Speaker
Description
We consider an eco-epidemiological model, where an infectious disease circulates within a predator population. If the disease only alters the attack rate of predators (a so-called trait-mediate effect), this reduces the equilibrium predator population size – no matter whether the disease increases or decreases the attack rate. By contrast, the prey population size at equilibrium can increase (for an enhanced attack rate) or decrease (for a reduced attack rate). Furthermore, if predators and prey cannot coexist in the absence of trait-mediated effects, disease-induced increases in the attack rate can enable the survival of predators. Mathematically, this occurs via transcritical bifurcations (for frequency-dependent disease transmission) or saddle-node bifurcations (for density-dependent disease transmission). The results underline the importance of trait-mediated effects and provide fundamental insights from generic eco-epidemiological models.
