- 著者
- Takumi Teraoka Kanako Amei Yutaka Fukai Kohei Matsuno Hiroji Onishi Atsushi Ooki Tetsuya Takatsu Atsushi Yamaguchi
- 出版者
- The Plankton Society of Japan, The Japanese Association of Benthology
- 雑誌
- Plankton and Benthos Research (ISSN:18808247)
- 巻号頁・発行日
- vol.17, no.4, pp.369-382, 2022-11-30 (Released:2022-11-30)
- 参考文献数
- 67
Knowledge about the taxonomic and size composition of mesozooplankton is of critical importance for both fisheries and oceanography. In this study, we collected an annual time series of mesozooplankton samples in Funka Bay and analysed them using ZooScan to reveal the seasonal changes in taxonomic and size structure. Both zooplankton abundance and biovolume peaked in April and were dominated by an appendicularian Oikopleura labradoriensis which has been reported as being are being important food source for flatfish larvae. Furthermore, Noctiluca scintillans was abundant from September to December. The occurrence of this species may be related to the recent increase in the transport of Tsugaru Warm Current water into the bay. The Normalized Biomass Size Spectra (NBSS) was significant for 16 of 21 sampling dates. Insignificant NBSS, with an extremely flat slope, was observed for January–March. Significant NBSS with a flat slope was observed in April. Then, the relatively steep slopes of the NBSS were the case from mid-May to December. These seasonal changes in the slope of NBSS suggest that the energy transfer efficiency for higher trophic levels varied seasonally. The observed slopes of the NBSS in Funka Bay ranged from −1.09 to −0.30, which was flatter than the theoretical value (−1) and the previously reported values for the oceanic region of the western North Pacific. This suggests that the energy transfer efficiency to organisms at higher trophic levels in the Funka Bay is higher than in the adjacent oceanic region.
- 著者
- Mitsuhiro Nakaya Yuhei Takeya Ryo Suzuki Kyosei Noro Weifeng Gao Tetsuya Takatsu
- 出版者
- Japanese Society for Aquaculture Science
- 雑誌
- 水産増殖 (ISSN:03714217)
- 巻号頁・発行日
- vol.65, no.3, pp.251-254, 2017-09-20 (Released:2018-09-20)
- 参考文献数
- 30
The effect of temperature (15, 18, and 21°C) on the early development and starvation tolerance of yellow goosefish Lophius litulon was investigated. The periods of initiation of first feeding and starvation tolerance were shortened with increasing temperature. The period of first feeding varied from 5 days after hatching (DAH) at 15°C to 3 DAH at 21°C. Yellow goosefish larvae can survive for approximately 9-15 DAH (50% mortality period) without feeding in 15-21°C, but such an extended period of starvation is considered to increase the cumulative mortality.