Model-supported estimation of mortality rates in Baltic cod (<Emphasis Type="Italic">Gadus morhua callarias</Emphasis> L.) larvae: the varying impact of 'critical periods'
1.Marine Ecology Department,Institute of Marine Sciences Kiel,Kiel,Germany;2.Marine Ecology Department,Institute of Marine Sciences Kiel,Kiel,Germany;3.Greenland Institute of Natural Resources,Nuuk,Greenland
Abstract:
Background
Changes in the survival-rate during the larval phase may strongly influence the recruitment level in marine fish species.
During the larval phase different 'critical periods' are discussed, e.g. the hatching period and the first-feeding period.
No such information was available for the Baltic cod stock, a commercially important stock showing reproduction failure during
the last years. We calculated field-based mortality rates for larval Baltic cod during these phases using basin-wide abundance
estimates from two consecutive surveys. Survey information was corrected by three dimensional hydrodynamic model runs.