Universities Research Journal 2011, Vol. 4, No. 2 Species Composition and Seasonal Occurrence of Fish Fauna in Lay-Ein-Su-Let-Kyar In, Myingyan Township, Mandalay Region Htay Htay Sein Abstract Species composition and seasonal occurrence of fish fauna in Lay-Ein- Su-Let-Kyar In, Myingyan Towship, Mandalay Region was investigated from January 2007 to December 2008. Forty three species belonging to 30 genera, 19 families and 7 orders were recorded in this work. Fish species of the order Cypriniformes predominate in the study area with percent composition of 34.88. The highest number of fish species (43) was recorded during July and August. The number of species (43) was found to be highest during rainy season, followed by (42) during cold season and (41) during the hot season. Key words: Species composition, seasonal occurrence, fish,lay-ein-su- Let-Kyar In Introduction Four main river systems in Myanmar flow from the north to south, crossing the main land of the country. The Ayeyarwady River and its floodplains are important aquatic resources in Myanmar. The floodplain lakes of the Ayeyarwady River are highly productive and play an important role in the ecology of the rivers system. Lay-Ein-Su- Let-Kyar In is a seasonally flooded area in Myingyan Township, Mandalay Region. Water enters into the lake from swollen Ayeyarwady River during the rainy season. The water level in the lake recedes with river water at later part of the season. The riverine fishes, especially spawners were left behind in the lake. Water remains through cold and hot seasons and thus forms a habitat of the fish fauna. Lay-Ein-Su-Let-Kyar In often acts as a center for reproduction and production of commercially important fish species. So the fishery works of this lake is continuous throughout the year. Fish production and resilience to exploitation is generally higher on the floodplain than within more stable environments (Lowe-Mc Connell, 1987). The floodplain environment also promotes species diversity due to its dynamic habitat structure (Junk et al., 1989). Associate Professor, Dr., Zoology Department, University of Mandalay
38 Universities Research Journal 2011, Vol. 4, No. 2 Understanding the role of floodplain lake for the productivity of fish, composition and seasonal occurrence of fish species were investigated in Lay-Ein-Su-Let-Kyar In, Myingyan Township. Materials and Methods Study area The study area Lay-Ein-Su-Let-Kyar In is situated near the Lay-Ein- Tan Village, Myingyan Township, Mandalay Region. The study area is located between 21 26'31.077'' and 21 28'31.970'' N Latitudes and between 95 20'25.846'' and 95 21'51.375'' E Longitudes. It extends approximately 5.12 km from north to south and 1 km from east to west, occupying an area of 239 hectares. The study area was divided into three sampling sites. The first sampling site was the northern part of the lake directly connected with Ayeyarwady, (the area between starting point of lake and Lay Ein Tan Village), the second site was the middle portion of the lake (the area between Lay Ein Tan Village and Hlaing Tet Village) and the third sample site was the southern part of the lake (the area between Hlaing Tet Village and Aye Ywa Village) (Fig. 1). Study period The field survey and specimen collections were carried out from January 2007 to December 2008. Collection and preservation Collection of specimens was made at all three sampling sites. The physical appearance of fish was noted down and the photo was also taken immediately after capturing the fish. Small specimens were preserved in 10% formalin and then transferred to 5% formalin. The medium and large specimens were injected with 10% formalin into the abdominal cavity for total fixation. Fish were caught using single fishing gear (cast net) in all three sampling sites to determine the species composition, and seasonal occurrence. Same frequency of catch or trap rate e.g., 10 times per site per trip was maintained throughout the study period. Collection was made twice per month.
Universities Research Journal 2011, Vol. 4, No. 2 39 Identification of species Collected specimens were brought to the Department of Zoology, University of Mandalay. The preserved specimens were washed thoroughly under tap water and identified according to Day (1878, 1889), Jayaram (1981), Talwar and Jhingran (1991), Rainboth (1996) and Ferraris (1997). The classification of fishes is according to Talwar and Jhingran (1991). Presentation of data The fish species collected from three sampling sites were pooled to represent the fish species occurred in the study area. Results Species composition A total of 43 species was collected during the course of study. These fish species are confined to seven orders, 19 families and 30 genera. Among the orders, Osteoglossiformes, Cyprinodontiformes and Tetraodontiformes were each represented by a single species. Clupeiformes was confined to two species, two genera and one family while Cypriniformes was with 15 species, nine genera and three families. Siluriformes was confined to 13 species, nine genera and six families whereas Perciformes was with 10 species, seven genera and six families. The composition of recorded fish species was found to be the highest in the order Cypriniformes (34.88%), followed by Siluriformes (30.23%), Perciformes (23.25%), Clupeiformes (4.65%) and the remaining three orders, Osteoglossiformes, Cyprinodontiformes, and Tetrodontiformes (each with 2.33%) (Table 1, Fig. 2). Seasonal occurrence During the study period of January 2007 to December 2008, the numbers of species were observed to be varying with months. Based on the monthly recorded data, the highest number of fish species was found in July and August (43) while the lowest number in February and March (36). Twenty nine species were found to occur every month whereas Clupisoma prateri was observed only in six months (Table 2).
40 Universities Research Journal 2011, Vol. 4, No. 2 As regartss seasonality of fish, the highest number of species was recorded during rainy season (43 species), followed by cold season (42 species) and hot season (40 species). Thirty nine species were recorded in all seasons, while four species occurred only in two seasons (Table 2). Fig.1 Location map of Lay-Ein-Su-Let-Kyar In
Universities Research Journal 2011, Vol. 4, No. 2 41 Table 1 Species composition in different orders in the study area during January 2007 to December 2008 Sr. Order Family Genus Species Percentage 1 Osteoglossiformes 1 1 1 2.33 2 Clupeiformes 1 2 2 4.65 3 Cypriniformes 3 9 15 34.88 4 Siluriformes 6 9 13 30.23 5 Cyprinodontiformes 1 1 1 2.33 6 Perciformes 6 7 10 23.25 7 Tetraodontiformes 1 1 1 2.33 Total 19 30 43 Fig 2 Species composition in different orders in the study area during January 2007 to December 200
42 Universities Research Journal 2011, Vol. 4, No. 2 Table 2. Monthly and seasonal occurrence of fish species In Lay-Ein-Su- Let-Kyar In during January 2007 to December 2008 Hot Rainy Cold Family Species Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan 1.Notopteridae 1. Notopterus notopterus 2. Clupeidae 2. Gudusia variegate 3. Tenuolosa ilisha 3. Cyprinidae 4. Cirrhinus marigala 5.Cyprinus carpio - - 6. Labeo angra 7. L.calbasu 8. L.rohita 9. L.boga 10. Osteobrama feae - - - - 11. O.belangeri 12. Puntius sarana 13. Puntius sophore 14. P.gonionotus 15. Raiamas guttatus 16. Salmostoma sardinella 4. Cobilidae 17. Botia berdmorei - - - 5.Balitoridae 18. Nemacheilus rubidipinnis 6. Bagridae 19. Aorichthyes aor - 20. Mystus cavasius 21. M. bleekeri 22. M.pulcher 23. M.menoda - - 24. M.gulio - 7. Arridae 25. Hemipimelodus jaticus - 8.Siluridae 26. Ompok bimaculatus 27. Wallago attu 9. Schibeidae 28. Eutropiichthyes vacha - - - - 29. Clupisoma prateri - - - - - - 10. Sisoridae 30. Gagata cenia - - 11. Heteropneustidae 31. Heteropneustes fossilis - - -
Universities Research Journal 2011, Vol. 4, No. 2 43 Hot Rainy Cold Family Species Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan 12. Belonidae 32. Xenentodon cancila - - - - 13. Ambassidae 33. Pseudombasis ranga 14. Cichlidae 34. Oreochromis sp. 15. Gobiidae 35. Glossogobius giuris 16. Mugilidae 36. Rhinomugil corsula - - - - 17. Channidae 37. Channa striatus 38. C. punctatus 18.Mastacembelidae 39. Marognathus aral 40. M. zebrinus 41. Mastacembelus dayi 42. M. manipurensis 19. Tetraodontidae 43. Tetraodon cutcutia - Total species 36 36 37 39 42 43 43 42 40 40 40 40 Discussion A total of 43 freshwater fish species belonging to 30 genera under 19 families and seven orders were recorded from the study area during the period from January 2007 to December 2008. No systematic work has been done in fish species of Lay-Ein-Su-Let-Kyar In previously. The recorded species in this work belong to seven orders, Osteoglossiformes (1 species), Clupeiformes (2 species), Cypriniformes (15 species), Siluriformes (13 species), Cyprinodontiformes (1 species), Perciformes (10 species) and Tetraodontiformes (1 speices). The order Cypriniformes was predominant in the study area because the highest number of fish species belonged to that order. Then, the second predominant group was observed in order Siluriformes. The above finding is in agreement with that of Lagler et al. (1962) who reported that cyprinids are the major freshwater fish group and thus become conspicuous parts of the fauna in different streams and lakes. About one-third of all freshwater fishes in western Borneo were represented by cyprinids (Roberts, 1989). Nyanti (1995) and Leh (2000) reported that approximately 66% and 46% respectively of the fish collections in Sarawak were from the Cyprinidae family. The freshwater fish faunas of East and
44 Universities Research Journal 2011, Vol. 4, No. 2 South East Asia are dominated by cyprinids (Rainboth, 1991). Similarly, 34.88% cyprinids were dominant among the fish fauna in the study area. Regarding the order Siluriformes, although the numbers of species are less than Cypriniformes most of the members are regarded as commercially important species. Kullandar et al. (2004) described that the order Siluriformes is one of the largest order with ten families. Among them, the family Bagridae consists of a diverse group of catfishes which are considered as most commercially important for food consumption and aquarium trade. Jayaram (1981) also stated that catfishes of the order Bagridae are popular sport fish and valued food items inhabiting in freshwater. The seasonality of fish species was not distinctive during the study period in this work, because almost every species occurred in all seasons. In conclusion, since the reasonable number of fish occurred throughout the year, the Lay-Ein-Su-Let-Kyar In may be considered as the productive area of fish for the protein demand of people. Acknowledgements I am grateful to Rector Dr Khin Swe Myint, Pro-Rector Dr Saw Pyone Naing, University of Mandalay and Professor and Head Dr Mie Mie Sein and Professor Dr Naw Dolly Wilbur, Zoology Department, University of Mandalay for their encouragement. I also wish to express my sincere thanks to Dr Khin Maung Aye, Professor and Head (Rtd.), Zoology Department, University of Mandalay for his close supervision and suggestions. References Day, F., 1878. The fishes of Indian being a natural history of the fishes known to inhabit the sea and freshwater of India, Burma and Ceylon. Vol 1 and II. Today and Tomorrow's Book Agency, New Delhi. Day, F., 1889. The fauna of British India including Ceylon and Burma fishes. Vol. I and II, Taylor and Francis, London. 816 pp. Ferraris Jr., 1997. Identification guide to the commercial inland fishes of Myanmar. Food and Agriculture Organization of United Nations. 58 pp. Jayaram, K.C., 1981. The freshwater fish of Indian, Pakistan, Bangladesh, Burma and Sri Lanka. Zoological Survey of India, Calcutta. 475 pp. Junk, W.B.P.B., Bayley, P.B. and Spark, R.E., 1989. The flood pulse in river floodplain system. In: Proceedings of the international large River Symposium, D.P. Dudge, (ed.), pp. 110-127. Canadian Special Publication of Fisheries, Aquatic Science.
Universities Research Journal 2011, Vol. 4, No. 2 45 Kullandar, S.O., Fang, F. and Ferraric Jr.C.J., 2004. The freshwater fishes of Myanmar. Swedish Museum of Natural History (NRM). Fish Research Project. Lagler, K.F., Bardach, J.E. and Miller, R.R., 1962. The study of fishes. John Wiley and Sons. Inc., New York. 545pp. Leh, M.U.C., 2000. Fishes. In: Development of Lanjak-Entimau Wildlife Sanctuary as a Total protected Area, E. Soepadomo, and P.P.K. Chai (eds.), pp. 124-136. International Tropical Timber Organization, Japan and Sarawak Forest Department, Sarawak, Malaysia. Lowe-Mc Connell, R.H., 1987. Ecological studies in tropical fish community. Cambridge University Press, London, New York. 173 pp. Nyanti, L., 1995. Fish fauna of Sayap-Kinabalu Park, Sabah. In: A scientific journey through Borneo: Sayap-Kinabalu Park, Sabah. I. Ghazally and D. Laily (eds.), pp. 189-199. Pelanduk Publication, Kuala Lumpur. Rainboth, W.J., 1991. Cyprinids of South East Asia. In: Cyprinid fishes: Systematics, biology and exploitation. I.J. Winfield & J.S. Nelson, (eds), pp. 156-210. Chapman & Hall, London. Roberts, T.R., 1989. The freshwater fishes of Western Borneo (Kalimantan Barat, Indonesia). California Academy of Science, California. Talwar, P.K. and Jhingran, A.G., 1991. Inland fishes of India and adjacent countries. Vol. I and II. Oxford and IBH publishing Co. PVT. Ltd. New Delhi, Bombay, Calcutta. 1158pp.