Ecological factors influencing invasive predator survival and movement: insights from a continental-scale study of feral cats in Australia

Abstract

Feral cats (Felis catus) pose a significant global threat to biodiversity, primarily through predation, disease and competition. A key gap in parameterizing models for improving management decisions for feral cat control relates to factors that drive feral cat survival and movement in the wild. Our study objective was to conduct the first continental-scale analysis of survival rates and displacement distances for feral cats. We collated data on 528 feral cats from telemetry studies in naturally-vegetated landscapes across Australia. Using Cox-proportional hazards models, we investigated the effects of sex, presence of larger predators (dingoes, Canis familiaris and introduced foxes, Vulpes vulpes), presence of introduced prey (rabbits, Oryctolagus cuniculus), body mass, landscape productivity and feral cat density on feral cat survival. We also analysed the effects of sex, body mass and landscape productivity on feral cat displacement using linear mixed model analysis. Feral cat survival was positively associated with presence of dingoes and increasing body mass, whereas there was no clear association between feral cat survival and sex, presence of rabbits, or cat density. Presence of foxes had a strong negative effect on feral cat survival, but the hazard ratio was associated with considerable uncertainty. Net displacement of male feral cats was nearly two times further than that of females, and the proportion of feral cats making long-distance movements was greater in landscapes with low productivity. Increasing body mass of feral cats was positively related to net displacement, with heavier cats moving further. Analysis of metadata from telemetry studies can provide valuable insights into wildlife survival rates and movement behaviour. Our findings will help inform the development of effective management strategies and improve feral cat management for biodiversity conservation.