|Seasonal changes in abundance and development of Calanus pacificus (Crustacea: Copepoda) in the Oyashio–Kuroshio Mixed Region|Kobari, T.; Nagaki, T.; Takahashi, K. (2004). Seasonal changes in abundance and development of Calanus pacificus (Crustacea: Copepoda) in the Oyashio–Kuroshio Mixed Region. Mar. Biol. (Berl.) 144(4): 713-721. hdl.handle.net/10.1007/s00227-003-1244-z
In: Marine Biology. Springer: Heidelberg; Berlin. ISSN 0025-3162, more
|Authors|| || Top |
- Kobari, T.
- Nagaki, T.
- Takahashi, K.
Seasonal changes in abundance and development of Calanus pacificus Brodsky were investigated by analyzing samples of different depth strata (0–150 m and 0–1000 m) collected monthly in the Oyashio–Kuroshio Mixed Region. Copepodite stage 5 (C5) emerged from dormancy and matured in early summer. A new generation appeared in July and developed into C5 during summer to autumn. Some of the summer generation arrested development at C5 and persisted below 150 m depth until the following early summer. Although the remainder matured and reproduced in October, a new generation was not observed at the surface during winter. These results suggest that C. pacificus shows two different life-cycle patterns, i.e. one generation annually, with overwintering C5 in deep waters, and two generations annually, with surface development during autumn to winter. The complex life-cycle patterns may be an adaptation to the highly fluctuating surface environment in the Oyashio–Kuroshio Mixed Region.