The small home ranges and large local ecological impacts of pet cats

Abstract Domestic cats ( Felis catus ) are a conservation concern because they kill billions of native prey each year, but without spatial context the ecological importance of pets as predators remains uncertain. We worked with citizen scientists to track 925 pet cats from six countries, finding remarkably small home ranges (3.6 ± 5.6 ha). Only three cats ranged > 1 km 2 and we found no relationship between home range size and the presence of larger native predators (i.e. coyotes, Canis latrans ). Most (75%) cats used primarily (90%) disturbed habitats. Owners reported that their pets killed an average of 3.5 prey items/month, leading to an estimated ecological impact per cat of 14.2‐38.9 prey ha −1 yr −1 . This is similar or higher than the per‐animal ecological impact of wild carnivores but the effect is amplified by the high density of cats in neighborhoods. As a result, pet cats around the world have an ecological impact greater than native predators but concentrated within ~100 m of their homes.