Habitat Selection and Movement Behaviour of Long-Nosed Potoroo in the Presence of Feral Cats

Abstract

The global biodiversity extinction crisis is attributed to a series of key threats, with the introduction and impacts of invasive predators considered among the most damaging. Given that effective large-scale lethal control is often not logistically or financially feasible, alternative solutions to promote the persistence of native wildlife most at risk of predation—critical weight range mammals—must be sought. Understanding habitat use and selection of native prey under predation pressure with widespread and common invasive predators, such as feral cats, can quantify habitat elements that may promote survival. We aimed to determine the movement behaviour of a population of critical weight range mammals persisting in the presence of feral cats. We established a trapping grid across ‘Bluegums’, French Island, in south-eastern Australia to collect morphometric, demographic and movement data by deploying GPS tracking devices on Long-nosed Potoroo (Potorous tridactylus trisulcatus). We used spatially explicit capture–recapture models to generate a potoroo density estimate, and autocorrelated kernel density estimators and dynamic Brownian Bridge Movement Models to examine home range and habitat use. Spatial overlap and habitat selection analyses were used to draw inferences about habitat selection and territoriality. Potoroos persisted at low densities and had large home ranges (7.3–12.5 ha). Individuals selected for structurally complex habitat and appeared reluctant to move across open areas, potentially in response to greater perceived predation risk. The fine-scale movement data in our study elucidate the extent to which potoroos rely on vegetation structure, suggesting that maintaining habitat cover and connectivity is likely to build resilience and aid potoroos and similar species to co-exist with feral cats. Given the ongoing threat feral cats pose to biodiversity, our results support the need for maintaining diverse, structurally complex vegetation to build ecosystem resilience to support improved conservation outcomes in the presence of invasive species.