LAUSR

Abstract Context. Domestic cats (Felis catus) are efficient and abundant non-native predators, recently labelled as primary contributors to global biodiversity loss. Aims. Specific research goals included determining the proportion of hunters, estimating hunting efficiency, identifying primary prey and examining predictors of kill rate and efficacy. Methods. We investigated hunting of wildlife by stray cats living in managed outdoor colonies on a barrier island in the southeastern USA, and monitored 29 stray cats seasonally in 2014 and 2015 using Kittycam video cameras. Key results. In total, 24 cats exhibited hunting behaviour and 18 captured prey. The estimated average daily predation rate from these successful hunters was 6.15 kills per 24-h period. Hunting effectiveness (percentage of capture attempts that translate to a kill) was an average of 44%. The most common type of prey captured was invertebrate (primarily Orthopteran and Hemipteran insects), followed by amphibians and reptiles. Eighty-three percent of kills occurred between dusk and dawn. Conclusions. Colony location (near undeveloped island habitat) was related to higher kill rates. Cat sex and nocturnal hunting activity were related to greater hunting efficiency. Implications. These results address the significant gap in knowledge about stray cat hunting activities, and raise conservation concerns for some groups of organisms (reptiles and amphibians) that have not been widely identified as vulnerable to cat predation.