Life histories of the copepods Pseudocalanus minutus, P. acuspes (Calanoida) and Oithona similis (Cyclopoida) in the Arctic Kongsfjorden (Svalbard) |
| |
Authors: | Silke Lischka Wilhelm Hagen |
| |
Institution: | (1) Institute for Polar Ecology, Kiel University, Wischhofstrasse 1–3, Geb. 12, 24148 Kiel, Germany;(2) Marine Zoology (FB 2), Bremen University (NW 2A), P.O. Box 330440, 28344 Bremen, Germany |
| |
Abstract: | The year-round variation in abundance and stage-specific (vertical) distribution of Pseudocalanus minutus and Oithona similis was studied in the Arctic Kongsfjorden, Svalbard. Maxima of vertically integrated abundance were found in November with 111,297 ind m−2 for P. minutus and 704,633 ind m−2 for O. similis. Minimum abundances comprised 1,088 ind m−2 and 4,483 ind m−2 in June for P. minutus and O. similis, respectively. The congener P. acuspes only occurred in low numbers (15–213 ind m−2), and successful reproduction was debatable. Reproduction of P. minutus took place in May/June, and stage distribution revealed a 1-year life cycle with copepodids CIII, CIV, and CV as the overwintering
stages. Oithona similis exhibited two main reproductive peaks in June and August/September, respectively. Moreover, it reproduced more or less continuously
throughout the whole year with all stages occurring during the entire sampling period, suggesting two generations per year.
Both species migrated towards greater depth in November, but O. similis preferred to stay longer in the upper 100 m as compared to Pseudocalanus. The reproduction of the two species in Kongsfjorden seemed to be linked to phytoplankton dynamics. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|