Cooperation-mediated regime shifts in a disease-dominated prey–predator system

Predator foraging facilitation is well-observed in predator–prey interactions and has been explored in ecological literatures. However, the impact of such behavioral pattern on the ecological dynamics with infection in prey species is less studied. Motivated by this, we contemplate the dynamics of a predator–prey model with infection in fearful prey in presence of cooperative behavior among predators. Our results reconfirms the destabilizing effect of infection rate and the stabilizing effect of fear factor on the system dynamics. However, under different ecological conditions the infection rate causes the eco-epidemiological system to be sensitive to initial population size and vulnerable to small perturbations, as the proposed model supports multiple stable steady states. The fear-induced eco-epidemiological model potentially exhibits various types of bistability phenomena including bistability between the infection-free equilibrium and stable coexistence equilibrium, and bistability between population cycles and infection-free equilibrium depending upon the strength of cooperation, rate of infection and birth rate of healthy prey. We also observe the phenomenon of bubbling in the intermediate range of predator’s intrinsic growth rate. The model predicts a high risk of catastrophic extinction of infected individuals around the homoclinic and saddle–node bifurcations resulting from a stronger strength of cooperative hunting among predators. The ecological theories developed in this work might provide a new insight to better understand the fate of an ecosystem involving parasites.