Variability of copepods as seen in a coupled physical-biological model of the Baltic Sea

A key factor for the survival of fish larvae is the availability of prey (nauplii and copepodites) at the right time, place, and quality. This depends on several physical and biological processes and factors which can be studied theoretically by means of coupled physical-biological models with a stage-resolving zooplankton component. This study is based on an advanced ecosystem model of the Baltic Sea (ERGOM) with an increased resolution of the zooplankton stage variable. The model zooplankton consists of five stages: eggs, nauplii, two aggregated groups of copepodites, and adults. Food availability and temperature control the transfer processes, such as reproduction, hatching, and moulting. A simulation of the annual cycle is used to explore theoretically the temporal and spatial development of the various stages in relation to the physical forcing and the food web interactions. The dynamic equations for the “model copepod" were guided by Pseudocalanus', however, the model amounts to a stage-resolving description of aggregated zooplankton state variables. The effects and implications of increased process resolution are highlighted by comparisons of stage-resolving model runs and simulations with a single bulk-zooplankton variable.

Article from Marine Science Symposia Vol. 219 - "Hydrobiological variability in the ICES Area, 1990-1999", symposium held in Edinburgh, 8-10 August 2001. To access  the remaining articles please click on the keyword "MSS Vol. 219".