Journal
DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS
Volume 171, Issue -, Pages -Publisher
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.dsr.2021.103508
Keywords
Atlantic water; East Icelandic water; Vertical distribution; Reproduction; Lipid content; Diapause
Categories
Funding
- Danish government through the research program Changes in marine climatic and oceanographic conditions in the waters between the Faroes and Greenland, and their effects on plankton and fish
Ask authors/readers for more resources
The study on the copepod Calanus finmarchicus in the southwestern Norwegian Sea reveals that it reproduces, feeds, and accumulates lipids in surface waters during spring and summer for overwintering at depth. The confluence of warm and saline Atlantic Water with cold and less saline subarctic waters establishes the dynamic Iceland Faroe Front. The reproductive phenology and stage development of Calanus finmarchicus likely influence feeding and competition between herring and mackerel in Faroese waters.
A seasonal study of the life cycle and reproductive biology of the copepod Calanus finmarchicus ? the dominant zooplankton species and a key link between the lower and higher trophic levels within the southwestern Norwegian Sea - is presented. C. finmarchicus reproduces, feeds and accumulates lipids during spring and summer within surface waters, which enables it to survive overwintering at depth until the following spring. An inflow of warm and saline Atlantic Water (AW) enters from the southwest and meets the cold and less saline subarctic waters (SAW) flowing from the north and west. This confluence establishes the dynamic Iceland Faroe Front. The study includes seven cruises, conducted from July 2013 to July 2014. Ascent occurred earlier and over a prolonged period in AW compared to the SAW. The peak egg production per capita occurred in April (43 eggs female-1 d-1) and May (13 eggs female-1 d-1) in SAW and AW, respectively. The higher productivity in SAW can be explained by larger female size, increased lipid content and better feeding conditions. The increased egg production rates in May in AW were not reflected in an increased abundance of young copepodite stages in June, potentially due to a decoupling between early ascent and the late onset of the bloom. Descent, largely comprised by the pre-adult stages, to overwintering depths was already initiated in June in both regions. This coincides with increased lipid content, being significantly higher at depth compared to the surface in late summer. A smaller portion of individuals remained within the upper layers to spawn a second generation in August in both regions, increasing the abundance and biomass. The reproductive phenology and stage development of C. finmarchicus likely influence feeding and competition between herring and mackerel and the duration of their stay in Faroese waters.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available