MEPS

Marine Ecology Progress Series

MEPS is a leading hybrid research journal on all aspects of marine, coastal and estuarine ecology. Priority is given to outstanding research that advances our ecological understanding.

Online: ISSN 1616-1599

Print: ISSN 0171-8630

DOI: https://doi.org/10.3354/meps

Impact Factor2.1 (JCR 2025 release)

Article Acceptance Rate52.2% (2024)

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Volume contents
Mar Ecol Prog Ser 662:125-138 (2021)

Differences in the reproductive traits of Pacific bluefin tuna Thunnus orientalis among three fishing grounds in the Sea of Japan

ABSTRACT: Differences in the reproductive traits of Pacific bluefin tuna Thunnus orientalis (PBF) in the Sea of Japan (SOJ) were investigated to evaluate the reproductive potential in 3 fishing grounds (i.e. northern, central and southern areas). The size distribution of PBF differed among the fishing grounds, with smaller fish (100-130 cm in fork length, FL) being caught in the central and northern areas of the SOJ. Spawning-capable females were found at sea surface temperatures (SSTs) between 17 and 25°C, with most SSTs >21°C. Seasonal changes in SST differed among the fishing grounds, and the period when SST exceeded 21°C differed in each fishing ground. Spawning-capable females were found at different times among the fishing grounds, and were observed throughout the fishing season in the southern area of the SOJ. The mean ± SD relative batch fecundity was estimated to be 69.8 ± 45.3 and 92.7 ± 43.1 oocytes g-1 in the central and southern areas of the SOJ, respectively. The total spawning fraction was 0.2, 0.38 and 0.73 in the northern, central and southern areas of the SOJ, respectively. SST and FL were positively correlated with the batch fecundity. In addition, FL, SST and location affected the probability of occurrence of spawning-capable fish among mature fish. Therefore, the difference in the observed reproductive potential of PBF among fishing grounds in the SOJ can be linked to the differences in seasonal increases in SST and the size distribution of adult fish.

KEYWORDS

Hiroshi Ashida (Corresponding Author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan
hashida@affrc.go.jp

Yumi Okochi (Co-author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan
  • Environmental management unit, JAPAN NUS Co. Ltd, Shinjuku-ku, Tokyo, 160-0023 Japan

Seiji Ohshimo (Co-author)

  • Nagasaki Field station, Fisheries Resources Institute, Japan Fisheries Research and Education Agency, Nagasaki, Nagasaki 851-2213, Japan

Takuya Sato (Co-author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan

Yukio Ishihara (Co-author)

  • Tottori Prefectural Fisheries Experimental Station, Sakai-Minato, Tottori 684-0046, Japan

Shuuyo Watanabe (Co-author)

  • Tottori Prefectural Fisheries Experimental Station, Sakai-Minato, Tottori 684-0046, Japan

Ko Fujioka (Co-author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan

Seishiro Furukawa (Co-author)

  • Niigata Field station, Fisheries Resources Institute, Fisheries Research and Education Agency, Niigata, Niigata 961-8121, Japan

Tomonori Kuwahara (Co-author)

  • Environmental management unit, JAPAN NUS Co. Ltd, Shinjuku-ku, Tokyo, 160-0023 Japan

Yuko Hiraoka (Co-author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan

Yosuke Tanaka (Co-author)

  • Shimizu Field station, Fisheries Recourses Institute, Japan Fisheries Research and Education Agency, Shimizu, Shizuoka 424-8633, Japan