ecological modelling 206 ( 2 0 0 7 ) 213–230 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/ecolmodel Parameterisation of a zooplankton population model for Pseudocalanus elongatus using stage durations from laboratory experiments Christoph Stegert a,∗ , Markus Kreus a , Francois Carlotti b , Andreas Moll a,∗ a Institut f ¨ ur Meereskunde (IfM), Universit ¨ at Hamburg (ZMK-ZMAW), Bundesstr. 53, 20146 Hamburg, Germany b Universit´ e de la M´ editerran´ ee, Centre d’Oc´ eanologie de Marseille (COM), Rue de la Batterie des Lions, 13007 Marseille, France article info Article history: Received 16 June 2006 Received in revised form 12 April 2007 Accepted 18 April 2007 Published on line 14 June 2007 Keywords: Stage-structured population model Copepod Pseudocalanus Parameterisation Generation times abstract A zero-dimensional population model based on a copepod model by Fennel (2001) was parameterised according to the population dynamics of Pseudocalanus elongatus. Biologi- cal functions were chosen particularly and formulated to get realistic characteristics of growth and development under conditions of temperature and food reported for the North Sea. Parameter values for weight, hatching and assimilation were taken from the litera- ture, employing robust values from various published studies and parameters derived from similar species. The influence of temperature on feeding and basal respiration and the half-saturation of ingestion were obtained indirectly by successive fitting of developmental times to stage durations observed from laboratory culture studies. A data set from Klein Breteler et al. (1995) was used, which includes estimates at temperatures of 5, 10, 15 and 20 ◦ C each at food concentrations of <70, ∼100 and >200 gCl -1 . Simulations at each sce- nario showed the effectiveness of adjustments. The sensitivity of model parameter values was tested in terms of variances in generation times. The analysis exhibited the sensitiv- ity of development to specific metabolic processes, while the importance of temperature is reflected in its recurrence within several processes. The model is able to represent consis- tent development patterns, while reflecting the physiological complexity of a population of P. elongatus. © 2007 Elsevier B.V. All rights reserved. 1. Introduction Fennel (2001) formulated a stage resolved zooplankton pop- ulation model adapted to Pseudocalanus sp. in the Baltic Sea, which calculates biomass and abundance for five model stage groups. Necessary process parameterisation was derived from the literature and the Baltic Monitoring Programme to study the physical impact on zooplankton dynamics and the inter- ∗ Corresponding authors. E-mail addresses: stegert@ifm.uni-hamburg.de (C. Stegert), moll@ifm.uni-hamburg.de (A. Moll). action with fish larvae in the frame of the German GLOBEC Programme (Fennel and Neumann, 2003). Within this project we aimed to study the North Sea zooplankton development, where copepods also form the major part of the marine mesozooplankton throughout the year. For both regional seas the three copepod groups Acartia spp., Temora longicornis and Pseudo-/Paracalanus dominate the biomass, but for the North Sea a number of additional cope- 0304-3800/$ – see front matter © 2007 Elsevier B.V. All rights reserved. doi:10.1016/j.ecolmodel.2007.04.012