MODELING THE REPRODUCTION OF CENTROPAGES-TYPICUS (COPEPODA, CALANOIDA) IN A FLUCTUATING FOOD-SUPPLY - EFFECT OF ADAPTATION

A mathematical model of the reproduction of the copepod Centropages typicus is proposed, which takes into account the physiological processes involved in the transformation of available food into eggs (ingestion, assimilation, storage, maturation) and the associated metabolic rates. The principal hypothesis is that maturation is regulated by the level of energy storage. The simulations fit adequately to the measurements of the egg-laying rate in constant as well as in varying food concentrations. It is demonstrated that the classical steady-state relationships between food and egg laying rate do not provide a good estimation of the fecundity of C. typicus when food fluctuates periodically. The model predicts that the average egg-laying rate of a population of C. typicus changes radically for periodicities of food variation <̃2 days. The average rate is insensitive to the periodicity of food variation for a period >2 days. It is suggested that the frequency of food variation is a parameter as important as quality and quantity, which must be taken into account to predict adequately the egg production of females during their lifespan. © 1990 Oxford University Press.