Understanding the hydra effect in predator-dependent functional response models

The seemingly paradoxical increase of a species' means density in response to greater mortality is an interesting research topic recent times, and such type counterintuitive known as the hydra effect. Identifying predicting consequences increased crucial for conservation biology population management. existence effect Gause-type models feature mathematical ecology. However, still not investigated predator-dependent functional responses. present paper addresses presence either prey predator species two-species unstructured with logistic growth density-independent death rate. Our results show that positive density-dependence predators (grouping behavior or cooperation) trophic functions shows species, whereas negative (interference) species. Moreover, former case, always exhibits at stable state, whether latter state when has self-effects equilibrium. In our considered models, prey's suggest intraspecific competition rate coefficient would be sufficiently small so positively related its per capita case cyclic dynamics, typical unstable systems saturating