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Fisheries Science

, Volume 73, Issue 3, pp 477–488 | Cite as

Size selectivity of escape holes in conger tube traps for inshore hagfish Eptatretus burgeri and white-spotted conger Conger myriaster in Tokyo Bay

  • Mami Harada
  • Tadashi TokaiEmail author
  • Michiyo Kimura
  • Fuxiang Hu
  • Takamichi Shimizu
Article

Abstract

In Tokyo Bay, conger tube-trap fishers voluntarily deployed escape holes of at least 13 mm diameter to reduce the by-catch of young conger smaller than the marketable size of 35 cm total length. Comparative fishing experiments in Tokyo Bay were carried out using tube traps with seven hole diameters (3, 9, 13.5, 14, 15, 17, and 19 mm), to obtain the size-selectivity of the escape-hole size for inshore hagfish Eptatretus burgeri and white-spotted conger Conger myriaster. On the assumption of the geometrical similarity in the combination of body g and hole perimeter m at a given retention probability, a single master curve s(R)=exp(−13.52+11.31R)/(1+exp[−13.52+11.31R]) was estimated for the two species in terms of relative R=g/m using the Share Each LEngth’s Catch Total (SELECT) process based on a multinomial distribution. Almost all conger and hagfish with a girth equivalent to the hole perimeter were able to pass through the hole. Thus, the two species have a high ability to escape through a narrow space by squeezing the body through the hole in the rigid PVC tube. Optimum escape-hole size is discussed from several objectives for conger tube-trap fishery management, e.g. reduction of hagfish by-catch. This study also specifies the conditions for pooling data when fishing experiments using more than two fishing gears are replicated.

Key Words

Conger myriaster Eptatretus burgeri escape hole multinomial distribution SELECT model size selectivity tube trap 

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References

  1. 1.
    Jeong E-C, Kim S-K, Park C-D, Shin J-K, Tokai T. Size-selectivity of hole on tubular-pot for white spotted conger eel Conger myriaster in the adjacent Sea of Korea. Nippon Suisan Gakkaishi 1999; 65: 260–267.Google Scholar
  2. 2.
    Shimizu T. On the resource of white-spotted conger Astroconger myriaster (Brevoort) in Tokyo Bay-II Estimation of the escapement curve from draining halls. Bull. Kanagawa Pref. Fish. Res. Inst. 1997; 2: 1–5.Google Scholar
  3. 3.
    Shimizu T. On the resource of white-spotted conger, Conger myriaster (Brevoort) in Tokyo Bay-III Examination for determining optimum size of draining halls. Bull. Kanagawa Pref. Fish. Res. Inst. 1999; 4: 15–18.Google Scholar
  4. 4.
    Tokai T, Shimizu T, Nakagawa T, Saita Y. Implementation process of enlarged escape-holes to conger tube fishery in Tokyo Bay. Fish. Sci. 2002; 68 (Suppl. 1): 467–468.Google Scholar
  5. 5.
    Shimizu T. On the resource of white-spotted conger Conger myriaster in Tokyo Bay. Bull. Kanagawa Pref. Fish. Res. Inst. 2003; 8: 1–11.Google Scholar
  6. 6.
    Gorbman A, Kobayashi H, Honma Y, Matsuyama M. The hagfish of Japan. Fisheries 1990; 15: 12–18.CrossRefGoogle Scholar
  7. 7.
    Martini FH. The ecology of hagfish. In: Jorgensen JM, Lomholt JP, Weber RE, Malte H (eds). The Biology of Hagfishes. Chapman & Hall, London. 1998; 57–77.Google Scholar
  8. 8.
    Powell ML, Kavanaugh SI, Sower SA. Current knowledge of hagfish reproduction: implications for fisheries management. Integr. Comp. Biol. 2005; 45: 158–165.CrossRefGoogle Scholar
  9. 9.
    Barss WH. Pacific hagfish, Eptatretus stouti, and black hagfish, E. deani: the Oregon fishery and port sampling observations, 1988–1992. Mar. Fish. Rev. 1993; 55: 19–30.Google Scholar
  10. 10.
    Ichikawa T, Kobayashi H, Nozaki M. Seasonal migration of the hagfish, Eptatretus burgeri, Girard. Zool. Sci. 2000; 17: 217–223.CrossRefGoogle Scholar
  11. 11.
    Nozaki M, Ichikawa T, Tsuneki K, Kobayashi H. Seasonal development of gonadal of the hagfish Eptatretus burgeri, correlated with their seasonal migration. Zool. Sci. 2000; 17: 225–232.CrossRefGoogle Scholar
  12. 12.
    Harada M, Tokai T, Uchida K, Shimizu T. Distribution of white-spotted conger eel Conger myriaster and hagfish Eptatretus burgeri at shallow region in Tokyo Bay. Nippon Suisan Gakkaishi 2006; 72: 894–904.CrossRefGoogle Scholar
  13. 13.
    Millar RB. Estimating the size-selectivity of fishing gear by conditioning on the total catch. J. Am. Stat. Assoc. 1992; 87: 962–968.CrossRefGoogle Scholar
  14. 14.
    Wilemann DA, Ferro RST, Fonteyne R, Millar RB. Manual of methods of measuring the selectivity of towed fishing gears. ICES Coop. Res. Rep. 1996; 125: 1–126.Google Scholar
  15. 15.
    Xu X, Millar RB. Estimation of trap selectivity for male snow crab (Chionoecetes opilio) and using the SELECT modeling approach with unequal sampling effort. Can. J. Fish. Aquat. Sci. 1993; 50: 2485–2490.CrossRefGoogle Scholar
  16. 16.
    Tokai T, Mituhashi T. Select model for estimating selectivity curve from comparative fishing experiments. Bull. Jpn. Soc. Fish. Oceanogr. 1998; 62: 235–247.Google Scholar
  17. 17.
    Millar RB, Fryer RJ. Estimating the size-selection curves of towed gears, traps, nets and hooks. Rev. Fish Biol. Fish 1999; 9: 89–116.CrossRefGoogle Scholar
  18. 18.
    Uchida K, Tokai T, Mituhashi T, Hu F, Matuda K. Size selectivity of net-pot for white-spotted conger eel estimated from paired-gear tests with change in sampling effort. Nippon Suisan Gakkaishi 2000; 66: 228–235.Google Scholar
  19. 19.
    Fujimori Y, Tokai T. Estimation of gillnet selectivity curve by maximum likelihood method. Fish. Sci. 2001; 67: 644–654.CrossRefGoogle Scholar
  20. 20.
    Nishiuchi S. A study on size-selectivity of hair crab pots. Sci. Rep. Hokkaido Fish. Exp. Stn. 2003; 64: 1–103.Google Scholar
  21. 21.
    Tokai T, Omoto S, Matuda K. Mesh selectivity of unmarketable trash fish by a small trawl fishery in the Seto Inland Sea. Nippon Suisan Gakkaishi 1994; 60: 347–352.Google Scholar
  22. 22.
    Tokai T. Method of determining mesh-selectivity curve of trawl and its application to fisheries management. Nippon Suisan Gakkaishi 1998; 64: 597–600.Google Scholar
  23. 23.
    Tokai T. Maximum likelihood parameter estimates of a mesh selectivity logistic model through SOLVER on MS-Excel. Bull. Jpn. Soc. Fish. Oceanogr. 1997; 61: 288–298.Google Scholar
  24. 24.
    Omoto S, Tokai T, Tanda M, Nishikawa T, Matuda K. Comparison of selectivity curve between square-mesh and diamond-mesh codends by AIC. Nippon Suisan Gakkaishi 1998; 64: 447–452.Google Scholar
  25. 25.
    Yokota K, Fujimori Y, Shiode D, Tokai T. Effect of thin twine on gill net size-selectivity analyzed with the direct estimation method. Fish. Sci. 2001; 67: 851–856.CrossRefGoogle Scholar
  26. 26.
    Uchida K, Arai N, Moriya K, Miyamoto Y, Kakihara T, Tokai T. Development of automatic system for monitoring fishing effort in conger-eel tube fishery using radio frequency identification and global positioning system. Fish. Sci. 2005; 71: 992–1002.CrossRefGoogle Scholar
  27. 27.
    Treble RJ, Millar RB, Walker TL. Size-selectivity of lobster pot with escape-gaps: application of the SELECT method to the southern rock lobster (Jasus edwardsii) fishery in Victoria, Australia. Fish Res. 1998; 34: 289–305.CrossRefGoogle Scholar
  28. 28.
    Nishikawa T, Tanda M, Nagahama T, Tokai T. Mesh selectivity of small trawl for white-spotted conger in Osaka Bay. Nippon Suisan Gakkaishi 1994; 60: 735–739.Google Scholar
  29. 29.
    Uchida K, Tokai T, Hu F, Matuda K. Mesh selectivity of net pot for white-spotted conger eel estimated from a cover-net fishing experiment. Nippon Suisan Gakkaishi 1998; 64: 815–821.Google Scholar
  30. 30.
    Liang Z, Horikawa H, Tokimura M, Tokai T. Effect of cross-sectional shape of fish body on mesh selectivity of trawl codend. Nippon Suisan Gakkaishi 1999; 65: 441–447.Google Scholar
  31. 31.
    Shepherd GR, Moore CW, Seagraves RJ. The effect of escape vents on the capture of black sea bass, Centropristis striata, in fish traps. Fish. Res. 2002; 54: 195–207.CrossRefGoogle Scholar
  32. 32.
    Carlile DW, Dinnocenzo TA, Watson LJ. Evaluation of modified crab pots to increase catch of Pacific cod and decrease bycatch of Pacific halibut. North Am. J. Fish. Manag. 1997; 17: 910–928.CrossRefGoogle Scholar
  33. 33.
    Shephard S, Jackson DC. Size selection of channel catfish in slat traps of different interslat space widths. Trans. Am. Fish. Soc. 2004; 133: 197–203.CrossRefGoogle Scholar
  34. 34.
    King JR, McFarlane GA. Marine fish life history strategies: applications to fishery management. Fish. Manage. Ecol. 2003; 10: 249–264.CrossRefGoogle Scholar
  35. 35.
    Yuki Y, Ishida K, Yasugi S. The ecology of hagfish Eptatretus burgeri and the fisheries actual condition in the Japan Sea off Shimane Prefecture. Bull. Shimane Pref. Fish. Expl. Stn. 2003; 11: 1–6.Google Scholar

Copyright information

© The Japanese Society of Fisheries Science 2007

Authors and Affiliations

  • Mami Harada
    • 1
  • Tadashi Tokai
    • 1
    Email author
  • Michiyo Kimura
    • 1
  • Fuxiang Hu
    • 1
  • Takamichi Shimizu
    • 2
  1. 1.Faculty of Marine ScienceTokyo University of Marine Science and TechnologyMinato, TokyoJapan
  2. 2.Kanagawa Prefectural Fisheries Technology CenterMiura City, KanagawaJapan

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