SS1.09 Fisheries Population Linkage Spatial and Temporal Variation in Zooplankton
Date: Wednesday, June 12, 2002
Time: 10:15:00 AM
Location: Carson C
 
HinrichsenHH, Institute of Marine Sciences, Kiel, Germany, hhinrichsen@ifm.uni-kiel.de
Moellmann, C, , Institute of Marine Sciences, Kiel, Germany, cmoellmann@ifm.uni-kiel.de
Voss, R, , Institute of Marine Sciences, Kiel, Germany, rvoss@ifm.uni-kiel.de
Koester, F, W, Institute of Marine Sciences, Kiel, Germany, fkoester@ifm.uni-kiel.de
Kornilovs, G, , Latvian Fisheries Research Institute, Riga, Latvia, georgs_k@latfri.lv
 
THE IMPACT OF PHYSICAL FORCING ON EASTERN BALTIC COD LARVAL SURVIVAL: A COUPLED HYDRODYNAMIC/BIOLOGICAL MODELLING APPROACH
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Using a coupled hydro/trophodynamic individual based model on drift and feeding we considered physical/biological processes on the population of larval cod in the Baltic. The main purpose of this study was i) to analyse temperature, food and size dependent growth of Baltic cod larvae and ii) to identify its intra- and interannual variability for drift periods based on the timing of peak spawning. Temporally and spatially resolved simulated flow fields were used to investigate the potential drift of Baltic larval cod from the centre of spawning effort in the Bornholm Basin towards different nursery areas. Estimates of temporally and spatially resolved prey fields appropriate for feeding larvae were derived from a zooplankton data base. Besides the role of advection, this study describes the impact of trophodynamic processes on growth and starvation mortality at the level of individual larvae. Because of the strong decay of the calanoid copepod Pseudocalanus elongatus in the central Baltic during the last two decades the results of the coupled model runs indicate that larval cod in the eastern Baltic changed from a food non-limited to a food limited state. Starvation mortality was found to be important exclusively for first feeding larvae.