MANAGEMENT OF SPINY LOBSTER FISHERY RESOURCES

Transcription

1 Phiips, B.F and A.N.Sastry, 980. Larva Ecoogy. In The Bioogy and Management of Lobsters, Vo. 1 (Ed. by J.S. Cobb & B.F. Phiips), Academic Press, New York, USA. Phiips, B.F and J. Kittaka, Spiny Lobsters: Fisheries and Cuture, Fishing News Books, UK. Phiips, B.F., C.F. Chubb and R.Mevie-Smith, The Status of Austraia s Rock Lobster Fisheries. In Spiny Lobsters Fisheries and Cuture (Ed by B.F.Phiips & J.Kittaka) Fishing News Books, Backwe Scientific Pubications, Oxford, UK. MANAGEMENT OF SPINY LOBSTER FISHERY RESOURCES Radhakrishnan. E.V. and M.K.Manisseri, Lobsters, In: Status of expoited marine fishery resources of India. M.Mohan Jeseph and A.A.Jeyaprakash(Eds.).Centra Marine Fisheries Research Institute, Kochi, 308pp. Sastry, A.N., Peagic arva ecoogy and deveopment, In the Bioogy of Crustacea, Vo. 7, pp , Academic Press, New York, USA. Sosa-Cordero, E., A.M. Arce, W. Aguiar-Davia, and A. Ramirez- Gonzaez, Artificia Sheters for spiny obster P.argus: an evauation of occupancy in different benthic habitats, Journa of Experimenta Marine Bioogy and Ecoogy 229, Synthesis of Workshop Discussion, In Proceedings of the Workshop on Lobsters, CSIRO Pubication. Van Ost, J.V, J.M Carberg and J.T. Hughes, Aquacuture. In The Bioogy and Management of Lobsters, Vo. 1 (Ed. by J.S. Cobb & B.F. Phiips), Academic Press, New York, USA. Yoshimura, T. and H. Yamakawa, Microhabitat and behaviour of setted puerui and juvenies of the Japanese spiny obster Panuirus japonicus at Kominato, Japan. J.Crust.Bio.Bu., S.Ajma Khan Centre of Advanced Study in Marine Bioogy Annamaai University Parangipettai Nationa Biodiversity Authority Chennai, TamiNadu, India

2 NBA Scientific Buetin Number - 8 Copyright: Nationa Biodiversity Authority No part of this pubication may be reproduced, stored in a retrieva system or transmitted in any form or by any means, eectronic, mechanica, photocopying, recording or otherwise without the prior permission of the pubisher. Citation : Ajma Khan S Management of Spiny Lobster Fishery Resources. NBA Scientific Buetin Number - 8, Nationa Biodiversity Authority, Chennai, TamiNadu, India, p32. Japanese Research Group of Fisheries Engineering (JRGFE), Report of observations on the aggregation of aquatic ife on artificia coasta constructions. Fish. Eng., 13(1). Johnson, D.W. and T.Z.A-Abdusaaam, The scaoped spiny obster (Panuirus homarus) fishery in the Sutanate of Oman. The Lobster Newsetter, 4:1-4. Lipcius, R.N. and D.B.Eggeston, Ecoogy and fishery bioogy of spiny obsters. In Spiny Lobsters Fisheries and Cuture (Ed. by B.F.Phiips & J.Kittaka) Fishing News Books, Backwe Scientific Pubications, Oxford, UK. Lipcius, R.N. and W.F. Herrnkind, Contro and coordination of reproduction and moting in the spiny obster Panuirus argus. Mar.Bio., 96, Meagher, T., A review of the practicaity of cutivating pueruus of the western rock obster, Panuirus cygnus in Western Austraia, FRDC Project Report, 92/149, p.62. Mier, R.J., Be a you can be management strategies for Canadian obster fisheries, Fisheries Research, 64, p For further information, pease contact The Chairman Nationa Biodiversity Authority 475, 9 th south cross street, Kapaeeswarar Nagar, Neeangarai, Chennai Printed by : Frontine Offset Printers 26, New Street, Lyods Road, Tripicane, Chennai Ph : Mohan, R. and M.N. A-Amri, 1998, The spiny obster fishery in Sutanate of Oman, Dept. of Fisheries Science and Technoogy, Coege of Agricurure, Sutan Qaboos University, Oman. Nonaka, M., H.Fushimi and T.Yamakawa, The spiny obster fishery in Japan and restocking. In Spiny Lobsters Fisheries and Cuture, Ed B.F.Phiips & J.Kittaka, Fishing News Books, Backwe Scientific Pubications, Oxford, UK. 31

3 Cobb, J.S and D. Wang, D., Fisheries Bioogy of Lobsters, Vo. 1, Physioogy and Behaviour, 463pp, Academic Press, New York, USA. Coin Buxton, Rock Lobster Breakthrough, Fish Farming Internationa, Jauary CSIRO Fact Sheet, No. 60, August 2003, CSIRO Marine Research Pubication. Fish News, Austasia Aquacuture, December Garderner, C and S. Frusher, Wi the remova of cosed seasons from the management system of the Tasmanian rock obster fishery harm the resource? Technica report series, No. 14, pubished by Marine Research Laboratories, TAFI, University of Tasmania. Griffin, D., Modeing the transport of tropica spiny obsters arvae Panuirus ornatus in east Austraian waters. Proceedings of the Workshop on Lobsters, CSIRO Pubication. Herrnkind, W.F., Spiny obsters: Patterns of movement. In The Bioogy and Management of Lobsters, Vo. 1 (Ed. by J.S. Cobb & B.F. Phiips), Academic Press, New York, USA. Hiborn, R., T.A. Branch, B.Ernst, A. Magnusson, C.V. Minte-Vera, M.D. Scheure and L. Vaero, State of the Word Fisheries, Annu. Rev. Environ. Resour., 28. Hothuis, L.B., FAO species cataogue. Marine obsters of the word. FAO Fisheries Synopsis, Vo. 13, No. 125, Food and Agricuture Organization of the United Nations, Rome, Itay. 30 CONTENTS Particuars Page No. Introduction 1 Leve of production of obsters in India 2 Species composition 3 Bioogy of obsters 3 Life history of obsters: 4 Works on bioogy of obsters in India 5 Stock assessment 7 Fishery management objectives and strategies 7 Bioogica Consequences: 8 Economic Consequences: 11 Socia Consequences: 13 Administrative Consequences: 14 Environmenta consequences 16 Other aspects to be pondered 16 Recruitment overfishing: 17 Growth overfishing 17 Fishing mortaity rate 18 Expoitation rate 18 Management strategies in other countries 18 Lobster stock enhancement 20 Artificia sheters 22 Introduction of pots which can trap ony arger obsters 23 Reference points and performance indicators 24 Bioogica reference points 25 Economic performance indicators 26 Management committee performance indicators 26 Management in India 27 Concusion 28 Acknowedgement 29 References 29

4 and arva duration shoud aso be attempted besides efforts to make them overcoming stress. Standardization of arva ife feed, commercia Artemia repacement diets and formuation of arva feed are aso equay important. Studies shoud be undertaken to get current estimates of stocks for a the species. What is worrying is the arge scae expoitation of juvenies. A study conducted in the Kanyakumari region by a researcher in the Centre of Advanced Study in Marine Bioogy of Annamaai University showed that 70% of the anded obsters were juvenies. This is a dangerous situation. If the stock position reveas fewer aduts, a moratorium on obster catch shoud be brought in so that the stocks wi be in a position to rebuid themseves. The agencies which undertake and promote obster fattening shoud be dissuaded from doing it as juvenies are hed in cuture faciities unti they attain the marketabe size and harvested. As no opportunity is given to these organisms for reproduction it is aso detrimenta to the obsters. Among a the commerciay important invertebrates, obsters are gracefu organisms. No stone shoud be eft unturned in protecting and conserving the obster resources. Acknowedgement The author is thankfu to Prof.T.Baasubramanian, Director, Centre of Advanced Study in Marine Bioogy for the encouragement and the authorities of Annamaai University for the faciities. References Be, J.D., 2004., Key issues of the sustaining aquacuture production of the spiny obster Panuirus ornatus, in Vietnam. In Proceedings of the Workshop on Lobsters, CSIRO Pubication. 29

5 season have an adverse impact on the breeding stocks as it wi affect reease of eggs and thereby recruitment. Unfortunatey peak fishing coincides with peak breeding season of the obsters in most of the fishing areas. Seasona cosures around the time of breeding have been effectivey used as a reguatory measure in singe species fishery of the subtropica seas. Aong the southwest and southeast coasts, the operation of tramme nets brings in substantia quantities of juvenies. Tramme net is a destructive gear for obsters. With the beginning of ive obster export, expoitation of juvenies and undersized obsters has been on the increase. The overseas demand is higher for smaer sizes. India exports undersized obsters aso whie other countries have enforced strict reguations on size of these shefishes fished and exported. This situation has affected the obster resource of the country to a great extent. Therefore, reguatory measures need to be formuated and enforced for sustainabe expoitation of obsters in the country. Radhakrishnan and Manisseri (2003) recommended the foowing management measures. Impose ban on both capture and export of egg bearing obsters. Reeasing of berried obsters back into the sea is to be made mandatory. Enforce Minimum Lega Size for capture and export. Minimum Lega Sizes recommended are : P. homarus - 60 mm CL, P. ornatus - 80 mm CL, P. poyphagus - 70 mm CL, T orietais - 60 mm CL. Concusion In order to avoid commercia extinction of obsters in Indian waters, priority shoud be given for competing the arva ife history of spiny obsters in the aboratory/hatchery and for perfecting the technoogy for arge scae production of phyosoma and pueruus. This shoud be given top priority by a the institutes deaing with the fisheries and aquacuture. Genetic manipuation for shortening the arva ife history Introduction Marine resources in Indian waters are common property resources. The roe of Government as custodian of the marine resources on behaf of the genera community is to ensure that marine resources are used in an ecoogicay sustainabe manner and as efficienty as possibe, whie yieding a return to the community. Experience wordwide has shown that there is unrestricted use of marine resources and the consequent decine in the stocks. This is attributed to the foowing factors: Popuation growth Rise in the internationa demand for fish Improvements in the interna market infrastructure Modern technoogies Environmenta conditions High price for certain species and Poor fisheries management. The situation warrants management. In carrying out the management of the resource, Governments have the responsibiity of ensuring that the basis for the sharing of the resource among a users is ceary understood and accepted as equitabe and that the aocation of fishery resources and their eve of utiization are consistent with the needs of present and future generations. When scientific data or evidence on some bioogica parameter for a fishery is acking, the management decisions wi not be that effective and it is the responsibiity of the scientists and the fisheries research institutes to provide scientific data and the management pans. In India such a pan is urgenty and very bady needed for the obster resources. 28 1

6 Lobsters are one of the most vauabe and highy priced seafoods. In the past two decades, obsters have become very popuar in the word markets. Wordwide, the market price for obsters tended to rise in response to suppy and demand rather than the costs invoved in the production (capture and processing). This attractive price encouraged fishermen to aggressivey expoit the fishery with no concern to its ongterm sustainabiity. As obsters became scarcer, the price kept rising unti some kind of consumer resistance deveoped towards high obster prices. In spite of this resistance, obsters continue to command a premium among the crustaceans aong with shrimps. Among them, the spiny obsters (rock obsters) especiay the ive ones fetch the highest price. Even though the obsters in India form ony 0.12 of the tota marine andings, they are an important export commodity comprising of 1.07% in quantity and 2.59% in vaue (Radhakirishnan and Manisseri, 2003).Being the gourmet s number one choice and epicurean s deight heavy demand is there in the internationa markets and the obsters are offered high prices. This has ed to increased expoitation of obsters in the recent years. The mutispecies and mutigear fishery invoving both traditiona and mechanized sectors poses probems for effective management. The various options avaiabe for their management are presented here. Leve of production of obsters in India Even though obsters have been caught since yore, the fishery improved in the twentieth century and consequenty the stock position has become precarious. The fishery increased from 347 tones in 1965 to 2,991 tones in The highest anding of 4,082 was recorded in After that the catch has been fuctuating around 2, 400 tones. Even though the obsters are distributed throughout the coast ine, northwest, southwest and southeast contribute more to the anding. 2 Management in India Radhakrishnan and Manisseri(2003)compied information about the management of obsters in India. According to them currenty, no management reguations are in force to contro fishing of obsters in India. There are no restrictions on fishing such as minimum size of capture, types of gears used, tota number of crafts empoyed and season of fishing. Unike the singe species fishery of the temperate and subtropica countries, the obster fishery in India is muti-species and expoited by divergent gears invoving both traditiona and mechanized sectors. The fishermen ured by the high prices offered for obsters are expoiting the resource indiscriminatey, in the absence of any reguation or contro on fishing activity. Therefore framing and impementation of management measures wi have to take into account the bioogica, socia and economic aspects. On the northwest, avaiabe scientific information ceary indicates that the resources of the spiny obster P.poyphagus and the sand obster Thenus orientais are overexpoited. The current anding of obsters in India constitutes ony 58% of the peak catch once obtained in 1985 and consists of smaer specimens which bring esser vaue. In Mumhai. average anding during has come down by 57 compared to production during The situation is simiar at Verava and at other major fishing centres aong the southwest and southeast coasts. At Tuticorin neary 43% of the obster andings are by trawers and a situation simiar to the northwest prevais here aso. But, one of the major constraints is that obsters appear ony as by-catch in traw fishery and no direct reguations can be enforced to contro fishing of one resource aone. But restrictions on juvenie fishing in inshore waters by gi nets, do nets, stake nets and cast nets wi have to be enforced so that overexpoitation coud be contained. Simiary, arge scae expoitation of egg bearing femaes during peak breeding 27

7 i. changes in TACC (tota aowabe commercia catch) in subsequent years and ii. changes to the minimum size imit and changes to the fishing season. Economic performance indicators Based on the economic objectives for the fishery, the foowing performance indicators are used to assess the economic status of the obster fishery: 1. Gross Vaue of Product (GVP); 2. cost of management programs compared with GVP; 3. return on Investment (RO) and 4. determination of any major operating cost increases (eg. possibe future oss of fue rebate) Management committee performance indicators The primary responsibiity for ecoogicay sustainabe deveopment of the obster resource rests with the government. However, to assess the effectiveness and efficiency of the management of the resource, and to provide for transparency in the management process and improve accountabiity, performance indicators are required. The primary performance indicators used to assess the effectiveness and efficiency of the management by government is the acceptance of advice from the enforcing agency and the quaity of the information the government department suppies to the higher-ups. In fact, of the tota andings, 43.7% came from the coast of Gujarat and 25.4% from the coast of Maharashtra during Whie Tami Nadu contributed 14.6%, Keraa contributed 13% during the above period. The average size of obsters anded has decreased consideraby over the period of time(radhakirishnan and Manisseri, 2003). Species composition Out of the 14 species of ittora and 6 species of deep sea forms occurring in India ony 4 species of ittora species contribute to the fishery. Whie Panuirus poyphagus and Thenus orientais are caught mainy from the northwest coast, P.homarus is caught from the southwest coast. P.ornatus, P.homarus and Thenus orientais are caught from the southeast coast of India. P.versicoor is caught in Tuticorin waters aong the southeast coast of India. arge numbers. Whie the traw net contributes much to the andings, gears such as traps, gi nets and tramme nets and the rest. Bioogy of obsters Spiny or Rock Lobsters (Crustacea: Decapoda: Painuridae) are common throughout tropica and subtropica seas (Hothuis, 1991) where they form some of the most important commercia fisheries of the word. Ecoogicay, painurids are important inks in marine food webs. A nocturna species, the obster is an omnivorous scavenger with a preference for musses, whie juvenies feed mosty on barnaces (Phiips and Kittaka, 2000). According to Phiips et a. (2000), painurids are major predators of various benthic species (e.g. snais, cams, urchins) and important prey of arger predators (e.g. sharks and some finfishes). The spiny obsters have a particuar preference for cora and rocky reefs that are washed by sandy surfs. They inhabit mosty cear waters with ow runoff on isands or continents. They are among the 26 3

8 argest of crustaceans: the tota body ength sometimes attaining a ength of 60cm (Lipcius and Eggeston, 2000). The body parts are divided into cephaothorax, which consists of the fused head and thorax, and an abdomen with their respective appendages (Phiips and Kittaka, 2000). Appendages on the cephaothorax incude the eyes, the antennae and antennues, which provide protection, mechanoreception and chemoreception (Lipcius and Eggeston, 2000); the mouthparts, which incude the mandibes, maxiae and maxiipeds; and five pairs of waking egs. The ventra portion of the cephaothorax forms a sternum, which bears the gonopores at the bases of the 3 rd pair of pereiopods in femaes and 5 th pair in maes. In the abdomen of the maes, the first two pairs of peopods are often formed into copuatory organs, whereas in mature femaes the peopods become setose to encose the externa egg mass (Lipcius and Herrnkind, 1987). Posteriory, the 6 th abdomina somite forms the tai fan, consisting of uropods and teson, which enabes the swift backward escape response (Cobb and Wang, 1985). Life history of obsters: The spiny obsters carry eggs externay and cutch size varies according to the size of the obster. Gardener and Frusher (2000) reported that the size of the egg cutch is aso infuenced by the size of the sperm packet that the femae received at mating. In genera, it ranges between 35,000 to over 750,000 eggs (Mohan and A-Amri, 1998; CSIRO Fact Sheet, 2003). Incubation period for the eggs is reativey short, being about three to five weeks (Cobb and Wang, 1985) but the arva period, however is asting about 11 months (Johnson and A- Abdusaaam, 1991). Bioogica reference points Considering the stated bioogica objectives for the fishery, the foowing reference points are used to assess the stock status of the obster fishery: expoitation rate - indicates the eve of avaiabe obsters taken by the fishery. catch rate - directy reative to current stock abundance. egg production - refects reproductive capacity of the fishery. abundance of pre-recruits - provides a forecasting too on future stock abundance. mean size of rock obster - indicates changes in stock structure. In determining the annua reference points to measure performance of the fishery, the management committee is guided by the foowing principe: to maintain and improve the average catch rate above the particuar eve to maintain the spawning biomass at a eve which sustains the reproductive capacity of the stock. When one or more of the reference points described are reached or exceeded, the management committee undertakes the foowing actions: 1. notify the government agencies and participants in the fishery as appropriate, 2. undertake an examination of the causes and impications of triggering a reference point and 3. consut the need for aternative management strategies or actions, which incude: 4 25

9 Other management practices incude 1. Limited entry fishery-imiting number of boats/traps. However when the number of traps boats was restricted, fishermen made good by intensivey using the aowed pots. 2. Introducing quota system-tota aowabe commercia catch (TACC). It is in vogue in many countries incuding Austraia. 3. Maintaining of commercia catch ogbook to be made compusory. 4. Cosure of fishery during peak period of reproduction and 5. Creation of obster sanctuaries Reference points and performance indicators Reference points and performance indicators are aso used in management. These are agreed quantitative measures used to assess performance of the fishery based on ceary defined management objectives. Reference points begin as conceptua criteria which capture in broad terms the management objectives for the fishery. To impement management the conceptua reference point is converted into a technica reference point, which is cacuated or quantified on the basis of bioogica or economic characteristics of the fishery (Caddy and Mahon 1995). Reference points used for rationa expoitation of obster resources are paced in two categories: target reference points and imit reference points. Target reference points are considered as indicators of stock status which are a desirabe management target, whist a imit reference point is an agreed eve at which stock stress may occur, and immediate action is required to remedy the situation before ong term damage to resource productivity may resut. Fertiization is externa; the mae deposits a spermatophoric mass on the femae s sternum. Fertiization occurs when the eggs are extruded onto the abdomen and peopods (Lipcius and Herrnkind, 1987). The femae carries the eggs on the abdomen unti hatching. Unike other crustaceans, eggs of spiny obsters pass through a naupiar phase before hatching into the distinctive phyosoma arvae (Sastry, 1983) which are transparent and measure about two mm in ength (CSIRO Fact Sheet, 2003).However it shoud be checked for the Indian obsters. The spiny obsters have ong peagic arva phases, during which time the arvae can be transported ong distances by oceanic currents (Griffin, 2004). It has been reported that the arvae are transported over thousands of mies. This eary peagic arvae are known as phyosma stage that have an extended oceanic arva period of up to 11 months before returning to inshore waters as puerui where they sette into sma hoes and crevices in the reefs and seabed (Johnson and A- Abdusaaam, 1991; CSIRO Fact Sheet, 2003). The number of puerui setting on the fishing grounds every year may depend on the success of the previous year s migration and breeding (Phiips et a., 2000). Spiny obsters exhibit 5 major phases within their ife cyce: egg, phyosoma arva, pueruus (post-arva stage), juvenie and adut (Phiips and Sastry, 1980). During growth obsters ike other crustaceans undergo mout (shedding of hard outer she). Shorty before reaching aduthood many spiny obsters undergo movements (migrations) from the nursery habitat to the characteristic deeper reef habitats, where reproduction occurs (Herrnkind, 1980). Works on bioogy of obsters in India In India studies on bioogy and fishery of important species have been carried out by Centra Marine Fisheries Research Institute (CMFRI) 24 5

10 at Verava. Mumbai. Caicut. Vizhinjam. Tuticorin. Mandapam and Chennai. Growth, as in other crustaceans, is manifested by periodica shedding of exoskeeton (mouting). Studies on food and feeding habits of obsters show that these animas generay feed on smaer crustaceans, mouscs and poychaetes. Panutirus poyphagus is normay found in muddy substrates and sometimes on rocky bottoms whereas P. homarus and P ornatus inhabit rocky and reef areas. Berried femaes of P. homarus are normay observed in inshore areas. Size of obsters in the fishery generay ranges from 35 to 125 mm in carapace ength. P. homarus attains a tota ength (TL) of 320 mm, P. poyphagus, 450mm and P.ornatus 500 mm. Growth is identica in juvenies but differentia in the aduts. In P.poyphagus, sexua maturity (50% eve) is attained at 175 mm TL for femaes, whereas majority of maes mature at 265 mm TL. P. poyphagus breeds amost throughout the year. but maximum number of femaes in berried condition are noticed during August-October when about 80% of femaes are egg bearing. Spiny obsters here are highy fecund and fecundity ranges from 50,000 to 1, eggs depending upon the species and the size of obster. In P. poyphagus, recruitment of young obsters measuring beow 100 mm (<5Og) generay takes pace during December-January. The occurrence of berried femaes in the m depth zone indicates that there is no arge scae movement of femaes to deeper waters for breeding. P.homarus attains sexua maturity at 55 mm carapace ength and majority of femaes start breeding at sizes above 60 mm CL. Though the species breeds throughout the year, peak breeding is from November to December aong the southwest coast and January-March aong the southeast coast. P. ornutus, on the other hand, starts breeding at 90mm CL (250mm TL). P homarus normay breeds in the shaow waters. Occurrence of adut P ornatus at m depth indicates that the species breeds probaby at reativey deeper waters (Radhakrishnan and Manisseri, 2003). 6 It is we known that spiny obsters gather in sunken ships. This is due to the behaviour of obsters, which hide in dark paces during the day. Because of this, aying structures imitating obster habitats may ead to the formation of fishing grounds (JRGFE, 1976). A major feature of the Cuban obster fishery has been the introduction of the artificia sheters known as Persqueros. Simiary, the spiny obster fishery in Mexico uses artificia sheters caed Casitas. However, the use of artificia reefs to increase fishery production remains controversia due to the hypothesis that the use of artificia sheters coud ead to overexpoitation of the resource as they attract naturay dispersed animas to aggregate and thus increase vunerabiity to capture (Phiips and Kittaka, 2000). Another important concern is that increased predation pressure at or near artificia reefs coud outweigh the benefits from potentia increases in production. Hence, a detaied ecoogica study shoud be undertaken before deciding to impement artificia sheters to augment obster stocks. Evauation of enhancement programmes is aso in pace in many countries. Introduction of pots which can trap ony arger obsters Pots of various sizes and shapes are used throughout the word. Lobsters traps made of canes besides beehive pots of wire mesh on stee frames or wedmesh mouted pastic are used in the fishery. The size varies depending upon the species invoved. Pots are usuay set overnight and haued in the morning. Esewhere hydrauic or mechanica pot hauers are used. One of the reasons for faiure was the mismanagement of the obster potting system. The performance of imported pots may not be appropriate for the oca condition as the growth rate and size at maturity differ. 23

11 Contrary to this, some argue that if surviva of puerui in nature is ow, then the remova of some puerui for ongrowing coud resut in better production. In New Zeaand, thousands of puerui and juvenies are coected for commercia ongrowing by those retiring from commercia fishing in exchange of their quota (Synthesis of Workshop Discussion, 2004). A different approach is being considered in Austraia to return cutured femaes to the wid to appease those objecting to the remova of puerui. Severa spiny obster species can be ongrown from pueruus or juvenie stage to market size in 1 or 2 years time athough many probems such as high costs, feed conversion and surviva persist and sti need to be addressed. They further state that in the ong term puerui cutured from eggs wi be more acceptabe and that wi aso ead to a more reguar and predictabe suppy of stock. Artificia sheters Carefu consideration has to be appied to the nature of artificia habitat creation. Simpy creating a coection of bouders on the seabed may be totay inappropriate to form an artificia reef specificay for obsters. Lobster pueruus and post-pueruus prefer to ive in sma hoes ony sighty arger than their body sizes (Yoshimura and Yamakawa, 1988). If such hoes are not avaiabe then this juvenie stage is unikey to survive. Hence, habitat seection is an important criterion when deaing with enhancement tasks. Physica characteristics of the sheters are important as mutipe den openings, shaded cover etc coud provide safe hiding for communa obsters. In addition to these physica characteristics, oca habitat features are aso important in determining the success of artificia sheters in attracting and concentrating obsters. Sites without or distant from habitats rich in obster food shoud be avoided when pacing artificia sheters (Sosa-Cordero et a., 1998). Stock assessment In a recent study by CMFRI on P. poyphagus from Mumbai waters, the age and growth was determined based on the engthfrequency method. Growth during the first 3 years was found to be identica in both sexes. The species attained 85 mm, 145 mm and 205 mm at the end of I to III year respectivey. Thereafter, the maes grew faster than femaes, measuring 265 mm, 315 mm, and 355 mm successivey ti the end of sixth year. Femaes measured 255 mm, 290mm, 320 mm, 345 mm and 365 mm respectivey by the end of 4 to 8 year. The frequency of mouting is more and the intermout period is shorter in juvenies. With the advance in age, the intermout period gets proonged and the number of mouts gets reduced. The ength increment per mout is neary constant during the juvenie and adut phases. Six to seven broods appear to be recruited annuay to the fishery. November December is the peak period of recruitment for sma sized juvenies. Stock studies revea that tota mortaity coefficient Z is 1.76 for maes and 1.15 for femaes and the natura mortaity coefficient M is 0.33 for maes and 0.35 for femaes. The fishing mortaity coefficient F deduced from these equas 1.43 for maes and 0.8 for femaes. The tota stock estimated is 453 t, the standing stock 271 t and the maximum sustainabe yied 168 t (Radhakrishnan and Manisseri, 2003). Fishery management objectives and strategies Fisheries management is the objective of many maritime countries to protect and sustain their vauabe fishery resources for the we being of their present and future fishing industry. Its compexity may depend on the extent of the fishery itsef as countries with ong coastines and diversified fishery resources have far more probems than smaer countries. India is a very good exampe for this. With many species of commerciay important species, varied gears used in 22 7

12 expoitation and diversity (muti-ethnic) among peope engaged in fishing, India has many probems in managing the fishery resources, obsters notwithstanding. The fishery management pan shoud be prepared keeping in mind that there may be severa reasons for reguating a fishery. In addition to conserving the resource and improving economic performance, fishery management measures are used to prevent or mitigate conficts among user groups to encourage the distribution of benefits among users and to protect socia vaues and ife styes. There are five main issues that fishery managers must consider when deciding which management measures to appy: 1. Bioogica Consequences 2. Economic Consequences 3. Socia Consequences 4. Administrative Consequences and 5. Environmenta consequences Bioogica Consequences: The main objectives here are: 1. To main rock obster popuations at sustainabe eves across the fishery and 2. To harvest rock obster at a size ikey to provide for adequate eves of recruitment. Accurate data that describes both the fishery and the markets reevant to the fishery are important components in its effective management. Poicy makers shoud have before them three sets of basic figures: 8 experiments have mainy focused on refinement of hatchery technoogy. Surviva rates obtained for different species of obsters at different abs upto stage IV or pueruus stage vary from 10% to 88.6%. Larva surviva rate is the crucia imiting factor in obster cuture Successfu arva rearing to metamorphosis (post arva and juvenie stage) has been achieved by ony a few institutions. As a resut, argescae arva cuture of spiny obsters has sti not been achieved despite significant advances in the understanding of their bioogy and ife history. Recent study of Tasmanian Aquacuture Institute suggests that they have succeeded in reducing the arva deveopment period from two years to just one year (Fish News, 2004). Further research shoud focus on improving the surviva rates of arvae. Key to this is better understanding and contro of arva heath (Coin Buxton, 2005). It takes up to 3 to 4 years or more under optimum conditions for spiny obsters to reach commercia size from hatching. The ong cuture period required for attaining to attain market size particuary when compared with some cutured finfish or shrimp species is the main constraint to commerciaization of obster cuture. In spite of significant deveopments in obster hatchery technoogy and grow-out techniques, there is a tendency to rey on wid sources of juvenies for on growing which in itsef coud negativey impact the wid fishery (Lobster Propagation Workshop, 1999). It was stated that surviva of puerui coud be greaty increased in cuture than in wid, provided catches of puerui are a sma proportion of those avaiabe. Meagher (1994) concuded that obster cuture based on wid sourced juvenies appears to have commercia prospects, but it shoud not proceed uness it can be concuded that the harvested puerui are excess to those required for maintenance of the existing wid-catch fishery. 21

13 Training in quaity enhancement of obster catches through better post catch handing techniques aso contributes to improved returns from the fishery by specificay targeting the high vaue niche markets requiring fresh and ive obster suppies. This aso encourages fishermen to use traps to and obsters unharmed. the best current estimates of the potentia sustainabe yied from the stock the present catch eves and pans for increase in the catch Lobster stock enhancement There are numerous exampes of obster stock enhancement studies invoving a range of species from the tropics to temperate regions. For Homarus americanus, some groups in North America raise the animas to their first benthic stage (Stage IV arvae of cawed obsters) after two weeks in cuture and then pace them directy on cobbe and other heterogeneous habitats. These animas are approximatey 15mm tota ength. Other groups hod the obsters in a hatchery environment unti they are 40-50mm tota engths and then simiary distribute them to the seabed. Other groups grow animas to mm tota ength, and mark them with pastic/genetic tags before reeasing them in the wid for studying the efficiency of stock enhancement programmes. Many studies and practica investigations have been undertaken in Japan to promote the increase of this resource. Research on spiny obsters began in 1899 with the experimenta hatching and rearing of the phyosoma in Japan (Nonaka et a., 2000). Kittaka (1989) was the first to achieve success in competing the deveopment of arva stages up to pueruus stage in Panuirus japonicus. Thus, a period of amost 100 years eapsed between the initia research and the achievement of this goa. Since then many attempts have been made to improve the surviva rates of cutured arvae. The main obstace is the extremey ong deveopment period and the poory understood requirements of the phyosoma arvae (Van Ost et a, 1980). Therefore, the earier It is necessary that bioogists, economists and administrators are then required to interact with each other to understand the respective objectives, the data required and finay manner in which the data shoud be integrated to provide for an effective management strategy. Unfortunatey, detaied data are not avaiabe covering the entire ength of the country. Reiabe information on the bioogy of a the obster specie, estimates of avaiabe stock of a the species and historica management efforts to increase the stock are not readiy avaiabe. Most importanty, there is no major programme to coate fishery data for the obster. Data exist in terms of taxonomy, seasona avaiabiity, size range and distribution aong the coast of India. More importanty, an appreciation of the need for such data has arisen as the importance of the obster resource has been reaized. The coation of vauabe information reating to obster popuation dynamics has been ignored. Understanding the movement of the phyosoma arvae, the settement of pueruus, the growth of juvenie animas, and the dynamics of the fishabe stock incuding an estimate of the reative abundance of the femae breeding popuations is highy reevant to the management of the fishery. Routine assessments of the fishery are required that incude an estimate of the expoitabe biomass (weight or number of obsters above the ega size), the reative impact of harvesting on recruitment to the fishery (this is normay egg production as stock recruitment reationships are difficut to obtain) and a harvest strategy evauation mode that aows predictions of the consequences 20 9

14 of change in management (increasing or decreasing the aowabe catch, increasing or decreasing the fishing effort). The important issue is not the vaue but the trend. Thus the data needs to be coected over a number of years to see whether under the current management regime, egg production and expoitabe biomass is increasing or decreasing. The second component of bioogica research is an understanding of natura variabiity in the resource. This is very compex issue and requires an understanding of the processes that resut in good and bad arva recruitment and the factors that reguate surviva from arva settement to recruitment to the fishery. Attention shoud aso be directed towards the potentia impact of the frequent incidents of upweing and harmfu aga booms on the arva and juvenie popuations. Ony imited data are avaiabe on such important environmenta issues. In addition, the impacts of goba warming and change of ocean currents on the obster popuations coud aso revea whether the coapse of fishery if any is due to mismanagement or in part, to natura phenomena, as Be (2004) stated that ensuring sufficient spawning stocks to produce an abundant suppy of eggs is no guarantee that there wi be consistent suppy of puerui. The vagaries associated with the surviva of panktonic stages and the variations in the oceanic currents wi mean that puerui suppy changes each year. The possibe impact of environmenta parameters on the surviva and recruitment of obsters has to be evauated. Another area of research invoves the potentia for remediation (suppementation) of over fished stocks and/or the enhancement of stocks. The genera objective shoud be to conduct high quaity research focused on critica issues such as: Improving prediction of popuation changes (both short term and ong term) A maximum ega size to protect arger femaes A cosed windo size to protect mature nonovigerous femaes A maximum trap entrance size to excude smaer obsters Increased minimum ega size to permit more obsters to spawn before their catch However, it is necessary that studies shoud be done before arriving at management measures introduced in a fishery. The current debate over obster conservation has focused on whether the egg production from the femae popuation is sufficient to maintain the stocks. Whie the issue of recruitment over fishing is critica to the future of the fishery, the issue of growth over fishing is aso important. In the short term, impementing restrictive management contros wi mean ower incomes to the fishermen. This needs to be addressed by the government. When obster fishing is restricted to ony a few coasta ocations, the governments provide support during periods of enforced conservation measures. This even incudes temporary financia compensation and other forms of socia wefare assistance. In the onger term, propery enforced conservation measures start to positivey impact the fishery, so ensuring the economic independence of fishermen for future generations. The best exampe of such a successfu management approach is the Western Austraian obster fishery, where we panned management approach with strict enforcement yieding resuts with a consistent output of over 11,000 tons each year (Phiips et a, 2000; Hiborn et a., 2003). The Marine Stewardship Counci has accredited the western Austraian rock obster fishery as environmentay and commerciay sustainabe in 2000 for the first time for any fishery in the word

15 the biomass. In genera it is reasonabe to say that a stock is growth overfished in the bioogica sense if F exceeds F MSY. The term bioogica is used to indicate that ony the yied in terms of biomass measured in weight units is considered. Thus the vaue of the yied and coast of fishing are being disregarded here. Fishing mortaity rate The term Fishing Mortaity Rate (FMR) is a technica term referring to the instantaneous rate at which animas are removed from the popuation by fishing. In the obster fishery, it refers primariy to obsters that are anded in the catch. Expoitation rate Information on this is very important in management. It is referring to the fraction of deaths caused by fishing. For managing the obster fishery resources it is important to cacuate the expoitation rate which gives the maximum sustainabe yied. Management strategies in other countries Various management measures foowed in other countries are aimed at maximizing reproduction. These incude a minimum ega size imit and the prohibition of anding gravid femaes. However, considerabe attention is now being focused on issues ike quota or imitation on the number of traps that each fisherman can have in the water and a imit on the number of obsters that can be harvested commerciay. For exampe, Nova Scotia obster fishery foows the foowing management measures to increase egg production (Mier, 2003): Reease of ovigerous femaes Tai notching ovigerous femaes so that they cannot be taken even if nonovigerous 18 Defining processes and mechanisms that contribute to natura avaiabiity of popuations Defining reationships between habitat characteristics and productivity Providing aternative measurement approaches Strengthening coaborative approaches in bioogica, economica and administrative issues Restoring and enhancing stocks and 7 Determining the viabiity of aquacuture to support stock enhancement As a consequence of bioogica research outcomes, the management measures can be undertaken in the form of size imits, gear restrictions, catch targets, cosed areas and seasons etc. Economic Consequences: The main objectives here are: 1. To maintain the economic returns from the fishery at a eve which provides for fair and reasonabe benefits to fishers. 2. To optimize yied from the fishery. 3. To recover an economic return from obster fishers sufficient to cover attributed costs of management, research and compiance for the fishery. 4. To provide for economic efficiency and fexibiity in management arrangements by deveoping harvesting strategies that minimize costs and 11

16 5. To protect the resource through the provision of adequate compiance resources. Athough economic research need not be a continuing process, periodic surveys have to be undertaken to gain an understanding of the economic consequences of the reguations imposed on the fishery. This shoud aso be performed before any actua reguatory measures are imposed to gain a feeing of what wi be the economic consequences if the conservative measures are imposed. In genera, economic consequences incude changes in the net economic benefits to harvesters, processors, distributors, marketers and consumers. The net benefits are reated to andings (amounts and seasona patterns); fishing patterns; harvesting capacity; harvesting practices (fishing techniques, product handing); by catch; product utiization (discard rate, grading); anded product forms; harvesting costs; gear conficts; gear oss; empoyment in harvesting and processing; safety; saes/revenues etc. In the market sector, net benefits are reated to prices (eves and seasona patterns); product quaity and forms; product utiization; product avaiabiity patterns; imports and exports; and consumption patterns. The management pans shoud be designed and impemented in such a way that the pan offers the most favorabe economic consequences to the obster fishing industry. A good management pan shoud ensure better incomes for those associated with the fishery in the ong term whie costs decine through consoidation. One shoud aso expect growth in net incomes over time when stock conditions improve. In case a system is introduced where the obster fishers require icenses, provisions such as permission to se their own fishing icenses (in case of any restriction imposed earier as a contro measure imited entry to fishing) woud offer economic benefits to the fishermen and Recruitment overfishing: A obster resource can be considered over fished when it is harvested at a rate that resuts in egg production from the resource, on an egg-per-recruit basis, that is ess than 25% of the eve produced by an unfished popuation The average femae obster shoud be aowed to ive ong enough to produce at east 25% of the eggs that she woud produce if she ived her natura ife. It may be impossibe to judge the egg production from an unfished popuation, since the obsters have been fished for many years. However, it shoud be easier to cacuate the fecundity of a femae that ived its natura ife as specific bioogica parameters such as how often a femae produces eggs, how many eggs it spawns each time and ongevity of a femae are we known from studies of Painurid species in other fisheries. Overfishing often refers to depeted stocks. Stock depetion and stock coapse are caused by recruitment over fishing, such that the adut popuation is fished so heaviy that it did not have the reproductive capacity to repenish itsef. Even if obster recruitments are good as seen in Western Austraia, scientists are concerned that there is a high risk of recruitment over fishing. The reationships between stock and recruitment and estimations of natura mortaity have proved to be one of the most difficut things to quantify. Therefore, the most difficut thing to achieve is to win over support, particuary from fishermen, about the benefits of protecting breeding stocks. Growth overfishing Growth oversfishing occurs when the effort is so high that the tota yied decreases with increasing effort. The obsters are caught before they can grow to a sufficienty arge size to substantiay contribute to 12 17

17 participants) but the efforts have resuted in a much-improved industry compared to previous years when management was poor. However its practicaity in India shoud be checked. The immediate need in India is to estabish a reiabe statistica database on andings and fishing effort, to start focusing on high quaity scientific studies of obster popuation dynamics and their bioogy; estabish a suitabe and effective management pan based on the outcome of the research and finay to impement the pan with strict surveiance and enforcement. Environmenta consequences The objectives here are: 1. To minimize the environmenta impact of spiny obster fishing and 2. To minimize potentia conficts with other users of marine resources The strategies invoved here are promoting environmentay sensitive fishing practices in the industry and promote actions that reduce fishery impacts and identifying the potentia for conficts with other marine resource users and determine strategies to reduce these conficts. Other aspects to be pondered The managers shoud aso be famiiar with the foowing aspects such as: Recruitment overfishing Growth overfishing Fishing mortaity rate and Expoitation rate motivate the financia sector to offer fishermen more favorabe terms on credit, especiay when combined with improved prospects for stock rebuiding. These provisions make good sense, particuary when adequate stocks are rebuit and a percentage of fishermen are wiing to retire due to age, heath reasons or persona circumstances. Socia Consequences: The main objectives here are 1. To maintain and provide for reasonabe eves of pubic access to the spiny obster resource. 2. To ensure a high eve of awareness of occupationa heath, safety and wefare issues in the fishery. 3. To keep the community informed regarding the status of the rock obster fishery and 4. To maintain the deveopment nature of the spiny obster fishery. Studying marine resource-dependant communities is essentia when deaing with fishery management pans. The coasta fishermen communities are marine resource-dependant communities in our country. In regions where the obsters resources are more such as in northwest, southwest and southeast coasts of India, in view of good prices, the communities are very much dependent upon these resources. A pan that aows atera mobiity into and out of the obster fishery is ikey to offer the most benign socia consequences both in short term and ong term (in case entry to fishing wi be restricted in future to rebuid the stocks). To the extent that new entrants from other fisheries are not perceived to damage the we-being of currenty active fishermen, the inkages and reationships between obster producers 16 13

18 and producers in other fisheries wi be strengthened. Ony then woud a stronger sense of community emerge. There woud be itte or no disruption to empoyment, demographics, famiy stabiity, socia stress and socia networks in the communities, at east in the short term. However, if open access eads to further stock depetion, this wi ead to economic hardship in the obster industry and the socia heath of these communities coud suffer in the ong run. Hence, it is essentia that any fishery management pan first attempts to conserve the stocks for a certain period, ensuring that adequate stocks are rebuit and ony then permit for increased access granted in a gradua step by step manner. Once, impemented, this access pan is ikey to be perceived as fair among many fishermen and other community members. No privieged cass of obster fishermen is created by the pan and there are no haves and have-nots created. A who want to enter the fishery may do so, and they compete on a eve paying fied with others in the fishery. If the open access is perceived a threat for the sustainabiity of resources or if the fishermen do not support the measure as the vaue of their icense (when it is introduced in India) wi be reduced, then the quota system shoud be continued and rights to transfer of icenses shoud aso be permitted in order to ensure socia harmony. Administrative Consequences: Administrative consequences incude changes in the amount of enforcement resources and associated costs; compiance and enforcement probems; industry acceptance and cooperation or resistance; information demands; costs of monitoring resources and research requirements; and data degradation incuding misreporting of andings and fishing activities. Administrative consequences aso incude the extent to which obster fishermen encourage their representatives to become invoved in the impementation of management measures. Such infuences are we known for their abiity to thwart the abiity of fishery management authorities to effectivey manage the fisheries for which they are responsibe. The administration, during the initia stages of the management pan faces rising costs on one side and resistance from the other. Apart from costs incurred on research, data coection and estabishing conservation measures, the authorities need funds to communicate the importance of such measures to the fishermen and educate them as to why such measures are required. It is very important that any fishery management pan requires support from its main stakehoders that is the fishermen. Without their active participation and their whoehearted support, any management pan is ikey to fai. It is a fact that effective administration and enforcement means a substantia cost to the administrative authority. But it shoud be perceived, as a socia investment in the interest of the nation and the government shoud not have reservations over such an approach. In the ong term, a we managed industry shoud become sef-financing through increased production and tax revenues which can support management costs. Some of the best exampes are the various Austraian Spiny Lobster Industry Management Pans (Victorian, Tasmanian, South Austraia etc), Cuban and the Rhode Isand Lobster Management Pan (USA). The respective administrations initiay spent substantia sums on research and data coection before arriving at a comprehensive management pan. They continue to incur costs on research, surveiance and enforcement (athough these costs are recovered from the industry 14 15