecilia reticulata, have diets similar to that of the mosquitofish but are less aggressive species (Griffiths 1972). Their impacts on Australian endemic fishes have not been studied, although where guppies and G. affinis are abundant in Brisbane creeks, endemic fishes are rare (McKay 1978; Arthington et al. 1983). The ecological impact of interference competition as a result of aggression and fin-nipping by G. affinis has not been quantified, although it is thought to be important. Lloyd (1987) showed that mosquitofish would attack native fish twice their size and could inflict caudal fin damage. Schoenherr (1981) interpreted aggressive behavior of G. affinis leading to the suppression of reproduction in the Gila (Sonoran) topminnow, Poeciliopsis occidentalis, as interspecific competition for space. However, Meffe (1985) maintained that while some interference does occur, predation by G. affinis has been more important in the decline of the Gila topminnow. McKay (1978, 1984) suggested that large numbers of mosquitofish and swordtails in creek habitats could adversely affect endemic fishes. The decline of endemic fishes has most often occurred in disturbed and polluted habitats which introduced species such as poeciliids, cyprinids and cichlids are able to exploit (Arthington et al. 1983; Courtenay and Stauffer, 1984; Moyle et al. 1986). Nevertheless, G. affinis has colonized undisturbed waterbodies in Australia (Lloyd 1987) and appears to have caused the decline of an endemic rainbowfish, Rhadinocentris ornatus (Regan), in the near pristine environment of Eighteen-Mile Swamp on North Stradbroke Island, Queensland (Fig. 1.). Like G. affinis, the rainbowfish feeds predominantly on terrestial insects at the water's surface and small aquatic invertebrates (Bayly et al. 1975), and this may be a case of competitive displacement (Arthington 1984). However, predation on eggs and fry of the endemic species may also have been responsible. Exploitation competition with brown trout may be involved in the decline and fragmentation of range of the galaxiid, Galaias olidus Gunther, and the decline of river blackfish, Gadopsis marmoratus Richardson, since their diets are similar (Fletcher 1979; Jackson 1978). The diet of introduced carp overlaps at various body sizes with that of several endemic fishes, such as bony bream Nematolosa erebi Gunther, catfish Tandanus tandanus Mitchell, silver perch, Bidyanus bidyanus Mitchell, Australian smelt, Retropinna semoni Steindachner, carp gudgeon, Hypseleotris klunzingeri Ogilby and flat headed galaxias, Galaxias rostratus Klunzinger (see Fletcher 1986). Whether any of these species has been affected by exploitation competition is not known. 11 Impacts of Predation on Endemic Fishes G. affinis attacks the eggs and fry of important sports fishes, earning the name of "fish destroyer" (Myers 1965) and it is well known that mosquitofish may be piscivorous. However, Australian dietary studies have not produced any evidence of piscivory (Cadwallader 1979;

23 12 Arthington 1988; Lloyd 1987); G. affinis attacks and eats fish fry in aquaria (JoFnson 1976; Meffe 1985; Lloyd 1987). It is noteworthy that several small-bodied native fishe; seemingly affected by the mosquitofish in Australia have low fecundity (Milton and Arthington 1983b, 1984, 1985) but others do not. Brown trout, S. trutta, Chinook salmon, Onchorynchus tshawytscha and redfin Perca fluviatilis, feed selectively on small endemic fishes and fish fry and may have affected the numbers of galaxiids, pigmy perch, N. australis, and golden perch, Mac quara ambigua Richardson, in southern rivers (Fletcher 1986). Impacts of Predation in Invertebrates G. affinis has had destructive effects on invertebrate populations in field situations (Stephanides 1964; Legner and Medved 1974) and in controlled experiments. Taxa such as beetles (Walters and Legner 1980), back swimmers (Huribert and Mulla 1981), rotifers, Crustacea (Huribert et al. 1972) and molluscs (Rees 1979) have been affected. In Brisbane streams, G. affinis feeds on small terrestrial insects and immatu:e stages of aquatic insects in the drift and amongst aquatic plants, actively selecting very small prey (Arthington 1988). Such size selective feeding might affect the structure of invertebrate communities by altering recruitment of various taxa. However, the impacts of G. affinis and other invertebrate-feeding fishes on assemblages of invertebrates have not beer. studied in Australia and require attention. Brown trout feeding may have caused the decline of the Tasmanian mouni am shrimp, Anaspides tasmaniae, and has eliminated or reduced several Plecoptera and Trichoptera in Victorian streams (Fletcher 1979). In experimental ponds, carp have caused the decline of a species of Daphnia (Fletcher 1986). Introduction of Parasites and Diseases Many biologists have opposed the traffic of introduced aquarium species into Australia due to concern that diseases and parasites may also be introduced (Hoffman 1970; Me Kay 1984). There is already evidence that disease organisms have entered Australia via the aqu irium trade. Goldfish ulcer disease entered Australia this way (Trust et al. 1980) and has reccntly spread rapidly to wild stocks (Whittington et al., in press). Langdon (1986) and Langdon and Humphrey (1987) described a new viral disease of redfin, P. fluvitailis. Concern over imported lish diseases has led to the establishment of quarantine facilities at major ports handling aquarium stocks (McKay 1984). Fish introductions were responsible for importing fish parasites such as fish louse, Argulus (Williams 1980) and anchorworm, Lernaea cyprinacea (Roberts 1978; Hoffman a:id Schubert 1984). However, although G. affinis is host to 22 species of parasites in North America, there is only one Australian record of parasitism, a species of Lernaea found on mosquitofish from the River Murray (Lloyd 1984, 1987). The incidence of imported parasites in Australian endemic fishes is unknown. Moyle (1985) noted that endemic Californian fishes seem at time; to be more heavily parasitized by exotic parasites such as L. cyprinacea than do introduced fishes.

24 13 Overview of Impacts of Introduced Fishes The introduced species of most immediate concern in Australia are probably the aquarium species established in sub-tropical and tropical areas of Queensland, particularly G. affinis, X. helleri, P. reticulata and 0. mossambicus. Cold-water species such as salmonids have been in Australia for approximately 100 years and their impact has been of somewhat lesser concern, mainly because they are prized for sport fishing; yet there is growing evidence of their adverse affects. G. affinis has become a very common species in a wide variety of inland waters in 10 major Australian drainage systems (Fig. 1). Large populations occur in environments ranging from almost completely undisturbed, dystrophic swamps and streams to fetid urban drains with a wide variety of water quality problems. This fish may form part of the diet of water birds and endemic piscivores, although in the latter case it is avoided when there is a choice (Lloyd 1987). G. affinis is also considered to be less useful than various insectivorous endemic fishes as an agent in mosquito control (Lloyd 1986). Finally, several lines of evidence suggest that this species is partly responsible for the decline of several endemic fishes, including species which play an important part in keeping mosquito populations under control (Arthington et al. 1983; Lloyd 1984, 1986, Lloyd et al. 1986; McKay 1978, 1984). Thus the collective opinion is that G. affinis is a pest species, or ecological uweed (Lloyd 1984; Lloyd et al. 1986; Arthington and Lloyd, in press). X. helleri is also quite common in Brisbane, Queensland and in coastal streams further north, but its impact appears to be one of occupation of space rather than of herbivory. Nevertheless, its persistence and proliferation since introduction are of concern, particularly since it often occurs with G. affinis and the two species together in large numbers seem to depress endemic fish populations (McKay 1978; Arthington et al. 1983). P. reticulata occurs in many Queensland coastal streams (Fig. 1) and has a diet similar to G. affinis. Where guppies and G. affinis are abundant in Brisbane creeks, endemic fishes are rare (McKay 1978; Arthington et al. 1983). P. latipinna, X. maculatus and P. caudimaculatus are much more patchily distributed in Australia, but in sub-tropical and tropical areas of Australia, these species could spread and have an adverse effect on endemic fishes (McKay 1978; Balla et al. 1985). 0. mossambicus occurs in Brisbane, Townsville, Cairns and Western Australia, and new populations have been found in several other parts of Queensland. Some populations have been eradicated, but the species appears to be spreading, at least locally. For instance, numbers of mature fish were carried over the spillway of North Pine Dam, Brisbane, during a recent period of high rainfall, and have colonized (or recolonized) the lower North Pine River. This species also occurs in a tidal waterway in Cairns. It could possibly spread to new river systems via estuaries and coastal waters, in which it is able to breed (Hora and Pillay 1962). Although this species has been declared a noxious species in Queensland, with heavy penalties for translocation and cultivation (Arthington 1986), 0. mossambicus has turned up in isolated farm dams and ponds where its presence can only be attributed to human intervention. Ecological impacts of cyprinids, salmonids and the European perch in Australia are beginning to become evident but are far from fully understood (Pollard et al. 1980; Tilzey 1980; Fletcher 1986).

25 14 Apparent Extinction of the Lake Eacham Rainbowfish by Translocated Endemic Fishes The Lake Eacham rainbowfish, Melanotaenia eachamensis Allen and Cross, ocurs only in Lake Eacham, a large crater lake situated in a tropical rainforest catchment on the Atherton Tableland, northern Queensland (Fig. 1). Before 1984 the rainbowfish was an abundant species in the lake (Allen and Cross 1982; McKay 1987; Midgley, pers. comm.), which was also inhabited by two endemic species widespread in northern Queensland. Over the pa;t decade or so, several people noted the decline of the rainbowfish and the appearance in the SLake of four Australian species not previously recorded there. These species included the mout]i almightly, Glossamia aprion (Richardson), the archer fish, Toxotes chatareus (Hamilton), the bony bream, Nematolosa erebi (Gunther) and the banded grunter, Amniataba percoides (Gunther). The Lake Eacham rainbowfish has not been located during recent surveys (Barlow et al. 1987). Circumstantial evidence has been presented (Barlow et al. 1987) that its extinction may have been due largely to predation by the carnivorous G. aprion and possibly also the arher fish, T. chatareus; another endemic fish species and a crayfish also appeared to have become extinct in the lake as a result of predation. This first instance of an Australian native fish being exterminated by translocaled endemic fishes was initially noted and recorded by McKay (1987). McKay (pers. comm.) has suggested that this situation is unique in Australia, and could become a case history for rehabilitation of an aquatic ecosystem by the complete elimination of the translocated species in Lake Eacham, and then re-establishment of the rainbowfish by releasing hatchery bred stocks. He further suggests that the introduction of voracious predatory fish into Lake Eacham could achieve the desired eradication of resident, translocated fish species. By far the best candidate for this is the indigenous silver barramundi, Lines calcarifer Bloch. The barramundi is unable to breed in closed lakes and could therefore, in theory, be completely eliminated after extirpation of all translocated fishes either by allowing the introduced stocks to die out, or by a conccrted fishing effort. The Future Successful introduced fishes may experience local genetic differentiation follow:ng invasion of new environments (Arthington and Mitcheal 1986). Whether this occurs will depend on the kinds of environments encountered, the range and distribution of genetic variation available to populations, and the inheritance patterns of traits conferring increased fitness (Barret and Richardson 1986). There are several examples of adaptive changes in fish following colonization events. The mosquitofish exists as "warm-adapted' and "cold-adapted" strains in the USA (Otto, 1973) and a western Australian population of S. gairdneri exists with higher temperature tolera nce than its eastern counterparts (Morrissy 1973). The rainbow trout in New Zealand has superior swimming speed compared to ancestral stocks (Tsuyuki and Williscroft 1977). Tomasov (1981) showed that there are both morphological and electrophoretic differences between many Australian populations of G. affinis, but it is not known whether they have resulted from founder effects, genetic drift or local selection. Shifts in thermal tolerance might be expected in G. affinis from southern and ncrthern areas of Australia, where temperature regimes are very different. Likewise, X. helderi and 0.

26 mossambicus may be undergoing selection for cold tolerance in Brisbane since low winter temperatures have intermittently reduced some populations in streams and dams (McKay 1978, 1984). Shifts in critical physiological tolerances such as in temperature mean that the future range of an introduced species cannot be predicted with certainty. Appreciation of this and other problems has led Australian fisheries authorities to restrict the introduction of aquarium species and to reject the idea of introducing the nile perch, Lates niloticus to stock northern waterbodies for recreational fishing (Barlow and Lisle 1987). In part, the case made against the introduction of Nile perch was that it could colonize the upper reaches of the Murray-Darling River system and affect endemic fishes which are recruited from these waters. Adult 0. mossambicus die at temperatures ranging from 5-140C (Mar et al. 1966; Kirk 1972) so this species too could survive the minimum winter temperatures recorded in the upper Murray-Darling River (see Barlow and Lisle 1987). 15 An Ecological Approach to Predicting the Effects of Introductions There is worldwide evidence that successful fish introductions alter the structure and species composition of the invaded community. Australian examples are accumulating with increased research on introduced and translocated species. Herbold and Moyle (1986) and Moyle et al. (1986) have argued that introduced species do not fill "vacant niches" as Simberloff (1981) concluded from his review of species introductions. Rather, they fit into the new environment by further compressing the "realized niche" of one or more of the species already present, often to the point where the environment can no longer support the endemic species (Moyle et al. 1986). Li and Moyle (1981) applied the systems analysis technique of "loop analysis" to predict aquatic ecosystem behavior after a species introduction. They suggest that nutrient-poor or oligotrophic systems are most sensitive and become unstable after introduced species are established. Drawing upon the experience of entomologists in the biological control of pest species, Li and Moyle (1981) suggest four criteria for fish species that are candidates for introduction: trophic co-adaptation with members of the assemblage receiving the introduced species; narrow niche breadth including stenophagy; low vagility; and freedom from contagious disease and parasites exotic to the new environment. These criteria are the antithesis of the typical characteristics of successful and troublesome introduced species around the world, i.e., zero or little trophic co-adaptation, broad niches, especially habitat and trophic niche, high vagility and infection with parasites and diseases (Arthington and Mitchell 1986). Moyle et al. (1986) suggest that three areas of ecological theory are particularly relevant to predicting the effects of introduced species. The theory of island biogeography may answer the question "how many species can an aquatic ecosystem support?"; the concept of "limiting similarity" may aid in predicting how morphologically similar species can coexist in a community; and the analysis of food webs may be useful for understanding the trophic interactions of introduced and endemic species. Although each theoretical approach has weaknesses, Moyle et al. (1986) conclude that they all point to the creation of inherently unstable fish communities through poorly considered introductions and translocations. Fisheries scientists and managers now have access to a substantial body of theoretical and empirical evidence that "tinkering with fish faunas" (Welcomme 1984) is seldom entirely

27 16 successful and more often than not has unanticipated and undesirable consequences. If it is to continue, it must be preceded in every instance by full consideration of the probable consequences for the receiving ecosystem and its endemic fish fauna. This applies equally to the translocation of fishes between drainage systems, and is particularly important in Australia of the present time because of the renewed interest in stocking northern inland waters with endemic fish species to create recreational fisheries. Acknowledgements I wish to acknowledge research grants from the Australian National Parks md Wildlife Service, Griffith University and the Australian Water Research Advisory Council For the study of introduced fishes in Queensland. Mr. R.J. McKay, Mr. D.A. Milton, Ms. M. English, Mr. D. Bluhdorn and other colleagues are thanked for their part in these studies. I am also indebted to Mr. L.N. Lloyd for his substantial contribution to sections of this paper on poecihid :ishes. References Allen, G.R. and NJ. Cross Rainbowfishes of Australia and Papua New Guinea. Angus and Robertson, Sydney. Arthington, A.H Freshwater fishes of Stradbroke, Moreton and Fraser Island. In I. Covacevich and I. Davie (eds.) Fccus on Stradbroke, pp Boolarong Press, Brisbane. Arthington, A.H Introduced Cichlid fishes in Australian inland waters. In 0. Dc Deckker and W.D. Williams (eds.) Limnology in Australia, pp CSIRO, Melbourne and Dr. W. Junk, Dordrecht. Arthington, A.H Diet of Ganthgria affinis holbraoki (Baird and Girard) in streams of the Brisbane region, south-eastern Queensland, Australia. Proceedings (Verhandlungen) of the Societe Internationale Limnologie Arthington, A.H., D.A. Milton and RJ. McKay Effects of urban development and habitat alterations on the distributiost and abundance of native and exotic freshwater fish in the Brisbane region, Queensland. Australian Journal of Ecology 8: Arthington, A.H. and D.S. Mitchell Aquatic invading species. In R.H. Grooves and JJ. Bunion (eds.) Ecology of Biolcgical Invasions: an Australian Perspective, pp Australian Academy of Science, Canberra. Arthington, A.H. and LN. Uoyd (in press). Introduced Poecilädae in Australia and New Zealand. In G.K. Meffe and W.R. Omnenay (eds.) The Evolution and Ecology of Live Bearing Fishes. Prentice-Hall, New York. Balla, S.A., L.N. Lloyd and B.E. Pierce Unwanted aquarium fish. Search 16: Barlow, C.G. and A. Lisle Biology of the nile perch Lates niloticus (Pisces: Centropomidae) with reference to its proposed role as a sport fish in Australia. Biological Conservation 39: Barlow, C.G., A.E. Hogan and U. Rogers Implication of translocated fishes in the apparent extinction in the wild oj the Lake Eacham rainbowfish, Melanaaenia eachamensis. Australian Journal of Marine and Freshwater Research 38: Barret, S.C.H Genetic variation in weeds. In R. Charudattan and H. Walker Cods.) Biological Control of Weeds with Plant Pathogens, pp John Wiley, New Yojk. Barret, S.C.H. and BJ. Richardson Genetic attributes of invading species. In R.H. Grooves and J.J. Bunion (eds.) Ecc logy of Biological Invasions: An Australian Perspective, pp Australian Academy of Science, Canberra. Bayly, I.A.E., P. Ebsworth and Hang Fong Wang Ecology of Fraser Island Lakes. Australian Journal of Marine and Freshwater Research 24: Cadwallader, P.L Distribution of native and introduced freshwater fish in the Seven Creeks River System, Victoria. Aestralian Journal of Ecology 4: Cadwallader, P.L., G.N. Baclthouse and R. Fallu Occurrence of tropical fish in the cooling pondage of a power station in temperate southeastern Australia. Australian Journal of Marine and Freshwater Research, 31: Courtenay, W.R. and J.R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore. Crivelli, AJ The destruction of aquatic vegetation by caip. Hydrobiologia 106: Fletcher, A.R Effects of Salmo trulla on Galaxias olidus and macroinvertebrates in stream communities. M. Sc. Thesis, Monash University, Victoria, Australia. Fletcher, A.R Effects of introduced fish in Australia. In P. De Deckker and W.D. Williams (eds.) Limnology in Australia,pp CSIRO, Melbourne and Dr. W. Junk, Dordrecht. Fletcher, A.R., A.K. Morrison and D.J. Hume Effects of carp, Cyprinus carpio L. on communities of aquatic vegetation and nubidity of waterbodies in the Lower Goulburn River Basin. Australian Journal of Marine and Freshwater Research 36: ?. Griffiths, K A study of the depredations incurred among endemic Australian fishes by introduced fishes with particular reference to Ganthusia affinis. Teacher's Higher Certificate Thesis, Dept. Education, Western Australia. Herbold, B., and P.B. Moyle Introduced species and vacant niches. American Naturalist 128:

28 17 Hoffman, G.L Intercontinenial and transcontinental dissemination and transfaunation of fish parasites with emphasis on whirling disease (Myxosoma cerebral i4, p In S.F. Snieszko (ed.) A symposium on diseases of fishes and sheilfishes. Special Publication No.5. American Fisheries Society, Washington, U.S.A. Hoffman, H.L. and G. Schubert Some parasites of exotic fishes, p In W.R. Courtenay and J.R. Stauffer (ads.) Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore. Hora, H.W. and T.V.R. Pillay Handbook of fish culture in the Indo-Pacific region. FAO, Fish Biology Technical Paper No. 14. Hume, DJ., A.R. Fletcher and A.K. Morrison Interspecific hybridization between carp (Cyprinius carpio L.) and goldfish (Carassiiis awasus L.) from Victorian waters. Australian Journal of Marine and Freshwater Research 34: Hulbert, S.H. and M.S. Mulla Impacts of mosquitofish, Gambusia affinis, predation cat plankton communities. Hydrobiologia 83: Hulbert, S.H., J. Zedler and DJ. Fairbanks Ecosystem alteration by mosquito fishpredation. Science 175: Jackson, P.D Spawning and early development of the river blackfish, Gadopsis marmoratus Richardson (Gadiformes: Gadopsidae), in the Mackenzie River, Victoria. Australian Journal of Marine and Freshwater Research 29: Johnson, C.R Observations on growth, breeding and fry survival of Gambusia affinis affinis under artificial rearing conditions. Proceeding of Conference, California Mosquito Control Association 44: Kirk, J.T.O Anentuation of light in natural waters. Australian Journal of Marine and Freshwater Research 28: Kirk, R.G A review of recent developments in Tilapia culture with special reference to fish fanning in the heated effluents of power stations. Aquaculture 1: Langdon, J A new viral disease of redfin perch. Australian Fish 45: Langdon, J. and J.D. Humphrey Epizootic hernatopoietic necrosis, a new viral disease in redfin perch, Perca fluvitailis L. Australian Journal of Fish Diseases 10: Legner, E.F. and R.A. Medved The native desert pupfish. Cyprinodon maculatus, a substitute for Gambusia in mosquito control Proceedings California Mosquito Vector Control Association 42, Li, H.W. and P.8. Moyle Ecological analysis of species introductions into aquatic systems. Transactions American Fisheries Society 110: Uoyd, L.N Exotic fish-useful additions or 'animal weeds'. Fishes of Sahul 1: Uoyd, LN An alternative to insect control by "Mosquitofish", Gambusia affinis. p In T.D. St. George, B.H. Kay and J. Blok (eds.) Arbovinis Research in Australia. Proceedings Fourth Symposium, Brisbane, Uoyd, LN Ecology and distribution of small native fish of the lower River Murray, South Australia and their interactions with exotic mosquito fish, Gambusia affinis hoibrooki (Girard). M. Sc. Thesis, Dept. of Zoology, University of Adelaide. Uoyd, L.N., A.H. Arthington and D.A. Milton The mosquitofish, Gainbusia affinis, a valuable mosquito control agent or a pest?, p In R.L Kitching (ed.) The Ecology of Exotic Animals and Plants in Australasia. Jacaranda Wiley Press, Brisbane. Uoyd, LN. and J. Tomasov Taxonomic status of the mosquitofish, Gambtisia affinis (Poeciiidae), in Australia. Australian Journal of Marine and Freshwater Research 36: Uoyd, L.N. and K.F. Walker The distribution and conservation status of small fish in theriver Murray in S.A. Transactions Royal Society of South Australia 110: Mar, A.M., A.E. Mortimer and I. van der Lingen Fish culture in Central East Africa. FAO Publication No 5, /E. Mather, P Australian tilapia populations - a single problem 7 Paper delivered to the Annual Meeting of the Australian Society for Limnology, Townsville, Queensland, May McCrimmon, H.R Carp in Canada. Fisheries Research Board, Canada, Bulletin No McKay, Ri The exotic freshwater fishes of Queensland. Report to the Australian National Parks and Wildlife Service, Canberra. McKay, RJ Introductions of exotic fishes in Australia, p In W.R. Courtenay and J.R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore. McKay, Ri It's your problem tool Part 4. The Australian introductions. Aquarium Life Australia 2: Meffe, G.K Predation and species replacement in American Southwestern Fishes. A case study. Southwestern Naturalist 30:1-7. Meffe, G.K Conservation genetics and the management of endangered fishes. Fisheries 11: Milton, D.A. and A.H. Asthingion. l983a. Reproductive biology of Gambusia affinis Baird and Girard, Xiphophorus helleri (Gunther) and X. macviatiss (Heckel) (Pisces: Poeciiidae) in south-eastern Queensland, Australia. Journal Fish Biology 23: Milton, D.A. and A.H. Arthington. l983b. Reproduction and growth of Craterocephalus marjoriae and C. slercusmuscariwn (Pisces: Atherinidae) in southeastern Queensland, Australia. Freshwater Biology 13: Milton, D.A. and A.H. Arthington Reproductive strategy and growth of the crimson-spotted rainbowfish, Melanotaenia splendida fluvialitis (Castelnau) (Pisces: Melanotaeniidae) in southeastern Queensland. Australian Journal of Marine and Freshwater Research 35: Milton, D.A. and A.H. Arthington Reproductive strategy and growth of the Australian smelt Retropinna semoni, (Weber) (Pisces: Retropinnidae), and the olive perchlet, Arnbassis nigripinnis, (de Vis) (Pisces: Ambassidae), in Brisbane, southeastern Queensland. Australian Journal of Marine and Freshwater Research 36: Morrissy, N.M Comparisons of strains of Salmo gairdneri Richardson from New South Wales, Victoria and Western Australia. Australian Society of Limnology, Bulletin 5: Moyle, P.B Fish introductions into North America. In H. Mooney (ed.) Biological Invasions in North America. Springer-Verlag, Berlin. Moyle, P.8., H.W. U and B.A. Barton The Frankenstein effect. Impact of introduced fishes on native fishes in North America, p In R.H. Stroud (ad.) Fish Culture in Fisheries Management. American Fisheries Society, Bethesda, MD Myers, G.S Gambusia, the fish destroyer. Australian Zoologist 13: 102. O'Connor, Ri., P.J.S. Boaden and R. Seed Niche breadth in Biyozoa and a test of competition theory. Nature 25: Otto, R.G Temperature tolerance of the mosquito fish, Gambusia affirsis (Baird and Girard). Journal Fish Biology 5: Pollard et al Management of freshwater fish and fisheries, p In W.D. Williams (ed.) An Ecological basis for Water Resource Management. Australian National University Press, Canberra. Pyke, G.H., H.R. Pulliam and E.L Chamov Optimal foraging: a selective review of theory and tests. Quarterly Review of Biology 52: Rees, J.T Community development in freshwater microcosms. Hydrobiologia 63:

29 18 Reznick, D 'Grandfather Effects': The genetics of mterpopulation differences in offspring size in the mosquitofish. Evolution 35: Roberts, R.J Fish Pathology. Ballier Tindall, London. Schoenherr, A,A The role of competition in the displacement of native fishes by introduced species, p In R.. Naiman and D.L. Stolz (eds.) Fishes in North American Deserts. Wiley Jnterscience, New York. Shearer, K.D. and J.C. Mulley The introduction and distribution of the carp, Cyprinijs carpio Linnaeus, in Australia. Australian Journal of Marine and Freshwater Research 29: Simberloff, D.S Community effects of introduced species. In M.H. Nitecki (ed.) Biotic Crises in Ecological and Evolutionary Time, pp Academic Press, New York. Stephanides, T The influence of the anti-mosquitofish, Gambusia affinls, on the natural fauna of Corfulakelet. Praktika Hell. Hydrobiologie Institute 9: 3-5. Taylor, J.N., W.R. Courtenay and J.A. McCann Known impacts of exotic fishes in the continental United States, p In W.R. Courtenay and J.R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes, Johns Hopkim University Press, Baltimore. Tilzey, R.D.J Introduced fish, p In W.D. Williams (ed.) An Ecological Basis for Water Resource Management. Australian National University Press. Canberra. Tomasov. J.F Studies on an introduced Species. The mosquitofish - Gambusia affinis. B. Sc, Honours Thesis. Dept of Genetics and Human Variation, La Trobe University, Victoria, Australia. Trendall, J.T Covariation in life history traits in the mosquitofish, Gambusia affinis. American Naturalist 119: Trendall, J.T. andm,s. Johnson Identification by anatomy and gel electrophoresis of Phalloceros caudirnaculatus (Poe ciiidae) previously mistaken for Gambusia affinis ho! brooki (Poeciliidae). Australian Journal of Marine and FreshwaterResearch 32: Trust, T.J., A.G. Khouri, R.A. Austin and L.D. Ashbumer First isolation in Australia of atypical Aeromonas s,zlmonicida. FEMS Microbiology Letters 9: Tsuyuki, H. and S.N. Williscroft Swimming stamina differences between genotypically distinct forms of rainbow (Salmo gairdneri) and steelhead trout. Journal of Fisheries Research Board, Canada 34: Walters, L.L. and E.F. Legner Impact of the desert pupfish, Cyprinodon macularius and Gambusia affinis on fauna in pond ecosystems. Hilgardia48: 1-18: Welcomme, R.L International transfers of inland fish species, p In W.R. Courtenay and J. R. Stauffer (eds.) Distribution, Biology and Management of Exotic Fishes. Johns Hopkins University Press, Baltimore. Whiuington, RJ., N. Gudkovs, Mi. Carrigan, L.D. Ashburner and SJ. Thurstan (in press). Clinical, microbiological atid epidemiological findings in recent outbreaks of gold fish ulcer disease due to atypical Aerorrzonas salmonicida in south-eastern A ustralia. Journal of Fish Diseases. Williams, W.D Australian Freshwater Life. Macmillan, Sydney.

30 I 2 DARWIN J940 8B / GOVE PENINSULA I CAIRNS Lake Eacham i 1929 TOWNSVILLE 8 24 CARNARVO ROCKHAMPTON GLADSTONE 'p 24- ISBANE GERALDTON 30Q. PERTH 1934 ADELAIDE SYDNEY g, - 16 S MELBOURNE 0 (I Kilontre 1881 I 16 E 'W I 52 I I I I 42L Fig. 1. Australia showing major drainage divisions (1-12, see below), the localities and dates of major introductions of Gambusia affirns in Australia (e.g., Cairns 1929). the present distribution of G. affinis in each division (speckled areas), the location of Lake Eacham on the Atheston Tableland, south of Cairns, the distribution of Poecilia relic ulala in coastal Queensland (cross-hatched area), localities supporting Oreochromss mossamb,cus (Brisbane, Townsville and Cairns, Queensland; Gascoyne River and Lyons River east of Carnarvon, Western Australia). Numbers 1-12 refer to the drainage divisions recognized by the Australia Water Resources Council. Shaded areas indicate the presence of moaqustofish within at least parts of the drainage division (Aiihington and Uoyd, m press). 1. North-east Coast Division; 2. South-east Coast Diviaion; 3. Tasmanian Division; 4. Murray-Darling Division; 5. South Austrahan Gulf Division; 6. South-west Coastal Division; 7. Indian Ocean Division; 8. Timor Sea Division A - Cape Levesque Coast, B - Finnis River, 9. Gulf of Carpentaria Division; 10. Lake Eyre Division; 11. Bulloo-Bancannia Division; 12. Western Plateau Division.

31 ' 4 - I-.300 Cl) I of 0i,,ir1 '1 36 S I I I VICTORIA!4'o QUEENSLAND 'I I' I / I I NEW SOUTH WALES / / R / A 140E 146 l52 I I I ¼ IL 0 Kilometres / 500 LI L Fig. 2. South-eastern Australia showing state boundaries and the distribution of three strams of European carp, Cyprintts caipio. A - Prospect Reservoir strain, B - Mumimbidgee Irrigation Area (Riverina) strain and C - initial distribution of the Boolara strain, first introduced in Dashed lines indicate the distribution of the Boolara strain in 1977 (redrawn from Pollard etal. 1980).

32 Exotic and Translocated Freshwater Fishes in Australia RJ. McKAY Queensland Museum P0 Box 300, South Brisbane 4101 Australia McKay, Ri Exotic and translocated freshwater fishes in Australia, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Publ. 3, 154 p. Asian Fisheries Society, Manila, Philippines. Approximately 21 species of exotic freshwater fishes have become established in Australian waters, and some 21 indigenous species have been translocated. Two additional exotic species are maintained by regular stocking from Government hatcheries, and a number of unsuccessful introductions and unconfirmed reports of ornamental fish releases are documented in this paper. The freshwater fish fauna of Australia has been described as depauperate, of recent origin (with a few exceptions), and although similar, has had a dramatic impact on the natural environment to the extent that Weatherley and Lake (1967) and Lake (1971) contended that man-made changes to the environment have been the principal factors in causing a decline in the Australian fish fauna. The construction of large reservoirs, dams and weirs has impounded extensive bodies of permanent, or semipermanent freshwater, and these newly created habitats, albeit of short term evolutionary significance, have attracted the attention of "stocking associations". With mounting political pressure to provide recreational fishing in large reservoirs, without the provision of adequate research funds, and mindful of the reaction of a small but vocal conservation lobby, fishery managers frequently opt for the iranslocation of hatchery-bred native sport or food fish rather than to introduce an exotic species. The first recorded extinction of an indigenous freshwater fish in Australian waters, the Lake Eacham rainbowfish Melanotaenia eachamensis, was almost certainly due to the establishment of the translocated freshwater mouthbrooding apogonid Glossamia aprion (McKay 1987; Caughey 1987; Barlow et al. 1987). The advent of hormone-induced spawning of golden perch Macquaria ambiqua (Rowland 1983a), Murray cod Maccullochella peeli (Rowland 1983b), silver perch Bidyanus bidyanus (Rowland et al, 1983), barramundi Lates calcarifer (= L. cavzfrons), saratoga Scieropages leichardti (Merrick and Green, 1982), and a number of northern grunters (family Teraponidae), has stimulated the development of hatchery-bred indigenous freshwater fishes. A register of introduced exotics (Table 1) and translocated indigenous freshwater fishes (Table 2) was compiled by the author from the literature, fisheries reports, and personal communication, and this register, although necessarily incomplete, provides the basis for this account. All introductions and translocations in the register include locality, state to, origin, date, purpose, remarks and drainage system number (Surface Water Resources, 1967, Department National Development, Canberra) and are stored on an IBM compatible computer. 21

33 22 Definitions The terminology associated with introduced fishes is frequently imprecise (see Courtenay and Stauffer 1984); I have largely adopted the definitions given by Bruton and Mcrron (1985), with additional terms defined: Exotic Indigenous Endemic Introduction Stocked Translocation Established Invasive Species any species from another zoogeographic region. This term is usually applied to species from another country or continent (synonymous terms are alien and foreign). species native to a zoogeographic region, but no: necessarily restricted to a particular lake or drainage systems (synonymous terms are native or local). a species that is restricted in its distribution to a particular lake or drainage systems. the act of releasing or liberating one or more individuals of an exotic or indigenous species. The term includes both accidental and deliberate releases. an official or approved release for a specific purpose. Frequently employed by fisheries agencies when introducing hatchery-bred exotic or indigenous food or game fishes. the movement by man of a species within a zoogeographic region. A term generally used to describe the transplantation of indigenous populations either intentionally or unintentionally by man into a catchment or part of a catchment (above waterfalls) in which it was not naturally distributed, but may also refer to the movement by man of an exotic species within a zcogeographic region to which it was previously introduced. an introduced exotic or indigenous species that is reproductively successful (synonymous terms are acclimatized or feral species). a species which has the ability to become established in natural or semi-natural environments or communities, and to cause an ecological imbalance there (synonymous terms are colonizing or weed species). The introduction and establishment of exotic freshwater fishes in Australia has been regularly documented (Whitley 1951a, 1951b; Roughley 1955; Weatherley and Lake 1967; Lake 1971, 1978; McKay 1977, 1978, 1984, 1986a, 1986b; Pollard et al. 1980; Tilzey 1980; Welcomme 1981; Merrick and Schmida 1984; Arthington and Mitchell 1986). More recent introductions are given below in the species accounts.

34 23 Table 1. Exotic fishes established in Australian freshwaters. The states which such species is established is also indicated. Rainbow trout Brown trout Brook trout Carp Goldfish Tench Roach Mosquitofish One-spot livebearer Guppy Sailfin molly Platy Swordtail European perch Mosambique tilapia Tilapia Niger cichlid Convict cichlid Jack Dempsey Weather bach Salmo gairdneri, WA., S.A., Vic., N.S.W. Salmo lrulla, W.A., S.A., Vic., Tas., NS.W. Salvelinusfontinalis, Tas., N.S.W. Cyprinus carpio, S.A., Vic., N.S.W., Qd. Carassi,ss aural us all states except N.T. Tinca linca, S.A., Vic. N.S.W., Tas. Rutilus rutilus, Vic. Gambusia affinis ho! brooki, all states except Tas. Phalloceros caudimaculatus, W.A. Poecilia reticulata, N.S.W.,Qd., N.T. Poecilia lalipinna, Qd. Xiphophorus maculalus, Qd., N.T. Xiphophorus helleri, W.A., Qd., N.T. Percafluvialills, W.A., S.A. Vic., N.S.W., Tas. Oreochromis mossa,nbicus, W.A., Qd. Oreochromis sp. Qd. Tilapia,nariae, Vic., Qd. Cichiasoma (Archocentrus) niqrofascialum, Vic. Cichiasorna (Herichthys) octofasciatwn, Vic. Masqurnus angillicaudatus, A.C.T., Vic. The translocation of indigenous freshwater fishes has been recently documented (Anon 1980, 1982; Cadwallader 1981, 1983; Cadwallader and Backhouse 1983; Rowland et al. 1983; Cadwallader and Gooley 1984; Merrick and Schmids 1984; Brumley 1987). More recent translocations are discussed in the species accounts.

35 24 Table 2. Translocations of indigenous freshwater fishes. Queensland lungfish Bony bream Saratoga Gulf saratoga Dewfish Long torn Western rainbowfish Barramundi Murray cod Trout cod Australian bass Golden perch Macquarie perch Spangled perch Sooty grunter Mouth almighty Archerfish River blackfish Firetail gudgeon Western carp gudgeon Sleepy cod Neoceralodusforsteri, Qd. Nematalosa erebi, Qd. Scieropages leichardti, Qd. Sc!eropagesjardini, Qd. Tandantis tandanus, Qd. Strongylura kreffli, Qd. Melanotaenia splendida, Qd. Lates ca1carfer (= L cavifrons), Qd. Maccullochella peeli, A.C.T., Vic., N.S.W., Qd. Maccullochella,nacquariensis, N.S.W., Vic. Mac quaria novemaculeata, Vic., Qd. Macquaria ainbigua, A.C.T., Vic., N.S.W., Qd., N.T. Macquaria australasica, Vic., N.S.W. Leiopotherapon unicolor, Qd. Hephaestus bidyanus, Vic., N.S.W., Qd., N.T. Glossamia aprion, Qd. Toxotes chatareus, Qd. Gadopsis marmoralus, Tas. Hypseleotris gallii, Qd. Hypseleotris kluzingeri, Vic. Oxyeleotrts lineolatus, Qd. Table 3. Non-established, or introduced fishes of doubtful status. Quinnat salmon Atlantic salmon Tiger barb Pearl cichlid Jewel cichlid Oscar Cichlid Oncorhynchus tshawytscha, Vic. Salmo salar, Vic., N.S.W., Tag. Capoeta let razona, Qd. Geophagus brasiliensis, Qd. Hemichromis bimaculatus, Qd. Astronotus ocellatus, Qd. Cichlasoma sp. (hybrid), Qd.

36 25 Indigenous Species CERATODIDAE - LUNGFISH Neoceratodusforsteri Translocated to Brisbane, North Pine, Albert, Logan, Coomera, and Caboolture Rivers, but established only in the Brisbane and Pine River systems with any success (O'Connor 1897b; Merrick and Schmida 1984). CLUPEIDAE - HERRINGS Nematalosa erebi Established translocations in Lake Morris, Tinaroo Dam, and Lake Eacham, northern Queensland (Anon 1982). STEOGLOSSIDAE - BONYTONGUES Scieropages leichardti Translocated during the 1960's to Callide Dam, Borumba Dam, Moogerah Dam, Hinze Dam, Mary River, from (Borumba Dam) and North Pine Dam (pond escape) southern Queensland. Hatchery-bred fish sold in Queensland (Merrick and Green 1982). Scieropages jardini Tinaroo Dam northern Queensland (Anon 1982). PLOTOSIDAE - EEL-TAIL CATFISH Tandanus tandanus Translocated to Beatrice River, Lake Morris and Tinaroo Dam from Enoggera Dam, southern Queensland; to the Wimmera River, Victoria from the Murray River. Now produced by hatcheries and sold for stocking purposes (Anon 1982). BELONIDAE - NEEDLEFISH Strongylura kreffti Stocked into Callide dam (S.H. Midgley, pers. comm).

37 26 MELANOTAENIIDAE Melanotaenia splendida Translocated to Bolgu Island, Tones Straits, for mosquito control. CENTROPOMIDAE - BARRAMUNDI Lates calcarfer Translocated to Tinaroo Dam where they cannot establish. Hatchery-bred fish are sold in Queensland (Shacklee and Salini 1983). PERCICHTHYIDAE - BASSES AND CODS Maccullochella peeli Translocated to many localities within natural range and to Lake Charlegrark, Wimmera River lakes, Victoria. An early unsuccessful introduction to the Yarra River, Viccoria (Wilson 1857). Translocated from Condamine River to Obi Obi Creek, Mary River, Queensland in the 1880's (Cadwallader 1978, 1983; Cadwallader and Backhouse 1983; Rowland 1983b; Cadwallader and Gooley 1984). Hatchery-bred fish sold in Victoria, New South Wales and Queensland. Maccullochella macquariensis Stocked in Lake Sambell, Victoria, Seven Creeks and Glenbawn Dam, New South Wales (Cadwallader 1983; Cadwallader and Gooley 1984). Mac quaria novemaculeata Introduced to Lake Manchester and Poona Dam Queensland. Mac quaria ambigua Stocked in many reservoirs in New South Wales and Victoria (Cadwallader 1978, 1983; Anon 1980; Rowland et al. 1983; Rowland 1983a; Brumley 1987). Limited stocking in Queensland to date (Stephenson and Grant 1957). Stocked in Lake Burley Griffn, Canberra, (Pratt 1979; Robinson 1982). Hatchery-bred fish now available.

38 27 Mac quaria australasica Stocked in reservoirs in New South Wales and Victoria (Cadwallader and Rogan 1977, Cadwallader 1981b, 1983). A possible introduction to Lake Manchester, Southern Queensland with M. novemaculeata from the Nepean River (S.H. Midgley, pers. comm) Bidyanus bidyanus Stocked in reservoirs in New South Wales (Anon 1980; Rowland et al. 1983), and Wimmera River, Victoria (Cadwallader 1983), also stocked in Queensland dams (Yolk Creek, Enoggera, Kinchant, Tinaroo, Borumba, Boondooma and Awoonga) and Mary River. Hephaestus fuliginosus Stocked in 23 sites in Queensland from Tinaroo Dam southwards to Gin Gin (Anon 1980, 1982a). Early reports suggest that this species has become estabished in some coastal rivers. Liopotherapon unicolor Stocked in Maroochy River in the 1960s (S.H. Midgley pers. comm.) and into the North Pine Dam after 1973 where it has become established. Introduced to the Brisbane River system. APOGONIDAE - CARDINAL FISHES Glossamia aprion Stocked in some northern dams by private stocking agencies (Grant, 1982). Introduced to Lake Eacharn (see Arthingtonton - this volume). Toxotes chatareus Stocked in Tinaroo Dam, Copperload Darn and Lake Eacham, Queensland (Anon 1982a; Barlow et al. 1987). GADOPSIDAE - BLACKFISH Gadopsidae marmoratus Translocated to Huon and Derwent Rivers, Tasmania (Merrick and Schmida 1984).

39 28 ELEOTRIDAE - GUDGEONS Hypseleotris galii Introduced to Boigu Island, Torres Straits for mosquito control. Hypseleotris klunzingeri Introduced to Wimmera River lakes, Victoria with stocked species (Cadwallader and Backhouse 1983). Exotic Species SALMONIDAE -SALMON AND TROUT Oncorhynchus tshawytscha Maintained by stocking in south-western Victorian lakes (Cadwallader and Eden 1981; Cadwallader and Backhouse 1983). Salmo gairdneri The most important salmonid stocked in Australia. Widespread in Victoria, New South Wales and Tasmania (Roughley 1955; Lake, 1957; Weatherley and Lake 1967; Nicholls 1957, 1958a, 1958b, 1958c, 1958d; Wharton 1969; Lynch 1970; Tilzey 1971, 1972, 1976, 1977, 1980; McDowall and Tilzey 1980; Cadwallader and Tilzey 1980; Welcomme, 1981; Jackson 1981; Jackson and Davies 1983; Barnham 1983; Cadwallader 1983; Cadwallader and Backhouse 1983; Brown, 1984; Baxter 1985; Baxter et al. 1985). Salmo trutta (see also S. gairdneri) Widespread in Victoria, New South Wales, Tasmania and south-western Western Australia (Roughley 1955; Tilzey 1971; Jackson and Williams 1980; Merrick and Schmida 194). Salmo salar Maintained by stocking in impoundments in New South Wales and Tasmania (Francois 1965; Hortle 1986).

40 29 Salvelinusfontinalis Stocked in impoundments in New South Wales and Tasmania (Lake 1971; McDowall and Tilzey 1980; Cadwallader 1983; Merrick and Schmida 1984). CYPRINIDAE - CARP AND GOLDFISH Cyprinus carpio First introduced to Australia in 1872 and now widespread through the Murray-Darling system (Stead 1929; Lake 1959, 1967a, 1967b; Butcher 1962; Wharton 1971, 1979; Shearer and Mulley 1979; Smith and Pribble 1979; Geddes 1979; Mulley and Shearer 1980; Hume et al. 1983a, 1983b; Cadwallader and Backhouse 1983; McKay 1986c, 1987a; Arthington and Mitchell 1986). Carassius auratus Widespread in New South Wales, Victoria and western Queensland (Mitchell 1976; McDowall and Shearer 1980). Capoeta tetrazona Introduced to Enoggera Creek, Brisbane, Rutilus rutilus Common in some southern Victorian streams (Lake 1979; McDowall and Shearer 1980; Cadwallader and Backhouse 1983; Merrick and Schmida 1984). Tinca tinca Introduced to Tasmania and Victoria (Weatherley 1962; Weatherley and Lake 1967; Cadwallader and Backhouse 1983; Merrick and Schmida 1984). COBITIDAE - LOACH Misgurnus anguillicaudatus Released by aquarists to Lake Burley Griffin, Yarra River and Ovens River (Allen 1984, 1986c, 1987a).

41 30 POECILIIDAE - LIVEBEARERS Gambusia affinis hoibrooki Widespread throughout mainland Australia (Whitley 1951a, 1961b; Mees 1977; Pollard et al. 1981; Milton and Arthington 1983; Merrick and Schmida 1984; Lloyd 1984; Lloyd and Tomasov 1985; Arthington, this volume and references therein). Poecilia reticulata Common in urban streams throughout coastal Queensland (McKay 1977, 1978, 1984, 1986c; Arthington et al. 1983). Poecilia latipinna Established in Hervey Bay and Sandgate Lagoon, Brisbane (Mckay 1978, 1986c). Phalloceros caudimaculatus Established near Perth, Western Australia (Trendall and Johnson 1981). Xiphophorus helleri Common in urban creeks Brisbane, Ipswich and Gladstone Queensland (McKay , 1984; Arthington et al. 1981, 1983; Arthington and Mitchell 1986). Xiphophorus maculatus A rapidly spreading invasive species established in the Brisbane region, Babind a, Tully and Gordonvale, Queensland (McKay 1978, 1984, 1986c; Milton and Arthington 1983). PERCIDAE - PERCH Perca fluviatilis Established in western Victoria, New South Wales, Tasmania, Western Australia, and South Australian Gulf divisions (Weatherley 1963, 1977; Weatherley and Lake 1967; Cad'wallader and Backhouse 1983; Merrick and Schmida 1984; Baxter et al. 1985).

42 31 CICHLIDAE - CICHLIDS Oreochromis mossambicus A rapidly spreading invasive species established in Queensland and Western Australia (McKay 1984, 1986c; Allen 1982; Arthington et al. 1984; Arthington and Mitchel 1986; Arthington this volume). Tilapia mariae Established in thermal waters of a power station in Victoria (Cadwallader et al. 1980) and Cairns area Queensland. Cichiasoma nigrofasciatum Established in thermal waters of a power station in Victoria (Cadwallader et al. 1980). Cichiasoma octofasciatum Reported to be established (now declining population?) in thermal waters of a power station in Victoria (Cadwallader et al. 1980; N. Halliwell, pers. comm.). Geophagus brasiliensis Introduced to the Bajool area, Queensland, and in an ornamental pond, Rockhampton (McKay 1986c). Hemichromis bimaculatus Escaped from ornamental ponds cairns, Queensland and established in urban drains (McKay 1986c). Astronotus ocellatus Introduced to several urban creeks in Queensland but not yet established. Cichiasoma species Introduced to Brisbane River but unlikely to establish.

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Tilzey Management of freshwater fish and fisheries, p In Williams, W.D. (ed,) An Ecological Basis for Water Resource Management. Australian National University Press, Canberra. Pratt, B The Canberra Fisherman. Australian National University Press, Canberra, p. 123.

45 34 Robinson, S.E The ecology of Golden perch (Macquaria a,nbigua) in Lake Burley Griffin and Lake Ginnindera. Department of the Capital Territosy, A.C.T., Conservation Service, Conservation Memorandum 11: Roughley, T.C Fish and Fisheries of Australia. Angus and Robertson, Sydney, p Rowland, S., J. Dirou and P. Selosse Production and stocking of golden and silver perch in N.S.W. Australian Fisheries 42: Rowland, S.J. 1983, The hon-none-induced ovulation and spawning of the Australian freshwater fish golden perch. Iv'acquaria ambigua (Richardson) (Percichthyidae). Aquaculture 35: Russell, DJ Aspects of the limnology of tropical lakes in Queensland - with notes on their suitability for recreational fb,heries. Proceedings of the Royal Society of Queensland 98: Shacklee, J.B. and J.P. Salini Studies suggest multiple stocks of Australian barramundi. Australian Fisheries 42: Shearer, K.D. and J.C. Mulley The introduction and distribution of the carp, Cyprinu.s carpio Linnaeus, in Australia. Australian Journal of Marine and Freshwater Research 29: Smith, GJ. and H.J. Pribble A review of the effects of carp (Cyprinus carpio L.) on aquatic vegetation and water'owl. Fisheries and Wildlife Division, Victoria, Carp Program Publication 4: Stead, D.G An account of some experiments in the acclimatization of two species of Australian freshwater perch. Report of the Australian Association for the Advancement of Science 14(D): Stead, D.G Introduction of the great carp, Cyprinus carpio into waters of New South Wales. Australian Zoologist 6: 10(-l02. Tilzey, R.D.J the Lake Eucumbene trout fishery. Fishermen, N.S.W. 4(6): 1-9. Tilzey, R.D.J Observations on interactions between indigenous Galaxiidae and introduced Salmonidae in the Lake Eucumbene catchment, New South Wales. Australian Journal of Marine and Freshwater Research 27: Tilzey, R.D.J Key factors in the establishment and success of trout in Australia. Proceedings of the Ecological Society of Australia 10: Tilzey, R.D.J Introduced fish, p In W.D. Williams (ed.) An Ecological Basis for Water Resource Management. Australian National University Press, Canberra. Trendall, J.T Covariation of life history traits in the mosquitofish, G. affinis. American Naturalist, 119(6): Trendall, J.T. and M.S. Johnson Identification by anatomy and gel electrophoresis of Phalloceros caudimaculatus (Poec iiidae), previously mistaken for Gambusia affinjs hoibrooki (Poeciiidae). Australian Journal of Marine and Freshwater Research 32: 9) Weatherley, A.H Notes on distribution, taxonomy and behaviour of tench Tinca tinca (L.) in Tasmania. Annals and Magazine of Natural History 13(4): Weatherley, A.H Zoogeography of Percafluviatill.r (Linnaeus) and Percaflavescera (Mitchell) with special reference tc the effects of high temperature. Proceedings of the Zoological Society of London 141: Weatherley, A.H Percafluviazilis in Australia. Zoogeographic expression of a life-cycle in relation to environment. Jounial of the Fisheries Research Board of Canada 34: Weatherley, A.H. and J.S. Lake Introduced fish species in Australian inland waters, p In A.H. Weatherley (ed.) Australian inland waters and their fauna. Australian National University Press, Canberra. Welcomme, R.L Register of international transfers of inland fish species. FAO Fisheries Technical Paper 213: Wharton, J.C.F Trout liberations in Victorian streams and lakes from 1958 to Fisheries and Wildlife Department, Victoria. Fisheries Circular 19: Wharton, J.C.F European carp in Victoria. Fur, Feathers and Fins 130: Wharton, J.C.F Impact of exotic animals, especially European carp Cyprinus carpio, on native fauna. Fisheries and Wildlife Paper, Victoria 20: Whitley, G.P. 195la. Introduced Fishes - 1. Australian Museum Magazine 10: Whitley, G.P. 1951b. Introduced Fishes -2. Australian Museum Magazine 10: Whilley, K Dams boosting fish stocks. Australian Fisheries 39(6): Wilson, E On the Murray River cod, With particulars of experiments instituted for introducing this fish in the River Yarra-Yarra. Proceeding of the Royal Society of Victoria 2:

46 The Status of the Exotic Aquatic Organisms in China TAN YO-JUN TONG HE-Yl Shanghai Fisheries Universiiy 334 Jun GongRoad Shanghai, China Tan Yo-Jun and Tong He-Yi The status of the exotic aquatic organisms in China, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, ls4p. Asian Fisheries Society, Manila, Philippines. A total of 109 species of fish which includes 21 species of food fishes, 88 species of tropical aquarium fishes, 1 amphibian, 2 crustaceans, 6 molluscs and 7 seaweeds have been introduced into mainland China. Most of the food fish species are used for aquaculture. A strict quarantine procedure is adopted when species are introduced, and are released for commercial culture only after a number of years of experimentation and observation. As most introductions are tropical species, which are generally unable to overwinter under natural conditions, none of the introductions are known to have had deleterious effects on the indigenous flora and fauna. In order to develop China's inland and marine culture fisheries and other purposes, a great number of exotic aquatic species were introduced from different countries and regions of the world. There are about 125 species known to have been introduced into China. Among them are 109 species of fish which includes 21 species of food fishes and 88 species of tropical aquarium fishes, 1 amphibian, 2 crustaceans, 6 molluscs and 7 seaweeds. Some of them have been successfully cultured in different parts of the country and have made a considerable contribution to the production. Some are still in the stage of experimental culture. Pisces Exotic Aquatic Organisms in China Five species or subspecies of Cyprinidae were introduced into China (Table 1). Carassius auratus cuvieri which was called silver crucian carp in China, indigenous to Lake Biwa of Japan, was introduced into the country in 1976 and quickly popularized after 2-3 years trial. The principles of breeding and seed production are similar to that of local crucian carp Carassius auratus auratus. In the commercial production, silver crucian carp is commonly polycultured with the Chinese carps. It is now extensively cultured in China, particularly in Changjiang River Basin. Funtius gonionotus was introduced from Thailand in It has been experimentally monocultured or polycultured in ponds and rice fields in Guangdong Province. Labeo rohita is indigenous to the Ganges and was introduced from Thailand in It is being cultured experimentally in the southern parts of China. Catla catla was introduced from Bangladesh in 35

47 It has been cultured in southern parts of China, such in an experimental as in Guangdong Provincc, but is still stage. Scattered mirror carp is a strain of Cyprinus carpio which by German fish culturists was selected many years ago. Thirty thousand fertilized Japan in 1982 and eggs were intrcduced from ten thousand fingerlings were introduced from the Federal Republic Germany in The exotic of mirror carp has a fast growth easier to culture and catch, and rate, higher resistance to cold, is therefore it is now China. extensively cultured in the northrn parts of Colossoma bidens of Serrasalmidae, indigenous to South America, via Hong Kong. It is being was introduced in 1985 experimentally cultured in southern China. Three species of Clariidae have been introduced into China. Clarias batrachus Clarias macrocephalus and were introduced from Thailand in 1982 also distributed in southern and 1978, respectively. The latter is Yunnan Province of China. Clarias lazera Africa in In comparison was introduced from with the local catfish Clarias fuscus, the exotic cat fishes have more favourable characteristics for intensive culture, and are extensively China. cultured n southern Pangasius sutchi (Pangasidae) was introduced from Thailand in 1978, and at present is experimentally cultured in Guangdong Province. Ictalurus punctatus and Ictalurus nebulosus were introduced from and are experimentally cultured the United States in 1984 in Hubei Province and Beijing. Three coldwater salmonids have been introduced into China. Salmo gairdneri introduced from the Democratic was first People's Republic of Korea in slowly and remained 1959, but culture developed at experimental stage during Since then, rainbow has developed and it is trdut culture now extensively cultured throughout 16 regions. In 1983, The Donaldson provinces and autonomous super rainbow trout was introduced from Washington, USA. This species the University of has a faster growth and succeeded in rainbow trout culture stronger resistance to cold. China has and seed production. Food fish are mainly cultured in concrete tanks or raceways with running cok addition cage culture in lakes, water; in reservoirs and coastal waters is also and Coregonus sp. which carried out. Coregonus peled are species from USSR and North America from Japan in They originally, were introduced were cultured in a reservoir of Heilongjiang Province for Five species of Cichlidae have experiments. been introduced into China. introduced into China from Vietnam Oreochromis mossambicus was in 1957, and for a long period. It is was polycultured with Chinese carp; in ponds not considered a suitable species for culture and is being Oreochromjs nilorjcus, introduced replaced by in It has been monocultured in running warm polycultured in ponds. The hybrid water or of 0. mossambicus X 0. with Chinese carps. Oreochromis niloticus is important in polyculture aureus was introduced in 1981 in order offspring through hybridization. to get over O% male Tilapias are commonly cultured in ponds, running cages, etc. But Sarotherodon galilaeus and warm water, Tilapia zulu which kept in experimental were introduced in 19 1 are still hatcheries. Tilapias are unable to overwinter in natural waters in of China. most parts Largemouth bass Micropterus salmoides, indigenous to the freshwater North America, lakes and rivers in was introduced into China in 1983 via Hong Kong. Largemouti considered as one of the best food bass is fish species cultured in China. Gambusia affinis of Poeciliidae, indigenous to North America, several decades ago for controling was introduced into China malaria. It is widespread in Shanghai and Jiangsu iirovinces and is also cultured in aquaria.

48 It is well-known that the traditional aquarium fish of China are goldfish and brocaded carp. They were selected or bred from crucian carp and common carp, respectively. Many aquarium fishes were introduced from different countries and regions. The preliminary list of aquarium fish introduced into China is given in Table Crustacea Red crayfish Procambarus clarkii (Astacidae), indigenous to America, was introduced into China via Japan many years ago. It is self-reproducing in natural waters near Shanghai. The giant freshwater prawn Macrobrachium rosenbergii (Palaemonidae), indigenous to the Indo-Pacific region, was introduced into China from Japan. It is much bigger than the native freshwater shrimp Macrobrachium nipponense. At present, it is being mass cultured in Guangdong, Guangxi, Zhejiang, Fujian, Shanghai and Beijing. Mollusca The Pacific oyster, Crassostrea gigas (Ostreidae), was introduced into China from Japan in At present, it is being experimentally cultured in bays of Zhejiang Province. It is a good species with big size, fast growth and strong adaptability. The bay scallop Argopecten irradians (Pectinidae), indigenous to the Atlantic coast of the United States, was introduced into China in It is now cultured economically in some coastal areas of Shandong Province. Red abalone Haliotis rufescens and green abalone Haliotis fulgens (Haliotidae) were introduced into China from California, USA, and is been cultured experimentally. The red abalone is much bigger than the local abalone. A species of freshwater mussel Hyriopsis schiegeril (Unionidae) was introduced into Shanghai from Japan in The quality of freshwater pearls cultured from this species was probably better than those of local ones. Ampullarius gigas (Ampullaridae), indigenous to Brazil, was introduced into southern China via Hong Kong in It has been cultured in ponds, concrete tanks and ditches. Amphibia American bullfrog Rana catesbiana, indigenous to America, was introduced into China from Cuba in It has been cultured in parts of China. The natural distribution of the bullfrog is in swamp regions in Hunan Province and Xinjiang Autonomous Region. These frogs have now become established. Seaweeds (Algae) The kelp Laminaria japonica (Laminariaceae), indigenous to Japan, was accidentally introduced into China. In 1927, it was found growing off the coast of Dalian in northern China. It is theorized that zoospores attached to lumber rafts and to the bottom of cargo boats from

49 38 northern Japan, settled off Dalian. The first success in experimental culture was achieved in The species is cultured throughout China, especially in Zhejiang and Fujian Provinces, as a food and a source of iodine. Yields of 250,000 i/year dry weight have been obtained. A species of giant kelp, Macrocystis pyrifera, was introduced into China from Mexico in 1978 and United States in 1984, respectively. It has been experimentally cultured in some coastal areas of Liaoning and Shandong Provinces. Eucheuma sp. (Solieriaceae), indigenous to the Philippines, was introduced into China in It has been experimentally cultured in some coastal regions of Shandong Province. Besides these species of seaweeds, Porphyra nereocystis, Porphyra toru, Porphyra meniniata and Porphyra perforata were introduced into Shanghai from the United States in 1985, but none has established. Discussion Most of the exotic aquatic food species were introduced by research in:;titutes and universities in China, especially after 1950s. The ecological information and culture techniques of species were collected and studied; the advantages and unfavourable characteristics of exotic species were evaluated in detail prior to introduction. The species were quarantined and disinfected prior to introduction. After introductions, the exotic species were confined and cultured in experimental fishfarms in which intensive research on introduced species is undertaken before distributing them throughout the different provinces. Moreover, many species are indigenous to the tropics and are unable to tolerate the low temperature in winter in most parts of China, and the coidwater species cannot tolerate the water temperature in summer. As a result most exotic species have not caused seriou; ecological problems in natural waters. Some species such as Carassius auratus cuvieri are self-reproducing in natural waters and species such as Oreochromis spp. are easily bred under hatchery conditions. They have resulted in an increase in production and contributed to China's fisheries significantly. Fish feed supply is an outstanding problem in China's culture fisheries. The further development of fish culture has been limited by shortage of fish feed, especially those based on animal food sources. Therefore, among the exotic fishes which have been introduced into China, the omnivores and plankton feeders have been popularized quickly and widely. But carnivorous fish such as Micropterus salmoides are not easily spread although some can consume dead animal matter. It is more difficult to culture the native carnivorous fish Siniperca chuatsi, which feeds on live fish. Research on introductions will be continued; more attention should be paid to quarantine aspects so as to avoid the introduction of new diseases. Acknowledgements We are greatly indebted to Prof. Q.W. Meng for her encouragement, help and eonstructive suggestions. We should like to thank Prof. S. Q. Wang, Prof. J.X. Su, Mr. W.T. Wang and Mr. G.J. Ling for their valuable information.

50 39 Relevant Literature Cheng, T.H Production of kelp - a major aspects of China's exploitation of the sea. Economic Botany, 23(3): Fisheries Bureau of the Ministry of Agriculture of China Some technical information on the exotic species of aquaculture. Kuang, Y.T. and S.H. Liang Ornamental fishes and culture. Guangdong Scientific and Technological Publishing House. Tong, H.Y Recent development of China's inland fisheries. Manuscript submitted to the Fourth Session of IPFC working pasty of experts on inland fisheries, Sept. 1988, Kathmandu, Nepal. Zhang, Z.H Tropical fishes. Beijing Publishing House. Zheng, W.B. and J.H. Pan A newly introduced fish, Punlius gonionotus, for freshwater cultivation. Journal of Freshwater Fisheries 143: 3-7.

51 40 Table 1. The exotic aquatic food species introduced into China. Scientific name Common name Origin Year Pisces CYPRJMDAE Carassius auralus cuvieri Silver crucian catp Japan 1976 Punlius gonionolus Thai silver carp Thailand 1986 Catla calla Catla Bangladesh 1973 Labeo rohita Rohu Thailand 1978 Cypriniss carpio Scattered mirror carp F. Germany 1982 Aischgruhaer via Japan 1984 SERRASALM]DAE Colossoma bidens Freshwater pompano S. America via Hong Kong 1985 CLARIIDAE Clarias batrachus Walking catfish Thailand 1978 C. macrocephalus Catfish Thailand 1982 C. lazera Leather catfish Africa 1981 PANGASIDAE Pangasius sutchi Stripped/catfish Thailand 1978 ICTALURIDAE Ictalurus punctatus Channel catfish USA nebulosus Brown bullhead USA 1984 SALMONIDAE Sairno gairdneri Rainbow trout N. America via D.P.R.Korea 1959 Donaidsons super USA rainbow trout 1983 Coregonus peled White fish USSR 1985 Coregonus sp. via Japan USSR via Japan CICHUDAE Oreochromis mossambicus Mozambique tilapia Indonesia via Vietnam 0. niloticus Nile tilapia Africa aureus Blue tilapia via Hong Kong Africa 1981 via Hong Kong Sarotherodon galilaeus Africa 1981 Tilapia zulu Red belly tilapia Africa 1981 CENTRARCHIDAE Micropterus salnwides Largeinouth bass N. America 1983 via Hong Kong CRUSTACEA ASTACIDAE Procambarus clarkii Red crayfish N. America 1940? via Japan PALAEMONIDAE Macrobrachiu,n rosenbergui Giant freshwater prawn Thailand 1976 via Japan MOLLUSCS HAUOTIDAE Haliotis rufescens Red abalone USA 1985 H.fulgens Green abalone USA Continued

52 41 Table 1. Continued Scientific name Common name Origin Year OSTREIDAE Cra.raoslrea gigas Pacific oyster Japan 1979 PECTINIDAE Argopecten irradians Bay scallop USA 1982 IJNIONIDAE Hyriopsis sch!egerii Freswater mussle Japan 1982 AMPULLARIDAE Ainpullarius gigas Giant snail Brazil 1982 via Hong Kong AMPHIBIA Rana catesbiana American bullfrog Cuba 1962 ALGAE (seaweeds) LAMINARIACEAE Laminariajaponica Kelp, konbu Japan 1927 LESSONIACEAE Macrocystispyrfera Giant kelp Mexico 1978 USA 1980 SOLIERIACEAE Euchewna sp. Philippines 1985 BANGIACEAE Porphyra nereocyst is Layer USA 1985 P. torta Layer USA 1985 P. miniata Layer USA 1985 P.perforata Layer USA 1985

53 42 Table 2. The preliminary list of aquarium fish introduced into China. Scientific name Common name Origin OSTEOGLOSSIDAE Osteoglossum bicirrhoswn Arawana S. America CYPRIMDAE Barbus tetrazona Tiger barb Indonesia B. conchontus India B. nigrofasciatus Red ruby Sri Lanka Brachydanio rario Zebra danio India, Bangladesh Brachydanio albolineatus Pearl danio Bumia, India Danio,nalabaricus Giant danio Sri Lanka, India Punt ias oligolepis Checkered barb Indonesia P. titteya Cheny barb Sri Lanka Labeofrenalus Redtailed Thailand bicolor Red-tail shark Thailand Rasbora heteromorpha Hariguin rasbora, red Thailand R.,naculata Rasbora Indonesia R. pauciperforata Indonesia Epalzcorhynchuy kallopteru.s SE. Asia CHARACIL)AE Hyplsessobrycon inriesi Neon tetra Amazon H. caldinalis Cardinal tetra Amazon H. herbertaxeirodi Black neon tetra Brazil H. pulchripinnis Lemon tetra Amazon H. heterorhabdus Flag tetra Amazon H. callistus serpae Serpae tetra Amazon H. callistw.s rosaceus Amazon H. flammeus Brazil H. scholzie Black-band tetra Amazon Hemigrammus costello Amazon H. ocelljfer Head-tail light Amazon H. pulcher Pretty tetra Amazon H. rhodostomiss Red-nosed tetra Amazon H. caudoviutalus Argentina Anoptichthysjordani Blind caxe fish Mexico Gymnocoryi'n bus ternetzi Black tetra Bolivia Poedilobrycon unfasciauus One-line pencil fish Amazon Tyayeria sancuaemariae Penguin fish Amazon Alestes longipinnis Africa Aphyocharax rubripinnis Blood fin fish S. America Arnoldichihys spilopterus Nigeria Cheirodon axeirodi S. America Copeina arnoldi Amazon Anostomus anostomus Guyana Pristella riddlei X-ray fish Amazon Phenacogrammus interrupt us Congo Prionobramafiligera Translucent bloodfin Amazon SYNODONTIDAE Synodonuis nigrivenuris Updide-down catfish West Africa POECILIIDAE Poeciloa reticulatus Guppy S. America Molleiensia letipinna Black molly Mexico velifera Sailfin molly Mexico Xiphophoru.s helleri Red tuxedo swardtail Mexico X. macu!at us Moon fish, red platy Mexico X. variauus Vanatus platy Mexico Heterandria formosa USA Gambusia affinis Topminnow, mosquitofish N. America Continu xi

54 43 Table 2. Continued Scientific name Common name Origin CYPR1NODONTIDAE Aphyosemion bivitlaiwn Red lyretail W. Africa A. australe W. Africa A. gulare Nigeria A. sjoestedti Cameroon Aplocheilus lineal us India, Sri Lanka Jordanellafloridae N. America Epiplatys chaperi Liberia HEMIRHAMPHIDAE Derrnogenys pusillus Halfbeak Singapore Sumatra TOXOTIDAE Toxotesjaculator Archer fish India, Malaysia CICHLIDAE Plerophyliwn eimeki Angel fish Amazon P. scalare Angel fish Amazon Symphysoson dircus Discus Amazon Etroplus macuiat us Orange chromid S.E. Asia A.stronotus ocellatus Tiger oscar Amazon Cichlaso,na meeki Fire-mouth cichlid Mexico, Guatemala C. severum Banded cichlid Venezuela Apislogramma ramirezi Dwarf cichlid S. America A. agassizi S. America Aequidens maroni S. America Haplochromis multicolor Nile Pseudotropheus auratus C. America Pelmatochro,nis kribensis W. Africa CENTEROPOMIDAE Chanda ranga Glass fish Thailand, Bunna Gynochandanfilamentosa India, Buima Elassoma evergladei USA Mesogonistius chaetodon USA ANABANTIDAE Betta splendens Siamese fighting fish Thailand, Singapore Helostoma rudoiphi Kiss gouramy SE. Asia Trichogasler trichopterus Blue gouramy Thailand, India T. trichopterus sumatranus Mable gouramy Indonesia T. leeri Pearl gouramy Thailand Colisa la/ia Dwarf gouramy India C. labiosus Thich-lipped gouramy India, Bunna Trichoopsis pumilus Thailand Spacrichihys osphromenol Indonesia Colisa chuna India TETRAODONTIDAE Tel raodon schoutedeni Green puffer, spotted India, Thailand puffer

55

56 Impact of Exotic Aquatic Species in Indian Waters H.P.C. SHETTY M.C. NANDEESHA College of Fisheries University of Agricultural Sciences Mangalore A.G. JHINGRAN Central Inland Capture Fisheries Research Institute Barrackpore West Bengal Shetty, H.P.C., M.C. Nandeesha and A.G. Thingran Impact of exotic aquatic species in Indian waters, p In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. A number of food, game, larvicidal and ornamental fishes have been introduced into India since over a centusy. Of more than 300 exotic species introduced into the country, the majority are aquarium fishes. Among the food fishes the majority belong to the cyprinid group, the prominent among which are the common, silver and grass carps. Grass carp has proved useful both as a culture fish and as an effective biological agent for weed control. Accidental entry of silver carp into Gobindasagar reservoir has resulted in decline in the production of Indian major carps, as well as in total catch. The bighead, introduced recently through private trade is also causing serious concern. The Java tilapia, Oreochromis mossambicus, is considered a pest, though it continues to form a commercial fishery in some reservoirs and is also cultured in some parts of the country. Some of the salmonids introduced into the country have peiformed well and are gaining increasing popularity. Among the molluscs, the giant African snail holds promise for export, while posing a pest problem in certain regions. The accidentally introduced fouling bivalve Mytilopsis sallei is causing grave concern. Water hyacinth and Salvinia are the two exotic plants which have become a major menace in the fishery waters of the country. India, with its very extensive freshwater resources, has a wide spectrum of native aquatic fauna and flora. All the same, there have been introductions of several exotic aquatic species into the country since over a century. Early introductions mainly consisted of game fish, food fish of minor importance and larvicidal fish. In the post-independence era, a number of cultivable fishes have been introduced with the objective of increasing production from aquaculture. Apart from these, innumerable ornamental fishes have also been introduced into the country at different times. Though these introductions have helped to widen the species spectrum, their impact on indigenous icthyofauna in capture and culture fisheries has not been properly evaluated until now, eventhough it has been realized that some of the introduced fishes have adversely affected the indigenous species. Apart from fishes, a large number of aquatic plants have also been introduced into the country and a few of them also have severely damaged the fishery waters. Therefore, an assessment of the present status of such introductions is urgently needed. 45

57 46 Present Status of Exotics in India The major exotic introductions and their impact on the indigenous fauna in,eneral and aquaculture in particular, are dealt with in the following section and are listed in Tabls 1 and 2. Food Fishes Trout The areas around the Himalayas in the north and the peninsular hilly regions in the south are temperate in climate, and suitable for the culture of cold water fish. The first attempt to introduce trout as a sport fish was made in 1863 by Francis Day in Nilgiris of peninsular India. However, rainbow trout (Salmo gairdneri) from Sri Lanka, Germany and New Zealand were the first salmonids to be established in many streams of Nilgiris. The submergence of a number of trout streams in the newly formed reservoirs and increasing pollution of the remaining s'ieams have led to a sharp decline in the trout fishery in the post-independence era. In an attempt to improve the trout fishery efforts have been made to introduce some new species such as brown trout and tiger trout (hybrid between brown trout and eastern brook trout (Salvelinusfontinalis) and sockeye salmon (Onchorhyncus nerka). Among the various species of trout introduced in Nilgiris so far, only the rainbow trout has survived under the existing climatic conditions. It appears that trout culture is no longer an economical proposition in NiIgiris region due to pollution of streams and serious disease problems (Sreenivasan et al. 1988). Similarly, in the Himalayan region, introduction of trouts commenced after nearly three decades of their introduction in the Nilgiris region. Of all the introductions into the Himalayan region only brown trout provides a fishery on a commercial scale in streams (Sehgal 1988). Though attempts are being continued to establish trout populations in the cold regions of northern and eastern India, the success is not always commensurate with the efforts, largely due to stocking of undersized fish and the increasing pollution of streams. However, in some high altitude lakes, like Deodital of Central Himalayas, the brown trout has established itself and is breeding naturally (John and Prasad 1988). According to Jhingran and Sehgal (1978), altogether 719 km of trout streams are available in the country, in addition to over 4000 ha of natural and man-made lakes with trout?opulations. The analysis of creel census data provided by the anglers has revealed that the brown trout catches were around g/rod/hr/km fishable length in the Himalayan region in 1971, while in the Nilgiris in the south, the catch was about 457 g/rod/hr/km during (Jhingran and Sehgal 1978). As compared to some other introduced fish species, the trout have remained noncontroversial because of their restricted distribution and lack of indigenous cold water sport fishes. The populations of Schizothorax spp. do not appear to have been adversely affected by the presence of trout. Golden carp The crucian carp or golden carp (Carassius carassius) was introduced into India in 1874 in the Ooty lake at Nilgiris. The fish thrived well in Nilgiri waters and formed an important fishery

58 47 Table 1. Salinonids introduced into India. Common Name Scientific Name Year of Country of Introduction Origin Brown trout Salmo fru!tafario U.K. Loch Leven trout Salmo 1evensac 1863 U.K. Rainbow trout Salmo gairdneri 1909 Sri'Lanka, Germany, New Zealand Rainbow trout Salnw gairdneri 1968 Japan (Golden variety) Tiger trout Salmo truttafario 1969 Japan SalvelinusfontinalLs Sockeye salmon Onchorhyncus nerka 1970 Canada Albino trout Sairno gairdneri 1974 Japan Steelhead trout Salmo gairdneriirideus U.K. & Sri Lanka Rainbow trout (Shasta strain) Salmo gairdneri shasta 1941 U.K. Eastern brook Salvelinusfontinalis trout Canada Splake trout Salvelinus namaycisshx Canada SalvelinusfontinalLr Atlantic salmon Salmo solar North America Table 2. Introduced food and larvicidal fishes into Indian waters. Common Name Scientific Name Year of Country of Introduction Origin Golden carp Carassiiss carassius 1870 U.K. Tench Tinca tinca 1870 U.K. Gourami Osphronemus goramy 1865 Mauritius 1916 Java Scale carp Cyprinus carpio var 1939 Sri Lanka comniunis Mirror carp Cyprinus carpio var 1939 Sri Lanka specularis Leather carp Cyprinus carpio var 1939 Sri Lanka nudus Bangjcok strain Cyprinus carpio var 1957 Thailand communis Silver carp Hypophtha!michthys 1959 Japan,nolitrix Grass carp Ctenopharyngodon 1959 Hong Kong idella Tawes Puntisssjavanicus 1972 Indonesia Java tilapia Oreochronric mossambicus 1952 Thailand & Sri Lanka Nile tilapia Oreochromis niloticus Bighead carp Aristichthys nobilis Barbados millions Lebistes reticulatiss 1908 South America Top minnow Gambusia affins 1928 Italy

59 48 for a few years. The species attains over one kg in weight and breeds in ponds, like common carp. However, with the introduction of common carp, with which it shares a common habitat, the fishery of golden carp has dwindled drastically. Common carp The Prussian strain of common carp introduced in Nilgiris in 1939 from Sri Lanka consisted of three varieties (Table 2). Since the Prussian strain was mainly suited for cul:ure in cold climates, the Bangkok strain of common carp was introduced from Bangkok in 1957 for culture in plains. However, both strains are now widely cultured throughout the country. The common carp is one of the species usually included in composite carp culture in India. Its proportion varies from 10-30%, depending on the type of culture. The food habits of common carp are similar to those of mrigal (Cirrhinus mrigala), a species commonly included in composite culture. The common carp has been found to be more suitable for sesona1 water bodies. Under Indian conditions, the fish attains an average weight of kg in the first year and matures when it is just 6-8 months old. It breeds naturally even in impoundments. Even though common carp has been introduced into most of the reservoirs and lakes in the country, it is well established only in a few of these water bodies. On the other hand, it is believed that the common carp is responsible for the sharp decline in the abundance of Schizothorax spp. in Dal Lake in Kashmir and Osteobrama belangeri in Loktak Lake in Manipur (Das 1988). Silver carp The silver carp, Hypophthalmichthys molitrix, was introduced with the objective of filling up a vacant ecological niche in the pond culture system (Tripathi 1958). This fish occupies the surface - column zones of a pond and feeds voraciously on phytoplankton. In its native habitat in China, it matures in 4-6 years (Kuronuma 1968), but does not breed naturally even after hormone injection in India and needs to be stripped about 6-8 hr after the second injection. The silver carp has become one of the major controversial species in Indian aquaculture. Though the species was considered to be ecologically non-competitive with Indian major carps, long experience in culture has shown that it competes with catla to some extent. The species is usually stocked at 20-30% in composite culture, and its contribution to total production is usually higher than its stocking percentage. Its poor keeping quality and market value, coupled with its competition with other species, have raised some doubts about its suitability in composite culture. Apart from its declining popularity in culture practices, the species has caused concern to ecologists by its presence in Gobindasagar (10,500 ha) reservoir in Himachal Pradesh. From 1974 the silver carp started appearing in increasing numbers and in it contributed 46.5% to the total catch (Table 3). This clearly indicates that the species has established itself in the reservoir. Significantly, with the increasing contribution of silver carp, catla and rohu catches have declined sharply. In addition, the total catch of the reservoir has also declined, possibly indicating the negative effect of silver carp on other fish. The introduction of silver carp into Kulgarhi reservoir has led to similar resulis (Natarajan 1988).

60 49 Grass carp The grass carp, Ctenopharyngodon idella, was introduced mainly for purposes of biological control of submerged aquatic vegetation in fishery waters, in particular Hydrilla, Vallisneria and smaller floating weeds like Lemna sp. However, because of its fast growth rate, it was very soon included as a component in composite fish culture. It does not usually breed naturally even after hormone injection and therefore has to be stripped. It feeds on aquatic weeds and more voraciously on soft aquatic vegetation like Hydrilla, but does not feed on Eichhornia, Pistia and Salvinia (Singh et al. 1967) and grasses and leaves of leguniinious plants. The grass carp has been widely used in the country for weed control in canals (Kulshreshthra and Sharma 1976; Singit, pers. comm.), water cooling tanks (Chaudhuri et al. 1976) and ponds (Keshavanath and Basavaraju 1980). In composite culture systems, the grass carp lends an added advantage in that it consumes vegetation more than its own body weight and voids most of it in semi-digested form, which serves as food for omnivorous fishes and also as pond fertilizer. The introduction of grass carp, therefore, has proved beneficial. Tawes The Tawes, Puntius javanicus, is known to be macrophagous, and is cultured in only some parts of the country. It breeds naturally and attains a weight of over one kg in a year. However, the species is not popular in culture practices in India. Tench The Tench (Tinca tinca) introduced into Nilgiris in 1874 is established well in the Nilgiris region and individuals weighing over 1 kg can be caught from Ooty Lake. It matures in the 2nd or 3rd year and breeds under pond conditions. However, recent reports indicate the disappearance of the tench from Nilgiris waters (Sreenivasan et al. 1988). Bighead carp Bighead carp (Aristichthys nobilis) were accidentally introduced into India (Das 1988), where they remained confined to the fish farm of Central Inland Fisheries Research Institute at Cuttack and later disappeared altogether. They have reportedly reappeared in the country in 1987, presumably through private trade from Bangladesh. Jhingran (1985) has discussed in detail the likely consequence of the introduction of bighead to Indian waters. Its feeding habits are similar to that of catla and is likely to pose a threat to catla. The suitability of bighead is yet to be assessed in terms of consumer preference, growth rates under Indian conditions and disease resistance.

61 50 Gourami The gourami Osphronemus goramy, an anabantid, has been cultured in several states for nearly four decades, but with little success. Because of its slow growth, it is no longer actively cultured anywhere in the country. However, it has established itself in waters in some parts of peninsular India. Because of its nest building habit, the rate of survival of its progeny is high. Being phytophagous, it also serves to control aquatic weeds to some extent. Tilapia The Java tilapia Oreochromis mossambicus, a cichlid, is the most controversia among the exotics in India. Apart from the official introductions, this fish has also found its way into the country through unofficial transplantation from Bangladesh by private entrepreneurs. Even though the Government of India has never advocated the commercial culture of tilapia and its introduction into natural water bodies, it has spread to several parts of the country and has even established itself in some reservoirs (Sukumaran and Tripathi 1988; Chandrasekeran and Sreenivasan 1988). A number of factors has led to overpopulation and stunted growth. Though the fish has been found to feed predominantly on phytoplankton, in the absence of :Lts preferred food it tends to be an omnivore and sometimes even a carnivore (Jhingran 1974). Tilapia was cultured with encouraging results during the initial stages, production ranging from ,000 kg/ha/yr (Chandrasekaran and Sreenivasan 1988). The catches from a few reservo:lrs in Tamil Nadu are given in Table 4 and it is apparent that there is a general decline in tilapia catches over the years. It is quite difficult to eradicate this fish from where it has already gained a permanent foothold (Natarajan 1988; Jhingran 1988). It is reported that another species of tilapia, 0. niloticus, has already been introduced through private trade in West Bengal and is being cultured in sewage-fed farms. Table 3. Catch composition in Gobindsagar Reservoir (in tonnes; percentages are given in parentheses). Year Total (t) Common carp Catla Silver carp (14.80) (26.00) (1.46) (19.23) (29.91) (1.41) (23.39) (13.50) (1.74) (29,72) (5.68) (6.09) (17.59) (8.28) (14.68) (17.59) (8.28) (14.68) (23.30) (4.79) (18.25) (28.06) (5.97) (25.15) (18.08) (8.30) (44.18) (22.47) (5.45) (44.70) (18.84) (5.29) (46.76) (Source: Kuldeep Kumar, personal communication)

62 Table 4. Total catch and tilapia yield (in tonnes) in some reservoirs of Tamilnadu. Year Amaravathy Total Tilapia Total Vaigai Tilapia Bhavanisagar Total Tilapia Tirumoorthy Total Tilapia Upper Dam Total Tilapia Total Krishnagiri Tihipia ND- -ND ND- -ND- (87.93) (80.47) ND- -ND ND- (95.86) (87.96) (42.22) ND- -ND ND- (82.73) (68.76) (7 2.49) Nil Nil ND- (88.45) (68.34) (64.74) Nil Nil ND- (91.76) (70.50) (27.3 9) Nil (84.77) (0.72) (33.82) (40.38) (3.79) Nil Nil (79.40) (32.40) (6.11) (2.75) ND (80.00) (13.82) (21.55) (39.54) (3.52) ND (49.57) (13.78) (12.22) (43.87) (3.39) ND- -ND ND (15.10) (53.74) (20.92) (22.99) (4.38) (19.07) (0.05) (23.96) (13.01) (Source: Sreenivasan, pers. comm.); ND - No data; Figures within parentheses indicate percentage contribution to total catch.

63 52 Larvicidal Fish The poeciliid Lebistes reticulatus was introduced for mosquito control. It is reported that one more species of larvicidal fish, Notobranchus sp. has also been introduced (Sreenivasan et al. 1988). However, these fish have not been widely employed for the purpose they were introduced. On the other hand, Gambusia affinis is known to adversely affect the fishery of other fishes by preying on their spawn. In Ooty Lake, this fish severely affected the mirror carp fishery and only after its eradication, the mirror carp fishery could be reestablished. Ornamental Fish A large number of ornamental fish, consisting of both egg layers and live bearer;, have been introduced into the country over the years. Baskar et al. (1988) have reported the presence of 261 species of exotic egg layers in India. However, they contribute about 25% to the country's export trade, which is dominated by the domestic egg layers. Subramanian et al. (1988) listd a total of 27 exotic live bearers in India. A number of different strains are reported to exist within these. Exotic aquarium fishes are considered important from the view point of developing export and domestic trades. Molluscs Mytilopsis sallei This exotic bivalve, which is native to Central American region, appears to have been brought into Indian waters through ship fouling in the late 1960s. It has become a major fouling pest, gaining almost monospecific dominance in fouling communities, with a biornass build up of to kg/m-2/yr. This bivalve is also seen in large numbers in Kakinada harbour, but only to a small extent in Bombay Harbour. It appears highly probable that this fouling organism will pose a serious problem in the country (Rao et al. 1988). Aquatic Plants Over the last century, several aquatic plants have been introduced into the couniry, but a full list of these is not readily available. However, only a few of them are of importance from a fisheries point of view in that they have proved harmful. Foremost among them is the water hyacinth (Eichhornia crassipes), which was reportedly brought from Australia for its flowers. This fast growing weed has become the single biggest menace in fishery waters and navigation channels. Even though effective mechanical and chemical methods for eradication of this weed are known and also practised off and on, failure to take suitable follow-up measures has invariably led to reinfestation. Its growth is particularly pronounced in waters receivlng domestic sewage. Recent experiments have shown the possibility of biological control of this weed using the insect Neochitina eichhorniae (Jayanth 1987). Some recent studies have indicated the possibility of useful utilization of this obnoxious weed, such as in bio-gas production (Joglekar and Sonar 1986), and fish feed (Anil et al. 1986).

64 Salvinia molesta, a floating fern of South American origin, is another obnoxious weed infesting the Indian fishery waters. It was earlier noticed only in the backwaters of Kerala, but is now slowly spreading to other areas. Though it has been demonstrated that this fern could be controlled easily by spraying aqueous (1-2%) ammonia, the technique is not used widely because of certain inherent limitations. However, recent investigations have indicated the possibility of complete elimination of this weed using the insect Cyrtobagous salviniae (Jayanth 1987; Joy et al. 1985). Pistia stratiodes and Ipomea carnia, both of south American origin, are the two other obnoxious exotic weeds. Even though the present extent of infestation is much less compared to water hyacinth and Saivinia, there is need to contain it before they too pose a serious threat to fishery waters. As it is, 2-4 D has been found to be effective in controlling these weeds (Ramachandran and Prabhu 1988). 53 Conclusions and Recommendations The deliberations of the Indian Branch of the Asian Fisheries Society at its Workshop on Exotics, April 1988, form the main basis for the conclusions and recommendations listed below. The Chinese carps have helped in increasing fish production to 10 t/halyear from composite fish culture, involving three Indian major carps and three exotic carps. However, as compared to the Indian carps, the consumer preference is rather low for the exotic carps, particularly the silver carp, because of its poor keeping quality. It is now known that silver carp competes with catla for food to some extent. The Chinese grass carp has proved most useful and efficient in the biological control of submerged weeds. It has also proved to be a good table fish. Under Indian conditions, it grows fast and can easily be maintained on any of the submerged aquatic weeds, terrestrial grasses and leaves of leguminous plants. The accidental introduction of silver carp into a few reservoirs has led to a sharp decline in the catla population, as well as total fish production. As the Prussian strain of common carp is the only species of exotic carp that can do well in upland waters, more emphasis is required to be given for its propagation in upland waters. In water bodies where tilapia has already gained a firm foothold, it should be possible to reduce its numerical dominance by continuous stocking of these water bodies with major carps. Some other species of tilapia are known to have better cultivable qualities than Oreochromis mossambicus. It may be desirable to consider introduction of some species into India purely for experimental purposes, to assess their suitability for culture under Indian conditions either by themselves or through the production of hybrids. There does not appear to be a need to introduce any new salmonids. Instead, good hatchery facilities should be developed for the existing species and more attention given to their genetic improvement, and prevent degradation of the ecology of trout streams because of pollution. Instead of introducing a number of species for different purposes, improvement of the genetic quality of the indigenous major carps should be given more attention. It is also necessary to regulate the introduction of exotic species into neighbouring countries, such as Nepal, Bhutan, Pakistan and Bangladesh through existing regional organizations, since such introduced species could easily cross over into Indian territory.

65 54 Some of the exotic aquarium fishes have established themselves very well in the country and have a good export demand. Therefore, it is imperative to initiate research on their breeding and mass culture to boost the export trade. A number of exotic aquatic weeds have already become a nuisance in the country's fishery waters. Concerted effort should, therefore, be made to develop suitable methods for their control and utilization. The reported illegal entry of fishes, such as the bighead carp and Oreochrornis niloticus into the country is required to be viewed seriously. Until such time that their utility i.s proven in controlled experiments, their trade and culture should be banned. No exotic fish, however successful elsewhere, should be introduced into Indian waters without first ascertaining their utility under controlled conditions. Even if an exotic fish competes with a commercially important indigenous fish, if in all respects the former is proven to be better such introductions could be possibly permitted, but steps must be taken to ensure that the indigenous species is not endangered. All introductions of exotic species must be controlled by a central agency like the Ministry of Agriculture, Government of India or the Indian Council of Agricultural Research and no private agency should be permitted to import exotic species. At present, there is no proper quarantine procedure in respect of fish impor:ations. The common diseases now encountered in trout farms, viz. 'whirling' disease caused by Myxosoma cerebra/is and 'ich' disease caused by Ichthyophthirius multifihis are of exotic origin (Sreenivasan et al. 1988; Sehgal 1988). Similarly, the origin of a few parasites like Tripartiella spp. and Neoergasilus japonicus are traced to Chinese carps (Das and Halder 1988) Therefore, there is an urgent need to develop suitable quarantine facilities and to lay down a proper quarantine procedure. References Anil, K., I.P. Keshavanath and M.C. Nandeesha Water hyacinth as a substitute for fish meal in carp diet. Paper prsented at the 7th International Symposium on Aquatic weeds, September, Loughborough, England. Baskar, S.L, P.S.R. Reddy, B. Subramanian and RJ. Lazanis Exotic freshwater aquarium fishes and their role in the aqusrium fish trade of India I. Egg layers. Paper presented at the workshop on Exotic Aquatic Species in India, April, Mangalore. Chandrasekaran, A. and A. Sreenivasan Introduction of tilapia in Tami]nadu. Ibid. Chaudhuri, H., D.S. Murthy, R.K. Dey and P.V.G.K. Reddy Role of grass carp, Ctenopharyngodon idella (Val.) in biclogical control of obnoxious aquatic weeds in India: a review, p In C.K. Varshney and J. Rzoska (eds.) Aquatic weeds in South-east Asia. Dr. W. Junk Publishers, The Hague. Das, P Exotic fish germplasm resources in India and their conservation. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Dat, M.k. and D.P. Halder Parasitc fauna of cultured exotic carps in India: its biological significance. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Ghosh, A., L.H. Rao and S.K. Saha Culture prospects of Saroiherodon mossambicus in small ponds fertilized with lomestic sewage. Journal Inland Fisheries Society, India 12: Ghosh, A., A. Ghesh, P.K. Chakraborthi and G.N. Chattopadhyay Later calcarifer as a biocontrolling agent for Oreochi-mis mossambicus in sewage-fed impoundments. Paper presented at the Work shop on Exotic Aquatic Species in India, April, Mangalore. Jayanth, K.P Suppression of water hyacinth by the exotic insect Neochitina eichhorniae in Bangalore, India. Current Science 56: Jayanth, K.P Biological control of the water fern Sal vinia,nolesta infesting a likely pond in Bangalore (India) by Cyrtcbagous salviniae. Entomophaga 32: Thingran, A.G Some considerations on introduction of tilapia into Indian Waters. Bulletin Bureau Fish Genetics Research, 34 p. Jhingran, A.G The scope and limitations of introducing the bighead carp Aristichthys nobilis (Richardson) in inland waters of India. Bulletin Bureau Fish Genetics Research, 18 p. Thingran, A.G Status of exotic fishes in Indian capture fishery. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Jhingran, V.K. and R. Prasad Impact of introduction of trout (Salrno truttafario and Salmo gairdneri) in Garhwal ]imalayas in India. Paper presented at the workshop on Exotic Aquatic Species in India, April, Mangalore.

66 Joy, PJ., K.R. Sathesan and D. Joseph Successful biological control of the floating weed Salviniae nwlesta Mitchell using the weevil Cyrtobagous salviniae Sands in Kerala (India). Asian-Pacific Weed Science Society 10th Conference, November 24-30, Chiangmai, Thailand. Keshavanath, P. and Y. Basavaraju A note on utility of grass carp, Ctenopharyngodon idella (Valenciennes) in controlling the aquatic weed, Hydrilla. Current Research 9: Kulshresthra, S.D. and K.P. Shamia Biological control of aquatic weeds in the Chambal Comm and Area of Kota using grass caip, Ctenop/zaryngodon idella (Val.). Joumal Inland Fisheries Society, India 8: Kuronuma, K New system and new fishes for culture in the Far East. FAO Fisheries Report 5: Mishra, B.K., A.K. Sahu and C. Pani Recycling of the aquatic weed, water hyacinth and antmal wastes in the rearing of Indian major carps. Aquaculture 68: Mitra, A., T.K. Nayak and S.K. Sarakar Culture of Oreochromis nwssambicus under different culture system in West Bengal, its social acceptance and economic retum. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Natarajan, A.V Ecological and aquacultural roles of exotic fishes in aquatic productivity in India. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Pandian, T.J. and K. Varadaraj Techniques to regulate sex ratio and breeding in tilapia. Current Science 56: Ramachandran, V. and T. Ramaprabhu Major exotic aquatic weeds in India - present status of knowledge. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Rao, K.S., V.V. Srinivasan and M. Balaji Spread of the exotic fouling bivalve, Mytilopsis sallei (Recluz) in Indian harbours. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Sehgal, K,L State-of-art of exotic coldwater fishes in India. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore Singh, S.B., K.K. Sukumaran, K.K. Pillai and P.C. Chakrabarti Observations on efficacy of grass carp, Clenopharyngodon idella (Val.) in controlling and utilizing aquatic weeds in ponds in India. Proceedings Indo-Pacific Fisheries Council 12: Shetty, H.P.C. and M.C. Nandeesha Status of exotic aquatic species in Indian waters. Paper presented at the workshop on Exotic Aquatic Species in India, April, Mangalore. Sreenivasan, R., P.S.R. Reddy, B. Elambarithy, IS. Baskar and R.J. Lazarus Exotic freshwater aquarium fishes and role in the aquarium fish trnle of India. II. Live bearers. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Sukumaran, K.K. and S.D. Tripathi Oreochromis mossambicus - a controversial exotic Species in Indian waters. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. Tripathi, S.D Silver carp (Hypophthalmichthys molitrix) and grass carp (Clenopharyngodon idella) -- exotic elements in freshwater carp polyculture in India. Paper presented at the Workshop on Exotic Aquatic Species in India, April, Mangalore. 55

67

68 Exotic Aquatic Species Introduction into Indonesia H. MUHAMMAD EIDMAN Faculty of Fisheries Bogor Agricultural University Darmaga Campus, Bogor Eidman, H.M. 1989, Exotic aquatic species introduction into Indonesia, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proecedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. The knowledge on the biology of the large freshwater fish fauna of Indonesia is limited. Domestication of endemic species has not been done intensively. Introduction of exotic species started long time ago by the fish traders especially as ornamental fish. Intended introduction of aquatic species in later years was for aquaculture, ornamental purposes and mosquito eradication. Some introductions have been beneficial while others directly or indirectly disturb the ecosystems. Indonesia as an Indo - Australian archipelago consists of many islands, and spreads between Pacific and Indian oceans. It has a rich flora and fauna. This paper will deal mainly with freshwater organisms since introduction of marine organisms is limited, and sparsely documented. The freshwaters of the western part of Indonesia (Sunda region) which includes Sumatra, Kalimantan and Java are inhabited by more than 500 indigenous species of fish, 70 % of which belong to Ostariophysi and Labyrinthici, the dominant freshwater groups. Eastern Indonesia (Sahul region) which includes Irian Java has more than 100 fish species and is dominated by euryhaline species. Central Indonesia (Wallace region) which includes Sulawesi and the Nusa Tenggara is inhabited by some 50 fish species (Ondara 1982). Even the endemic fish fauna is numerous, but little is known of their life histories, which hampers their domestication. Instead of domesticating the local species, which of course needs more time and effort, people tended to take short cuts by introducing the already domesticated species available in the market. Some species improved the fisheries and aquaculture production while others were a failure. Present Status of Exotic Aquatic Species in Indonesia Information on the introduction of fish into Indonesia was reviewed by Schuster (1950). The major introductions are summarized in Table 1. The introductions into Indonesia are divisible into a number of eras. 57

69 58 Table 1. Introduced aquatic species into Indonesia. Date Species Source Remarks pre 1900 Cyprinus carpio China The exact yeal is not Carassius' auratu.s known, continuously introduced 1915 Ctenopharyngodon Malaysia and Accidental idella, Labeo molitorella Singapore 1920 Lebistes ret kul at us Unknown Malaria eradic ation; unsuccessful 1927 Tinca vulgaris Netherlands Inland Fisheris (tench), Cyprinus Department carpio (Galician race) 1929 Salmo trutta iridea Netherlands Inland Fisheries Depart- (rainbow trout) ment; unsuccessful Salmo Irutla fario (river trout) Salmo salar (salmon) Netherlands Gambusia affinis Unknown Accidental, mixed with Cyprinus carpio Netherlands local varieties (Frankish race) 1934 Trichoga.ster Malaysia Inland Fisheries pectoralis (Regan) Department; Successful (Snake Skin Gouramy) 1937 Salmo truttafario New Zealand Mr. Missegas (river trout) (EnglishmarL) unsuccessful 1939 Salmo trullafario Denmark Collaboration with Inland Fisheries Department Australia Oreochromis Unknown Found in the South mossambicus Peters coast of East Java by Mr. Mudjair 1949 Clenopharyngodon idella Thailand Inland Fisheries Department, Unsuccessful 1964 Clenopharyngodon idella Japan Introduced by Mr Rustami Djajsdiredja 1967 Hypophthalmkhlhys molitrix Japan ditto 1967 Hypophthalmichthys molitrix Taiwan ditto 1969 Oreochromis nilolicus Taiwan ditto 1969 Arislichlhys nobilis Taiwan ditto 1969 Cirrhina,nolitorella Taiwan ditto 1972 Pangasius sutchi Thailand ditto 1986 Ictalurus punctalus USA experimental purposes (channel catfish) (RIFF)* 1987 Carassius aural us (Koi) Taiwan experimental purposes Other Organisms Clarias gariepinu.s Unknown Fish dealer, (catfish) experimental Rana catesbiana Unknown Commercial, not (bullfrog) successful yet Eichhornia crassipes Unknown Wide spread (water hyacinth) Eucheuma cotton ii Philippines As aquaculture species, good results Serrasalmus sp. (pirranha) Unknown Fish trader, exterminated * REFF Research Institute for Freshwater Fisheries (formerly: Inland Fisheries Department)

70 59 Early Years Cyprinus carpio L. and Carassius auratus L. were believed to be the first exotic species introduced into Indonesia. These fishes have been imported from China by ornamental fish dealers. In Malang (East Java) and Bogor (West Java) a number of fish-breeding places were established and some fish probably escaped into open waters. Cyprinus carpio importations were continuously done until recently and they have mixed with the older ones. This species became the most common fish cultured in fresh water ponds, cages and running water systems. The 1920s Lebistes reticulatus (Peters), guppy is an aquarium fish species which escaped into ponds and open waters in Bandung, West Java. In warm waters, Lebistes appeared to degenerate in size. They do not feed on mosquito larvae; they are not valuable in mosquito control in Java. Instead, they compete with plankton feeders. Another aquarium fish that escaped to the open waters is Gambusia affinis. However, it has disappeared now. In 1929, the Inland Fisheries Department imported live rainbow trout Salmo trutta iridea Gibb. from the Netherlands to Indonesia and they were reared in the mountain area of Malang. The eggs of the rainbow trout (Salmo trutta iridea Gibb.), the river trout (Salmo truttafario L.), as well as salmon (Salmo salar L.) were hatched and fry were released into the streams of Kawi mountain in East Java. These fish could not live in warm waters during the dry season and they have since disappeared altogether. Eggs of Salmo trutta fario L. were imported again from New Zealand (1937), Denmark and Australia (1939), hatched and fry of 15 cm were released into mountain streams. However, the attempt was not successful. The 1930s The Inland Fisheries Department imported Trichogaster pectoralis (Regan) from Malaysia. At the beginning it was difficult to breed this species. However, in 1935 breeding was successful and in 1937 this species began to spread and become economically important. Presently this species is widely cultured in ponds and are also successfully established in open waters. The occurrence of Oreochromis mossambicus (Peters), the Java tilapia, in Indonesia is still not clear. This species was caught first in Java by Mr. Mudj air, whose name was later given to it on a suggestion of the Inland Fisheries Department. Due to its adaptability and because it breeds easily, it became one of the most important freshwater fishes in Indonesia. For the small-scale fish farmer and the low income groups this species is very useful. However, in more capital intensive aquaculture the Java tilapia is considered to be a competitor or trash fish. Aside from being a food fish the Java tilapia is also useful for malaria eradication.

71 60 The 1940s The Inland Fisheries Department imported the grass carp, Ctenopharyngodon idella (C. et V.) from Thailand to Java. The purpose of importation was to study its aquaculture potential. The prospects for grass carp in Indonesia are bright. There are many lakes and other water bodies with abundant aquatic plants that can be utilized by this species. It is used for experimental purposes. The 1960s The silver carp (Hypophthalmichthys molitrix) was first introduced into Indonesia in 1964 and again in 1969 from Taiwan. Experiments done at the Research Institute for Freshwater Fisheries, Bogor, and the breeding experiments using hypophysation techniques were successful in Silver carp is a plankton feeder; it grows faster than other plankton feeders (Trichogaster pectoralis and Helostoma temmincki). This species is still used for experimental purposes (Hardjamulia 1978). The purpose of importing this species is to utilize plankton more efficiently. ]However, this species is not yet popular in aquaculture. Oreochromis niloticus was introduced into Indonesia in Its performance is considered to be better than 0. mossambicus. This species is already spread widely and is very popular among fish farmers; it is an example of a successful introduction of an exotic species in Indonesia. To utilize the natural food available in ponds, it is suggested that this species be cultured in combination with carp and Puntius javanicus or with carp and giant gouramy. In 1969, four species of fish were imported to Indonesia from Taiwan: Hypophthalmichthys molitrix, Oreochromis niloticus, Aristichthys nobilis and Cirrhina molitorella Hardj amulia 1978). The 1970s Pangasius sutchi Fowler was imported to Bogor in 1972 from Bangkok. Ereeding was successful using hypophysation technique. The prospect of this species for aquaculture is good. Growth rate is high and it can be cultured intensively (Effendi 1975; Hardjamulia 1.978; Ondara 1982). The 1980s With the improvement of the economy, fish consumption in the larger cities increased. Besides other fishes, demand on Cyprinus carpio has increased. There is a shift in the method of carp culture from stagnant water ponds and cages to more intensive culture in running water systems. This rush for carp running-water-system culture was suddenly disrupted by the outbreak of haemorrhagic septicemia which started in Cibening near Bogor. The disease is thought to have been caused by Aeromonas salmonicida and Aeromonas hydrophilia in combination with a virus. Other species that became victims of this disease included Osphronemus goramy and Clarias

72 batrachus. It remains uncertain whether the pathogens were brought through fish importations or not. Whatever the cause, this disease outbreak awakened the Government that the introduction of exotic species may have disastrous effects. Outbreaks of this magnitude have not occurred earlier. The measures which have been taken seem to be effective. Channel catfish (Ictalarus punctatus) was imported from the United States for experimental purposes. There is no available information on its suitability for aquaculture in Indonesia as experiments are still in progress (Balitkanwar 1987). Koi (Carassius auratus) was imported from Taiwan for experimental purposes. This ornamental fish is becoming very popular especially in big cities. Breeding so far has been successful (Balitkanwar 1987). 61 Other Aquatic Organisms Introduced into Indonesia Clarias gariepinus - imported by fish dealers; became very popular and is called 'lele dumbo". Rana catesbiana - bull frog (Amphibia), still in experimental stage; commercial scale not profitable due to difficulties in providing proper food (Achatinafulica as feed). Anodonta woodiana - fresh water mollusc; introduced from Taiwan together with the importation of Oreochromis niloticus and Hypophthalmichthys molitrix. The larvae (Glochidium) use fish as their host (Suseno 1978; Djajasasmita 1979). Eichhornia crassipes - water hyacinth. It has become a nuisance in reservoirs. Mechanical, chemical and biological eradication methods have not been successful. Among others Rawa Pening (Central Java), Saguling Reservoir, Curug Reservoir are infested. Eucheuma cottonii - seaweed. Cultured together with Eucheuma spinosum which is endemic. Good results were reported in Bali. Conclusion and Suggestions Introductions of exotic species are likely to be continued either intentionally or unintentionally for emotional, commercial or ecological reasons. Studies on the aquatic ecosystems should be encouraged in order to obtain basic information. The impact of introductions can be predicted with additional knowledge of the candidate exotic species. 3. Local aquatic species should be investigated for their suitability for aquaculture and as ornamental fish.

73 62 Indonesia includes three different areas of fish distribution: the Western area (Sunda region); the Eastern area (Sahul region) and the Central area (Wallace region), with different fish populations and aquatic organisms. Suitability in one place does not necessarily hold for the other parts of the country. Law enforcement, facilities for quarantine, education and extension on the usefulness and danger of careless introductions are necessary. Cooperation and mechanisms between exporting and importing countries to safeguard the success of interchange of aquatic species should be developed. References Balitkanwar, A, Keadaan Kan lele annorika (Hetalurus punctatus) selama Nopember 1986-Manet Laporain: 2. Balitkanwar Pusitbankan Bahtbangtan Departmen Pertanian. lop. (In Indonesian). Balitkanwar, A Keadaan kam leoi (Carassius auratus) asal Taiwan selama 16 Nopunka-28 Manet Balitkanwar, Pusitbankan, Balitbangtan, Departmen Pertanian. 7 p. (In Indonesian). Djajasasmita, M Bagaimana cara Kijma Taiwan Anodonta woodiana, Lea 1837 dapat menyelundup ke Indonesia. (Flow the Taiwanese clam Anodonta woodiana, Lea 1837 could infiltrate into Indonesia) Buletin Kebun Raya, Vol 1, No. 4, KeburL Raya-LBN- L1P1, Bogor. (In Indonesian). Effendi Momahed Ichsan Masalah introduksi jenisikan baru (Problems of the new fish species introduction) WART A PERIKANAN - Communications on Agriculture. No. 33, 5th Year, Department Pertanian, Jakarta, Indonesia, p (In Indonesian) Hardjamulia, Atmadja Budidya Ikan Mola (Hypophthalmichthys molitrix), ikan grass carp (Clenopharyngodon idellus), ikan jambal Siam (Pangasiu.s sutchi Fowler) dan ilcan nila (Tilapia nilotica). Untuk sekolah usaha perikanan menengah Budidya Bogor Departmen pertanian BPLPP - SUPM Budidya, Bogor. 33 p. Lecture mimeograph (In Indonesian). Hardjamulia, Atmadja and Rustami Djajadiredja Notes on the contributions of introduced species, Tilapia nilotica, and Hypophthalmicthys molitrix, to the development of fishculture in Indonesia. ASEAN meeting of experts on Aquaculture, Semarang, Indonesia, 31 Januaiy-6th Febmaty p. Ondara, M Beberapa cetatan tentang perairan tawa dan fauna iknannya di Indonesia (several notes on freshwater and its fauna in Indonesia) Prosiding simposium perikannan petairan Umum No. 1 - Prosd. No. l/sppu/82, Departmen pertanian, Jakarta, Indonesia, p (In Indonesian with English abstract) Schuster, W.H Comments on the importation and the transplantation of different species of fish mto Indonesia. Contributions Gen. Agriculture Research Station, Bogor, Indonesia, No. 111: Suseno, DJOKO Kijing Taiwan Anodonta woodiana Lea 1857, (Taiwanese clam Anodonta woodiana Lea 1857). WARTA PERIKANAN - Communications on Agriculture, No. 46, 8th Year, Deparimen Pertanian, Jakarta, Indonesia, p (In Indonesian)

74 Present Status of Aquatic Organisms Introduced into Japan KENJI CHIBA Fisheries Laboratory Faculty of Agriculture University of Tokyo 2971, Maisaka, Hamana Shizuoka YASUHIKO TAKI KIYOSHI SAKA! Tokyo University of Fisheries Konan, Minato Tokyo 108 YOSHIOKI OOZEKI Dept. of Fisheries Faculty of Agriculture University of Tokyo Yayoi, Bunkyo, Tokyo 113 Chiba, K., Y. Taki, K. Sakai and Y. Oozeki Present status of aquatic organisms introduced into Japan,p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154 p. Asian Fisheries Society, Manila, Philippines. Introductions of aquatic organisms into Japan are controlled odly on the basis of the Convention on Intemational Trade in Endangered Species (CiTES) of Wild Fauna and Flora and the quarantine acts. Up to 1986 more than 120 exotic species have been introduced, of which only 36 were made prior to Introductions are classified into four basic categories. In this paper of those in two categories, (i) species which have spread widely over Japan and are self reproducing, and (ii) those which have been maintained for generations through artificial propagation or in confined natural waters are dealt with. Since the late 19th century, a great number of exotic species of aquatic organisms have been introduced into Japan primarily with a view to enrich the fish resources of the country. While the introduction of some of these species have caused serious ecological problems in natural waters, some others have been confined and cultured in aquaculture farms as market fish or well established in natural waters yielding new commodities of food or sports fishing without serious impact on the ecosystem. The evaluation of the transplantation of non-indigenous species can vary among people; an exotic fish species in a river or lake may be a acceptable game fish for anglers while it may be an enemy for fishermen who catch other species that are outrivalled by the newcomer. Moreover, we have to admit that the 'ecological sense' of the people vary in accordance with the cultural and socio-economic backgrounds of the country, even though conservation is the unanimous consensus of all nations. In any event, accumulation of accurate 63

75 64 information on the status of fauna and flora is essential to lay down effective ;chemes for controlling introduction of the species. The purpose of this paper is to give a brief historical review of the introduction of exotic species of aquatic animals in Japan and a brief description of the present status of these species. Species introduced as ornamental aquarium fish are excluded from this report. Review of Aquatic Species Introduced into Japan It is virtually impossible to trace all of the numerous aquatic organisms introduced into Japan over the last 100 years. However, efforts have been expended to collect distributional and ecological data on introduced exotic species by various institutions including the Fisheries Agency, prefectural fisheries stations and universities. The Environment Agency's on-going nation-wide survey of the distribution of freshwater fishes, which is carried out every 5 years, has also provided disributional information on the exotic species which have been naturalized in inland waters (Environmental Agency 1976, 1980, 1988). There has been no regulation to control the introduction of aquatic aninuls from an ecological standpoint. Animals brought in from abroad are checked only on the basis of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the municipal laws established in relation to the CITES, and the Quarantine Acts. Recently, FAO's program of the prevention of international epidemics was put into operation at the Fish Disease Center in Tokyo. According to Maruyama et al. (1987), more than 120 exotic species of aquatic animals have been brought to Japan up to Of these, only 36 species were introduced to Japan before Entering the postwar period, the number increased drastically, due largely to tile increasing demand for new commodities among commercial fishermen, aquaculturists and Sports fishermen and the development of transportation. Many of these species were introduced intentionally for stocking in the natural environment, commercial culture and/or sport fishing. Some species, such as the silver carp, Hypophthalmichthys molitrix and the bitterling, Rhodeous ocellatus ocellatus came to Japan accidentally; these two species arrived in Japan mixed with fry of the grass carp, Ctenopharyngodon idella (Nakamura 1955). Of the 120 species brought into Japan, about 9 species accounting for 7.5Vc of the total number have acclimatized themselves to the natural environment as self-reproducing populations; about 32 or 26.7% have been successfully bred; about 26 or 24.6% have disappeared; the status of about 53 or 4 1.2% remains obscure. In Table 1 they are classified into four categories; (1) species which have spread widely over Japan and are self-reproducing, (2) species which have been maintained for generations in captivity through spontaneou.s or artificial reproduction and/or established as self-reproducing populations in limited areas of natural waters, (3) species which are already extinct in Japan, and (4) species of which the present status cannot be elucidated. The following description by taxonomic group deals with only species which belong to categories 1 and 2 above and which are considered to have an economic or ecological importance.

76 65 Sa!monidae Examples of successful introduction of species for aquaculture are evident amongst salmonids, particularly the rainbow trout, Salmo gairdneri. Since its first introduction in 1877, many strains of rainbow trout have been imported from various localities of North America. This species is now the commonest species in cold-water aquaculture ponds in Japan and its annual production is maintained at 15,000-20,000 t. Programs of stocking of rainbow trout fingerlings in rivers have also been in operation in many areas since However, reproduction of the fish in natural waters has been confirmed only in Hokkaido (Kawanabe 1980). Other exotic salmonid species that are known to reproduce in natural waters are the brown trout, Salmo trutta and the brook trout, Salvelinusfontinalis. A number of species of the salmonid genus Core gonus have been introduced from East European countries for pond culture; still in experimental stages at research institutions and private farms. Core gonus species C. lavaretus maraena and C. peled among others are regarded as promising candidates for cold-water pond culture in Japan. Cyprinidae Four species of Chinese carps Ctenopharyngodon idella, Hypophthalmicht/jys molitrix, Aristichthys nobilis and Mylopharyngodon piceus are reported to reproduce in the Tone, one of the largest rivers in Japan (Inaba 1955), Though they are of no high commercial value, the former two species are of some importance in the commercial fisheries in the area. Because of their low trophic levels, there have been no reports indicating disturbances of river fauna because of these species. The bitterling Rhodeous ocellatus ocellatus is a small cyprinid occurring in continental East Asia accidentally introduced into Japan mixed with grass carp fry from China, and was first found in Japanese freshwaters in the mid-1940s (Nakamura 1955). Since then it has been expanding its distribution, most remarkably in the last decade, expelling the Japanese subspecies R. ocellatus smithi by ecological pressures and hybridization. R. ocellatus smithi is now on the brink of extinction as a distinct subspecies (Nagata and Nishiyama 1976). Atherinjdae The atherinid Odonthestes bonariensis, known as pejerrey in South America, was introduced into Japan from Argentina in 1966 as a species suitable for pond culture and stocking in lakes. It has turned out that the species can readily reproduce in captivity and the fish is now cultured at several fisheries stations and private farms. Seed has been stocked repeatedly in Lake Ashinoko and Lake Tsukui to create a new commodity of sport fishing, but it is not evident that the fish has adjusted itself in these lakes (Watase 1986). Centrarchjdae The North American bluegill, Lepomis macrochirus and largemouth bass Microprerus salmoides have readily established themselves in rivers and lakes and are spreading rapidly over

77 66 Table 1. List of exotic aquatic species (Status 1 - Established as self reproducing populations; Status 2 - being reproduced in certair. experunental or natural ponds; Status 3 - extinct at present; Status 4 - accurate information not available; UI, unintentional). Taxonomic Status Status From Introduced Year Remarks Pisces Acipenseridae Acipenser guldenstadti 3 USSR A.baeri 3 USSR 1964 Huso huso x USSR Acipenser ruihenus Clupeidae Alosa.capidissima 3 USA 1928/29 Anguillidae Anguillajaponica Korea China Taiwan 1964 A. anguilla 7 France Italy 7 England A. rostrata 7 Canada 1971(72 A. dieffenbachi and or 3 New A. australis Zealand A. bicolor pacfica 3 Philippines 1972 Elver foi commercial culture Elver for commercial culture Salmonidae Salmo gairdneri 2 USA trutta 2 USA S. salar 7 USSR 1980/83 Oncorynchus tshawytscha 7 USA O.nerka 7 Canada 1957? USA kisutch 2 USA 1965 Sal velinus naniaycush 2 Canada 1966/69 S.fontinalis 2 USA Core gonus lavaretu.r maraena 2 Czecho 1977/78 C. 1. ludoga 7 USSR 1981 C. autu,nnalis migralorius? USSR C. mukcun USSR 1981/83 C.peled 2 Czecho USSR C. clupeaformis 3 USA C. olbus 3 USA 1926/29 C. lavaretus baeri 3 USSR 1929/30 C. lavaretus maraena 3 USSR 1929/30 Cyprinidae Aristichthys nobilis 2 China Cienopharyngodon idellus 2 China Hypophthalmichthys molitrix 2 China Mylopharyngodon pi ce us 2 China Rhode us ocellaties ocellatus I China Tone River S. UI (mixed in grass carp fry) Tone River. S Tone River. S. Tone River. S. UI (mixed in grass carp fry) UT; Its Tapanese counterpartr. o. smithiis endangered by ecological pressure of and hybridization with this subspecies. Continued

78 67 Table 1. Continued Taxonomic Status Status From Introduced Year Remarks Cyprintss carpio ruscis 2 China 1971 Cyprinus carpio 2 Germany Cross bred 2 Austria Indonesia 1980 Cirrhina rnolitorella 7 China 1965/66 Megalobrama amblycephala 2 China 1978 Tinca tinca 2 Netherlands 1961 Carassius auratus gibellio 3 USSR 1930/64 Catla catla 3 India 1960 Pakistan 1970 Barbus for 3 India 1960 Labeo rohita 3 India 1960 Cirrhina rnrigala 3 India 1960 Ictaluridae Ictalurus punctaf us 2 USA 1971 Poeciliidae Gambussiaaffinis 1 Taiwan 1916 Atherinidae Odontesthes bonariensis 2 Argentine 1966 Percidae Percaflavescens 3 USA 1960 Centrachidae Lepomis macrochirus 1 USA 1960 Micropterus salnwides 1 USA 1925 Predation on native species Morone interrupla 3 USA 1960 Pomoxs nigromaculatus 3 USA Roccus saxatilis 3 USA Chichlidae Oreochromisaureus 2 Taiwan 1980 USA macrochir Syria USA mossarnbicus 2 Thailand Colonized polluted brackish waters around Okinawa Island. 0. urolepis hornorwn (reported as 2 Israel 1981 Tilapia macrocephala) 0. niloticus 2 Egypt 1962 Sarotherodon melanof heron 3 USA 1960 S.galilaeus 3 USA 1964 Tilapia sparrmanii 2 USA 1959 T. zulu 2 Egypt 1962 Belontiidae Macropodus chinenth 1 Korea 1914 Osphronemidae Osphronemus goramy 7 Thailand 1956 Scienidae Aplodinof us grunniens 3 USA 1960 Continue

79 68 Table 1. Continued Taxonomic Status Status From Introduced Year Remarks Channidae Channa argus 2 Korea 1923/24 Predatior on native species parasites C. maculata 1 Taiwan 1906/19 Parasites Crustacea Astacidae Pacfastacus leniusculus 2 USA 1909/29 Pond Tar kai in Shiga Pref. P. trowbridgii 2 USA 1928/30 Lake Mashu in Hokkaido Proca,mbarus clarkii 1 USA 1930 Parastacidae Cherax tenuimanus 3 Australia Nephropsidae HomarusAmericanus 7 USA Penaeidae Penaeus chinensis 7 Yellow Sea Palaemonidae Macrobrachiu.m rosenbergii 2 Malaysia Thailand USA (Hawaii) Mollusca Unionidae Lamprotula (Quadrula) bazini 3 China 1917 Lampsilis luteola 3 USA 1926 Anodonta woodiana 3 Taiwan 1962 Mytiidae Mytilus edulis galloprovincialis 1 7 ca.1926 UI Ostreidae Ostrea lurida 2 USA 1948 O.eduh.c 2 France 1952 Crassostrea angulata 7 France 1952 C.virginica 7 USA 1968 Haliotidae Haliotis rufescens 2 USA 1966 Ampullaridae Pila leoporavillensis x Ampullarium insciarum 1 Taiwan 1981 Hybrid; it is unknown whether pure strains have have been introduced or not

80 the Japanese main islands. After its first introduction into Lake Ashinoko in 1925 for lure fishing (Akaboshi 1959) and an initial unsuccessful attempt of its transplantation into several other lakes, transplantation of M. salmoides from Lake Ashinoko to other waters was prohibited to prevent possible destruction of local fish fauna by this predaceous species. However, the attraction of this fish as a game for lure fishing has led some indiscreet anglers to secretly transplant it into many lakes. This resulted in its subsequent rapid dispersal over Japan and its predation on many native fish species. The impact of the largemouth bass on indigenous fish fauna appears to vary particularly in relation to the depth of water (Nomura and Furuta 1977). The predation on indigenous fish by largemouth bass has caused serious problems in shallow waters and efforts to eradicate this predator have not been successful (Kikukawa 1980). In deep waters such as Lake Ashinoko, largemouth bass coexist with native fish by habitat segregation. 69 Cichlidae Nine species of tilapia have been introduced into Japan for the purpose of pond culture utilizing heat from hot springs or cooling-water discharge from power plants or factories. Of these species, Oreochromis niloticus is enjoying a comparatively high reputation as a food fish, with its annual production reaching more than 5,000 t in 1985 (Maruyama 1986). 0. niloticus, 0. mossambicus, Tilapia sparmanii and T. zulu have colonized estuarine waters in the Okinawa Islands (Imai 1980). Changes in the Japanese Freshwater Fish Fauna The freshwater fish fauna of Japan has been changing rather conspicuously in recent years. The freshwater fauna is originally rich in southwestern Japan and comparatively poor in northeastern Japan. The recent changes in freshwater fish fauna are characterized primarily by the dispersal of many species endemic or indigenous to southwestern and northeastern Japan. This northeastward dispersal is considered to be attributable largely to the transplantation of a species called "ayu from Lake Biwa in central Honshu. Though this has little to do with the introduction of exotic species, we believe it worthwhile to briefly mention of what is going on in the Japanese freshwater fish fauna. Ayu, Plecoglossus altivelis, a small, annual fish closely related to salmonids is one of the favourite game fish and an inland water delicacy among the Japanese. Young and sub-adult ayu inhabit the middle to upper reaches of clear water rivers and reach maturity as they descend to the lower reaches where they spawn. Larvae migrate to the sea and juvenile ayu ascend rivers after spending the whole winter in the sea. Due to obstructions on the migration route by dams and other structures, fry of ayu are being released into upstream areas all over Japan in large numbers every year. The majority of the fry released are collected from Lake Biwa where a landlocked population of ayu abounds. This stocking activity is certainly a boon to more than 10 million amateur anglers who enjoy ayu fishing. However, it has created a side-effect; colonization of the inland waters of northeastern Japan by species that had been found only in southeastern Japan. It is widely accepted that the dispersal of southwestern elements has caused by incidental transportation of fry of many species mixed in ayu seed collected from Lake Biwa. These immigrants include a few carnivorous cyprinids and the predaceous largemouth bass.

81 70 From this historical review, it can be seen that the introduction of aquatic species into Japan is closely related to the development of transportation. Before the World War II, shipping was the only mode of transportation live species from foreign countries to Japan. It was difficult for private enterprises to introduce live aquatic species from foreign countries because of shipping costs. Therefore, only the national and/or local governments were able to introduce the aquatic species from other countries for productive increase of animal protein. As the target species were selected by the government authority itself, rules governing introduction of aquatic species were not thought to be necessary. Entering the postwar period, the development of transportation drastically increased the number of species introduced from other countries; they are not only used in pond culture, but also as ornamental pet fish in aquariums. Critical changes in fauna and flora caused by exotic species have never been observed as a result of unrestricted introduction of aquatic species. However, some changes, as mentioned above, have already been reported. Those re Rhodeus ocellatus smithi being replaced by R. o. ocellatus, colonization of northeastern Japan by nativeborn species found in southwestern Japan, and the predation of largemouth bass Micropterus salmoides on many native fish species in certain places. These situations should be considered as a warning alarm for unrestricted introduction of aquatic species and the need for deliberation and care for further introduction of aquatic species in Japan. References Akaboshi, T Blackbass. Miyazaki-ken Tansui-gyogyos hidojyo, p Environmental Agency Dai 1 kai shizen kankyo hozen kisochosa houkokusho (Report of the first national surveys on the natural environment). Shakai-chosa- kenkyusho. Tokyo, Japan. Environmental Agency Dai 2 kai shizen kankyo hozen kisochosa houkokusho (Report of the second national surveys on the natural environment). Shakai-chosa- kenkyusho. Tokyo, Japan. Environmental Agency, Dai 3 kai shizen kankyo hozen kisochosa houkokusho (Report of the third national surveys on the natural environment). Shakai-chosa-kenkyusho. Tokyo, Japan. Imai, S Tilapia in Nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawai et al., Tokaidaigaku-shuppankai. Tokyo, Japan, p Inaba, D Tonegawa niokem sogyo no hanshyoku (Re producti on of the Chinese Carp in the Tone River). Zenkoku-kosh.D--kasen yoshoku kenku-kai-yohou. Kawanabe, H Nijimasu (Rainbow Trout) in" Nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawai et al., Tokaidaigaku-shuppankai. Tokyo, Japan, p Kikukawa, Y Blackbass in"nihon no Tansuiseibutsu (Freshwater aquatic species in Japan)". Edited by T. Kawai et Si., Tokaidaigakushuppankai. Tokyo, Japan. p Maruyama. T.K., T. Fuji, Kijima and H. Macda Gaikokusan shingyoshu no donyu keika. (Introducing process of extic species from foreign countries). Fisheries Agency, Tokyo. Nagata, Y. and K. Nishiyama Remarks on the characteristics of the fins of bitterling. Rhodeus ocellatus ocellatus (Knen and R. ocellatus smithi (Regan). Memoirs of the Osaka Kyoikyu University Series ifi 25(1): Nakamura, M Kanto-heiyani shutsugenshita ishyokugo (Some exotic fishes appeared at the Kanto Plains). Nihon-seibuisu-chiri-gakkaiho 16/19: Nomura, M. and Y. Furuta Gunma-ken niokem koshyo kasen no koudo gyogyou-riyou ni-kansuru chyosha-hokokushyo. Gunma Prefecture, p Watase, S Pejerrey in" Shingao no sakan (New aquatic species in Japan)". Seizando. Tokyo, Japan.

82 The Status of Introduced Fish Species in Malaysia K.J. ANG Faculty of Fisheries and Marine Sciences Universiti Pertanian Malaysia Serdang, Selangor R. GOPINATH Department of Fisheries TKT 8 Wisma Tani, Jin. Mahameru Kuala Lumpur, Malaysia T.E. CHUA International Center for Living Aquatic Resources Management MC P.O. Box 1501 Makati, Metro Manila Philippines Ang, KJ., R. Gopinath and T.E. Chua The Status of introduced fish species in Malaysia, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. The fate of introduced fish in Malaysia was traced with special reference to their abilities to establish in local conditions. Of the dozen food fish introduced into Malaysia, only Trichogasser pectoral is, Punt ius gonionotus, tilapias and Clarias macrocephalus were able to establish successfully. Other species were able to grow well in local environment but were not able to propagate naturally. Introduced fishes contribute 88% to total freshwater aquaculture production and 72% to total freshwater fish production. Some diseases found with introduced fish are recorded. Existing laws governing importation of exotic species are examined. The term "exotic" species has been defined as the introduction of an organism by man from a foreign country outside the native range of that species (Kohier and Stanley 1984; Kohler 1986). The same authors defined "introduced" aquatic species as a plant or animal moved from one place to another by humans (i.e., an individual, group or population of organisms that occurs in a particular locale as a result of human intervention). These two terms have been used loosely. For the purpose of this paper, the term "introduced" is used to include species introduced from foreign countries also. Malaysia is endowed with a tropical climate, productive marine and terrestial ecosystems, and great species diversity. A large number of fish species has been recorded (Scott 1959; Johnson 1961; Chua 1978; Mohsin and Ambak 1983). Many are commercially important and most have been heavily exploited. Many species were introduced to Malaysia in the early 19th century either by Chinese immigrants for sentimental reasons or by fisheries officials trying to provide development of 71

83 72 what they perceived as economically useful species. Species introductions have never been a major government thrust because of the availability and abundance of indigenous species. The main concerns about the fish introductions are the risks associated with any one or all of the following problems as listed by Welcomme (1986): - contamination of existing natural communities with foreign species, - the introduction of disease, - the direct disruption of the fish community through competition or predation, the genetic degradation of the host stock, the degradation of the environment by the introduced species, and - the disruption of human lifestyles, customs or economic systems. It is difficult to find a country in Asia whose natural fish communities are not contaminated by introduced species. The risks of disease transfer, genetic and environmental degradation as well as disruption to the natural fish communities can, however, be reduced if not prevented if appropriate precautionary measures are observed. The objectives of this paper are to trace the fate of introduced fish in Malaysia and to assess their possible ecological or biological impact. Fate of Introduced Species Available records show that fish introductions in Malaysia were initiated in the early 19th century along with the immigration of the southern Chinese who brought along the techniques of fish farming. Fingerlings of grass carp (Ctenopharyngodon ide/la), bighead carp (Aristichthys nobilis), silver carp (Hypophthalmichthys molitrix) and common carp (Cyprinus carpio) (Welcomme 1981; Mohsin and Ambak 1983) were raised in mud ponds and unused mining poois. The snakeskin gouramy (Trichogaster pectoralis) was introduced either in the late nineteenth or early twentieth century and established itself in paddy fields, irrigation canals and freshwater swamps, forming an important fishery. After World War II, a few more species were introduced by the Department of Fisheries, private organizations and individuals. Tilapia (Oreochromis mossambicus) was introduced in 1944 from Java. This species rapidly established itself in freshwater as well as in brackish water. In 1979, 0. niloticus was introduced from Thailand and in 1980, red tilapia hybrids were brought in from Taiwan. These two species/varieties are of better quality for aquaculture purposes and they are now popularly cultured in freshwater ponds and mining pools. In the 1L950's catfish (Clarias macrocephalus) was introduced and soon became a strong competitor with indigenous species (Clarias batrachus). The Javanese carp, Puntius gonionotus, was successfully introduced into Malaysia in 1958 (Table 1). The Department of Fisheries also introduced the Indian major carps in the 1960's, particularly catla (Catla catla), mrigal (Cirrhina mrigala) and rohu (Labeo rohita). Like most Chinese carps, these species do not breed in captivity under local conditions. Their culture is dependent on imported fingerling supply. Etroplus suratensis was introduced in 1975 from Sri

84 Lanka into Sarawak and Sabah. The slow growth rate makes it noncompetitive with other fastgrowing species for aquaculture. Besides food fishes, recreational fish species were also introduced. The rainbow trout (Salmo gairdneri) was introduced into the mountain streams of Brinchang, Cameron Highlands in 1935 from Scotland; in 1968, Boh Tea Plantation introduced the same species in Tanah Rata, Cameron Highlands, from New Zealand. In both cases, there was no evidence of breeding although the trout grow to about 750 g. Growth of the domestic and international ornamental fish trade in recent years has greatly promoted extensive importation of freshwater and marine species from all parts of the world. A variety of such species can be seen in most retail aquarium shops (Table 2). Some of the small species such as Poecilia reticulatus and Gambusia affinis introduced for controlling the spread of mosquitoes have now established themselves extensively in many organically rich water bodies. Other species introduced as ornamental fish include the Siamese fighting fish (Betta splendens), the sucker catfish (Plecostomus punctatus) and the molly (Molliniesa sp.) have also established themselves in freshwater ponds and pools (Table 2). The angelfish (Pterophylum scalare), and the Oscar (Atronotus occelatus), have been found to breed naturally in ponds (Ang, unpublished data). Despite the large number of exotic species introduced as ornamental fish in Malaysia, only a few have become successfully established in natural water bodies (Johnson 1963). 73 Snakeskin gouramy Performance of Introduced Species The snakeskin gouramy was reported by Soong (1948) to have been first introduced into Malaysia in According to Green (1926) it was introduced in the late nineteenth century. Both authorities agree that the transfer was first made in the Krian rice-bowl area, northwestern Peninsula Malaysia. Today it is found widely distributed in swamps, rice fields and irrigation canals throughout the country (Mohsin and Ambak 1983). The Krian rice-bowl area at one time supported a very substantial rice-field fishery. based almost exclusively on the snakeskin gouramy (Merican and Soong 1966). Due to the double cropping of rice and the wide use of pesticides, the snakeskin gourami fishery has been drastically reduced (Tan et al. 1973). The total production from ponds was only 107.5t in 1986 (Table 3). It is difficult to gauge the impact this species has had on the environment. Soong (1948) maintained that this species has had no deleterious effect on other rice-field fishes, especially the climbing perch (Anabas testudineus), the snakehead (Channa striata) and catfish (Clarias spp.). However, it is certain that the indigenous Trichogaster trichopterus has been displaced, at least to some extent, since both have similar feeding habits and occupy the same niche in the paddy field ecosystem. Chinese Major Carps and Common Carp Chinese major carps (grass carp, bighead carp, silver carp and mud carp) and common carp, were introduced into Malaysia in the early part of the nineteenth century by Chinese migrants.

85 74 Table 1. Fate of the introduced foodfish in Malaysia. Species Introduced Established Current Status Remarks From Year (reference) OSPHRONEMIDAE Trichogaster peer oralis CICHLIDAE Oreochromis mossambicus 0. niloticus Red tilapia hybrids Etroplus suratensis CLARI[DAE Clarias,nacrocephalus CYPRNTDAE Puntius gonionot 555 Ctenopharyngodon idella Aristichihys nobilis Hypophthalmichthys molitrix Cyprinus carpio Indian major carps (Catla catla Labeo rohita, Cirrhina mrigala) Thailand, 1921 (Soong 1948) Java, Indonesia, 1944 (Mohsin & Ambak 1983) Thailand, 1979 Taiwan 1980, Thailand 1981, Sri Lanka 1975 (Welcomme 1981) Thailand, 1950 (Tweedie 1952) Indonesia, 1958 (Welcomme 1981) China, Early 19th century (Welcomme 198 1) China, early 19th century (Welcomme 1981) China, early 19th century (Welcomme 1981) China, early 19th century (Welcomme 1981) Introduced from India in 1960 Paddy fields, swamps, canals Ponds, canals, tin mining pools, streams ponds, reservoir mining pools Ponds Ponds Ponds, swamps Rivers, ponds, mining pools Important pond cultured species. Attained 2-3 kg in6months Doesnot breed in pond or captivity. Fry imported from Taiwan or Hongkong. Parasites are Chloromyxurn lageri, Sanguznicola armata, Argsdus (Faizxh 1986) Cultured in ponds and mining pools. Does not breed in captivity. Common parasites are Dictylogyrue, Trichodina, Chilodonella (Shariff and Sommerville 1986; Faizah 1986) Cultured in ponds Ponds and tin mining pools Ponds cultured in paddy fields; yield of kg/ha (Tan et al. 1973); sell reproducing population Self reproducing population in fresh and brackish water, prolific breeder and stunted growth mono or polycultured in ponds and cages; reach gin 4 months Cultured in ponds introduced in ponds in Sarawak Cultured in ponds and paddy fields Polycultured in pond Polycultured in ponds; minor species for aquaculture Do not breed in natural habitats Badly hit by double cropping of rice and use of pesticides; infected with hemorrhagic septicaemis; displaced so some extent, the native species, T. trichopieru.s This species is rarely cultures. now Self reproducing in pools Breeds also in brackishwater p)nds Breed üi natural habitats Breed in local waters Not popular in Malaysia SALMOMDAE Salmo gairdneri Micropterus salmoides Scotland, 1935 New Zealand, 1968 Florida, 1984 by Boh Tea Plantation, Cameron Highlands Introduced in stream and lakes in Cameron Highlands as sport fish. Grow to 750 g. No breeding reported. Stocking terminated in 1973 for economic reasons Stocked in ponds used for trout earlier Reported the presence of fry in ponds but none were found downstream. CHARACIDAE Colossoma sp. Taiwan, 1984 Ponds Cultured in ponds, Subsequently the Dept. attained fast growth Fisheries banned it because its fry resemble those of piranhas

86 75 Table 2. Ornamental fishes recorded in Malaysia. Scientific Name Common Name Origin/Source Abramites macrocephaliss Headstander Amazon/Singapore Aequiden pukher Blue acara Colombia/Singapore Apistogra.mina ramizeri Butterfly cichlid Venezuela/Local Astronottes ocellatus Oscar Amazon/Local Betta splendens Siamese fighter Thailand/Local Botia nacracanthus Clown bach Indonesia/Thailand Carassius auratiss Goldfish China/Local Cichiasoma meeki Fire mouth Guatamala/Singapore Colisa latia Dwarf gouramy India/Local Danio malabaricus Giant danio Sri Lanka/Singapore Gnat honemus petersi Elephant nose CameroonlSingapore Gy,nnocorymbus ternetzi Black tetra Paraguay/Singapore Hyphessobrycon callistus serpae Serpae tetra Amazon H. innesi Neon tetra Amazonlllongkong H. pulchripinnis Lemon terra South America/Local Singapore/Hongkong Kryptoteriss bicirrhis Glass catfish Local and Thailand Labeo bicolor Red-tail black shark Thailand L. erythrura Red-finned shark Thailand Leptobarbus hovenii River carp Local/Indonesia Thailand Metynnis sp. Silver dollar Amazon/Singapore Puntius oligolepis Checker barb Singapore P. scubert Golden barb China Plecostomus punctatus Sucker catfish Singapore Poecelia reticulata Guppy Venezuela/Brazil Singapore Moiliniesa latipina Sailfin molly Local and Singapore Puntius conchonuis Rosy barb Singapore Pterophylwn eimekei Angelfish Local P. scalare Angelfish Local Scieropagesformosus Dragonfish Local/Indonesia/ Thailand Osleoglossum Syenphysodon spp. Discus Local Trichogaster leeri Pearl gouramy Local, Thailand T. trichoplerus sumatranus Opaline gouramy Xiphophorus helleri Swordtail Local/Singapore X.,waculatsss Platy Singapore Note: The term source is used here where fish were obtained. It does not denote local occurrences. Table 3. Production of introduced fish species in ponds at Peninsular Malaysia in (Soutce: Annual Fisheries Statistics, 1986). Common Name Species Production (t) Javanese carp Puntius gonionotus Common carp Cyprinus carpio Grass carp Ctenopharyngodon idella 1,516.4 Bighead carp Aristichthys nobilis Tilapia Oreochromis spp Snakeskin gourami Trichogasterpectoralts TOTAL 4,158.0 Total freshwater production (ponds & wild) 5,753 Total freshwater fish production by aquaculture 4,709

87 76 While it is likely that at the onset, all these species were cultured (Birtwhistle 1931), local market preferences gravitated towards grass carp, bighead carp and common carp. Silver carp and mud carp have little commercial value and are not popularly cultured. None of the Chinese major carps breed naturally in captivity and have neve] established themselves in local waters. Public stocking programs involving grass carp were first carried out in the Bukit Merah and Cenderoh impoundments in the early 1960's. Though sporadic reports of adults of 11 kg being caught were reported, results on the whole were not encouraging (FAO 1965). Bighead carp fingerlings were stocked in the Durian Tunggal, Paya Nakoh and Ampang reservoirs. The absence of catch data prevents meaningful assessments of the introduction. On the whole, the release of common carp fry into public waters has been avoided because of their scouring habits which weaken bunds and increase water turbidity. Common c arp has not established itself to any major extent. The Chinese carps constitute the mainstay of Malaysia's freshwater aquaculture industry. In 1986, grass carp, bighead carp and common carp contributed 53.3% by weight and 48.7% by value of Peninsular Malaysia's freshwater aquaculture harvest (Table 3; Annual Fisheries Statistics 1986). Rainbow Trout Rainbow trout (Salmo gairdneri) was first introduced in Brinchang, Cameron Highlands in Eyed ova, imported from Scotland, were hatched in a now-abandoned facility and the fingerlings released in the Tenom River. No details are available on the numbers released, nor how they fared in the new ecosystem. However, there were unconfirmed reports from villagers living in the area that berried females weighing about 750 g could be caught from the same river (Somasekheran, pers. comm.). The program ceased during World War II. In 1968, Boh Plantations Limited, a tea company in Tanah Rata (also in Cameron Highlands), began a trgut project for recreational purposes. Fingerlings were released in three lakes, each of about 3 ha. However, no reliable records on numbers released and. catch were made. Mature females were frequently caught, but there was no evidence that the fish bred in local waters. Indeed, maintenance of fish stocks necessitated regular releases of trout fingerlings. The project was terminated in 1973 mainly for economic reasons. Significantly, disease problems (whirling disease) in the hatchery were a major impediment to the continuation of the project. Tilapia Tilapia, Oreochromis mossambicus, was first introduced into Malaysian waters from Java by the Japanese during World War II. O.mossambicus rapidly established itself, particularly in mining pools, impoundments, and even some coastal areas such as the Johore Straits, bordering Singapore and Malaysia. 0. mossambicus was initially well received by farmers. In the 1950's it was actively cultured in ponds and mining pools throughout the country. However, its frequency of reproduction meant that adults did not grow beyond 200 g. While fish production per unit area was high they consisted of stunted individuals with little marketability. The fish was also difficult to eradicate from ponds, particularly undrained ponds and competed with preferred

88 species for food and space, again leading to poor growth, this time among other species of fish. By the early 1960's, tilapia began to be regarded as a nuisance. In a bid to overcome problems inherent in 0. mossambicus culture, attempts were made to develop all-male hybrids. Hickling (1960) experimented on hybridization and as a result of his experiments Oreochromis niloticus, 0. hornorum, Tilapia zulu and T. rendalli were introduced into Malaysia. He was successful in obtaining an all-male hybrid (0. mossambicus x 0. hornorum), but it did not find lasting commercial success in Malaysia. This is because hybrids were contaminated by stray 0. mossambicus. In 1972, the Department of Fisheries officially ceased all production of 0. mossambicus in its hatcheries. A policy of discouraging its culture was also instituted. The policy was revised only in 1975, with the recognition of 0. niloticus as an acceptable alternative. While 0. niloticus was originally brought into Malaysia in the 1960's, pure lines were not maintained. Therefore, in 1979 a stock of pure 0. niloticus consisting of 400 individuals was imported from Chengmai, Thailand, and raised in the Department of Fisheries hatchery of Jitra, Kedah. This stock constituted the broodstock for all the Department hatcheries to the present. The Department of Fisheries first imported six red tilapia from Thailand in A second importation consisting of 500 individuals was made from Thailand in the same year. In 1982, a stock of red hybrids was imported from Taiwan and maintained in the Freshwater Fisheries Center, Bukit Tinggi, to prevent interbreeding with wild stock or with each other. Red tilapia found a lucrative urban market, and before long commercial culture of red tilapia started. However, soon demand outstripped production by 12.7% in 1983, 22.5% in 1984, 24.7% in 1985 and 19.6% in The industry was also very substantially different from the one that raised 0. mossambicus thirty years earlier. Tilapia was then raised by small farmers in ponds and mining pools using semi-intensive and extensive methods. The red tilapia, while still relying substantially on such methods, saw the proliferation of commercial, intensively operated farms using formulated feeds and high rates of water exchange. Markets have also changed. Where 0. mossambicus was sold fresh at the wet markets, red tilapia is consigned mainly to the restaurant trade which demands live fish. Live red tilapia is also sold in specific supermarkets under the name red snapper or cherry snapper. There is little documented evidence of impact of the tilapia in Malaysian waters. The proliferation of 0. mossambicus particularly in mining pools and lakes, is generally recognized as having affected local icthyofaunal populations but the species affected and extent to which they have been affected is not documented. The massive importation of red tilapia fry may have brought in non-indigenous epizootics. A lack of suitable baseline information on the fish disease status of the country however, prevents any meaningful comparisons. Red tilapia (particularly those not treated for monosexuality) are no less prolific than 0. mossambicus. It is no longer uncommon to see mining pools filled with red tilapia fry and stunted red fish. These fry have undoubtedly escaped into rivers and streams, where they proliferate, breeding either with themselves or with wild 0. mossambicus stock. At this point in time, red tilapia have yet to match the widespread distribution of 0. mossambicus. Whether they will or not is an open question and will depend on their hardiness and their capability to compete with resident animals. 77

89 78 Pearl Spot The pearl spot, Etroplus suratensis, which is a brackishwater cichlid found in India and Sri Lanka (Ong 1983) was introduced to Sarawak, Malaysia from Sri Lanka in 1975 (Welcomme 1981). The species breeds readily in freshwater or brackishwater, in ponds. They, however, are not found in large quantities in natural bodies of water. Catfishes The catfish Clarias macrocephalus was introduced in 1950 from Thailand (Tweedie, 1952) and has been able to propagate in swampy ditches and is also found in paddy fields and pools. It can be cultured in ponds. Although they can breed naturally in swampy areas, they have not been able to compete with the indigenous catfish, Clarias batrachus. Javanese Carp The Javanese carp, Puntius gonionotus, locally called Lampam Java, was first Fitroduced in 1953 (Welcomme 1981). Stock obtained from Indonesia was raised in the Tahpah Fish Breeding Center in Perak (Somasekheran, pers. comm.). In the late 1960's further introductions of P. gonionotus stock, this time from Thailand, were made. The fish was bred with existing broodstock and the progeny were distributed among the Department's five breeding stations. The last importation of P. gonionotus stock was from Indonesia (Soong 1963). Javanese carp is one of the most popular cultured fish in Malaysia. In 1986, some 969 t of fish were raised by fish farmers amounting to a total wholesale value of M$ :2.76 Million, ranking second after the Chinese major carps in the freshwater aquaculture industry (Table 3). However, while Chinese major carps are raised by commercial fish farmers, the Javanese carp is highly preferred by subsistence farmers. It is also the primary species involved in the Department of Fisheries open-water stocking program since the 1960's. The importance of the Javanese carp is underscored by the production figures of Government freshwater breeding centers. The release of Javanese carp in public waters over the last 20 years has established this species as part of the Malaysian icthyofauna. The fish is caught by subsistence fishermen mainly to supplement domestic requirements. There is however, no commercial fishery. As with other fish, it is very difficult to evaluate the environmental impact of the Javanese carp. There is no evidence that the Javanese carp has displaced any indigenous puntid species. Indian Major Carps The Indian major carps, i.e., catla, rohu and mrigal were imported from Calcutta in 1960 and raised in the Tapah Fish Breeding Station (Welcomme, 1981). Part of this stock was removed to the Freshwater Fisheries.Research Station at Malacca. The culture of the Indian major carps has not proved popular. However, rohu is still cultured in the states of Negeri Sembilan and Malacca to a limited extent. Rohu fry are also produced on an ad hoc basis by the Freshwa:er Fisheries Research Station in Malacca and are consigned entirely to the open water stocking program.

90 The Indian major carps, in common with Chinese major carps, do not breed naturally under local conditions. That, coupled with the fact that distribution of fry has been limited, has meant that these carps have not had any significant biological or ecological impacts on the local fish fauna. 79 Pacu The Pacu (Colossoma sp.) was introduced to Malaysia about It was the first South American fish to be cultured locally. The main focus of this culture activity was the Ulu Kelang area. However, the Department of Fisheries subsequently banned the fish because its fry could not be distinguished from the piranha, Serrasalmus and Rooseveltiella. Black Bass Micropterus salmoides represents the latest introduction in Malaysian waters. The fish was imported by Boh Plantations Ltd. in 1984 as an attempt to revive their recreational program. About 1,000 fry were imported from Florida and raised in the Boh hatchery to fingerling size before being released in two lakes each about 3 ha in size. The lakes were the same water bodies that accommodated trout 10 years previously. Angling was permitted after one year. Mature adults weighing about g were caught. However, there has been no reports of the same fish downstream of the lakes, and one can assume that bass is so far restricted to the lakes. Problems of Disease and Parasites from Introduced Species The problem of introducing diseases into the local fish fauna can be a serious one. Such introductions may come through the importation of food fishes and ornamental fishes into the country. At the moment there are no procedures to examine and ensure that all imported live fish are free from disease. Shariff and Vijiarungam (1986) and Shariff and Sommerville (1986) have reported the occurrence of parasites in the freshwater fishes of Malaysia. Their findings are summarized in Table 4. Shariff and Sommerville (1986) remarked that the free flow of infected fish from the breeding stations and the importing agency resulted in the spread of Lernaea in Peninsular Malaysia. Shariff (1980) also indicated that Lernaea was brought into the country probably through exotic ornamental fish. Existing Policies and Regulations on Introduction of Exotic Species into Malaysia While State enactment has existed from colonial times (F.M.S. Enactment No. 20 of 1937; Kedah Enactment No. 40; Kelantan Enactment No. 32 of 1939; Perlis Enactment of 1334;

91 80 Trengganu Enactment No. 8 of 1963; Sarawak Ordinance Cap. 73), the firsi: Federally constituted statute covering the fisheries sector came only with the Fisheries Act Under Section 21(K), the Act empowers the Minister of Agriculture to "prohibit or control the importation into, or the sale, cultivation or keeping in West Malaysia of live fish or any particular species of fish which are not natives of West Malaysia and in Sabah andl Sarawak of live fish or any particular species of fish which are not natives of Sabah and Sarawak'. In 1973, the Minister announced the prohibition of import of Piranhas (Serrasa!mus sp.) in the states of West Malaysia and East Malaysia except with the written permission of the Minister. This regulation was extended to cover piranhas of all genera including pacu whose adult or fry resemble the dangerous Serrasalmus or Rooseveltiella. In 1984, a new Act, the Fisheries Act 1984, was passed to replace the aging earlier act. The new act is more embracing than the earlier act. Under Section 40(1), "anybody who imports into or exports out of Malaysia or transports live fish from West Malaysia to Labuan or Sabah and Sarawak, or transports from Labraun or Sabah and Sarawak to West Malaysia without a permit or violates any condition on a permit issued by the Director-General of Fisheries under this Act is guilty of an offence." Section 40(2) in the same Act reads as follows:- "The Director-General may lay down any condition that is considered necessary on the permit, including conditions pertaining to the sanitation of the fish that is to b exported, imported or transported and measures to avoid the spread of communicable disease or to avoid or to control release of non-indigenous fish in the environment." In 1987, Malaysia ratified its inclusion in the Convention of International Trade in Endangered Species (CITES), a move that automatically stopped all imports of species listed in IUCN's Red Book. Most affected by this was the aquarium fish trade, in particular the importation of Scieropages formoses, a popular aquarium species which is imported from Thailand and Indonesia to meet the local demand. Trade in other fish, particular:[y the South American equivalent of Scieropages, the arawana (Osteoglossum bicirrhosum), was also affected. The Government is also committed to setting up a comprehensive quarantine network to control the entry of exotic epizootics. Section 40(2) of the Fisheries Act 1984 was, in fact, framed with such a view in mind. Quarantine centers will be set up over the next five years in five major entry points. These centers will mitigate to some extent any negative impact of introductions, besides serving to enforce import regulations of these species. Conclusions The dearth of literature makes it very difficult to accurately assess the biological impact of food fish species introduced into Malaysia in the past seven decades and the large number of exotic ornamental species imported very recently. However, information available indicates that the introduction of Chinese carps, Indian major carps, rainbow trout and black bass have very little visible ecological impact on the freshwater ecosystem. This is partly because of their inability to reproduce in natural water bodies. However, a few species such as Trichogaster pectoralis, tilapias, Puntius gonionotus and C/arias macrocep ha/us have successfully established in Malaysian freshwater habitats. There is no negative impact of introduced species on human life-styles, customs or economic systems. In fact, some introduced food fishes such as Chinese carps and the snakeskin

92 gouramy have positive economic impacts as well as nutritional contribution to rural communities. Similarly, the ornamental fish trade has grown considerably from US$ 100,000 in 1973 to the current value of US$ 4 million (New Straits Times, 21st January 1988). There is still potential to increase the ornamental fish trade to US$ 32 million of the US$ 4 billion world wide trade (Ang, unpublished data). Present economic benefits derived from ornamental fish trade and introduced food fish should not be used to justify indiscriminate introduction without considering the risks associated with introductions. Every effort should be made to reduce the risks by appropriate quarantine procedures. Malaysia's inclusion in the convention of International Trade on Endangered Species (CITES) is a useful step in this direction. The revised Fisheries Act and Government efforts to establish quarantine stations to monitor imported species are welcome moves. 81 Table 4. List of parasites and their hosts at the freshwater breeding stations in peninsular Malaysia. Station Host Parasites Enggor Tanah Rata Machang Bukit Tinggi Tapah Jitra Kong Kong Cyprinus carpio Trichogaster pectoralis Tilapia sp. Puntius gonionotus Cyprinus carpio Cyprinu.s carpio Ctenopharyngodon idella Puntius gonionotus Aristichihys nobilis Puntius gonionotsls Cypriniu.s carpio Puntius gonionotlis Cyprinus carpio Hetostoma temmincki Cyprinus carpio Tilapia sp. Tilapia sp. Puntius goni000tus Cyprinus carpio Monogenetic trematode, Lernaea cyprinacea Piscinoodiniu,n sp., Trichodina sp. Trichodina sp. Monogenetic trematode Trichodina sp., Piscinoodiniwn sp. Monogenetic trematode, Trichodina sp., Myxobolus sp., Lernaea cyprinacea, Argulus japonicus Monogenetic trematode Trichodina, Lernaea cyprinacea Trichodina sp., Monogenetic trematode Lernaea cyprinacea Lernaea cyprinacea, Lernaea piscinae, Monogenetic trematode Lernaea cyprinacea, Trichodina sp., id hyopht hirius mu11fihiis., Piscinoodium sp. Monogenetic trematodes Trichodina sp., icthyophthiriu.s mutt ijiliis, Lernaea cyprinacea, Monogenetic trematode, Piscinoodium sp. icthyophlhiriu.s mutt fihiis, Argu!usjaponicus, Piscinoodiu,n sp. Monogenetic trematode, Lernaea cyprinacea Lernaea cyprinacea, Trichodi,za sp. Monogenetic trematode, Piscinbodiu,n sp. Trichonida sp., icthyophthirius nzuttiflhiis Lernaea cyprinacea, Monogenetic trematode Lernaea cyprinacea, Monogenetic trematode

93 82 References Annual Fisheries Statistics Department of Fisheries, Malaysia. Birtwhistle, W Rearing of carps in ponds. Malayan Agricultural Journal 19(8): Chua, C.W Commercial prawns of Peninsular Malaysia. Ministry of Agriculture, Kuala Lumpur, 48 p. Faizah Mohd, Shaharom The parasites of bighead carp (Aristichthys nobilis) and grass carp (CIe,wpharyngodon idella) from Peninsular Malaysia, p In MJ. Howell (ed.) Handbook of Sixth International Congress of Parasitology. Australian Academy of Science. FAMA Harga barangan pertanian Tahunan. Federal Agricultural Marketing Authority, Kuala Lumpur. (unpublished data). FAQ Report to Government of Malaysia. Development of inland fisheries with special emphasis on fish culture. FAO Prcject MALITEIF1. Report No Green, CF Fish Culture. Annual Report of the Fisheries Department. SS & F.M.S. Hickling, C.F The Malacca tilapia hybrids. Journal of Genetics 37(1). Johnson, D.S Freshwater life in Malaya and its conservation. Malayan National Journal, Special Issue, Johnson, D.S The fate of introduced fish in Malaya. Proc. XVI International Conference of Zoology, Washington, I).C. August 20-27, p Kohler, L.C Strategies for reducing risks from introduction of aquatic organisms. Fisheries 11(2): 2-3. Kohler, L.C. and J.G. Stanley A suggested protocol for evaluating proposed exotic fish introductions in the United States, p In W.R. Courtenay and JR. Stauffer (eds.). Distribution, Biology and Management of Exotic Fishes. The John Hopkins University Press, Baltimore, MD. Merican, A.B.O. and M.K. Soong The present status of freshwater fish culture in Malaysia. Paper presented at FAQ World Symposium on Warm-water Pond Fish Culture, Rome, Italy, May p. Mohsin, A.K.M. and M.A. Ambak Freshwater fishes of Peninsular Malaysia. Universiti Pertanian Malaysia Press, Kuala.umpur. 284 p. New Straits Times Fishing for business. N.S.T. Times Two. 21st Jan Ong, KS Aquaculture development in Malaysia in the 80's. Risalah Perilcanan No. 18. Dept. of Fisheries, Malaysia. Scott, J.S An introduction to sea fishes of Malaya. Government Printer (Fudge), Kuala Lumpur: xii Shariff, M Occurrence and treatment of ectoparasitic disease of aquarium fishes in Malaysia. Malayan Veterinary Journal 7: Shariff, M Occurrence of Chilodonella hexasticha (Klemik 1909) (Protozoa, Ciliata) on bighead carp Aristichihys nobi1s (Richardson) in Malaysia. Tropical Biomedicine I: Shariff, M. and C. Somerville Identification and distribution of Lernaea spp. in Peninsular Malaysia, p In J.L. Maclean, L.B. Dizon and L.V. Hosillos (eds.) The First Asian Fisheries Forum. Asian Fisheries Society, Manila, Phillipines. Soong, M.K Fishes of the Malayan paddy fields: 1. Sepat Siam. Malayan National Journal 3(2): Soong, M.K., A note on the pond culture of Puntiiesjavanicus (Bikr) in the Federation of Malaya. Proceedings IPFC 10(2;: Tan, C.E., B.J. Chong, H.K. Sier and T. Moulton A report on paddy and paddy field fish production in Krian District, Perak. Ministry of Agriculture & Fisheries Bulletin No. 128: 58 p. Tweedie, M.W.F Notes on Malayan freshwater fishes. Bulletin Raffles Museum 24: Welcornme, R.L Register of international transfers of inland fish species. FAQ Fisheries Technical Paper. (213): 120. Welcornme, R.L International measures for the control of introductions of aquatic organisms. Fisheries 11(2): 4-9.

94 The Introduction of Exotic Aquatic Species in the Philippines ROGELIO 0. JULIANO Univesizy of the Philippines in the Visayas Iloilo City, Philippines RAFAEL GUERRERO Ill Philippine Councilfor Aquatic and Marine Research and Development College, Laguna, Philippines INOCENCIO RONQUILLO Bureau of Fisheries and Aquatic Resources Quezon Blvd., Quezon City, Philippines Juliano, R.O., R. Guerrero ifi and I. Ronquillo The introduction of exotic aquatic species in the Philippines, p In S.S. Dc Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Publ. 3, 154 p. Asian Fisheries Society, Manila, Philippines. Philippines is an archipelago with a number of islands, each with its characteristic flora and fauna. Aquatic organisms have been introduced into the Philippines mainly for increasing production, as a protein source for the poor. Not all the introductions, however, have been successful. Some of the introductions have had detrimental effects on the endemic fish fauna, particularly the cyprinid flock of Lake Lanao. Recommendations for possible future introductions are suggested. Aquatic species found in inland waters particulary in outlying lakes and rivers may remain isolated for a long period of time without interference from man. In an archipelago like the Philippines with numerous islands, the isolation of such aquatic species and even land species still occurs. Over the years, through man's interference, such isolation has been broken through introduction of new species, which may completely dominate and wipe out the endemic and/or indigenous aquatic species. Lake Lanao in the island of Mindanao has many endemic cyprinids and their taxonomy and genetics had aroused much interests. The stocking program of the Government with the view to increasing production from lakes accidentally introduced a freshwater, carnivorous goby (Glossogobius giuris) into Lake Lanao. The goby is now a predominant species in the lake and has been responsible for depleting the cyprinid populations in the lake. Herre (1924) states, "In the Philippines, Cyprinidae are apparently confined to Mindanao, Basilan and Tawi-Tawi, and to the Palawan biological province, where they occur on Balabac, Palawan, Busuanga and Mindoro". Herre continues to say that the Cyprinidae of Mindanao entered from Borneo over a Sulu Land bridge. The cyprinids of lake Lanao have been isolated a 83

95 84 long time ago as shown by the fact that three genera and all of the species of cyprinids living there are endemic to the Lake. Introduction of exotic species into the different islands from other islands of the country or from other countries, requires serious study and careful consideration, particulary on adverse effects such introductions may produce on endemic and indigenous species. Government should adopt strict policies and guidelines to regulate introduction of exotic species. Almost all aquatic introductions into the country were meant to benefit the country, through aquaculture, capture fisheries, or for biological control purposes. However, the benefits that were derived did not really outweigh the adverse effects that came about as a result of some of the introductions. There were introductions of exotic aquatic species that were done by individua:ls without the knowledge of the Government. Even in pet shops in Manila, exotic species of fishes can be found which were brought into the country without government clearence. Certain species that are or were available for purchase from pet shops or dubious sources are species of Serrasalmus (pirranha), Pangasius and other catfishes. Such exotic species fortunately are not yet found in the wild and are evidently confined as pets for the time being. No action on the part of the Government has been observed to regulate such introduction. Recorded Exotic Fish Species in the Philippines The first recorded introduction of an exotic fish species to the Philippines was in 1907 when Mr. Alvin Seale was authorized by the Philippine Insular Government to import from California, fingerlings of largemouth bass, Micropterus salmoides. Introductions as a food fish and for sport, were made in ponds and lakes specially in higher altitudes in the Mountain Province (Baguio City) and Caliraya Lake in Laguna Province. This species does very well in higher altitudes where temperatures are the same as subtropical zones. Luckily, this fish did not thrive in lowlands where many lakes abound. It is only in Lake Caliraya that M. salmoides is known to be doing well, at 700 meters above sea level, and in 1985 another related species, Micropterus salmoides floridanus was received as a gift from California and stocked in Caliraya Lake (a reservoir). Bass fishing tournaments are held in this reservoir regularly. Subsequently, other introductions of aquatic species, mostly fish, were made with reasons that varied from providing more food fish for the country in lakes and rivers, for aquaculture purposes, for biological control of undesirable species such as mosquitoes and weeds, for sport fishing and others. Some of the introductions became nightmares for aquatic-based industries like the brackishwater farming industry; for e.g., introduction of Mollienesia latipinna (molly) for the purpose of controlling malarial mosquitoes. The mosquito fish, however, became a pest in brackishwater ponds. Other fish species introduced for control of mosquitoes were Gambusia affinis, Poecilia reticulata and Fundulus heteroclitus. The introduction of Tilapia mossambica (Mossambique tilapia) was a real nightmare for brackishwater farming, competing for food in the farm with Chanos chanos (milkfish). The Mossambique tilapia is now an established species in brackishwater farms in the entire country. The Philippine freshwater catfish, Clarias macrocep ha/us, became completely dominated by an exotic species, C/arias batrachus, imported from Thailand during the craze for catfish farming patterned after the success in Thailand. Clarias batrachus now dominates natural populations in lakes and rivers and the indigenous C. macrocephalus can hardly be found in the markets nowadays. C. macrocephius has better qualities as a food fish compared to C. batrachus.

96 Other introductions did not make much impact and these were not regarded by Filipinos as significant in terms of benefits and adverse effects. The introduction of Ictalurus catus, Ictalurus punctatus, Lepomis macrochirus, Misgurnus auguillicaudatus (bach), Puntius javanicus, Osphronemus gorami and others for a time created some interest but did not affect the environment as much as other introductions. The Ictalurus species did not survive in natural conditions in the Philippines and no natural population is known. Lepomis (bluegill) is believed to have survived in some reservoirs at high elevations and serves as forage fish for the M. salmoides. The Japanese bach (Mis gurnus anguillicaudatus) established itself in some waters in Trinidad Valley and rice terraces in Bontoc Province but has not had any negative effect. Puntius (tawes) and Osphronemus (giant gouramy) for a while became known as good aquaculture species but eventually lost out to other more favorable and acceptable species for freshwater famiing. The introductions of other cyprinid species in the Philippines and tilapia species have made more impact economically for the Philippines than the other exotics. All available commercial species of cyprinids in the country except in Lake Lanao are considered exotic species. Even the presence of the varieties of goldfishes and carps for aquaria are exotic species but records of their introduction do not exist. The aquarium fish industry benefits from these species. Cyprinus carpio (common carp), and Chinese and Indian carps (such as grass carp, silver carp, bighead carp, rohu, catla, mud carp, and mrigal) have been introduced into the Philippines. Several Chinese carps and rohu have become a part of natural populations of lakes and reservoirs and contribute to natural fish production. Many have become important cultured species such as the common carp, bighead, silver carp and grass carp particularly for pen culture in Laguna de Bay and freshwater ponds. Since they can be artificially bred, their domestication has helped the freshwater aquaculture industry. Oreochromis niloticus is now an important freshwater fish cultured in pens, cages and ponds. Among the exotic anabantids in the Philippines, Trichogater pectoralis and T. trichopterus have thrived well in lakes. They have been accepted by consumers inland where marine species hardly influence their preference for fish. 85 Other Exotic Aquatic Species in the Philippines Nonpiscine aquatic introductions are not weil recorded but mention will be made of them. In the recent past Ampularia gigas (golden miracle snail) generated interest as a cultured species that can thrive in tanks and even small containers when fed with vegetable materials. They breed in the culture containers and grow at a fast rate. Its success was temporary and many now consider it as a pest in rice paddies because they feed on young rice plants. Cristaria plicata, a big freshwater clam, all of a sudden appeared as a natural population in the 1970s in Laguna de Bay. It is claimed that the clam may have been accidentally introduced into the lake as glochidia in the gills of imported Chinese carps stocked in the lake. Crassostrea gigas is believed to have been introduced in Pangasinan by Mr. Ablan from Japan. Its culture was studied but without much success. Penaeid shrimps were also introduced into the Philippines (Iloilo) for aquaculture. It is claimed that two species, Penaeus stylirostris and P. vanamei from Latin America when introduced to the Philippines, may also have introduced diseases to local penaeid species. Table 1 summarizes the exotic aquatic species in the Philippines. The data may not be complete as some of the old records are hard to trace.

97 86 Discussion and Recommendations Experiences in the past have revealed that many aquatic species have been introduced into the Philippines from other countries either through government efforts or through efforts of private individuals, with or without the concurrence of the Government. Such introductions of exotic aquatic species, mostly fishes and invertebrates, proved beneficial to food production efforts of the Government but in some instances resulted in adverse environmental impacts; the introduced species becoming pests to other crops, new diseases being introduced, with exotic species, and indigenous species being completely dominated or displaced. It also seems apparent from the past that the Government has failed to control and study the negative effects that such introductions would entail, with accidental releases in natural waters taking place. Fortunately, epidemics caused by parasites and diseases accompanying introductions have not yet taken place Ḋespite many undesirable turns of events from exotic aquatic introductions, adoption of strict government policies on importation of exotic species has been paid only lip service during meetings and workshops. In view of the above, it is recommended that the Government adopts and implements policies, or even enact laws, that will strictly prevent the ill effects of introduction of exotic species into the country. Priority consideration should be given to indigenous and endemic species for utilization to increase fish production in natural waters and in aquaculture before considering exotic species for such purposes. It is proposed that the following be considered as guidelines in the importation of exotic aquatic species into the country: A thorough study of utilizing indigenous/endemic species be made Ibr whatever purposes/objectives have been planned before any decision to introduce an exotic species is made. If and when a decision to import an exotic species is made, a thorough study of its biology, results of introduction in other countries, and the effects of such introduction on local species and the environment should be undertaken before actual importation is made. ImportatiOn of the exotic species from a very reliable source, preferably from a research organization where diseases have been controlled and the genetic constitution of the species is guaranteed, should be ensured. On arrival of the imported species, strict quarantine measures should be undertaken. It is desirable that no organisms are released into natural waters or to private individuals until the F1 generation or F2 generation has been produced, and which has been given a clean bill of health by pathologists. Introduction of exotic species in natural waters should be properly monitored and done gradually in one or two areas before any introductions into major natural waters are made.

98 87 Relevant Literature Gracia, D.M Some notes on the stocking of Cyprinu.s carpia and genguno buna in Pampanga river system. BFAR, Quezon City, 4 p. (handout). Herre, A.W.C.T Distribution of the tme freshwater fishes in the Philippines. I. The Philippine Cyprinidae. Philippine Journal of Science 24(3): Herre, A.W.C.T An American cyprinidont in Philippine salt ponds. Philippine Journal of Science 38(1): Herre, A.W.C.T Checklist of Philippine Fishes, p Fishes 1931 Philippine Expedition,p. 22, Rabana, H.R. and L.V. flosillos Control of less describe exotic species of fish competing with or harmful to desirable indigenous species in inland waters in the Philippines. Philippine Journal of Fisheries 6(1): Ronquillo, l.a The tilapia and its introduction of new species into freshwater areas. Proc. MAB Inter-Agency Meeting. Seale, A The successful transference of blackbass to the Philippine Islands, with notes on the transporting of live fish long distances. Philippine Journal of Science 5(3): Seale, A The mosquito fish, Gambusia affinis (Baird and Girard), in the Philippine Islands. Philippine Journal of Science 7 (3): Velasquez, C Digenetic trematodes of Phiippme fishes. Nat. Res. Council Phil., University of the Philippines Press, 140 p. Villaluz, D.K Fish farming in the Philippines. Bookman, Inc., Manila, 336 p.

99 Table 1. Exotic aquatic species introduced into the Philippines. Taxonomic status Introduced From Year Habitat Pisces Family CYPRNTDAE Cyprinus carpio Hongkong 1915 Lakes, reservoirs (common carp) China, canton Formosa Formosa rivers,ricefields ponds (Sinjonja variety) Bogor,Indonesia 1956 (Punten variety) -do (Red variety) -do (Majalaya Strain) Indonesia 1988 C:enopharyngcidon India 1967 Rivers idella (grass carp) Arislichthys nobilis (bighead carp) Hypophthalinichzhys moltrix (silver carp) Taiwan 1968 Lakes, ponds Taiwan 1968 Lakes, ponds Labeo rohila (rohu) India 1967 Lakes, reservoirs Coda coda (catla) India 1967 Carassius carassius (cnlcian carp) Japan 1964 Ponds Cirrhinus,nolitorella (mud carp) or Cirrhinus rnrigala India 1967 Puntiusjavanicus Bogor, Indonesia 1956 Lakes, rivers Bleeker (Tawes) Osteochilus hasselti -do Cuvier & Valenciennes (nilem) Family CICHLIDAE Oreochromis mossambicus Thailand 1950 Lakes reservoirs (Peters (tilapia) rivers, ricefield Mozambique tilapia ponds, swamps highlands 0. niloticu.s Thailand 1970,1972 -do- (Nile tilapia) Israel aureus Alabama, USA 1977 (Blue mouthbrooder) Present Status Diseases/Parasites Commercial fishesy Aeramonas salmonicida, naturally breeding A. hydrophila population, mass seed Pseudomonasfluorescens production, cultured Edwardsiella larda Dacty1ogyrus Artificially spawned -do- -do- -do- Naturally breeding Monogenetic trematodes population, cultured Dactylogyrus Gyrodactylus Parasitic, protozoan Trichodina Naturally breeding population Ichihyophihirius Oodonium Transversotrema larvei skin (under scales) Commercial fishery -donts,i,,os'," Lpistyies, Trichodina Continued

100 Table 1. Continued Taxoornic status Introduced Habitat Present Status From Year Tilapia zulu Israel 1977(?) Reservoirs, lakes (Zill's tilapia) Family OSPHRONEMIDAE Trichogasser pectoral is Hene (snake-skin plasalid) Bangkok, Thailand 1938 Lakes, ricefields ponds Naturally breeding population, cultured T. trichopserus -do Lakes, rivers Naturally breding population Herre (Three spot plasalid) T.!eerj Bleeker (pearl plasalid) -do do- ricefields, ponds swamps Osphronemus gouramy Java 1927 Lakes, ricefields -do- Lacepede (giant gouramy) Indonesia ponds Helostoma temmincki Bangkok, Thailand Cuvier & Valenciennes (Kissing gourami) Bogor, Indonesia 7'52 Bogor, Indonesia 2' , Catfishes Ictalurus calus California, USA 10'35 (Linnaeus) catfish Clarias batrachus Thailand 1972 Ponds (Thai catfish) Ponds and other Natural waters Ictalurus punctatus California, USA 1974 Reservoirs Localized distribution (Channel catfish) Pangasiu.s sutchi Thailand 1978 Ponds, reservoirs (Pla swai) Clarias lazera Thajwan 1985 Ponds Experimented (African catfish) Family CENTRARCHIDAE Micropterus sal,noides California, USA 1970 Reservoirs, lakes Localized distribution Le Suer (Black bass) M. salrnoidesfloridatzus 1985 Reservoirs (Florida bass) Lepomis macrochirus California, USA 1950 Swamps, highland Localized distribution Rafferty (blue gills) L. cyanellus -do do- Diseases/Parasites Opegaster,nininia (intestine) Clinostomoides opehicephal Clinosiomoides brieni encysted in gills and opercular cavity Continued

101 Table 1. Continued Taxonomic status Introduced Habitat Present Status From Year Family COB1TIDAE Mirgurniis aguil1icadatu (Canton (Loach) or whetherfish) Family POECIILIDAE Gambusia affinis Baird and Girard (Top minnow or Japan Before 1937 Honolulu, Hawaii Highland rivers, ricefields Brackishwater Ponds mosquitofish) Mollienesia lalipinna Honolulu 1914 Brackishwater Le sueur (top minnow or mosquitofish) Fundulus heteroclilus (mosquitofish) Poecilia (Mollienesia) reticul ala (mosquito fish) Molluscs Ampularia gigas Golden miracle snail (kuhol) Crislaria plicata Accidential introduction with Asiatic caips (?) Hawaii ponds -do do Florida, USA 1980 River, ponds lakes, imgation Lake (L de Bay) Penaeid Shrimps Penaeus stylirostris 1980(?) Penaeus vanamei 1980 (?) Naturally breeding Lo'alized distribution naturally breeding population Commercial fisheiy, natural breeding, 1s, ncefields, fishpens/cages Diseases/Parasites

102 Introduction of Exotic Aquatic Species in Singapore L.M. CHOU T.J. LAM Department of Zoology National University of Singapore Kent Ridge, Singapore 0511 Chou, L.M. and T.J. Lam Introduction of exotic aquatic species in Singapore, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, l54p. Asian Fisheries Society, Manila, Philippines. Urbanization has changed much of Singapore's landscape and affected its natural fauna. Exotic species have been introduced for economic or commercial purposes. Two such species that have become firmly established in Singapore's inland waterways are the guppy (Poecilia reticulata) and the tilapia (Oreochromis mossambicus). The country lacks extensive natural inland water bodies as well as indigenous inland fisheries, and the introduction of exotic species is not likely to cause much concern. No serious study on the ecological impact of introduced species has been made. The natural landscape of Singapore has changed drastically since the island's founding in During the early days, large tracts of forests were cleared by industrious cultivators and replaced by plantations of pepper, coffee, rubber, sugar-cane, gambier and other crops. As urbanization continued, remaining forests as well as disused and existing agricultural land were systematically cleared at increasing pace for commerce, industry and housing. Today, 28.6 km2 of nature reserves and secondary forests surrounding the reservoir catchment areas remain while land for agrotechnological use such as for agriculture and aquaculture, has been designated in ten parks intended for farming at high technology level. These parks occupy about 180 hectares, and the area is expected to increase to 2000 hectares over the next decade (Yap 1987). The drastic changes in the environment affected the natural fauna of the island. Some species of plants and animals were reduced or even exterminated. At the same time these changes favoured the proliferation of other species that were introduced accidentally or intentionally. Some of the exotic species were brought in and raised for their ornamental, economic or commercial potential. This included indigenous ones which would otherwise have been exterminated had they not been introduced for the reasons mentioned. This paper will deal only with the aquatic animal species. No studies have been made on the ecological significance and implications of introduced species. Aspects such as parasite and other disease introduction and transmission, their effect on the environment, and the competition of introduced species with indigenous ones have not been given attention, but warrant systematic investigation. In cases where the ecological impact of an introduced species can be predicted legislative and other measures have been taken by the government to stop their entry. An example of this is the ban on the import of piranhas under the 91

103 92 Fisheries (Piranhas) Rules 1971, enacted as a supplement to the Fisheries Act, It is now illegal to rear or release the fish into natural waterways. Species Introduced for Biological Control The only species recorded as having been introduced for biological control is the guppy, Poecilia reticulata. This species was introduced in 1937 for mosquito control (Herre 1940) and has since become well established in polluted waters having free ammonia concenirations of a few hundred parts per million (Johnson 1973). Freshwater Species Trionyx sinensis (Chinese soft-shell terrapin) Species Introduced for Culture In the early 1970's, some hatchlings were brought in from Taiwan by an enterprising farmer to test the viability of the species in Singapore. It adapted well to the tropical conditions. Because of its higher fecundity and faster growth rate under these conditions, it is now cultured in preference to the slower-growing native species, T. cartilagineus. Endemic to China, T. sinensis has been successfully cultured for over 60 years in Japan and 100 years in Taiwan. The warm climate in Singapore allows a higher production rate than in the temperate region, but its culture is land intensive. Therefore, although Chinese soft-shell terrapin farming is lucrative in Singapore, it is limited to two farms. There have been cases of escape of these terrapins into inland water systems. Although the implications have not been considered, there is every likelihood of some ecological disturbance because of their ability to reproduce faster in the tropics, and their voraciousness (live fish forming the main part of their diet), especially if they find their way into sheltered waters where fish are stocked, such as reservoirs. Crocodilus porosus (estuarine crocodile) and Tomistoma schiegeli (Malayan gavial) Sharma (1973) reported that it was unlikely for any large individuals of Crocodylusporosus to be found in the wild although they were a major hazard in coastal waters and mangroves in the earlier days. The presence of the Malayan gavial in Singapore waters although rumoured, has never been substantiated. Both species have together with other crocodilian species, been reintroduced for farming. Their escape always causes great concern because of the apparent danger to man and occasional escapes have occurred.

104 93 Oreochromis mossambicus (common tilapia) The very hardy tilapia was introduced by the Japanese Army during their occupation of Singapore from (Harrison and Tham 1973). The constant warm climate enabled the species to breed rapidly all year round. It was not well received as a foodfish and has since become free-roaming, with feral populations inhabiting freshwater and low-salinity habitats. Most of the populations now consist of stunted individuals (Johnson 1973). The impact of this fish on the environment is yet to be fully assessed but it appears to have dominated reservoirs and man-made lakes. Khoo et al. (1977) have estimated the tilapia population in the Seletar Reservoir to consist of 10.2 million juveniles and 10.3 million adults in 1975/76. Mass mortality occurred in 1972 (about 300,000 died between October and December) due apparently to sudden oxygen decline as a result of mixing of oxygen-stratified water layers caused by climatic changes. Carps Common carp, Cyprinus carpio, Chinese carps, comprising Ctenopharyngodon idellus (grass carp), Aristichthys nobilis (bighead carp), Hypophthalmichthys molitrix (silver carp); and Cirrhina molitorella (mud carp). Chinese carps were introduced by the Chinese immigrants during the early history of Singapore. Their culture in ponds was on a restricted scale, with fry imported from China and timed such that harvests coincided with Chinese festivals. After the Second World War, the dramatic increase in cost of marine fish made the cheaper carps a popular food item. Their culture was subsequently stepped up to produce the fish the year round (Tham 1975). Gradually, increasing land demand led to a decline in carp culture as ponds were reclaimed. Carp culture is now confined to less than 100 hectares of ponds with prospects of further decline and to the reservoirs such as Seletar Reservoir where bighead carps are reared in floating cages without supplementary feeding to reduce algal and nutrient load as the fish feed on plankton. Marine species Finfish None of the finfish species imported for culture can be considered as exotic as they can also be found in local waters. These are mainly the grouper, Epinephelus salmoides, and seabass, Lates calcarifer (Anon 1986). The impact of culture of large numbers of these fish in 65 floating fish farms in coastal waters with the attending possibility of escape and spontaneous breeding, on the environment is not known. As local collection from the wild and hatchery production are still insufficient to support the industry, seabass and grouper fingerlings have to be imported from mainly Thailand and the Philippines. As with all imported species, the potential danger from diseases is present and the possibility of introduction of new strains of pathogens exists. However, ectoparasites found on imported fingerlings are probably similar to those found locally and it is likely that these parasites were absent prior to fish importation. Other species cultured on a smaller scale because of the lack of seed supply include snappers (Lutjanus johni, L. argentimaculatus), coral trout (local red grouper, Plectropomus maculatus), yellowfish jack

105 94 (Caranx ignobilis) golden trevally (C. speciosus), and siganids (Siganus canaliculatus, S. guttatus). Other species not commonly found or not existing locally but could be considered for culture are other groupers such as the tiger grouper (E. microdon) imported from Indonesia and cultured with some success, and the HongKong red grouper (E. akara). The red tilapia hybrid (Oreochromis niloticus hybrid) has been introduced for marine culture by some farmers using originally freshwater stocks acclimated to sea water conditions. Marine stocks may become available in the future. The fish has also been stocked in limited numbers (8000 fry) into the Singapore River, together with 560,000 banana prawns (Penaeus merguiensis) and 34,000 sea bass (L. calcarifer) (L. Cheong personal communication). The impact of this stocking is still uncertain. Shellfish The healthy market for prawns and limited land availability has encouraged farmers to culture prawns (P. merguiensis) semi-intensively in brackishwater ponds insteadi of trapping them by the traditional method. The Kuruma prawn (P. japonicus) has been imported by a Japanese company and initial trials in lined ponds and at intensive stocking have been sufficiently encouraging for commercial farming to be initiated. Other penaeid species such as P. monodon (tiger prawn), and foreign ones such as P. stylirostris (blue prawn), P. vannamei, P. esculentus (brown tiger prawn), P. orientalis (Oriental prawn) and P. indicus (Indian prawn) may be considered, if environmentally and economically suitable for culture. The tiger prawn, although indigeneous is not easily available, and culture is restricted because of the lack of suitable salinity conditions. The spiny lobster most popularly cultured because of its availability is Panilurus polyphagus, although other species from neighbouring countries could be imported if available in large enough numbers for culture. It is unlikely that their escape from the farni; will allow them to establish significantly in some of the marine habitats like coral reefs as they are much sought after by fishermen, collectors and enthusiasts. The indigenous mangrove crab (Scylla serrata), originally from mangrove areas, and previously cultured on small scale in narrow earth furrows in the vicinity of traditional prawn ponds, are now imported for culture in wire cages at some commercial floating fish farms due to the rapid reduction of mangrove forests. They are imported from Sri Lanka and Indonesia and kept in the cages for around two weeks to fatten, and then sold locally. It is unlikely that there is sufficient wild-caught stock for this purpose, and the reduction of mangrove areas in Singapore to less than 250 hectares will have contributed to the scarcity of the mangrove crab. Species Introduced for Ornamental Value Johnson (1964, 1973) reported 5 species of freshwater fishes which have been introduced. Puntius semifasciolatus was accidentally introduced from China and being tole:rant, is well established in the catchment area. Small populations of the true fighting fish, Betta splendens, have established in Jurong Lake and water bodies in the Sembawang area. Also well-established in the wild is the introduced Trichogaster pectoralis, while the mollies, Poecilia sp henops and Poecilia affinis, have established permanently in low salinity waters.

106 Many other species of ornamental fish are imported and/or farmed in Singapore (Table 1). Accidental escape or even deliberate release of these species into natural waterways is likely but the impact, if any, is not noticeable. They are probably unable to compete with the hardier feral guppy and tilapia. 95 Discussion Singapore does not have extensive natural inland water bodies nor does it have an indigenous inland fisheries. There is also at present hardly any unique inland aquatic fauna to protect either. As such, introduction of exotic species does not cause much concern and there has not been any serious study of the impact of species introduced for farming or other purposes. However, two introduced species appear to have firmly established in Singapore's inland waterways, and these are the guppy (P. reticuluta) and the tilapia (0. mossambicus). Acknowledgement We would like to thank Mr. Robert Lee, Mr. Leslie Cheong and Mrs. Audrey Yuen of the Primary Production Department of Singapore for providing us with some of the information in this paper. References Anon Manual on floating netcage fish fanning in Singapore's coastal waters. Fisheries Handbook No. 1, Pnmasy Production Department, Minisuy of National Development, Republic of Singapore. Harrison, IL. and A.K. Tham The exploitation of animals, p In Chuang, S.H. (Cd.) Animal life and nature in Singapore. Singapore University Press, Singapore. Herre, A.W.C.T Additions to the fish fauna of Malay and notes on rare or little known Malayan and Bomean fishes. Bulletin Raffles Museum Singapore 16: Johnson, D.S An introduction to the natural history of Singapore. Rayirath (Raybooks) Publications, Singapore, p Johnson, D.S Freshwater life, p In Chuang, S.H. (ed.) Animal life and nature in Singapore. Singapore University Press, Singapore. Khoo, H.W., S.L. Yang and C.J. Cioh A preliminary limnological study of Seletar Reservoir. Journal of Singapore National Academy of Science 6: Sharma, R.E Noxious and toxic animals, p In Chuang, S.H. (ed,) Animal life and nature in Singapore. Singapore University Press, Singapore. Tham, A.K Fish and prawn ponds, p In Chuang, S.H. (ed.) Animal life and nature in Singapore. Singapore University Press, Singapore. Yap, H.B More farmland in agrotech parks for tender. Primary Production Bulletin No. 274, May 1987: 1.

107 96 Table 1. Main species of aquarium fish imported into Singapore (infonnation kindly provided by the Primaiy Production Department of Singapore). Freshwater Fish Angel Barb Guppy Swordtail Platy Gouramy Plerophyllus allus Pterophyllus scalare Acrossocheilus bantamensis Barbodes birnaculalus Barbodes everetti Barbodesfasciatus Barbodes hassecti Barbodes hexazona Barbodes lateristriga Barbodes partipenlazona Barbodes schwanenfeldi Barbus arulius Barbus binotatus Barbus cumingi Barbusfilamenlosus Barbus holotaenia Capoeta arulius Capoeta chola Capoeta oligolepis Capoeta semifasciolatus Capoeta let razona Capoeta lilteya Esomus dannica Osteochilus hasselti Osteochilus vitattus Puntius asoka Puntius conchonius Puntius curningi Puntiusfilarnentosus Puntius gonionotus Puntius lineal us Puntius nigrofasciatus Puntius sachsi Puntius schwanenfeldi Puntius semifasciolatus Punlius stigma Tanichthys albonubes Poecilia reticulata Xiphophorus helleri Xiphophorus maculatus Xiphohorus variatus Belontia signata Colisa chuna Colisafasciata Colisa labiosa Colisa lalia Helostoma rudolfi Macropodus opercularis Osphronemus goramy Sphaerichthys osphromenoides Trichogaster leeri Trichogaster microlepis Trichogaster pecloralis Trichogaster Irichopterus Trichogaster sp. Trichopsis vitt at us Freshwater Fish Cichlid Molly Goldfish Tetra Acarichthys heckelii Aequidens curviceps Aequidens maroni Aequidens puicher Aequidens let ramerus Apistogramma ramirezi Apistogramma sp. Astronotus ocellalus Aulonocaro.sp. Chromidotilapia sp. Cichiasoma cynogula/tus Cichlasomafestivwn Cichiasoma meeki Cichiasoma nigrofascictus Cichiasoma severum Chiclasoma sp. Geophagus sp. Haplochromis sp. Hemichromis bimacuiatu.s Hemichromis sp. fodotropheus sprengerae Jordane/lafloridae Labeotropheus sp. La,nprologus sp. Melanochromis sp. Nannochromis nudiceps Nannochronsis sp. Pelmatuchromis kribensis Pseudotropheus aura rus Pseudotropheus zebra Pseudolropheus sp. Steal ocranus casuarius Symphysodon aequifasciata Tilapia aurea Tilapia sp. Uaru amphiacanthoides Poecilia latipinna Poecilia sphenops Poecilia velifera Carassius auratus aielus Anoptichthysjordani Aphyocharax rubripinn is Astyanaxfasciatus mexicanus Astyanax mexicanus Cheirodon axelrodi Gymnocorym bus terneizi Hasemania nanas Hemigrammus caudoeitiatus Hemigranmus erythrmonus Hemigrammus gracilis Hemigrammus ocellifer Hemigram,nus pulcher Hemigrammus rhodostomus Hyphessobrycon bento:?i Hyphessobrycon bfasciatus Hyphessobryconflamsreus Hyphessobrycon herhetaxelrodi Hyphessobrycon pulchripinnis Hyphessobrycon rosac'us Hyphessobrycon rubro.stigma Hyphessobrycon schol2ei Hyphessobrycon serpa? Continued

108 97 Table 1. Continued Freshwater Fish Leach Danio Discus Fighting Fish Shark Algae Eater Harlequin Megalamphodus megalopteriss Metynnis maculatus Metynnis roosevelti Micratestes interrupt us Moenkhausia oligolepis Nematobrycon amphiloxus Paracheirodon innesi Prionobramafihigera Prisiella riddlei Thayeria obliqua Acanthophihalmus myersi Acanthophthalmus semicinctiss Acarahopsis choirorhynchus Botia horae Botia hyinenophysa Botia macracantha Botia modesta Botia sidihimunki Cobitis iaenia Noemacheilus botia Noemacheilusfasciatus Noemacheilus kuiperi Brachydanio albolineatus Brachydaniofrazkei Brachydanio malabaricus Brachydanio rerio Danio malabaricus Symphysodon aequfasciaia aequjfasci Symphysodon aequzj'asciata axeirodi Symphysodon aequifasciata haraldi Symphysodon discus Betta bellica Betta brederi Betta splendens Balantiocheilus snelanopterus Labeo bicolor Labeo erythrunus Labeo variegatus Lepiobarbus hoeveni Morulius chrysophekadion Gyrinocheilu.s aymonieri Rasbora dorsiocellata Rasbora einthoveni Rasbora elegans Rasbora heteromorpha Rasbora kalochrorna Rasbora macuiala Rasbora pauciperforala Rasbora sieineri Rasbora taeniata Rasbora trilineala Rasbora vaterfloris Freshwater Fish Carp Scat Eel Scissor Tail Catfish Marine Fish Gown Butterfly Damsel Tang Peacock Lion Trigger Wrasse Surgeon Aristichthys nobilis Carassius gibelio Cienopharyngodon idella Cyprinus carpio Hypophthalmichthys molitrix Scat ophagus argus Electrophorus eleciricus Fluta alba Macrognathus aculeatus Mastacembelus,naculatus Mastacembelus sp. Rasbora caudimaculata Brochis coeruleus Chacasp. Corydoras aeneus Corydoras hasiatus Corydorasju!ii Corydoras melanistius Corydoras melanislius brevirostris Corydoras myersi Corydoras naitereri Corydoras paleatus Corydoras xinguensis Hypostomus plecostomus Kryptopterus bicirrhis Kryptopierus macrocephalus Leiocassis siamensis Leiocassis sp. Malapterurus eleciricus Microglanis arahybae Mystus tengera Ompok hi maculat us Pangasius sanitwongsei Pangasius sutchi Synodontis nigriventris Synodontis notatus Synodontis sp. Mono Mohodactylus argenteus Monodactylus sebae Bumble Bee Brachygobius sp.

109

110 Status of Introduced Species in Sri Lanka SENA S. DE SILVA Departments of Fisheries Biology and Zoology University of Ruhuna Matara, Sri Lanka De Silva, S.S Status of introduced species in Sri Lanka, p. 99. In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. Much has been written on the introduced species and their impact on the fisheries of Sri Lanka in the last two decades. As such no attempt is made here to deal with this subject, again, as there is very little available in the way of fresh information. The readers are therefore, directed to the following references. De Silva, S.S Status of the introduced cichlid Sarotherodon mossambicu.s (Peters) in the reservoir fishery of Sri Lanka: a management strategy and ecological implications. Aquaculture and Fisheries Management 16: De Silva, S.S Impact of exotics on the inland fishery resources of Sri Lanka. Archives Hydrobiologie Beiheft, Ergebnisse der Limnologie 28: Fernando, C.H The role of introduced fish in fish production in Ceylon's freshwater, p In E. Duffey and A.S. Watts (ed.) The Scientific Management of Animal and Plant Communities for Conservation. Blackwell Scientific Publications, Oxford, England. Fernando, C.FI. and H.H.I. Indrasena The freshwater fisheries of Ceylon. Bulletin Fisheries Research Station, Ceylon 20:

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112 Exotic Aquatic Species in Taiwan I-CHIU LIAO Taiwan Fisheries Research Institute 199 Hou-Ih Rd., Keelung Taiwan HSI-CHIANG LIU Institute of Oceanography College of Science National Taiwan University Taipei, Taiwan I-Chiu Liao and Hsi-Chiang Liu Exotic aquatic species in Taiwan, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec, Pubi. 3, 154 p. Asian Fisheries Society, Manila, Philippines. There are 38 aquatic species known to have been introduced to Taiwan. The earliest introductions were probably those of the Cyprinidae family, although documentation to this effect is lacking. Other more recently introduced species, like the tilapias, are relatively well documented. Some of the introduced species have been successfully cultured. The introductions are discussed and, where information is available, a more detailed history, including problems, if any, is presented. The problem of the lack of consolidated information is also discussed. Distances in the world today have shrunk considerably due to the improvements in transportation and communication technology. Under such conditions, many species of aquatic organisms have been transferred to regions of the world where they are not naturally occurring. The term "exotic" species refers to any species introduced by man from a foreign land (McCann 1984). This should not be confused with "transplanted" species - native species moved by man into an ecosystem outside their native range, but still within their country of origin, and with "nonnative" species - any species introduced by man into an ecosystem outside its original native range, including both exotic and transplanted (McCann 1984). Of special interest in this report are exotic aquatic species known to have been introduced to Taiwan at different times. However, it would be useful to mention at this point, the particular case of two species in Taiwan, which would be hard to categorize in the context of the above definitions. One is Penaeus monodon or grass prawn. This species is native to Taiwan, but since insufficient spawners were available locally, about a decade ago, Taiwan began importing great numbers of adult P. monodon from neighboring countries, like the Philippines and Malaysia, and induced these adults to spawn. Most of the P. monodon that have been cultured here were spawned from adults obtained from abroad. The other is Plecoglossus altivelis, commonly known as "sweet fish" or "ayu". It is an indigenous species in Taiwan, but became extinct in the 60's. It only began repopulating local waters when Japan introduced it several years hence. Perhaps in the future, more accurate and exact definitions of such terms should be formulated and internationally agreed upon - to cover special cases such as that of P. monodon and P. altivelis. 101

113 102 Table 1 lists various species known to have been introduced to Taiwan at different times. An assessment of the status of these species, based on five criteria, is presented in Table A.II.8, in the Appendices to this volume. This assessment table (as well as Table 1) was limited to major food fishes only, as this was the focus of the workshop in which this report was presented. However, a list of ornamental fishes introduced into the country is given in Annex I. Status of Introduced Species Many of the exotic aquatic species introduced into Taiwan, such as the tilapias, have been greatly beneficial. A few, like the giant African snail, Achatina fulica, and the apple snail, Ampullarius insularu,n, have caused serious damage to the local environment. The more information is documented on introductions of exotic species, the easier it will be to monitor their consequences and the government will be able to manage the country's fisheries resources and aquaculture industry better. It is regrettable that the history of introductions of exotic aquatic species into Taiwan has not been well recorded. This report is the result of an initial effort to collect and compile whatever information is available from various, scattered sources. It is far from complete. Hopefully, other colleagues can gradually build upon the modest foundation that it has attempted to lay down. Gambusia affinis Finfish Gambusia affinis or topminow was introduced from North America to Taiwan in the early 20's. It is generally accepted that this species was introduced to control malaria. It spread all over Taiwan as a wild fish and also came to be considered as a good experimental fish. Oreochromis mossambicus Oreochromis mossambicus or Mozambique tilapia was originally imported from Indonesia by the Japanese in 1944, when Taiwan was still under the Japanese occupation. However, its culture failed. In 1946, it was brought back into the country under rather peculiar circumstances, and not as a deliberate introduction for scientific research or culture purposes. Two Taiwanese men named Wu and Kuo had been commissioned as Japanese soldiers during the Second World War. When the war was over, and they were released from military service, they returned home to Taiwan with several 0. mossambicus which they took from Singapore as souvenirs, of which 13 survived. Since then, this species of tilapia was cultured successfully and became very popular in Taiwan. In memory of its "accidental" introducers, it was called "Wu-Kuo yu", yu being the Chinese word for fish. It is true that this species has a number of weak features. For instance, it is not very resistant to low temperature, it spawns too fast, and when it matures, its color turns black, making it quite unattractive and not so acceptable to consumers. But because it grows fast, produces a high yield, and is a sturdy fish, it was readily accepted by the Taiwanese fish farmers and consumers as a cheap and available source of protein immediately following World War II. This fact is to be

114 appreciated in the context of the widespread poverty and hunger, which were the aftermath of the war. Other specimens were imported in 1981 from the Republic of South Africa (RSA) for the purpose of studying cross-breeding. In Taiwan, this species was initially crossed with 0. niloticus male. The result is a popular hybrid with rapid growth, large size and much better appearance (Kuo 1969). The Taiwanese call this hybrid "fu so yu", fu so meaning "lucky, longlife". 103 Salmo gairdneri Salmo gairdneri or rainbow trout was first introduced from Japan in Three thousand fertilized eggs of this species were released into a reservoir, where most probably perished. In 1959 and 1960, 200,000 'eyed' eggs were introduced (each year), but again, all perished. Finally, in 1961, 50,000 'eyed' eggs were imported, hatched and reared to adult stage at Ma-Lin, a research station of the Lukang Branch of the Taiwan Fisheries Research Institute TFRI) (Chen 1976). This hatchery has been in operation from that time until the present. Aside from this research hatchery, a number of commercial hatcheries for this species also currently exist in Taiwan. The difficulties encountered in its culture in Taiwan have to do mainly with the need for an adequate cold water supply. It commands a good price, but the volume of production is limited by the lack of appropriate culture areas, i.e., those with abundant supply of cold water, and this also limits expansion. Tilapia zulu Introduced from RSA in 1963 by Tang, Tilapia zulu or redbelly tilapia never gained much popularity due to its small size, slow growth and aggressive behavior towards other fish (Chen 1976; Liao and Chen 1983). Also, it does not taste very good and is not suited for polyculture. The main reason for its introduction was to cross-breed it with 0. rnossambiciis. T. zulu is relatively cold-resistant as compared with 0. mossambicus, and it was hoped that a more coldresistant hybrid would result. Sixteen fish had been introduced but the species never did become popular for culture. 0. niloticus 0. niloticus or Nile tilapia was introduced from Japan by Yu and Imai in 1966 (Chen 1976; Liao and Chen 1983). Fifty-six individuals were originally introduced. By itself, 0. niloticus makes a fine culture species, and it also produces good results when crossed with 0. mossambicus. But so far, the best result is achieved when it is crossed with 0. aureus males; predominantly male and much larger offspring are produced.

115 104 Pangasius sutchi Pan gasius sutchi or pangasius catfish was introduced from Thailand in 1969 by Ling (Chen 1976). It cannot tolerate the cooler climate of Taiwan, but it has high tolerance for low oxygen content. It is quite palatable and larger than the local species of catfish, Clarias fuscus. Also, it has a very efficient conversion rate, even if it is given only tilapia feed. However, its acceptability has suffered somewhat because people mistake it for the sea catfish, Anus maculatus (Thunberg), which closely resembles it in appearance, but which is of much poorer quality. After its introduction, it was experimentally cultured at a government-run pilot farm. At present, though, it has come to be used more as an ornamental fish than a food fish. Clarias batrachus Clarias batrachus or walking catfish was introduced in 1972 from Thailand (Chen 1976). It is known for its fast growth rate. One fish can reach up to 2 kg in one year. Although C. batrachus is also generally regarded as a pest (Welcomme 1984), it has nonetheless achieved considerable popularity. It has apparently cross-bred with the native species C. fuscus, resulting in a hybrid that has spread all over Taiwan, to such an extent that C. fuscus is now in danger of extinction. 0. aureus 0. aureus or blue tilapia was introduced from Israel in 1974 by Liao, Huang and Tseng with the assistance of Pruginin (Chen 1976; Liao and Chen 1983). The 83 specimens imported were intended for obtaining all-male offspring when crossed with 0. niloticus females. The resulting hybrid is now the tilapia mainly cultured in Taiwan; it provides a fine example of success achieved with exotic aquatic species. Annual production of this hybrid currently.exceeds 50,000 tonnes. Ictalurus punctatus Ictalurus punctatus or channel catfish was introduced from the U.S.A. in the mid 70's. However, the warmer climate in Taiwan is not very suitable for its culture. It is also very sensitive to water quality, such as that resulting from pollution. Not being so popular, this species is no longer cultured. Anguilla anguilla Anguilla anguilla or European or French eel was introduced to Taiwan around 1976 (Chen 1976). It is native to Europe and at the time of its introduction, it was considered as a promising species for culture. Although A. japonica, the native species, is a good culture species, and the technology for raising it was well understood by the local aquaculturists, the inability to produce adequate quantities of this species prompted the introduction of A. anguilla.

116 However, A. anguilla cannot tolerate the high temperature in Taiwan and has been infected by many diseases and parasites, resulting in its slow growth. Survival rate under culture was usually low. As a result of these disadvantages, prospects for the culture of this species locally are not very bright. 105 Leptobarbus hoevenii Leptobarbus hoevenii, also known as barb or sultan fish, was introduced to Taiwan in 1979 from Indonesia. Currently, it is being experimentally cultured at the Lukang Branch of TFRI. Another species, which has not yet been identified, but which could be L. hosei, was also introduced at a later date. It is smaller than L. hoevenii, but is much easier to mass produce. Because of this, it has attracted the interest of many aquaculturist. Megalobrama amblycephala Megalobrama amblycephala or Wu-chang fish was introduced from mainland China in 1979 and generally remained unpopular among culturists. Another Megalobrama species may have been inadvertently introduced, although it has not yet been identified. Both species are so bony and thus are not very much appreciated by local consumers. Lately, M. amblycephala has been used for cross-breeding with the Ctenopharyngodon idellus. Micropterus salmoides A fish native to North America, Micropterus salmoides or largemouth bass was introduced to Taiwan in the late 70's. In other countries where M. salmoides has also been introduced, it was reported to have endangered or actually caused the extinction of certain indigenous species. In Taiwan, however, the techniques for artificial propagation of M. salmoides have been established and improved, and this fish has rapidly gained popularity. Much care has been taken so that this fish is used only for monoculture, and not stocked in natural waters. M. salmoides was easily accepted and liked by Taiwanese consumers. At present, it is cultured in several places in Southern Taiwan and is even exported to Hong Kong. Red tilapia There is a local red tilapia strain in Taiwan, which is different from and should not be confused with the exotic Oreochromis sp. Thirty specimens of the latter were introduced in 1979 by Liao, Chao, Chen, Huang, and Liu, with the assistance of Yeh, from the Philippines, where it is also exotic (Liao and Chen 1983). This exotic Oreochromis strain was introduced here to be used in genetic studies and cross-breeding.

117 hornorum This species is also known as wami tilapia. It was introduced from Costa Rica in 1981 by Huang and Yeh. The objective of the introduction was to obtain monosex progeny by hybridization with other Oreochromis spp. All the hybridization attempts have been successful in producing all-male offspring, and the hybrids are now being used for extension. However, these hybrids are smaller in size than 0. niloticus and 0. aureus hybrids. T. rendalli T. rendalli or red breast tilapia was introduced from RSA in 1981 by Liao, Sch.00nbee and Clark (Liao and Chen, 1983). All 25 specimens were introduced for the mere purpose of adding a new species to the local gene pool. Colossoma bidens Colossoma bidens or freshwater pompano was introduced from Brazil probably around It is currently being cultured experimentally and appears promising. However, there is often a negative impression of this fish because of its similarity to the aggressive piranha, Pygocentrus piraya, and this can hamper its extension. Sciaenops ocellatus Sciaenops ocellatus or red drum was introduced in 1987 by Liao, Huang, Lee and Arnold from the United States. This species has an impressive growth rate, and although it is still in an experimental stage of culture, it shows much promise. Cyprinidae The following cyprinids are generally believed to have been introduced several centuries ago from mainland China, although exact dates of introduction were not recorded. Aristichthys nobilis or bighead carp Carassius auratus or crucian carp Cirrhina molitorella or mud carp Ctenopharyngodon idellus or grass carp Hypophthalinichthys molitrix or silver carp Mylopharyngodon piceus or snail carp. Collectively, they are referred to as the "Chinese carps". The year 1963 was a milestone in Chinese carp culture; during that year, Taiwan succeeded in devising the techniques for induced spawning of these Chinese carps. Prior to 1963, they had to be introduced yearly from mainland China, through Hong Kong, because fry were always in short supply. Another carp, Cyprinus carpio or common carp, was introduced long ago from Japan and is also being commercially monocultured.

118 Today, most of these carps are polycultured commercially with considerable success, and their fry are exported in substantial volumes. Annual production of all these carps, put together, is currently 30,000 t. 107 Macrobrachiusn rosenbergii Crustaceans Macrobrachium rosenbergii, also known as Malaysian prawn or giant river prawn, was introduced in 1970 from Thailand by Ling. From one male and one female, the only survivors from the entire shipment, thousands have been bred, spurred by the success achieved at the Tungkang Marine Laboratory (TML) of TFRI (Liao et al. 1973). This has facilitated the development of a relatively successful enterprise. Its monoculture makes up a big industry. Lately, M. rosenbergii has peculiarly become a popular species for game fishing in Taiwan. Penaeus stylirostris Penaeus stylirostris or blue shrimp was introduced from Panama in 1979 by Perysn and Lee (Liao and Chao 1983). It was the first saltwater prawn species introduced to Taiwan. Of the 500,000 nauplii introduced, 50,000 were brought to TML, where they were successfully reared to the adult stage. However, there were difficulties met on inducing it to mate. As a result, this species has become extinct. P. vannawi P. vannamei or white leg shrimp was the second exotic shrimp introduced to Taiwan. In 1981, 86 young P. vannamei were brought by Huang from Panama. Although this species grows well in Taiwan, it is hard to induce the shrimp to mate in captivity. Furthermore, this species is known to have latent infectious hypodermal and hematopoietic necrosis or IHHN (Bell and Lightner 1984), and this presents potential problems. Thus, care must be taken to identify the source of the P. vannamei introduced. P. brasiliensis P. brasiliensis, also known as red spotted shrimp or Guiyana pink, was introduced in 1981 by Liao and Chao with the assistance of Instituto de Pesquisas de Marinha and Chang of Brazil (Liao and Chao 1983). Its culture has been intensively experimented, though only a size of 40 g was attained after a one-year growout (Liao and Chao 1983). Unfortunately, there are no more surviving P. brasiliensis in Taiwan.

119 108 P. schmitti P. schmitti or southern white shrimp has been introduced from Brazil by Liao and Chang and is experimentally cultured. Unfortunately, efforts to propagate this species have failed. Achatinafulica Molluscs Achatinafulica or giant African snail was introduced from Singapore in This species has propagated and has become a pest to agriculture. Ampullarius insularum The mollusc Ampullarius insularum or apple snail was introduced into Taiwan in 1979 from Argentina. It was adopted for culture, but it has become more of a pest. Its eggs, conspicuously coloured bright red, now seem to be found in almost any body of water in Taiwan, creating a considerable problem when they hatch, because they cause widespread damage to ricefields. Laminaria japonica Seaweeds Laminaria japonica, also known as kelp or konbu, was first introduced from Japan in Currently, it is cultured in small scale, mainly in the northern part of Taiwan. Undaria pinnatifida and U. undaroides Undaria pinnatijlda and U. undaroides or wakame were introduced from Japan in 1981 by Chiang. They are now commercially cultured in Quemoy and Peng-hu islands as well as in northern Taiwan. Both species show bright prospects for interested culturists. Rana catesbeiana Reptiles In 1924, before World War II, when Taiwan was a Japanese-occupied territory, the Japanese introduced the Rana catesbeiana or American bull frog to Taiwan. The first introduction was not successful because the farmers who reared the frogs became discouraged and abandoned the project. After the war, in 1951, it was reintroduced from Japan by TFRI and distributed to interested farmers. The attraction of frog culture is that little capital investment and space are required. Thus the interest could be shared by rural and city dwellers. Rana catesbelana has now become a very popular culture species.

120 109 Caiman latirostris and Alligator mississippiensis Caiman latirostris or caiman is commercially cultured in Taiwan under intensive conditions. Alligator mississippiensis or alligator is also commercially cultured, but under semi-intensive conditions. Both of these reptiles are already part of a budding industry in Taiwan and probably hold good prospects for the future. Usefulness of introductions Discussion When properly planned, recorded, documented and managed, introductions of exotic aquatic species can be very beneficial. One successful introduction in Taiwan (aside from the tilapias) involves Plecoglossus altivelis - that is, assuming it falls under the definition of "exotic" or "introduced" species. It was originally a native species in Taiwan, but as a result of manmade damage to its environment, the populations decreased greatly, and eventually, this species disappeared completely. Eyed eggs were then introduced from Japan and under the guidance of research institutes and the protection of game fishing clubs, Taiwan's reservoirs and rivers were once again restocked with P. altivelis. Several other species, such as M. rosenbergii and R. catesbeiana, are also very popular and commercially important. Before the recent heavy industrialization of Taiwan, these species helped in improving the social and economic conditions of a big number of aquaculturists. The culture of these species had a very visible social impact on the country. Their popularity and commercial viability are also demonstrated in other parts of the world. Exercising caution Many other exotic species, out of the 38 mentioned above, turned out to be successful introductions. These species have the proven qualities for culture in most conditions and are generally quite popular. One important factor which enhanced the success of these introductions was the careful and systematic process in which they were carried out. Without such careful testing, the consequences could be quite detrimental, as in the case of the two snails, Achatina fulica and Ampullarius insularum. However, caution must still be exercised, even with successfully introduced species. The case of the tilapias is an example of the benefits and dangers of introduced species. Although the tilapias offer many advantages as a culture species, and most tilapia introductions into Taiwan (see Table 2) have been successful, it is important to note that tilapia introductions into other countries have been blamed for the transfer of certain parasites. For instance, six species of Cichlidogyrus (gill flukes) were transferred from Africa to Israel as a result of tilapia introductions (Hoffman and Schubert 1984). This is a potential threat and should be considered whenever tilapia is being introduced. Furthermore, 0. mossambicus, T. rendalli and T. zulu are generally regarded as pests when introduced as exotic species (Welcomme 1984). Another species which should be regarded with caution when being considered for introduction is the S. gairdneri. The introduction of S. gairdneri can be somewhat controversial, since this species has been associated with the spread of furunculosis. This disease is thought of

121 110 to be native only to S. gairdneri of western North America. After introductions of S. gairdneri, furunculosis became a serious problem in European brown trout. Now, this disease can be found in most places where salmonids are cultured (Welcomme 1984). S. gairdneri is also known to be a carrier of Myxosoma cerebalis (Hoffman and Schubert 1984), a virulent parasite, which can survive in extremely low temperatures. It remains as a threat even if the carrier is already frozen. A danger such as this would warrant even more care to prevent the spread of an unwanted parasite that may do much damage to local species. Inadequate documentation The documentaticn of introductions, even of the successful ones, has general:ly not been satisfactory. However, solving this problem may not be as simple as it seems. Some naive aquaculturists may introduce a potentially harmful species, unaware of the ecological effects of such an action, while unscrupulous traders or businessmen may do the same, quite deliberately, even with full knowledge of the detrimental consequences. In either case, the proper authorities are usually left uninformed of the introduction and thus, an already difficult problem is compounded. Ecological pact Inadequate documentation, itself an already complex problem, leads to an even more serious problem - the inability to monitor the impact of unrecorded exotic species on the native ecosystems. The danger of this lack of information and knowledge is that some of the species introduced could actually assume dominant niches in the natural ecosystems which may, over time, prove detrimental. Although most, if not all, are maintained in very controlled environments, the number that may escape these environments would not be easy to trace. There are still other exotic species not discussed in this report, for lack of data, but which are strongly suspected to have caused damage to the populations of some indigenous fishes. Among these "controversial" exotics are Poecilia velafera, which has endangered the native species Rhyacichihys aspro and Mesopristes cancellatus, and Tricogasrer trichopterus, which has endangered Capoera semfascio1ata (see Table A.IIl). Sometimes, because of unmonitored or unrecorded introductions, the scientific names of some species which have been brought in could not even be determined. With all these unidentified exotic species coming in to Taiwan, the task of studying the ecological impact of these species becomes even more complicated for fisheries scientists and authorities. In Taiwan, the tilapias were introduced by research institutes. Fisheries and aquaculture scientists studied them carefully before disseminating them among the interested farmers. Screening and meticulously experimenting on these exotic species before releasing them for commercial culture have helped prevent environmental and other problems. It enabled the researchers to gather valuable information regarding the ecology of these species, and therefore also enabled them to provide the necessary instruction to the people interested in the culture of tilapia.

122 111 Conclusions The case of the tilapias and that of P. altivelis exemplify the usefulness of well controlled introductions. However, two or several favorable cases are not enough. The problem on the lack of information on exotic aquatic species in Taiwan still remains, and calls for a more determined effort to maintain a record of all introduced species through a centralized system. A more vigorous educational campaign should be undertaken by agencies, both private and governmental, concerned with aquatic resources. Intensive research on introduced species should be conducted before their dissemination throughout the aquaculture industry. Quarantine procedures must be made more efficient and must be implemented more effectively. Only in these ways may it be possible to start to minimize the incidence of illegal or unmonitored introductions and other related problems. The proper planning and implementation of exotic introductions are difficult to carry out successfully without cooperation among countries. Information must be shared and exchanged between and among nations and mutually beneficial agreements must be forged, such as that established at the Convention on International Trade in Endangered Species of Wild Fauna and Flora, more popularly known as the "Washington Conventiont'. The workshop on exotic species organized by the Asian Fisheries Society in June of 1988 was a meaningful move to address the issue. It is hoped that this initiative will be followed up and continued by the same and other organizations. Acknowledgement The authors thank the following people who, in one way or another, have helped in the preparation of this report: Mr. R. Lazo, Mr. C.Y. Liu, Ms. M. Carigma, Ms. F. Lucero, Mr. W.Y. Liu, Mr. T.A. Lee, Mr. C.S. Tzeng, Mr. T.C. Yu and Mr. H.C. Yang. References Bell, T.A. and D.V. Lightner TERN virus: infectivity and pathogenicity studies in Penaeus.rtylirostris and Penaeus vannamei. Aquaculture 38: Chen, T.P Aquaculture practices in Taiwan. Fishing News Books Limited, Famham, Surrey, England. 161 p. Hoffman, G.L. and G. Schubert Some parasites of exotic fishes, p In W.R. Courteney, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A. Kuo, H Notes on hybridization of tilapia. JCRR Fish. Ser. 8: (In Chinese with English abstract?) Liao, IC. and N.H. Chao Development of prawn culture and its related studies in Taiwan, p In G.L. Rogers, R. Day and A. Lim (eds.) Proceedings of the First International Conference on Warm Water Aquaculture-Crustacea. Office of Continuing Education, Brigham Young University, Hawaii Campus, Hawaii, U.S.A. Liao, IC. and T.P. Chen Status and prospects of tilapia culture in Taiwan, p In L. Fishelson and Z. Yaron (eds.) Proceedings of the International Symposium on Tilapia in Aquaculture, 8-13 May Nazareth, Israel. Liao, IC., N.H. Chao and L.S. Hsieh Preliminary report of the experiments on propagation of giant freshwater prawn, Macrobrachiwn rosenbergii in Taiwan. J. Fish. Soc. Taiwan 2(2): McCann, J.A Involvement of the American Fisheries Society with exotic species, p In W.R. Courtenay, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A. Welcomme, R.L International transfers of inland fish species, p In W.R. Courtenay, Jr. and J.R. Stauffer, Jr. (eds.) Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, U.S.A.

123 Table 1. Exotic species introduced into Taiwan. Scientific Name Common Name Area of Origin Date of Importation Production for 1987* (t) Culture Status FINFISH Gambusia affinis Topminnow North America Popular; monocultured Oreochrom,s Mossambicus Mozambique ulapia Indonesia 1944 See Table 2 Widespread Salmo gairdneri Rainbow trout Japan Cold water, supply limits expansion; monocultured Tilapia zulu Redbelly tilapia South Africa 1963 See Table 2 Unpopular 0. niloticus Nile tilapia Japan 1966 See Table 2 Popular, used to culture a hybrid with 0. mossambicus females Pangasius sutchi Thailand catfish Thailand 1970 Unpopular, polycultured Clarias batrachus Walking catfish Thailand 1972 ** Popular 0. aureus Blue Lilapia Israel 1974 See Table 2 Crossed with 0. nibticus female to obtain all male offspring Ictalurus punctatus Channel catfish U.S.A. mid ** Unpopular 1970's Anguila anguilba European eel Europe Culture discontinued Leptobarbus hoevenii Barb or sultan fish Indonesia Unpopular; not easy to breed Megalobrama amblycephala Wu-chang fish Mainland China Unpopular, mono- and polycultured u;,-,.,.,,t,,,.,,,.,.,, I.,.,,,d.,. I -,,,,I,,,.4, A.-.,., 1970's Pnnn1r mnnociiltnred Continued

124 Table 1. Continued Scientific Name Common Name Area of Origin Date of Importation Production for 1987* (t) Oreochromr sp. Red tilapia Philippines 1979 See Table 2 0. hornorwn Wami tilapia Costa Rica 1981 See Table 2 T. rendalli Red breast tilapia South Africa 1981 See Table 2 Colossoma bidens Freshwater pompano Amazon 1986 South America Sciaenops ocellatus Red drum U.S.A Aristichthys nobilis Bighead carp Mainland - China Carassius auralus Crucian carp Mainland China and Japan 2,899.6 Cirrhina molitorella Mud carp Mainland China Ctenophaiyngodon idellus Grass carp Mainland China 10,031.1 Hypophthalmichthys molitrix Silver carp Mainland China 9,89l.9*** Mylopharyngodon piceus Snail carp Mainland China Cyprinu.s carpio Common carp Japan before 4, Culture Status Used for genetic studies and crossbreeding Used to obtain monosex progeny by hybridization Used to add new species Promising; monocultured Experimental Important culture species withe exportation of fry; polycultured Mass produced; polycultured Important culture species with exportation of fry; polycultured Important culture species with exportation of fry; polycultured Important culture species with exportation of fry; polycultured Important culture species with exportation of fry; polycultured Mass produced; polycultured Continued

125 Table 1. Continued Scientific Name Common Name CRUSTACEANS Macrobrachiwn rosenbergii Giant river Penaeus slylirostris Blue shrimp P. vannamei White leg shrimp P. brasiliensis Red spoiled shrimp P. schmilti Southern white shrimp MOLLUSCS Acha!inafidica Giant Msican snail Apullarius insularwn Apple snail SEAWEEDS Laminariajaponica Kelp or konbu Undaria pinnati Ida Wakame U. undariodes REPTILES Rana catesbeiana American bull frog Alligator mississippiensis Alligator Caiman latirostrlr Caiman * Estimates by the Taiwan Fisheries Bureau. ** Total production for the three species of catfish is t. This is the total production for both bighead carp and silver carp. Area of Origin Thailand Panama Panama Brazil Brazil Argentina Japan Japan Japan Japan - Date of Importation Production for 1987* (t) 1,354.0 Culture Status Mass produced; vesy popular, monocultured Experimental Experimental; will not mate in captivity Production reached fourth generation Major agricultural pest Major agricultural pest Not cultured Commerciaily cultured Commercially cultured Popular; monocultured Commercially cultured Commercially cultured

126 Table 2. Record of tilapia introductions to Taiwan. Species Year Area of Origin Introducer Assisted by by Number introduced Oreochromss mossambi cur 1944 Indonesia 0. mossambicus 1946 Singapore Wu & Kuo 13 Tilapia zihii 1963 South Africa Tang 16 0.,ulolicus 1966 Japan Yu lrnai aureiss 1974 Israel Liao, Huang Pruginin 83 & Tseng Ore ochromss sp. (Red tilapia) 1979 Philippines Liao, Chao, Chess, Huang, & Liu &jsg hornorum 1981 Costa Rica Huang Yeh mossambicus 1981 Costa Rica Huang Yeh 4 0.mo,ysambjcus 1981 SouthAfrica Liao Schoonbee 50 & Clark T. rendalli 1981 South Africa Liao Schoonbee 25 & Clark 0. ruloticus 1984 France Liao& Serene 690 Chao O.aw-eur 1984 France Liao& Serene 170* Chao 36** 0.massambicur 1984 France Liao& Serene 40 Chao Total production of tilapia for 1987 exceeds 100,000 t. * Israeli strain. Filipino strain. Purposes Extension and Cultural Status To increase the supply Unsuccessful of animal protein during WWII Brought back out of Widely spread curiosity by 2 returning soldiers from SE. Asia To be used in pro- Well spread because it is cold ducing cold-re- resistant; hard to polycuhure sistant hybrid Introduced for culture Well accepted especially its large iisd hybridization due size resulting from a cross with 0. to its large size mossambicus female Hybridization Well accepted especially when crossed with 0. niloticus female Genetic studies and Maintained at Tungkang Marine Lab.; cross breeding not ready for extension To obtain monosex Not ready for extension progeny To be used in cross Not ready for extension breeding studies Tobeusedincross Notreadyforextension breeding studies To add new species Not ready for extension Tomaintainnew Underhybndizationstudy strain Tomaintainnew Underhybsidizationstudy iin Tomaintainnew Underhybridizationstudy strain

127 116 Abudefdufoxyodon Abudefdufstarcki Abudefdufmelanopus Acanthophthalmus semicinctus Acanthopsis choirorhyncus Acanthurus leucosternon Achirus errans Adioryx spinosissimus Aeoliscus strigatus Aluteres scripta Alestes taeniurus Ambassis lala Amblydoras hancockii Amphiprion biaculeatus Amphiprion clarkii Amphiprionfrenatus (Brevoort) Amphiprion ocellaris cuvier Amphiprion perideraion (Bleeker) Amp hiprion parasema Amphiprion polymnus Amphiprion sebae Anoptichthysjordani Aphyocharax rubropinnis Aphyocyprinus sp. Aphyosemion australe Aphyosemion bivittatzim Aphyosemion calliurmahli Aphyosemion sjoestsdti Aphyosemion arnoldi Apistogramma ramirezi Aplocheilus dayi Apogon macularus Apogon orbiculatus Apteronotus albifrons Arapaima gigas Arnoldichthys spilopterus Aulonocara nyassae Bacantiocheilus melanopterus Badis badis Balantiocheilus melanopterus Balistoides conspicillum Barbodesfasciatus Barbus everetti Barbusfasciatus Barbus lateristriga Barbus nigrofasciatus Barbus schwanefeldi Barbus semfasciolatus varia Barbus tetrazona Barbus titteya Betta splendens Bodianus amthioides Bodinus loxozonus Botia horae Annex I LIST OF AQUARIUM FISH INTRODUCED INTO TAIWAN Botia lecontei Botia macracantha Botia modesta Botia pulchripinnis Brachydanio albolineatus Brachydanio nigrofasciatus Brachydanio rerio Brachygobius xanthozona Brycinus longipinnis Calloplesiopa altinelis Callochromis pleurospilus Capoeta tetrazona Carnegiella strigata Centropyge argi Centropyge bicolor Centropygeferrugatus Centropygefisheri Centropyge loriculus Centropyge multicolor Centropyge nox Centropyge potteri Cephalopholis urodlus Chaetodermis spinosissiums Chaeron ephippiwn Chaeton ocrofasciatus Chaeton quaddimaculatus Chaeton rainfordi Chaeton reticulatus Chaeton sp. Chaetodontoplus duboulayi Chaetodontoplus mesoleucus Chalinochromis brichardi Chanda ranga Cheirodon axelrodi Chelmo rostratus Chilodus purl ctatus Chiloscyllum colax Chrysiptera starki Cichiasoma salvini Colisa chuna Colisafasciatus Colisa labiosa Colisa lalia Condylactis sp. Corisfulis Corydoras metae Corynopoma riisei Cromileptes altivelis Cynolebias bellouii Cynotilapia afra Gyp hotilapiafro ntosa Daino malabaricus Dascyllus aruanius Continued

128 117 Annex I. Continued Dascyllus melamurus Dascyllus resticulatus Dasyatis kuhlii Dendrochirus zebra Diane,na longibarbis Diploprion bifascarum Distichodus lusosso Distichodus sexfasciatus Ecsenius bicolor Eigenmanni virescens Enoplometopus occidentalis Epaizeorhynchus kallopterus Epinephelus tauvina Eretmodus cyanostictus Esomus malayan Euxiphipips sextriatus Euxiphipips nevarchus Euxiphipips xanthometopon Flamneu sammara Gasteropelecus levis Gasterosteus aculeatus Gate rin chaetodonides Genicanthus larmark (Lacepede) Geophagus thayeri Gobiodon specie Glymmistes sexlineatus Gnathonemus macro lepidotus Gnathonemus petersi Gymnocorymbus ternetzi Gyrinocheilus aymonieri Ha/ic hoeres chrysus Hapalochlaena maculosa Haplochromis desfontainesi Haplochromis linni Helosrorna rudoiphi Helostoma iemmincki Hemigrammus gracilis Hemigrammus ocellfer Hemigrammus pulcher Hemigrammus rho dpstomus Hemiodus gracilus Hemiodus semitaenitatus Hemitaurichthys polylepis Hippocampus coronatus Hippocampus keliggi Hippocampus specie Holacanthus arc uatus Ho/acanthus ciliaris Holacanthus clarionensis Holacanthus isabelita Holacanthus passer Ho/acanthus tricolor Hymenocera sp. Hoiplolatilus purpureaus Hyphessobrycon callistus (Callistus callistus) Hyphessobrycon callistyus rosaceus Hyphessobryconflammeus Hyphessobrycon herbertaxeirodi Hyphessobrycon heterorhabdus Hyphessobrycon innesi Hyphessobrycon pulchripinnis Hyphessobrycon rubrostigma Hyphessobrycon scholzei Hypostomus sp. Hypseleo iris compressa Julidochromis transcriptus Julipocheromis transcriptus Krypropterus macrocephalus Labeo bicolor Labeo erythrurus Labeo frenatus Labeo numensis Labeotropheus trewavasae Labroides dimidiatus Lactoria cornua Lamprologus co,npressicep Lamprologus leleupi Lebistes reticulatusi Lebrasoma reliferum Lepisosteus oculatus Lepomis megalotis Leporinusfasciatus Lienardellafasciata Lima scabra Lo vulpinos Loricariafilamentoa Lutjanus sp. Macro gnat hus aculeatus Macropodus opercularis Maso literatus Mastacembelus maculatus Mesogonistlus chaetodon Merynnis schreitmullerii Microlabichthys tukapascalus Microp his smithi Moenkhausia oligolepis Mogurnda mogurnada mogurnd Continued

129 118 Annex I. Continued Mollienisia sphenops (latipinna) Momadactylus argentens Monodactylus sebae Muraena pardalis Mylossorna duriventris Nannostomus anomalus Nemaptereleoteris magnficus Nemateleotris specie Neosilurus ater Neopetrolisthes ohshimai Notopterus chitala Opistognathus aurifons Opistognathus whitehurstii Osphronemus goramy Osteochilus vittatus Osteochilus hasselti Osteoglossum bicirrhosum Osteoglossumferreirai Oxymonacanthus Ion girostris Pamacanthus imperator Pan gastus sutchi Pan que nigrolineatus Pantodon buchholz Parambassis gulliveri Pelotropoma melanoleucus Peocilabrycon aqratus Phenaxorgammus interruptus Pholidichthys leucoraenia Pimelodus clarias Platax teira Platax pinnatus Plecostomus punctatas Poecilia latipinna Poecilobrycon aura tus Poecilobrycon puctatas Pogonoculius zebra Polycentrus shomburgki Polyodon spat hula Pomacanthus annularis Pomacanthus arcuatus Pomacanthus chrysurus Pomacanthus coeruleus Pomacanthus imparotor Pomacanthus maculosus Pomacanthus paru Pomacanthus zonipec tus Premnas biaculeatus Prevagor melanocephalus Pristella riddlei Prochidodus amazonensis Prochidodus insignis Prochidodus taeniurus Pro gnathodes aculeatus Pseudobalistisfuscus Pseudotropheus sp. Pterois antennata Pterophyllum eimekei Pterophyllum hecker Purple chromis Pygolites diacanthus Rasbora borapetensis Rasbora dorsiocellata Rasbora heterornorpha Rosbora maculata Rasbora trilineata Rhinomurena amboinensis Rhynchocinetes sp. Scolcpsis sp. Scorpaenodes littoralis Selenotoca multifasciata Serranus spilurus Shaerichthys osphrornenoides Siganus vulpinus Spilotichthys picturatus Stenopus hispidus Symphysodon aquifasciata Symphysodon discus Synaphobranchus sp. Synchiropus splendidus Syngnathus boversi Snodontis angelicus Synodontis davidi Tamichihys albonubes Telmatherina ladigesi Thayeria boehlki Thayeria sanctaemariae Toxotes jaculator Trichogaster leeri Trichogaster trichopertus Trichogasrer trichopertus (surnatranus) Trichogaster microlepis Triportheus elongatu.s Tropheus duboisi Uara amphiacanthoides Xanthichthys species Xiphophorus hellerii Xiphophorus maculatus Zebrasona veliferum Zebrasoma scopas

130 Exotic Aquatic Species in Thailand TWESUKDI PIYAKARNCHANA Department of Marine Science Faculty of Science Chulalongkorn University Bangkok, Thailand Piyakamchana, T Exotic aquatic species in Thailand, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154p. Asian Fisheries Society, Manila, Philippines. The first record of an exotic aquatic species in Thailand can be traced back to Ayudhaya period of about the year At present there are about 15 species of fishes which were introduced for aquaculture purposes. Among them only a few are confirmed as reproducing in the natural habitats. The exotic species in the aquarium trade on the contrary were reported to increase rapidly from 69 species in 1963 to about 92 in Only 3 fish diseases were recorded to come from these exotic species. Records on the real impact to the natural ecosystem from the introduced species are scarce. The introduction of exotic fish into Thailand dates back to the Ayudhaya Period probably around the years (Amatayakul 1957). However, not until 1953, was a royal decree, which prohibited the introductions of many exotic species of animals and plants, proclaimed and implemented. The purposes of introducing exotic animals and plants into Thailand are at least three fold; for consumption, for aquaculture, and for home aquarium and exhibition purposes. The major countries from which these exotic animals are exported into Thailand are Japan, Indonesia, Singapore, Sri Lanka, Taiwan, Hongkong, Philippines, Burma and The United Kingdom. Some countries frequently act as middlemen. At present, the trading aquarium exotic species, especially fish, is very popular in Thailand. Historical Background There are three periods in which the exotic aquatic animals were introduced into Thailand. The first period was before 1953 in which three species of Chinese carps, grass, bighead and silver carps were introduced, mostly by the Chinese immigrants, for aquaculture purposes. These fish carried parasites such as anchor worm (Lernaea sp.) cotton wool disease (Saprolegina sp.), and fish louse (Argulus sp.). These fish, in the latter dates, were widely spread all over the country, and the parasites and associated diseases spread with them. There are no reliable records on the degree of the destruction by these diseases to the native species. The second period was during This period was based on the time of the first proclamation of the Royal Decree called "The Prevention on the introduction of certain freshwater fishes, 1953." 119

131 120 This decree prohibited the introduction of cyprinids into the country without permission. It also required the introducer to present evidence that they were free from certain diseases. The third period is from 1983 to the present time. There was an amendment of the Royal Decree in 1982 and it was made law in The main reason for this amendment was to stop the wide outbreak of the so called "ulcerous fish diseases" in this country during The diseases which were found to be caused by certain viruses suspected to have been introduced through exotic aquarium fish. The decree which is still in use prohibited the introduction of aquatic organisms of freshwater and marine origin. They include the following: Fish species. Other aquatic animals (e.g., crabs, corals, molluscs and others) - 21 species. Algae - 16 species. Aquarium Purposes Introductions A compilation of exotic aquarium species is given in Tables la and lb. Because of the insufficient records available from Government agencies and the private sector, information is not available on the dates and country of introduction, and it is impossible to complete the list and details of historical and the present status of most species. The first record on 1)0th local and introduced fish species was made by Chuensri (1963). Among these exotic fishes, the goldfish (Carassius auratus) is claimed to be the oldest. It had been introduced in Thailand (then called Siam) in , during the Audhaya Period (Amatayaku 1957). The second introductory period of the aquarium fishes started about 70 years ago. The Fisheries Department, Ministry of Agriculture and Cooperative, and the Ministry of Public Health, jointly introduced the mosquito eating fishes (Gambusia spp.), for malaria control. This species is now widely distributed in natural waters especially in the urban region of the big cities in Thailand. It is also recognized that of all exotic fishes, the cichlids are the most popular. The second priority are those of the Family Cyprinidae. For Aquaculture Purposes Of the 36 species of fishes cultured in Thailand, about 15 species are introduced, and are listed in Table 2. It could be dated back to the year 1912 when common carp, Cyprinus CarplO was introduced from China. The Chinese grass carp (Ctenopharyngodon idellus) and bighead (Aristichthys nobilis) were introduced by Chinese immigrants in At least two species e.g., trout (Salmo gairdneri) and Amago salmon (O,i.chorhynchus rhodurus) were introduced to Thailand for experimental purposes in the highland development project in the northern part of Thailand.

132 121 Present Status of the Exotic Species The present status of the exotic species are classified at different levels. Those species that are used for aquaculture such as the two species of tilapias (Oreochromis mossambicus and 0. niloticus) are now well established in the ecosystem of Thailand. They are completely viable. 0. niloticus is more popular as food than the other. Common carp is also known to breed in natural waters. Among the three species of the Chinese carps, which are successfully grown in aquaculture systems, none of them breed naturally. Of the aquarium exotic species, few successfully breed naturally and the rest are bred artificially. In some species for example, a black tetra of black kamoor, (Gymnocorymbus terneizi) and a Jack Dempsey (Cichiosoma biocellatum) were first imported from South American countries (Paraguay, Bolivia and Argentina) and in 1950s reintroduced from Hongkong and Japan. They breed successfully in the natural habitats of Thailand. Recorded Ecological Effects Surprisingly, there are very few documented ecological effects by introduced species in Thailand. The author observed that 0. mossarnbicus is a nuisance species and even considered it as a bottom surface competitor to the brackish water shrimp e.g., Penaeus merguiensis, in culture ponds. A species of American freshwater crayfish (Procambrus clarkii) and a cherry snail, Ampularia gigas were suspected by some freshwater prawn culturists to be the cause of the stem damages of rice in the paddy fields. It was also suspected that the introductory American bull frog, (Rana catesbina) might be harmful to the local species of frogs (Ta Yoo 1986). Four exotic aquatic plants were reported by Santi (1986) and Tandaraporn (1962): Echimodorus peruensis or the Peruvian sword or black amazon sword, Cabomba caroliniana, Najas indica and Potamogeton crispus. These are also suspected to be competitors to local aquatic plants. Tandaraporn (1962), reported the possible effect on fishes of three species of aquatic plants, namely C. caroliniana, N. indica and P. crispus in helping to prolong the survival of 0. mossambicus. Of the exotics, introduced for aquaculture, the Chinese carps are reported to have been responsible for introduction and spread of some diseases (Kanthomthurapuch 1984). Conclusions Three purposes are recognised as reason for introduction of fishes into Thailand; for consumption, for aquarium and for aquaculture (Tables 1 and 2). There are about 15 species of exotic fish that can be classified as being used in aquaculture. They have successfully survived and grow in natural waters and impoundments in Thailand. Only two species 0. mossambicus and 0. niloticus are capable of reproducing in reservoirs and in natural waters. It is also noticeable that the number of exotics of African origin has increased from 1963 to There were at least 19 species of African fishes in 1988, as compared to 6 species in The exotic species form the American continent (North, Central and South America) have also increased from 42 species in 1963 to 52 species in 1988 (Table 3).

133 122 It is also found that the exotic species for the aquarium fishes in Asia have decreased from 18 species in 1963 to only 15 species in The exotic marine fishes, mainly from the Philippines have increased from 2 species in 1963 to 5 species in 1988 (Table 3). Only a few species of the exotic aquarium fishes can breed successfully naturally in Thailand. It is also suspected that the cause of the decrease of the exotic species of aquarium fish from Asian countries might be either by the more restricted enforcement of the conservation laws or by the increasing deterioration of the natural habitats for these species in the respective countries. It is necessary for the countries in the region to cooperate in order to protect these most valuable resources. References Axelrod, H.R., W.E. Burgess, C.W. Emmens, N. Prones, J.G. Walls and R. Hunziker Atlas of freshwater aquarium fishes. H.F.H. Publication, Inc. 992p. Amatayakul, C Gold Fish. Thai Fisheries Gazette 10(2): 169. Cheunsri, C The survey of the exotic aquarium fishes in Bangkok. Senior thesis for the B.S. degree, Faculty of Esheries, Kasetsart University, 99 p. Daungsawat, S. and T. Puphipat Life history of exotic species. The Institute of the National Freshwater Fisheries, Report 7: 52p. Kanthomthurapoch P. 1984, Introducing of the life aquatic animals of Thailand. Thai Fisheries Gazette 3: Pawapootanon, A Fish stocking program in the Ubolratana Reservoir. Thai Fisheries Gazette 35(2): Tandarapom, K Use of aquatic plants for fish culture. Thai Fisheries Gazette 15(4): Tayoo (Pen name) Kob Krating: Is it a real threat then? Thai Fisheries Gazette 13: 7-8. Santi (Pen name) Aquarium Tank Plant Decoration. Thai Fisheries Gazette 13:

134 123 Table 1 a. Exotic fishes introduced to Thailand from North, Central and South America. Taxonomic Status Common Name Introduced from Year Disease Original Acestrorhnamchus hepsetes Argentina 1960 Aequidens rivulatu.s Riverlatus cichlid erun South America terro Aphyocharax robotropinis Bloodfish Argentina 1950 Apteronotus albifrons Black ghost Astronotus ocellatus Oscar, peacock eye cichlid Amazon, Paraguay White spot disease Astyanexfasciatusr albino silver tetra Central & South America Carnegiella marchae Black winged hatchet fish Orinoco, Amazon, Brazil 1957 C. strigata Marble hatchet fish Guiana, South Amazon Chiaroden axeirodi Cardinal tetra South America Cichiasoma bicellatwn Jack Dempsey Amazon C. citrinellum Red devil cichlid C. corydhaenoides Chocolate cichlid C. managuen Manguense cichlid Nicaragua, Central America 1983 C. meeki Fire mouth cichlid Yucatan C. nigrofasciatum Pink cichlid White spot disease C. severum South Texas C. cyanguttatwn Texas cichlid C. synspilum Firehead cichlid Corydoras aineu.s Bronze catfish C. haotatus Dwarf corydatus Amazon 1950 C. paleatus Peppered cory Argentina, Brazil Gambusia affinis Gymnocorymobus lerneizi Black tetra, Black Kamoor Paraguay, Argentina 1950 Gastropelacus leviz Silver hatchet fish Brazil 1956 G. sternicla common hatchet fish Venezuela Hemigrammus ocelliler head and tail light Amazon, Brazil, Guiana H. puicher Pretty tetra Amazon, Peru 1960 H. rhodostomu.s Ilyphessobryconflammesss Flame tetra, Red tetra Rio de Janeiro 1950 H. innesi Neon tetra Upper Amazon 1953 Hypostomus plecostomu.s Sucker catfish Lebistes reticulatus Guppy, Rainbowfish Trinidad, Venezuela Lepisosteu.s oculatu.s Gar pike or spotted Gar pike North America Molliensia velfera Giant Sailfin molly Yucatan Moenkhausia sahctaefilominae Moenkhausia M. digolepis Glass tetra Brazil 1957 Namnostomus aripirangensis Brown pencil fish Amazon N. anomalu.s steindachner Osteoglossum bicirrhoswn arozena Guiana, Amazon 1959 Phraetocephalus hemlliupteru.s Red tailed catfish Paecilia reticulata Guppy, million fish Poecilo brycon unifasciatus one-tailed pencilfish 1959 Poecilia latipinna Sailfish molly Mexico, Texas, Florida, Virginia Pseudoptatystomafasciatwn tiger shovelnosed catfish Amazon Pristelta riddui Pristella x-ray fish North of SA, Guiana 1950 Pterophyllwn scalar Angelfish Guiana Thaveria bochlkei T. obliques South America Tilapia buttikoferi Hornet tilapia cichlid Xiphophorus maculatus Red platy Guatemala, Honduras

135 124 Table lb. Exotic fishes introduced to Thailand from Africa, Asia and Australia. Taxonomic Status Ccinmon Name Introduced from Year Disease Original Po/ypterus deihezi Monodactylus arrgenteus and M. sebae, M.falciformis Labidochromsr exasperatus Hepsetas odoe Tetraodon miurus Hapiocronsis polystigma Distighodas sexfasgiasus Brachydania redo Amphiprionfrenatu.s Acanthurus leucosleron Et ropi us rnaculatur Barbus, sach.ri Barbus titteya Luciocephaiu,r puicher Pesudochronsis paccanella Porno centhres semicircvjasus Tanichthyzs albonubes Micralesles interrupt us Phenacogramnsus interrupt us Hap! ochrornis senustus Aulonocara nyashsa Heterosis,siloticus Scieropages fordmi Halaptearus elecirictes Platax orbics.jaria Melanochromis auras us Distichodus lusosso Hap!ochrorni.r moorii Etroplus maculalus Aulonocara nyassae Gnaihomus pet ersi Hap! ochrornis callipterus Mormyras nigricans Pee udot ropheus iropheus Delnezi's biebir Mono, Malayan Angle, Fingerfish Likoma pearl cichlid African pika characin Red Puffer, Congo puffer Polyatigma cichlid, Polly cichlid dow terra, Six-barred distichodus Zebra danio Tomato crown fish Powder blue surgeon Orange chromide cichild Gold-fmned bath, Sach's barb Cheny bath Pike-head Paccaneila Blue koran White doud, mountain minnow Congo tetra Malawi- blue African arovana Australian arovana Electric catfish Bat fish Auratus cichlid, Malawi Golden cieblid Long nosed clown tetra Blue dolphin, Blue lumphead Orange chromid cichlid Yellow Malawi, Malawi Gold Elephant nose Callipterus cichlid Mormyrid Tropheops cichlid, Black dorsal fin Middle of Congo river, Africa East Africa, Malaysia. Borneo Common in Malawi, Lake Tanganyika, Africa Central Africa Africa, Congo River Africa, Congo river Western India Phillipines Indo-pacific to Red Sea. Sri Lanka and part of India Singapore. Malaysia Sri Lanka. Asia Malaysia, Sumatra, Sends Islands, Borneo Indonesia Phillipines China Zaire, Africa Victoria Lake Malawi Lake River Nile, Africa New Guinea Central Africa Philhipines Malswi Lake, Africa Congo river, Africa Sri Lanka, India, Asia Sri Lanka, India, Asia Malawi Lake, Africa Central Africa Malawi Lake, Africa Africa Malawi Lake, Africa Note: Marine Note: M:arine Note: Marine Note: Marine Note: Marine Note: Marine Note: Marine Table 2. Live fish species which were introduced to Thailand for aquaculture and for scientific research. Scientific Name Introduced From Oreochrorner,nossarnbi cur 1949 Malaysia T. melanopleura 1955 Belgium O.rsi!oticus 1965 Japan 0. aareue 1970 Israel Cyprissuscarpio 1912 China Hypophthalmichthys molitrix 1932 China Cienopharyngodon (della 1932 China Ari.rtichthys nobilis 1932 China Labeo rohita 1968 India Cotta cotla 1979 Bangladesh Caraxrirsr caro.ssius 1980 Japan Cirrhin,sa inrigala 1980 Japan Angaillafaponica 1973 Japan Salmo gairdneri 1973 Canada Onchorhyncris rlrodorus 1981 Japan Table 3. Comparison of the exotic species for aquarium fishes in 1963 and Origin Asia 18 Species 15 Species Africa 6 Species 19 Species Australia I Species 1 Species America North, Central & South 42 Species 52 Species Marine 2 Speciea 5 Species Total 69 Species 92 Species (Source: Daungsawat and Phupipat 1982)

136 Australian Government Position: Introduction of Exotic Aquatic Species FRANCES B. MICHAELIS Australian National Parks and Wildlife Service GPO Box 636 Canberra, ACT 2601 Michaelis, F.B Australian government position: introduction of exotic aquatic species, p In S.S. De Silva (ed.) Exotic Aquatic Organisms in Asia. Proceedings of the Workshop on Introduction of Exotic Aquatic Organisms in Asia. Asian Fish. Soc. Spec. Pub!. 3, 154 p. Asian Fisheries Society, Manila, Philippines. The impact of introduced aquatic species on native species in Australia is considered. In addition the role of the Commonwealth Government and other statutory agencies in the protection of the Australian native flora and fauna is discussed. The mechanisms that regulate importation of live animals and plants into Australia are briefly presented. Australian obligations enacting international conventions for the protection of flora and fauna, and future directions in conservation are dealt with. In Australia the impact of introduced aquatic species on native species and their habitats has been considerable. About 22 species of freshwater fish, numerous aquatic invertebrates and 15 species of undesirable aquatic weeds have been mtroduced. There is an awareness of the need for State and Commonwealth legislation to protect native aquatic species and their habitats within Australia. The most important Commonwealth legislation to protect aquatic fauna is the Wildlife Protection (Regulation of Exports and imports) Act, 1982 which protects endangered wildlife and wildlife that would be threatened by continued unregulated trade. The Act seeks to prevent the introduction of live plants and animals that could adversely affect the Australian natural environment. The Act is administered by ANPWS, with technical advice in aquatic matters from the Advisory Committee on Live Fish (ACOLF) of the Australian Fisheries Council. At present, a few hundred species are permitted imports under Schedule 4 (freshwater fish) and Schedule 6 (marine aquarium fish). The Convention of Conservation of Nature in the South Pacific (Apia Convention) and the Convention for the Protection of the Natural Resources and Environment of the South Pacific (SPREP Convention ) are outlined to p"vide models that might be considered by the Asian nations for regional co-operation in environmental conservation. In Australia, the impact of introduced aquatic species on native species and their habitats has been considerable. The following have been introduced: about 22 species of freshwater fish (McKay, present volume) eight marine and estuarine (including anadromous) fish (Pollard and Hutchings, pers. comm.) numerous aquatic invertebrates 15 species of undesirable aquatic weeds (Arthington and Mitchell 1986) and at least eight species of marine algae (Pollard and Hutchings, pers. comm.). There is an awareness of the need for State and Commonwealth legislation to protect native aquatic species and their habitats in Australia. The present paper addresses ways in which Commonwealth Legislation protects native aquatic species. 125

137 126 The Role of the Commonwealth Government In Australia, responsibility for management of native fauna is vested with each State and Territory Government. The Commonwealth (Federal) Government has responsibilities for fauna in Commonwealth Territories, as well as for matters relating to fauna in import and export control, foreign affairs and foreign trade. Responsibility for fisheries management rests with the State and Territory Governments except for the above mentioned matters. In 1976, the Endangered Species Regulations were promulgated under the Customs Act This legislation remained in force until 1 May 1984 when the Wildlife Protection (Regulation of Exports and Imports) Act 1982 came into effect. In the matter of import and export control of fish (excluding fish products'), the most important Commonwealth legislation is the Wildlife Protection (Regulation of Exports and Imports) Act This Act protects endangered wildlife and wildlife that would be threatened by continuation of unregulated trade (Schedules 1 and 2), generally precludes export of live Australian fauna for commercial purposes, and seeks to prevent introduction of live plants and animals that could adversely affect the Australian natural environment (Schedules 5 and 6). Schedule 6 contains a listing of aquarium fish, both freshwater and marire that are 'permitted imports'. Schedules to the Act are regularly amended. With the commencement of the Act, all previous controls were consolidated into a single piece of legislation and responsibility for administration was placed with the Australian National Parks and Wildlife Service (ANPWS). Under the Act, the export and import of wildlife (and wildlife products) which is threatened with extinction or considered endangered is strictly regulated. Permits for trade in such wildlife are provided where certain conditions prevail, and the trade is for scientific or bona fide zoological purposes, or the wildlife has been bred in captivity or artificially propagated. Importation of species, such as aquarium fish, which could threaten the survival of wildlife within Australia is also subject to control. Intending importers should write to the Director, ANPWS, GPO Box 636, Canberra, ACT 2601 Australia and complete a proforma outlining distribution, ecology and potential of the species to establish feral populations. All applications are considered by the Advisory Committee on Live Fish (ACOLF) to the Standing Committee of the Australian Fisheries Council. This technical advisory committee includes Commonwealth Government (ANPWS, Australian Quarantine Inspection Service (AQIS)), State and Territory Fisheries Authorities (8 members), an expert on fish disease and an expert on aquarium fish and meets twice a year. Criteria used by ACOLF in assessing applications are attached (Appendix III); the emphasis being on the potential of the species to survive and disperse in the wild. The export of Australian wildlife requires a permit unless exempted by the Act. Export of live Australian animals is only permitted for scientific or bona fide zoological purposes, or as household pets, in which case there are stringent requirements which must be met. The Role of ANPWS in Administration ANPWS has, since proclamation of the Wildlife Protection Act, been endeavouring to strengthen and develop close liaison with all Australian Conservation agencies and with all Federal departments which have a relationship to the control of wildlife.

138 There are presently eight State or Territory Wildlife agencies in Australia. Each operates independently and exercises control and enforcement of wildlife matters under separate pieces of legislation. Such legislation regulate the trade, holding of, and movement of wildlife both within and between Australian States and Territories. Law enforcement is conducted at the State and Territory level by officers of each conservation Service and is supported by Statelferritory police forces. Such legislation is not considered further in this paper. The international movement of fauna and flora is a Federal responsibility and, dependent upon the commodity, is administered by a variety of departments, e.g., with regard to fish: Trade in fish products - Australian Fisheries Service, Department of Primary Industries and Energy; Import and Export of fish - Australian National Parks and Wildlife Service, Australian Quarantine and Inspection Service (AQIS). At the Federal level, enforcement is primarily the responsibility of the Australian Federal Police and the Australian Customs Service. In September 1985, ANPWS hosted the first national seminar on wildlife law enforcement, which was conducted in Canberra. The seminar was designed to encourage wide-ranging discussions on enforcement matters (regardless of State or Federal requirements). Similar seminars have been held in Canberra, October 1986 and in Adelaide, April 1988, on the theme of intelligence gathering. As a result of the above seminars, a number of prosecutions were initiated at both the State and Federal level. ANPWS has been dealing with a number of Convention on International Trade in Endangered Species (CITES) countries particularly USA, West Germany, South Africa and Denmark, on enforcement matters. 127 The Role of ANPWS in Research The aim of the ANPWS Research and Survey Program is to facilitate the production of reliable scientific and socio-economic information for the formulation and implementation of nature conservation policies and management programs. Priority information needs are periodically reviewed and the scope of the program is revised accordingly. The Research and Survey Program comprises a suite of projects funded on the basis of contracted consultancy services. Projects on exotic fish are listed at Appendix I and the full titles of the Reports are given in the references. A recent survey of the introduced Tilapia, in the Cairns region of North Queensland (Lear 1987) suggested that they have set up populations up to 3 km from point of release over a period of 5 years, and will eventually become common in wetlands in the Cairns city area. The means of dispersal, whether by nature or man, could not be determined.

139 128 The International Obligations of Australia The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is probably the most important international agreement protecting endangered species of plants and animals. The governments of ninety three countries, including Australia, have now signed CITES. Through CITES, these countries are trying to establish a worldwide network of controls on trade in endangered species and species that could become endangered. Within the member countries of CITES, Australia stands to the fore in providing protection of its native animals and plants, in particular those that are endangered. The Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention) aims to promote the conservation of wetlands and waterfowl, to establish nature reserves on wetlands and provide adequately for their protection and wardening and to promote training of personnel competent in the fields of wetlands research, management and wardening. In addition, it aims to increase, through management, waterfowl populations on appropriate wetlands. Australia signed the Convention without reservation as to ratification in 1974 and became the first country to do so. The agreement came into force internationally on 21 December Regulations to implement this Convention in Australia were not needed since the Convention imposes responsibilities which may be met either administratively or by action under existing legislation. A Working Group of the Council of Nature Conservation Ministers (CONCC)M) has been established to advise on the implementation of the Ramsar Convention. CONCC)M has agreed that the nomination of wetlands to the List of Wetlands of International Importance is the responsibility of the individual States and the Northern Territory. The Australian National Parks and Wildlife Service, which is the principal advisor to the Commonwealth Government on national nature conservation and wildlife policies, provides the Convenor for the Working Group and co-ordinates activities under the Convention, including submission of nominations for wetlands to be added to the list (Appendix II) and the preparation of the national reports. There are two international conventions in which Australia has an interest that serve as models for regional co-operation in environmental conservation. Although there are some important differences, the two can be seen as complimentary. The Convention on Conservation of Nature in the South PacWc (Apia Convention) was adopted in 1976 but has not yet entered into force. Australia intends to accede to the Convention, which aims to take action for the conservation, utilization and development of the natural resources of the South Pacific Region. Article V, paragraph 4 states "Each contracting party shall carefully consider the consequences of the deliberate introduction into ecosystems of species which have not previously occurred therein". The Convention for the Protection of the Natural Resources and Environment of the South Pacific Region (SPREP Convention) is not yet in force. Australlia signed the Convention in 1987 but has not yet ratified it. Article 14 is concerned with Specifically Protected Areas and the Protection of Wild Flora and Fauna. It aims to "preserve depleted, threatened or endangered flora and fauna... prohibit or

140 regulate any activity likely to have adverse affects on the species, ecosystems or biological processes that such (protected) areas are designed to protect". 129 Possible Future Directions Future directions may involve new legislation, a threatened species initiative and further education. The new legislation would be helpful if it provided uniformity between States, Territories and the Commonwealth to define fish species that may be imported, translocated, released, etc. Commonwealth Government activities already protect threatened species and their habitats by the provision of research funds, provision of funds to States for purchase of property, management of threatened species in areas under Commonwealth control, and the implementation of obligations under international treaties. The Commonwealth Government has established an Endangered Species Advisory Committee to advise the Minister for the Arts, Sport, the Environment, Tourism and Territories on strategies, priorities and implementation of the endangered species program. The Government is also moving to create within the Australian National Parks and Wildlife Service (ANPWS) an Endangered Species Unit which will establish programs for conservation of endangered wildlife in co-operation with State agencies. There is an urgent need for programs to inform the public about native aquatic invertebrates and fish, and to make people aware of the dangers of exotic fish and invertebrate introductions. Relevant Literature Anon Convention on Conservation of Nature in the South Pacific. Apia, 12 June Anon Wildlife protection (Regulation of Exports and Imports) Act Australian Government Publishing Service. No. 149 of Arthington, A.H. and D. Milton Ecology and interaction of exotic and endemic freshwater fishes in South Eastern Queensland streams. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra, Australia. 403 p. Arthington, A.H. and D. Mitchell Aquatic Invading Species, p In R.H. Groves and JJ. Burdon (eds.) Ecology of Biological Invasions: An Australian Perspective. Australian Academy of Science, Canberra. Lear, R.J Survey of introduced Tilapia in the Cairns Region, North Queensland. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra. Australia. XX p. McKay, RJ The Exotic freshwater fishes of Queensland. Consultancy Report prepared for Australian National Parks and Wildlife Service, Canberra, Australia. 103 p. McKay, R.J. Present volume. Michaelis, F.B Threatened Fish. Report on threatened fish in inland waters in Australia. Australian National Parks and Wildlife Service. Report No. 3: 45 p. Michaelis, F.B Conservation of Australian aquatic fauna, p In P. De Deckker, and W.D. Williams (eds.). Limnology in Australia. CSIRO Australia, Melbourne and Dr. W. Junk Publishers, Dordrecht. Mitchell, D.S Aquatic macrophytes and man, p In P. De Deckker and W.D. Williams (eds.). Limnology in Australia. CSIRO Australia, Melbourne and Dr. W. Junk Publishers, Dordrecht. UNEP Convention for the Protection of the Natural Resources and Environment of the South Pacific Region, Regional Seas, UNEP.

141 130 APPENDIX I Australian National Parks and Wildlife Service Research and Surveys Program Exotic Fish Year Project Investigator A survey of alien freshwater fish in the Moreton Bay Region A survey of alien freshwater fish in Queensland coastal streams Mr. R.J. McKay, Queensland Museum Mr. R.J. McKay, Queensland Museum 1980/81 Ecology and interaction of Exotic Dr. A. Arthington, 1982/83 and Endemic Freshwater fishes in Griffith University South-eastern Queensland streams 1984/85 Marine Aquarium Fish - permitted imports for aquarium purposes 1986/87 Investigation of Spread of Tilapia Sarotherodon spp. in Cairns! Townsville Region Ms P. Kailola, Adelaide Mr. R. Lear, Cairns, Queensland APPENDIX II Wetlands Designated by Australia to the List of Wetlands of International Importance Name State or Location Area (ha) Territory Cobourg Peninsula, N.T 'S, 191,660 Aboriginal Land and ' - Wildlife Sanctuary 'E Kakadu National N.T ' - 667,000 Park, Stage I 'S, ' - l33000'e Moulting Lagoon Tas 'S, l48 lo'e 3,930 Logan Lagoon Tas 'S, 2,320 Conservation Area 1480 l7'e Sea Elephant Tas 'S, 1,730 Conservation Area l44 05'E Pittwater - Tas 'S, 2,920 Orielton Lagoon l47 30'E Apsley Marshes Tas 'S, 940 l48 12'E East Coast Cape Tag ' - 4,230 Barren Island 40026'S, Lagoons ' 'E Flood Plain Lower Tas 'S, 1,650 Ringaroorna River 'E Jocks Lagoon Tas 'S, 'E Northwestern Tas 'S, 270 Corner of Lake Crescent l47 l0'e Little Waterhouse Tag 'S, 90 Lake 'E Corner Inlet Vic ' 51, 'S, ' 'E Continued

142 Appendix II. Continued 131 Name State or Location Area (ha) Tethtory Barmah Forest, Vic ' - 28, 'S, ' 'E Gunbower Forest Vic ' - 19, 'S, ' - I 44 30'E Hattah-Kulkyne Vic ' - 1,018 Lakes 34045'5, ' 'E Kerang Wetlands Vic ' - 9, 'S, ' 'E Port Phillip Bay Vic ' - 7,000 (Western Shoreline) and Bellarine Peninsula 38015'S, ' 'E Western Port Vic ' - 52, 'S, ' 'E Western District Vic ' - 30,182 Lakes 38020'S, ' 'E Gippsland Lakes Vic ' - 43, 'S, ' 'E Lake Albacutya Vie 'S, 'E 10,700 Towra Point Nature NSW 34000'S, 281 Reserve 'E Kooragang Nature NSW 32051'S, 2,206 Reserve 'E Coorong and Lakes SA 35018' - 140,500 Alexandrina and Albert 36033'S, ' 'E Boo! and Hacks SA 37006' - 3,200 Lagoons 31010'S, ' 'E Macquarie Marshes NSW 30045'S, 18,200 Nature Reserve 'E Coongie Lakes SA 28 36' - 1,980, 'S, ' 'E 'Riverland SA 3401!' - 30, 'S, ' -!41000'E Total Area 3,304,690

143 132 APPENDIX LII Criteria for Permitted Importation of Aquarium Fish ADVISORY COMMITTEE ON LIVE FISH (ACOLF) to the Standing Committee of the Australian Fisheries Council Evaluation of fish species for exclusion from the list of permitted aquarium fish imposts should take into consideration the following points: Any histosy of forming feral populations elsewhere or of having caused a significant problem elsewhere. The capacity for survival and dispersal within Australia, particularly in combination with other undesirable characteristics. Any likelihood of having a significant detrimental impact on other fish species or wildlife, or on the aquatic environment. The status of the species as a known carrier of a dtsease not yet found in Australia, The ability of the species to cause injury to man, livestock, wildlife or the environment (e.g., possessing spines, electric organs, toxins). The potential for growth to a large size, particularly in species likely to be attractive under Australian conditions for aquaculture, sportfish stocking, weed control or similar activities not connected with the aquarium hobby. The degree of difficulty in distinguishing the species from other (undesirable) species. ("Look-alikes"). In addition, for marine aquarium fish, the ability of the'species to establish in estuaries or migrate into freshwaters. The availability of reliable biological information.

144 Recommendations of the Workshop 1.0 TERMINOLOGY: 1.1 It was apparent that the terminology needed careful consideration, in spite of the issue of exotics and or introductions having been dealt with from time to time. The matter was more complicated in the region because zoogeographical boundaries and country boundaries in most cases were very different from one another. 1.2 A separate sub-committee was appointed to examine and report on suitable definitions for an exotic introduction, transplant and introduction. The committee could not come-up with acceptable definitions during the workshop and the workshop requested Dr. Chua Thia-Eng and Mr. Jay Maclean to survey the available literature and submit suitable definitions for consideration by the Committee on Exotics. 2.0 DATA BASE: 2.1 A considerable amount of fresh data was presented on the introduction of exotics into the region at the meeting. Some of the information however, needed to be revised by participants and the Chairman of the Exotics Group (Dr. S.S. De S) will coordinate this activity and standardize the presentation of the data. 2.2 The Chairman will also attempt to obtain comparable data from those countries which were not represented at the Workshop, and if possible also make attempts to dig into the "grey literature" to find the same. In order to achieve this end it might be necessary to identify and liaise with scientists who are interested in the topic in each of the countries in the region. 2.3 The Workshop took into account the interests and experience of the FAQ, EIFAC and the American Fisheries Society on this topic and the need for the Society to liaise with these organizations was noted. 3.0 NEW INTRODUCTIONS: 3.1 The information available on the procedures adopted in making or deciding upon an introduction was scanty, except perhaps in Australia. Japan for example has no restrictions on live aquatic introductions. 3.2 As such, it was deemed appropriate and relevant to document the information available with respect to each country. The delegates were requested to furnish this information, in a schematic form, in due course. The Committee on Exotics will attempt to compile this information in a publishable form. 133

145 AQUARIUM FISH: 4.1 The delegates expressed concern over the growing aquarium fish trade which in most instances is responsible for introduction and spread of diseases. 4.2 The meeting agreed that an attempt should be made to list the common aquarium fish species imported/exported into from each country in the region, with notes on the quarantine measures adopted. All delegates were of the view that this is a very difficult task to achieve and would take a considerable amount of time to prepare an accurate list. 4.3 Instances in which a fish such as pirranha imported for the aquarium industry in Thailand has been discovered in the natural waters, were cited as examples of the need to address the issue in greater depth. 5.0 IMPACT OF INTRODUCTIONS: 5.1 It was agreed that most introductions, especially the food fish species, have had considerable socio-economic impact in most countries, in the region. It was also recognized that unlike in Europe, North America or for that matter, Australia, the assessment of the impact in most Asian countries should be made from. a different view point. As an initial step, five criteria were agreed upon to dei:ermine the impact of introduced, common food fish species, such as for example i;he tilapias, carps, etc. into each of the countries. The final assessment is to be published in the Proceedings of this Workshop. 5.2 It was also felt that Asia has suffered few losses of native species upi:o now and the number endangered are also small as a result of introductions. However, this was no matter for complacency and the need to scrutinize the new proposals for introductions was accepted. 6.0 FUTURE ACTION: 6.1 It was agreed that the results of this Workshop should be published as an Asian Fisheries Society Publication. The publication would include the revised, presented papers and further data which the participants were asked to furnish and summary tables on a regional basis. 6.2 A standing committee of the Society on 'Exotics' consisting of Prof. Sena S. De Silva Dr. Frances Michaelis Dr. M. Shariff (Chairman) (Australia) (Malaysia)

146 (two more to be co-opted) was appointed. This Committee will liaise with other organizations and countries, explore ways of addressing the issue of exotics in depth, and collect and synthesize data on exotics to provide relevant and useful information to Governments in the region when and if needed. 135

147 List of Participants Dr. Angela H. Arthington, Division of Australian Environmental Studies, Griffith University, Nathan, Queensland 4111, AUSTRALIA Mr. Don Buckmaster, Fisheries Division, Department of Conservation Forests and Land, Arthur Rylan Institute, 123, Brown Street, Heiderberg, Victoria 3084, AUSTRALIA Dr. Kenji Chiba, Fisheries Lab, The University of Tokyo, Maisak, Hamana, Shizuaka, JAPAN Dr. F. Brian Davy, IDRC, Tanglin P.O. Box 101, SINGAPORE 9124 Prof. Sena S. De Silva, Department of Fisheries Biology, University of Ruhuna, Matara, SRI LANKA Dr. Chua Thia-Eng, do ICLARM, MC P0 Box 1501, Makati, Metro Manila, PHILIPPINES Dr. H. Muhammad Eidman, Faculty of Fisheries, Bogor Agricultural University, Darmaga Campus, Bogor, INDONESIA Mr. Darryl Grey, Department of Industries and Development, GPO Box 4160, Darwin NT 5794, AUSTRALIA Dr. John D. Humphrey, Australian Fish Health Reference Laboratory, P0 Box 388, Bendila, Victoria 3672, AUSTRALIA Dr. Rogelio 0. Juliano, University of the Phillipines in the Visayas, Iloilo City, PHILIPPINES Dr. Akio Kanazawa, Faculty of Fisheries, Kagoshima University., Shimoarata, Kagoshima, JAPAN Ms. Henen K. Lasson, Northern Territory Museum, P.O. Box 4646, Darwin, N.T. 5794, AUSTRALIA Dr. I. Chiu Liao, Taiwan Fisheries Research Institute, 199 Hou - Ih Rd. Keelung, TAIWAN Dr. Hsi-Chuang Liu, Institute of Oceanography, College of Science, National Taiwan University, Taipei, TAIWAN 136

148 137 Mr. J. Maclean, do ICLARM, MC P0 Box 1501, Makati, Metro Manila, PHIILIPPINES Dr. Frances Michaelis, ANPWS, GPO Box 636, Canberra, Act 2601, AUSTRALIA Mr. Michael Peani, cl- Department of Industries and Development, GPO Box 4160, Darwin, N.T. 5794, AUSTRALIA Dr. Twesukdi Piyakarncha, Dept. of Marine Science, Faculty of Science, Chulalongkorn University, Bangkok 10500, THAILAND Prof. Meng Quing-Wen, Shanghai Fisheries University, 334, Jun Gong Road, Shanghai, CHTNA Dr. David Ramm, Fisheries Division, Dept. of Industries and Development, GPO Box 4160, Darwin, N.T. 5794, AUSTRALIA Prof. H.P.C. Shetty, Director of Instruction (Fisheries), University of Agricultural Sciences, College of Fisheries, Mangalore , INDIA

149 138 APPENDICES On the basis of the specific recommendation made by the Workshops attempts were made to gather additional information regarding introductions made in those Asian countries that were not represented,compile a list of aquarium fish introduced into each country, and assess the impact of major food fish species introductions. Needless to say that all the objectives set out could not be fully realized at the time the Proceeding went for print. Contacts were made with scientists in Bangladesh, Burma, Cambodia, Laos, Nepal and Vietnam amongst others; not all of them however, have responded. In spite of these limitations some of the information is included as it is hoped that this will provide the base for a more comprehensive documentation at a later date. The appendices that follow are therefore, not strictly a part of the Proceedings but are components of the follow-up activities adopted by the Workshop.

150 Appendix I Definitions of Exotics The 1986 ASFA Thesaurus gives a "scope note" or "rough definition" of introduced species as "Establishment in a new geographical area of a species by migration or artificial transportation." The same Thesaurus gives a "rough definition" of transplantation as "Artificial" introduction of organisms into habitats where they do not occur naturally. The ASFA Thesaurus does not use the word exotic. Welcomme, R.L (International introductions of inland aquatic species. FAO Tech. Pap. 294, 318 p.) follows the 1987 EIFAC Code of Practice, which used these definitions. Introduced species (includes both non-indigenous and exotic species): Any species intentionally or accidentally transported and released by man into an environment outside its present range. Transferred species (includes transplanted species): Any species intentionally or accidentally transported and released within its present range. "Transfers are usually intended to support stressed populations, introduce genetic diversity into a stock or to reestablish a species whose stocks have failed locally. Introductions are intended to insert a totally new element into the fauna". Welcomme commented, "One reservation is made with respect to these definitions in that a species is considered to have been introduced to a country once it has crossed national boundaries. This means that species are included in the listing if they are transported into a country as part of current commercial practice for food or ornament and not for stocking into natural environments. Experience has shown that even such species may have impacts through the release of pathogens or through escape." Marine species: Any aquatic species that does not spend its entire life cycle in fresh water. Introduced species (= non-indigenous species; includes both non-indigenous and exotic species): Any species intentionally or accidentally transported and released by man into an environment outside its present range. Transferred species (= transplanted species): Any species intentionally or accidentally transported and released within its present range. Quarantined species: Any species held in a confined or enclosed system that is designed to prevent any possibility of the release of the species, or any of its diseases or any other associated organisms into the environment. 139

151 140 In the article "Strategies for reducing risk from introductions of aquatic organisms" by C.C. Kohler (Fisheries 11(2): 2-3 (1986)), the definitions used, which were those of Shafland, P.L. and W.M. Lewis 1984 (Terminology associated with introduced organisms. Fisheries 9(4): 17-18), were explained thus: For the present purposes, the terminology associated with introduced organisms follows that of Shafland and Lewis (1984). They define introduced as a plant or animal moved from one place to another by man (i.e., an individual, group, or population cr organisms that occur in a particular locale due to man's actions). They define exotic as an organism introduced from a foreign country (i.e., one whose entire range is outside the country where found), and a transplant as an organism moved outside its native range but within a country where it occurs naturally (i.e., one whose native range includes at least a portion of the country where found). The above terminology was adopted by the AFS Exotic (Introduced) Fish Section, but not without some debate. There is some disagreement with respect to the "fish nationality" context inherent within the terminology. Some scientists argue that since fish can't possibly recognize national boundaries that the inclusion of "nationality" in terminology should be avoided. On the other hand, man does recognize national boundaries, and since a fishery is defined as a system composed of habitat, biota and man (Lackey 1974), the "nationality" usage would seem to have validity. The term introduction implies man's involvement (Kohier and Stanley 1984), and therefore should not be confused with natural migratory or invasionary movements. Fortunately, the definition quandary can be effectively resolved by referring to "introduced species" (exotics and transplants) when dealing with the topic in an ecological context, and incorporating the "political" terminology when addressing the international concerns.

152 Appendix II Assessment of the Impact of Major Food Fish Species Introduced into Some of the Asian Countries The Workshop decided upon five criteria, admittedly not all of them easily evaluable nor objective, as the most appropriate means of assessing the success of the major food fish species introductions on the information available presently. The five criteria are as follows: the introduced species is self-reproducing in natural waters and/or easily bred under hatchery conditions in the host country, the introduced species has resulted in an increase in production, the introduced species has not been responsible for transmission and/or introduction of a new disease, the introduced species has not endangered any of the indigenous fish species, and the introduced species has not had any detrimental/deleterious effects on any waters. On this basis a total of 58 species belonging to 15 families which are considered as food fish by each country were assessed, and the details are given in Tables All In certain instances a species considered as a food fish by one country may not be given a similar status by another. For example, Oreochromis mossambicus is not treated as a food fish in Australia and in Singapore. If a species has been introduced to all countries in Asia under review and is treated as a food fish by all, a total maximum score of 45 is possible. In this manner, the actual score for each species as a percentage of the maximum attainable was calculated (Table AII.1O). From the data presented it is therefore, evident that very few species have had an overall detrimental influence on the native flora and fauna. Also it should be borne in mind that in certain countries because of the prevailing socio-economic conditions and cultural preferences a species may be considered as a 'nuisance' or having a degradatory effect on the native fauna. A case in point is the role of 0. mossambicus in Indian waters; it is conceded there had been an increase in production, at least in some waters due to this species, and there is no firm evidence to show that it has brought about a decline in production or elimination of native species. In spite of these, the species is categorized as a 'nuisance' species. A similar trend of thought to be now developing with respect to Chinese bighead carp. Admittedly, it is difficult to remove these biases entirely, especially when the criteria of assessment of the success of a species are not fully objective. It is important for the readers to be aware of these apparent biases. It is also evident from the assessment tables of individual countries that few food fish introductions are associated with introduction of parasites and diseases. Most food fish introductions were made in the 1950's to late 1960's. It may be because a knowledge of 141

153 142 fish diseases was not well developed during this period and that some of the accidental introductions of parasites and diseases may have gone unnoticed or not attributed to the introduced species. Table All. 1. Assessment of the status of food fish species introduced into Australia. Species Criteria SALMONTDAE Salmo gairdneri + + Salmo trutta Salvelinusfontinalis + + CYPRINIDAE Tinca tinca Rutilusrsuilus PERCICHTHYIDAE Percafluviatilir The Atlantic salmon, Salmo salar, forms the basis of a developing fisheiy, but salmon are confined at present to cages in the sea. Table AU.2. Assessment of the status of food fish species introduced into India. Species 1 2 Criteria 3 4 5, CYPRINIDAE Carassiuscarassius Cyprinss carpio var. communis Cyprinuc carpio var. specularis Cienopharyngodon idella Hypophthalmichthys molitrix Puntiusjavanicus CICHUDAE Oreochromis mossambicus + + OSPI-IRONEMTDAE Osphronemus goramy SALMONIDAE Salmogairdneri S.truttafacio

154 143 Table All.3. Assessment of the status of food fish species introduction into Japan (only those species which satisfied at least one of the five criteria are included). Taxonomic status Criteria SALMONIDAE Salmo gairdneri + trulia O.kisutch + Sal velinus namaycush + S.fontinals Coregoniss lava ret us maraena + CYPRINIDAE Aristichthys nobilis Hypophthalinichthys molitrix Mylopharyngodon piceus + - Rhodeus ocellatus ocellatus Cyprinus carpio ruscus - - Cyprinuscarpio* Megalobrama amblycephala + - Tinca tinca + - KTALURJDAE Ictaluriss punctatus + ATHERINTDAE Odonthestes bonariensis + CENTRARCHTDAE Lepomis,nacrochirus + + Micropterus salmoides CICI-ILTDAE Oreochromis aureus ,nossambicus urolepis hornorum + - (reported as Tilapia macrocephala) 0. niloticus Tilapia spa rrmanii zulu BELONTIIDAE Macropodus chinensis + + CHANNTDAE Channa argus + C.maculata + +

155 144 Table All.4. Assessment of the status of food fish species introduction into Malaysia. Family/species Criteria CICHLIDAE Oreochromis mossambicus O.nilolicus CYPRJMDAE Cyprinuscarpio Cienopharyngodon idella Aristichthys nobilis Hypophihalmichihys nwlitrix Labeo rohita OSPFIRONEMIDAE Trichogaster pectoral is Table AILS. Assessment of the status of food fish species introduction into the People's Republic of China. Family/species CENTRARCHIDAE Micropterus sairnoides Procambarus clarkii CHARACIDAE Colossotna bidens Criteria CICHLIDAE Oreochromis,nossambicus + - O.niloticus O.aureus Sarotherodon galilaeus T. zillii CLARUDAE Clarias batrachus C. macrocephalus C.lazera CYPRINIDAE Carassius auratu.s cuvieri Puntius gonionotus + + Catla catla Labeo rohita Cyprinuscarpio (Scattered mirror carp) ICTALURIIDAE Ictalurus punctalus I. nebulosict PANGASIDAE Pangasius sutchi SALMONIDAE Salmogairdneri Coregornispeled Coregonus sp

156 145 Table All.6. Assessment table of the statue of food fish species introduced into the Philippines. Species ANBANTIDAE Helostoma lem,nincki Criteria (no information) CENTRARCHIDAE Microplerus salmoides Lepoms macrochirtss L. cyanellus CICHLIDAE Oreochromis mossambicu.s 0. niloticus 0. aureus T. zulu CLARIIDAE Clarias batrachus Clarias lazera CYPRIMDAE Cyprinus carpio Ctenopharyngodon idella Aristichthys nobilis Hypophihalmichihys molitrix Labeo rohila Catla catla Carassius carassiu.s Cirrhinus molitorella C. mrigal Puntiusjavanicus Osteochilus hasselli ICTALURIDAE Ictalurus catus I. punctatus OSPHRONEMIDAE Trichogaster pectoralis T. trichoplerus T. leeri Osphronemus goramy (No information available) (No information available) (No information available) (No information available) (No information available) (No information available) (No information available) (No known population) (No known population) (No information) (Only those species that have had some impact on fish production is considered).

157 146 Table A117. Assessment of the status of food fish species introduction into Sn Lanka. Species 1 2 Criteria CYPRThTDAE Aristichihys nobilis Catlacatla Cirrhinus mn gal + Crenopharyngodon idella Cyprinus carpio Hypophihalmichihys molitrix Labeo rohita CICHLIDAE Oreochroms mossambicus niloticus Tilapia rendalli Tilapia zulu OSPFIRONEMIDAE Osphronemus goramy + + SALMONTDAE Salmogairdneni S.truita + + +

158 Table All.8. Assessment table of the status of food fish species introduced into Taiwan. 147 Species Criteria FINFISH ANGUILUDAE Anguilla anguilla CENTRARCHIDAE Microplerus salmoides CHARALIDAE Colossoma bidens Sciaenops ocellatus CICHUDAE Oreochromis mossambicus O.aureus O.hornorum nilolicus Oreochromis sp. (red tilapia) T. rendalli CLARIIDAE Clarias balrachu.s CYPRIITDAE Arislichihys nobilis Carassius auralus Cirrhina,noliiorella Clenopharyngodon idellus Cyprinuscarpio Hypophlhalmichrhys molitrix Leprobarbus hoevenii Megalobrama amblycephala Mylop/taryngodon piceus ICTALURTDAE Ictalurus punclatus PANGASIDAE Pangasius cute/ti SALMONIDAE Salmo gairdneri Table All.9. Assessment table of the status of major food fish species introduced into Thailand. Species Criteria CICHLIDAE Oreochromis mossambicus O.aureus niloticus T. rendalli CYPRINTDAE Aristichthys nobilis + - Catla caila Cirrhina mrigala Clenopharyngodon idellus Cyprinuscarpio Hypophthalmichthys molitrls Labeo rohita + +

159 Table All. 10. The summaiy score of each food fish species in the host countries (mdi. - India; Malay. - Malaya; PRC - People's Republic of China; SL - Sri Lanka; Taiw. - Taiwan; Thai. - Thailand) and the potential total score (PTS), the total score ('1'S) and the total score as a percentage of PTS (%). (+) - introduced but no information available and were not taken into the score analysis. Family/Species Countries introduced into Score analysis Aust. mdi. Jap. Malay. PRC Philip. SL Taiw. Thai. PTS TS ANABANTJDAE Helostoma temminicki + ANGUILLIDAE Anguilla anguilla ATHERINIDAE Odonthestes bonariensis BELONIIDAE Macropodus chinensis CENTRARCHTDAE Lepomis,nacrochirus L. cyanellus + Micropterus salmoides Procambarus clarkii CHANNIDAE Channa argsts C. maculata CHARACIDAE Colossoma bidens CICHLIDAE Oreochromisaureus O.hornorwn O.mossambicus niloticus Sarotherodon galilaeus Tilapia rendalli T. sparrmanii T. zulu CLARI[DAE Clarias batrachus C.lazera C. crccepha!us go CYPRINIDAE Aristichihys nobilis Carassiusauratus (varieties) C. carassius Catla cotta Continued

160 Table All.10. Continued Family/Species Countries introduced into Score analysis Aust. mdi. Jap. Malay. PRC Philip. SL Taiw. Thai. PTS TS % Cirrhinus pnolitorella Cirrhinus mrigal Ctenopharyngodon idella Cyprinus carpio Hypophzhalmichthys molirrix Labeo rohia Leptobarbus hovenii Megalobrama amblycephala My! opharyngodon picejis Osteochilu hasselti + Puntius gonionotus P. javanicus Rhode us ocellatus ocellatus Rutilus rutilus Tinca tinca ICTALURIDAE Ictaluruspunctatus Lcatus I. nebulosus OSPRRONEMIDAE Osphronemus gouramy Trichogaster pecloralis T. leeri + T. Irichopterus PANGASIDAE Pangasius sutchi PERCICHTHIDAE Percafluviasilis SALMONIDAE Coregonus peled C.sp C. lavaretus maraena Onchorhynchus kisutch Salmogairdneri S. trutta Salvelinusfontinalis S. namaycush

161 Appendix III Instances of Decline/Disappearance of Indigenous Species as a Possible Consequence of Introduced Fish Species It will be apparent from the individual presentations that the number of instances, in the area under review, that an indigenous species was made extinct or endangered as a consequence of an introduction were few. Nevertheless, this is no reason for complacency. Also, in certain instances though the decline of indigenous species has been attributed to an exotic i:he evidence available is mostly circumstantial. In spite of these shortcomings this Appendix summarizes such instances. 150

162 151 Table Affi. Indigenous species which are known to be endangered and or declined as a result of introductions in different countries. Countiy/Species Locality Status Reasons Authority AUSTRALIA Melanotaenja eachamensjs Lake Eacham Extinct (?) Translocation of Banao et (Lake Eacham rainbow fish) Queensland (IUCN) mouthbrooder al. (1987) Glossania apricu Galaxia.sfanianu.s Swan River Endangered Introduction of Michaelis (1985) (Swan galaxias) Tasmania Salrno trutta Galaxtasjohnstani (Clarence galaxias) Clarence river, Tasmania Endangered Introduction of Salvelinusfontiia1is do INDIA Cat/a cat/a Some reservoir Decline in Introduction of Shetty et al. populations catches silver carp pres. volume JAPAN Rhodeu.s' ocellatu.s smithi Endangered Introduction of R.o. ocellatus Chiba et al. pres. volume MALAYSIA Trichogaster trichopterus (Snakehead gouramy) Paddy fields, swamps Endangered(?) Introduction of T. pectoralis Ang et al present volume PIT11UPPINES Mistichihys luzonensis (Sinarapan) Native Cyprinid Flock Lake Buhi Lake Lanao Extinct(?) Endangered(?) Introduction of T. mossambica Introduction of Glossogobiu.s giuris Baluyut (1988), De Silva, Juliano et al. (pres. vol.) & Frey (1969) TAIWAN Macropodu.s opercularis almost extinct Due to the introduction of Ainpullarius insularu,n Liao & Liu (pres. vol.) Clariasfuscu.s almost extinct C/arias batrachus do Oryzias latipes extinct Gambzesia affinis do Leiobagru.sfosmosanus population has Micropterus salmoides Liao & Chiu Leiocassis adiposalis been greatly (pres. vol.) reduced Rhyacichthys aspro Mesopristes cancel/at us population has been greatly reduced Poecilia velifera do Erylhroculter ilishaeformis extinct Tilapia zulu do Oreochromis aureus 0. mossambicus 0. niloticu.s Capoeta semfa.sciolata population has been greatly reduced Tricogasrer trichopterus do

163 Appendix IV Ornamental Fishes The inclusion of lists of exotic ornamental fishes in each of the countries in the proceedings will not be a realistic task. In the text lists of ornamental fishes introduced into Malaysia, People's Republic of China, Singapore, Taiwan and Thailand are included in each of the papers on these countries. A list of ornamental fishes introduced to Australia is available from Mr. R. McKay (also in diskette from IBM Compatible PC). The Indian Branch of the Asian Fisheries Society has prepared a list of ornamental fish introduced into India, and this will be published in the Proceedings of the Workshop on Exotic Organisms in India. The particular reference is: Bhaskan, I.S., Reddy, P.S., Elambarathy, B., Subranianium, B. and Lazarus, R.J. (in press), Exotic freshwater aquarium fishes and their role in the aquarium fish trade of India. In addition lists of aquarium fishes introduced into some of the other countries are documented in: Conroy, D.A. (1975), An evaluation of the present state of world trade in ornamental fish. FAO Fisheries Circular No. 335, pp The Committee on Exotic Fishes of the Asian Fisheries Society will attempt to publish a separate document on ornamental fishes in the near future. As much as interest is created in the exotics, there is a need to conserve the stocks of ornamental fish exported from each of the countries in the region because some of the species exported are endemic to specific countries/habitats, and are already cited as endangred species in the IUCN's red data book. 152

164 Appendix V Existing Legislation or Code of Practices Adopted by Individual Countries in Respect of Introducing Aquatic Species The operative legislation of some of the countries has been dealt with in the individual presentations. In this Appendix, a summary of the legislation, and in the event there is no legislation the mechanisms that operate in deciding on introducing a species to that country, is presented. AUSTRALIA: The operative legislation covers all plant and animal introductions to Australia by the Wildlife Protection (Regulation of Export Imports) Act 1982 of the Commonwealth (Federal) Government. The Act is administered by the Australian National Parks and Wildlife Service, and on matters regarding aquatic species technical advice is rendered by the Advisory Committee on Live Fish (ACOLF) of the Australian Fisheries Council. The ACOLF also serves in an advisory capacity for inter-state translocations. Australia is also a signatory to the CITES and the SPREP conventions. INDIA: There is no existing legislature on the importation/introduction of aquatic organisms. However, the Indian Council for Agricultural Research, through the Commissioner of Fisheries, decides on any proposed introductions. India is also a signatory to CITES. INDONESIA: Indonesia has recently adopted the code of practice developed by the European Inland Fisheries Advisory Committee (EIFAC) for the introduction of aquatic organisms (Artmadja Hardjumulia, pers. comm.). However, this informal adoption has yet to be legalized. JAPAN: There are no restrictions or rules governing introduction of exotic species into Japan. Japan is a signatory to CITES and is only bound by this convention. 153

165 154 Mi101 IDRC CR11 rnfin MALAYSIA: The present Fisheries Act 1984, which replaced the Fisheries Act 1963, governs the introductions into Malaysia and also translocations between West Malaysia to Labuan or Sabah and Sarawak and vice versa. The Director General of Fisheries is empowered by Section 40(2) of the Act to issue permits for introductions, and to establish and determine the quarantine procedure and facilities. The above Federal Statute is an addition to the number of State enactments some of which have been in existence since Malaysia is also a signatory to the CITES. PHILIPPINES: There are no laws governing the introduction of aquatic organisms. Most research institutes and universities however, follow strict quarantine measures with imported species. SRI LANKA: There are no laws governing the introduction of aquatic organisms per Se. However, the strict customs regulations act as a safety valve, and imported live organisms are expected to be brought into the country on the recommendation of Zoological Gardens, The Department of Agriculture and in the case of aquatic species, the Ministry of Fisheries. The deliberate release of aquatic organisms in the wild can be carried out only on the authority of the Ministry of Fisheries. Sri Lanka is a signatory to CITES. TAIWAN: There are still no laws/regulations governing the importation of aquatic organism into Taiwan. However, a few governmental organizations have some regulations with respect to certain types or species of fish. Importation of food and ornamental aquatic organisms is under the jurisdiction of the Taiwan Fisheries Bureau and the Council of Agriculture. The final authority for issue of permits lies with the Executive Yuan of the Council of Agriculture, which acts on the advice of Taiwan Fisheries Bureau. THAILAND: A Royal Decree in 1953 prohibited the introduction of many exotic animals and plants. It was amended in 1982 and was made into law in The law prohibits the introduction of 176 species of fish, 21 species of invertebrates and 16 species of algae.

166 TITLES IN THE ASIAN FISHERIES SOCIETY SPECIAL PUBLICATION SERIES Fish Quarantine and Fish Diseases in South and Southeast Asia: 1986 Update Edited by J.R. Arthur. Asian Fish. Soc. Spec. Pub!. 1,86 p. Price: Members, free. Nonmembers, US$5. Fisheries Education and Training In Asia: Workshop ProceedIngs Asian Fish. Soc. Spec. Pub!, 2, 162 p. Price: Members, free. Nonmembers, US$8. Exotic Aquatic Organisms In Asia Edited by S.S. Dc Silva. Asian Fish. Soc. Spec. Pub!. 3, 154 p. Price: Members, free. Nonmembers, US$8. -