Modeling life stage dynamics of Pseudocalanus spp. (Copepoda: Calanoida) from Prince William Sound, Alaska

Abstract

A stage at age 1D numerical model (SAGE) was developed to describe reproduction, development, and growth of a group of neritic copepods Pseudocalanus spp., and to predict structure and demography of this group. The model tests the relative importance of female abundance, temperature and food on productivity. During spring and the beginning of the summer, stage-specific abundance data from one location in Prince William Sound (PWS), Alaska were available to evaluate the reproductive timing and provide model validation. Development of Pseudocalanus spp. was modelled as synchronous, without overlapping broods. Molting costs and assimilation efficiency were estimated from literature data on other calanoid copepods. Wood's population surface method was used to produce a stage at age mortality (SAM) model to evaluate per capita instantaneous stage-specific mortality rates from the field data. The model confirmed the assumption that the abundance of these copepods was controlled by temperature and temporal/stage-to-stage variation in mortality rates, rather than by food availability.