Sammanfattning

The distribution of the leptocephalus larvae of European (Anguilla anguilla) and American (Anguilla rostrata) eels collected during recent Sargasso Sea surveys was used to model larval drift. The drift trajectories of individual larva were back-calculated to the estimated time of spawning, using current data from two global oceanographic assimilation models. The results of both models give the same overall result; widespread spawning extended in time from December to March. The drift was also calculated forwards for approximately 1 year. The forward drift modelling showed that most leptocephali remained in the area south of the Subtropical Frontal Zone. One conclusion is that the majority of leptocephali remain trapped and possibly die in the retention area. A small proportion of leptocephali are entrained into the Gulf Stream system. An implication is that the spawning success may be highly sensitive to oceanographic and climatic factors that alter the dispersion of leptocephali out from the retention area. An alternative interpretation is that the surveys were made too late after the peak spawning period and that the core spawning area was missed.

Publicerad i

Canadian Journal of Fisheries and Aquatic Sciences
2018, Volym: 75, nummer: 2, sidor: 224-234
Utgivare: CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS

SLU författare

• Westerberg, Håkan

  • Institutionen för akvatiska resurser (SLU Aqua), Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Oceanografi, hydrologi, vattenresurser


Publikationens identifierare

DOI: https://doi.org/10.1139/cjfas-2016-0256

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/93935