Fisheries Science

, Volume 77, Issue 2, pp 161–167 | Cite as

Swimming angle and target strength of larval Japanese anchovy (Engraulis japonicus)

  • Yusuke Ito
  • Hiroki Yasuma
  • Reiji Masuda
  • Kenji Minami
  • Ryuichi Matsukura
  • Saho Morioka
  • Kazushi Miyashita
Original Article Fisheries

Abstract

The swimming angle of larval Japanese anchovy (Engraulis japonicus) was measured in a tank, and target strength (TS) was calculated using a theoretical scattering model. The mean swimming angle was 12.8° (SD ±22.1). Increased speeds of flow led to increased mean swimming angles. The mean swimming angle at flow of 5 cm s−1 was higher than at other speeds. TS values were estimated using a distorted-wave Born approximation model for two cases. Average values were 1–3 cm s−1 (11.5° ± 22.1) and 5 cm s−1 (16.6° ± 21.7) for cases 1 and 2, respectively. For case 1, TS ranged from −92.0 to −74.7 dB with a mean of −79.4 dB at 120 kHz. For case 2, TS ranged from −92.2 to −75.2 dB with a mean of −79.9 dB. The mean TS in case 2 was lower than that in case 1, with the maximum difference being 1.0 dB at 120 kHz (standard length 22.0 mm). However, there were no significant differences between the regression lines of cases 1 and 2. Thus, changes in flow speed altered the swimming angle of larval Japanese anchovy, but had little influence on TS.

Keywords

Larval Japanese anchovy Swimming angle Target strength 

Notes

Acknowledgments

We thank the captains and crew of Kanagasaki Maru No. 8 for their cooperation in collecting specimens. We also thank Yukio Ueta, Keisuke Mori Fisheries Research Institute, Tokushima Agriculture and the Forestry and Fisheries Technology Support Center for their support in collecting specimens. This study was supported in part by the Fisheries Agency of Japan under the project “Research and Development Projects for Application in Promoting New Policy of Agriculture Forestry and Fisheries.” We thank this institution for their support.

References

  1. 1.
    Annual Statistics on Fishery and Aquaculture Production 2006 (2008) Statistics Department, Ministry of Agriculture, Forestry and Fisheries, TokyoGoogle Scholar
  2. 2.
    Saiura K, Takeda Y (2001) Spring fishing ground formation of anchovy, Engraulis japonica, larvae in 1999 and 2000 in the Kii Channel (in Japanese). Fish Biol Oceanogr Kuroshio 2:109–118Google Scholar
  3. 3.
    Morioka S (2006) Trial of spring shirasu (Engraulis japonicus larvae) fishery forecast in Kii Channel by using multiple regression analysis (in Japanese). Fish Biol Oceanogr Kuroshio 7:21–27Google Scholar
  4. 4.
    Mitani I (1988) The biological studies on the larvae of Japanese anchovy, Engraulis japonica Hottuyn, in Sagami Bay (in Japanese). PhD thesis, University of Hokkaido, HokkaidoGoogle Scholar
  5. 5.
    Honda S (2004) Abundance estimation of the young cohorts of the Japanese Pacific population of walleye pollock (Theragra chalcogramma) by acoustic surveys (In Japanese). PhD thesis, University of Hokkaido, HokkaidoGoogle Scholar
  6. 6.
    Yasuma H (2004) Studies on the acoustical biomass estimation of myctophid fishes (in Japanese). PhD thesis, University of Tokyo, TokyoGoogle Scholar
  7. 7.
    Zhao X, Wang Y, Dai F (2008) Depth-dependent target strength of anchovy (Engraulis japonicus) measured in situ. ICES J Mar Sci 65:882–888CrossRefGoogle Scholar
  8. 8.
    Foote KG, Traynor JJ (1988) Comparison of walleye pollock target-strength estimates determined from in situ measurements and calculations based on swimbladder form. J Acoust Soc Am 83(1):9–17CrossRefGoogle Scholar
  9. 9.
    Simmonds J, MacKennan D (2005) Fisheries acoustics, 2nd edn. Blackwell, OxfordCrossRefGoogle Scholar
  10. 10.
    Uotani I (1973) Diurnal changes of gas bladder and behavior of postlarval anchovy and other related species (in Japanese with English abstract). Bull Jpn Soc Sci Fish 39:867–876Google Scholar
  11. 11.
    Miyashita K (2003) Diurnal changes in the acoustic-frequency characteristics of Japanese anchovy (Engraulis japonicus) post-larvae “shirasu” inferred from theoretical scattering models. ICES J Mar Sci 60:532–537CrossRefGoogle Scholar
  12. 12.
    Stanton TK, Chu D, Wiebe PH (1993) Sound scattering by several zooplankton groups. II. Scattering models. J Acoust Soc Am 103:236–253CrossRefGoogle Scholar
  13. 13.
    Chu D, Foote KG, Stanton TK (1993) Further analysis of target strength measurements of Antarctic krill at 38 and 120 kHz: comparison with deformed cylinder model and inference of orientation. J Acoust Soc Am 93:2985–2988CrossRefGoogle Scholar
  14. 14.
    McGehee DE, O’Driscoll RL, Martin Traykovdky LV (1998) Effects of orientation on acoustic scattering from Antarctic krill at 120 kHz. Deep-Sea Res 45:1273–1394CrossRefGoogle Scholar
  15. 15.
    Foote KG (1980) Averaging of fish target strength functions. J Acoust Soc Am 67(2):504–515CrossRefGoogle Scholar
  16. 16.
    Foote KG (1990) Speed of sound in Euphausia superba. J Acoust Soc Am 87:1405–1408CrossRefGoogle Scholar
  17. 17.
    Greenlaw CF (1977) Backscattering spectra of preserved zooplankton. J Acoust Soc Am 62:44–52CrossRefGoogle Scholar
  18. 18.
    Foote KG (1979) On representing the length dependence of acoustic target strengths of fish. J Fish Res Board Can 36(12):1490–1496Google Scholar
  19. 19.
    Hunter JR (1972) Swimming and feeding behavior of larval anchovy, Engrauis mordax. Fish Bull 70:821–838Google Scholar
  20. 20.
    Batty RS (1984) Development of swimming movements and musculature of larval herring (Clupea harengus). J Exp Biol 110:217–229PubMedGoogle Scholar
  21. 21.
    Blaxter JHS, Staines ME (1971) Food searching potential in marine fish larvae. Fourth European marine biological symposium. Cambridge University Press, CambridgeGoogle Scholar
  22. 22.
    Mikami H, Mukai T, Iida K (2000) Measurements of density and sound speed contrasts for estimating krill target strength using theoretical scattering models (in Japanese with English abstract). Nippon Suisan Gakkaishi 66(4):682–689Google Scholar
  23. 23.
    Matsukura R, Yasuma H, Murase H, Yonezak S, Funamoto T, Honda S, Miyashita K (2009) Measurement of density contrast and sound-speed contrast for target strength estimation of Neocalanus copepods (Neocalanus cristatus and Neocalanus plumchrus) in the North Pacific Ocean. Fish Sci 75:1377–1387CrossRefGoogle Scholar

Copyright information

© The Japanese Society of Fisheries Science 2011

Authors and Affiliations

  • Yusuke Ito
    • 1
  • Hiroki Yasuma
    • 2
  • Reiji Masuda
    • 3
  • Kenji Minami
    • 3
  • Ryuichi Matsukura
    • 4
  • Saho Morioka
    • 5
  • Kazushi Miyashita
    • 2
  1. 1.Laboratory of Marine Ecosystem Change Analysis, Graduate School of Environmental ScienceHokkaido UniversityHakodateJapan
  2. 2.Laboratory of Marine Ecosystem Change Analysis, Field Science Center for Northern BiosphereHokkaido UniversityHakodateJapan
  3. 3.Fisheries Research StationKyoto UniversityMaizuruJapan
  4. 4.National Research Institute of Fisheries Engineering, FRAKamisuJapan
  5. 5.Fisheries Research InstituteTokushima Agriculture, Forestry and Fisheries Technology Support CenterTokushimaJapan

Personalised recommendations