Upstream Behavior of Glass Eels (Anguilla japonica) in an Experimental Eel-ladder

실험 어도에서 실뱀장어의 소상 행동

  • Hwang, Sun-Do (West Sea Fisheries Research Institute, National Fisheries Research and Development Institute) ;
  • Lee, Tae Won (Department of Oceanography, Chungnam National University) ;
  • Hwang, Hak-Bin (Department of Oceanography, Chungnam National University) ;
  • Choi, Il-Su (Department of Applied Mathematics, Chonnam National University) ;
  • Hwang, Sun Jae (Fisheries Resources Research Division, National Fisheries Research and Development Institute)
  • 황선도 (국립수산과학원 서해수산연구소) ;
  • 이태원 (충남대학교 해양학과) ;
  • 황학빈 (충남대학교 해양학과) ;
  • 최일수 (전남대학교 응용수학과) ;
  • 황선재 (국립수산과학원 자원연구과)
  • Received : 2009.11.16
  • Accepted : 2009.12.23
  • Published : 2009.12.31

Abstract

Upstream behavior of glass eels was examined in an experimental eel-ladder at a laboratory of the National Fisheries Research and Development Institute from March to May in 2008. The study was made under various environmental factors and conditions affecting the upstream migration of glass eels in order to design a functional ladder that would allow the passage of glass eels. The experimental eel-ladder consisted of an upper freshwater chamber and a lower sea water chamber; glass eels in sea water can move up to the upper freshwater chamber through the slope (eel-ladder) between them. The optimal condition of the eel-ladder was estimated by comparing the number of glass eels that moved upstream depending on various conditions. Since the glass eels actively moved up the slope to river water rather than to reservoir water or tap water, the experiment was realized using river water. A significantly higher number of glass eels moved up during the spring tide than during the neap tide, and during night than during the day. Upstream movement was significantly higher during high tide than during low tide. Glass eels effectively moved up through a slope of less than $30^{\circ}$ and water-flow velocity lower than 0.4 m/sec. The fish preferred a coarser ladder bed covered with small gravels, brush or carpet.

실뱀장어용 생태 어도를 설계하기 위하여 2008년 실뱀장어 소상 시기인 3~5월에 국립수산과학원 어군행동실험실에 실뱀장어가 소상하는 하구 및 하구둑과 어도를 재현하는 모형 어도를 제작하여 다양한 소상 환경과 어도 조건에서 실뱀장어의 소상행동을 관찰 분석하였다. 아래 해수조에 순치한 실뱀장어를 두고 위 담수조의 담수를 아래로 흐르게 하면서 해수조에서 어도를 통해 담수조로 소상한 실뱀장어의 개체수를 비교하고, 실뱀장어의 소상 행동을 관찰하여 최적 소상을 위한 적정 어도 조건을 추정하였다. 실뱀장어는 수돗물로는 소상하지 않았고, 저수지물보다 강물을 선호하였다. 실뱀장어 소상량은 소조기보다 대조기에 유의하게 많았고(p<0.05), 낮보다 밤에 유의하게 많았다(p<0.05). 실뱀장어 소상량은 저조위보다 고조위에서 유의하게 많았다 (p<0.05). 실뱀장어는 어도 경사면 길이가 짧을수록 소상량이 많았고, 경사도는 $30^{\circ}$ 이하가 효율적이었다 (p<0.05). 유속은 0.4 m/sec 이하로 물이 약하게 흐를 때 소상량이 많았다(p<0.05). 어도의 바닥은 솔, 자갈 및 카펫 등과 같이 거친 재질에서 소상량이 유의하게 많았다(p<0.05).

Keywords

Acknowledgement

Grant : 하구역에서의 뱀장어 생태와 어도 개선 방안-뱀장어 어도 설계를 위한 소상 행동 연구

Supported by : 한국해양수산기술진흥원

References

  1. 김을배. 1974. 제주도산 실뱀장어의 소상 동태에 관하 연구: 특히 환경요인과의 관계를 중심으로. 한국육수학회지, 7: 1-22.
  2. 문형태. 2002. 실뱀장어 이석의 미세구조와 어획 자료를 이용한 뱀장어 Anguilla jpaonica의 초기 생활사. 충남대학교 대학원 박사학위논문, 111pp.
  3. 양홍준∙김구환∙금지돈. 2001. 낙동강하구의 어류상과 댐의 어도에서 어류의 이동. 한국육수학회지, 34: 251-258.
  4. 전승관∙주광현∙주태근. 1971. 뱀장어 양식시험. 국립수산진흥원 사업보고(담수양식) 제8호, 국립수산진흥원, 부산, pp. 7-36.
  5. 이태원. 2003. 실뱀장어 자원 예측을 위한 뱀장어 초기 생활사와 소상 생태 연구. 수산특정연구과제최종보고서(과제번호:20000137), 85pp.
  6. 황종서. 2000. 농업기반시설의 어도설치 현황과 개선 방안. 한국수자원학회지, 33: 41-52.
  7. 황종서. 2003. 댐의 어도 설치 현황과 개선방안. 한국환경생태학회 2003년도 추계학술논문발표회 논문집, pp. 73-104.
  8. Aida, K., K. Tsukamoto and K. Yamauchi. 2003. Eel Biology. Springer-Verlag, Tokyo, 497pp.
  9. Briand, C., D. Fatin, G. Fontenelle and E. Feunteun. 2005. Effect of re-opening of a migratory pathway for eel (Anguilla anguilla, L.) at a watershed scale. Bull. Fr. Peche Piscic., 378-379:67-86.
  10. Cheng, P.W. and W.N. Tzeng. 1996. Timing of metamorphosis and estuarine arrival across the dispersal range of the Japanese eel Anguilla japonica. Mar. Ecol. Prog. Ser., 131: 87-96. https://doi.org/10.3354/meps131087
  11. Chow, S., H. Kurogi, N. Mochioka, S. Kaji, M. Okazaki and K. Tsukamoto. 2009. Discovery of mature freshwater eels in the open ocean. Fish. Sci., 75: 257-259. https://doi.org/10.1007/s12562-008-0017-5
  12. Deelder, C.L. 1970. Synopsis of biological data on the eel Anguilla anguilla (Linnaeus) 1758, Rome. 68pp.
  13. Dekker, W. 2003. Worldwide decline of eel resources necessitates immediate action-Quebec Declaration of Concern. Fisheries, 28: 28-30.
  14. Fontenelle, G., C. Briand and E. Feunteun. 2001. Eel management in France: how are we to face the dilemma of a European wide species?. J. Taiwan Fish. Res., 9: 237-250.
  15. http://www.nypa.gov/press/2005//050902bpr.htm
  16. http://www.fish-pass.fr
  17. Kim, D.J., J.Y. Bae and E.O. Kim. 2007. Changes in sex steroid hormones and ovarian development during artificial maturation of female eel, Anguilla japonica. Integrative Bioscience, 11: 117-124. https://doi.org/10.1080/17386357.2007.9647323
  18. Kim, W.S., S.J. Yoon., H.T. Moon. and T.W. Lee. 2002. Effects of water temperature changes on the endogenous and exogenous rhythm of oxygen consumption in the glass eels Anguilla japonica. Marine Ecology Progress Series, 243: 209-216. https://doi.org/10.3354/meps243209
  19. Kim, W.S., S.J. Yoon., J.W. Kim., J.A. Lee and T.W. Lee. 2006. Metabolic response under different salinity and temperature conditions for glass eel Anguilla japonica, Marine Biology, 149: 1209-1215. https://doi.org/10.1007/s00227-006-0293-5
  20. Liew, P.K.L. 1982. Impact of the eel ladder on the upstream migrating eel (Anguilla rostrata) population in the St. Lawrence River at Cornwall: 1974-1978. In: Loftus, K.H. (ed.), Proc 1980 N. Am. Eel Conf. Ontario Fish. Tech. Rep. Ser., Vol. 4. Ministry of Natural Resources, Ontario, pp. 17-22.
  21. SAS. 1989. SAS/STAT User’s Guide. Ver. 6. Cary. NC, SAS Institute Inc.
  22. Tanaka, H. 1999. Early life history of artificial hatching eel. In: Symposium on ‘The present state of fishery management and conservation strategies for a population of the Japanese eel, Anguilla japonica.’ Ocean Res. Inst., Univ. of Tokyo. Sept, 1999.
  23. Tanaka, H. 2001. Larval rearing and development. In: Proceedings of the International Symposium on advances in Eel Biology. Univ. of Tokyo. Sept. 28-30, pp. 89-91.
  24. Tanaka, H., H. Kagawa and H. Ohta. 2001. Production of leptocephali of japanese eel, Anguilla japonica in captivity. Aquaculture, 201: 51-60. https://doi.org/10.1016/S0044-8486(01)00553-1
  25. Tesch, F.-W. 2003. The Eel (3rd edition). Blackwell Science, Iowa. 408pp.
  26. Tsukamoto, K. 1990. Recruitment mechanism of the eel, Anguilla japonica, to the Japanese coast. J. Fish Biol, 36: 659-671. https://doi.org/10.1111/j.1095-8649.1990.tb04320.x
  27. Tsukamoto, K., T. Otake, N. Mochioka, T.-W. Lee, H. Fricke, T. Inagaki, J. Aoyama, S. Ishikawa, S. Kimura, M.J. Miller, H. Hasumoto, M. Oya and Y. Suzuki. 2003. Seamounts, new moon and eel spawning: The search for the spawning site of the Japanese eel. Environ. Biol. Fish., 66: 221-229. https://doi.org/10.1023/A:1023926705906
  28. Tzeng, W.N. 1985. Immigration timing and activity rhythms of the eel, Anguilla japonica, elvers in the estuary of northern Taiwan, with emphasis on environmental influences. Bull. Jap. Soc. Fish. Oceanogr., No. 47/48: 11-27.
  29. Watanabe, S., J. Aoyama and K. Tsukamoto. 2004. Reexamination of Ege's (1939) use of taxonomic characters of the genus Anguilla. Bull. Mar. Sci., 74: 337-351.
  30. Watanabe, S., J. Aoyama and K. Tsukamoto. 2009. A new species of freshwater eel Anguilla luzonensis (Teleostei: Anguillidae) from Luzon Island of the Philippines. Fish. Sci., 75: 387-392. https://doi.org/10.1007/s12562-009-0087-z
  31. Yamamoto, K. and K. Yamauchi. 1974. Sexual maturation of Japanese eel and production of eel larvae in the aquarium. Nature, 251: 220-222. https://doi.org/10.1038/251220a0
  32. Yamauchi, K., M. Nakamura, H. Takahashi and K. Takano. 1976. Cultivation of larvae of Japanese eel. Nature, 263: 412.