The feeding habits of wild and domestic felids in New Brunswick, Canada

Abstract

Domestic cats (Felis catus) are major predators of wildlife and are linked to high mortalities of wildlife species. Despite known conservation risks, feeding habits of free-ranging cats in Canada are understudied. This study used stable isotope analyses to compare the diets of four cat types in New Brunswick, Canada: 1) free-ranging cats, 2) house cats, 3) Canada Lynx (Lynx canadensis) and 4) Bobcats (L. rufus). To quantify diet and trophic niche, the stable isotopes of carbon (13C) and nitrogen (15N) were measured in fur samples of cats and putative prey, including small mammals, birds, and commercial pet foods. There were distinct differences in diet and trophic niche between domestic and wild cats. House and free-ranging cats predominantly consumed artificial foods (>90% of diet), while bobcats and lynx consumed wild prey. There were no credible differences in diet or trophic niche observed between house and free-ranging cats, suggesting high levels of supplemental feeding and human-subsidization of free-ranging cat populations in New Brunswick.