THE POPULATION-DYNAMIC CONSEQUENCES OF PHENOLOGICAL ASYNCHRONY BETWEEN PARASITOIDS AND THEIR HOSTS

1. Populations of hosts and parasitoids with discrete generations freq uently show imperfect phenological synchronization resulting in some h osts experiencing reduced or even no risk of parasitism. 2. The popula tion dynamic consequences of phenological asynchrony are explored by m odelling within-generation dynamics by a set of delay-differential equ ations. 3. Phenological asynchrony can stabilize an otherwise unstable interaction. The influence of the interaction between phenological as ynchrony and other stabilizing forces on the stability and equilibrium population densities of hosts and parasitoids is studied. 3. Prelimin ary results indicate that annual fluctuations in the synchrony between host and parasitoid populations can have a major effect on the persis tence of the interaction.