Urban cat (Felis Catus) movement and predation activity associated with a wet land reserve in New Zealand

Abstract

Context. House cats are increasingly suggested as having major ecological impacts in semiurban environments. Information on the activity of house cats is relatively scarce, especially in habitats such as wetlands. Aims. This study examines the movement and foraging behaviour of house cats living on the periphery of a wetland reserve in Christchurch city, New Zealand. Methods. Twenty-one domestic cats living in a suburban residential area were studied using radiotelemetry to determine home-range size, mean and maximum distances travelled into the adjacent wetland, and the proportion of time spent in the wetland over a 12-month period. Surveys of prey retrieval for 88 cats were also carried out by cat owners over the same 12-month period. Key results. Cat age and the distance of the cat's home from the periphery of the wetland were highly correlated with cat movement and hunting activity. These movements were not markedly influenced by season or time of day. Younger cats (<6 years of age) living on the periphery of the wetland had larger home-range sizes, moved significantly further into the wetland and spent a significantly greater proportion of time in the wetland. Cats living close to the wetland also brought a greater diversity and a greater total number of prey items to their home-site. Rates of predation were not significantly influenced by sex or whether the cat was wearing a bell. The most common prey items were introduced rodents and birds; however, 172 of 981 prey items were identified as a native common skink. Conclusions.Consequently, cats living in households on the wetland periphery currently pose a predation risk for the wetland species, and the impact of cats on the native skink population warrants further investigation. Implications. This study suggests that domestic cats will exploit wild habitats but that their potential impact will have both positive (predation of introduced pest species) and negative (occasional direct predation) effects on native wildlife. © CSIRO 2009.