Fungal parasitism in a copepod population: the effects of Aphanomyces on the population dynamics of Boeckella dilatata Sars

Abstract

Growth parameters of a Boeckella dilatata (Copepoda: Calanoida) population in Lake Hayes over 16 months were calculated in the presence and absence of a fungus, Aphanomyces sp. (Phycomycetes: Saprolegniaceae) which kills the eggs and increases mortality of the females. Parasitism was highest during winter and the following summer when birth rates were depressed by up to 14.3%. When the incidence of Aphanomyces is high, parasitism could be important in regulating the growth of a copepod population.