Conference Paper

KittyCams: A new look at suburban free-roaming cat predation

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Abstract

Background/Question/Methods: Domestic cats (Felis catus) are extremely efficient and abundant non-native predators. The predation rate of the domestic cat remains a topic of considerable social and scientific debate and warrants attention using improved methodology. Previous predation studies relied on homeowner reports of wildlife take from prey returns to the household. We monitored the activities of 60 owned, free-roaming cats in suburban Athens, Georgia over a one year period (Nov. 2010- Oct. 2011) using KittyCam video cameras. KittyCams are animal-borne National Geographic “CritterCams” that allow recording of an animal-eye view without disrupting behavior. Cats were recruited through a survey about perceptions of domestic cats and free health screens and annual vaccinations were offered as an incentive for participation. Enrolled cats wore a video camera for 7-10 total days and all outdoor activity was recorded for analysis. Specific research goals related to predation included: 1) quantifying the frequency of cat interactions with native wildlife 2) identifying common prey species of suburban cats 3) examining predictors of outdoor behavior. Results/Conclusions: We collected an average of 37 hours of footage from each project cat. Preliminary results indicate that a minority of roaming cats (44%) hunt wildlife and that reptiles, mammals and invertebrates constitute the majority of suburban prey. Hunting cats captured an average of 2 items during seven days of roaming. Carolina Anoles (Anolis carolinensis) were the most common prey species and these new results suggest that additional research is needed regarding cat impact on suburban reptile populations. Eighty-five percent of wildlife captures were witnessed during the warm season (March-November in the southern US). Twenty-three percent of cat prey items were returned to households; 49% of items were left at the site of capture and 26% consumed. These results suggest that previous studies on pet cat depredation vastly underestimated capture rate. Cats roaming in rural areas were more likely to be hunters while cat age, sex, and time spent outside did not significantly influence hunting behavior. The KittyCams project aims to contribute reliable statistics and irrefutable images to the growing debate over free-roaming cats in the environment. Scientific manuscripts and educational materials for the general public are currently in preparation.

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