Subsidised by junk foods: factors influencing body condition in stray cats (Felis catus)

Domestic cats (Felis catus) are one of the most widely distributed and successful carnivores globally. While cats are popular pets, many unowned, ‘stray’ cats live freely in anthropogenic environments at high densities where they make use of anthropogenic resources. These stray cats present a management challenge due to concerns about wildlife predation, pathogen transmission, public nuisance and threats to cat welfare (e.g. vehicle collisions). In Australia, there are few studies of strays compared with pet cats or feral cats (free-roaming cats in rural areas that are independent of resources provided by humans). To contribute original data about stray cat biology, the carcasses of 188 euthanised stray cats were collected from Perth, Western Australia. Cats were assessed for general health, age, reproduction, diet and gastrointestinal parasite biomass. The influence of cat demographics, collection location, season, parasite biomass, diet and history of supplemental feeding by people were tested against body condition. Overall, strays were physically healthy and reproductive, with few life-threatening injuries or macroscopic evidence of disease; however, helminths were extremely common (95% of cats) and pose a threat. Nearly 40% of strays consumed wildlife, including two species of endemic marsupial. Alarmingly, 57.5% of strays were scavenging vast amounts of refuse, including life-threatening items in volumes that blocked their gastrointestinal tracts. These findings illustrate that strays need to be removed from anthropogenic environments for their own health and welfare and to prevent continued breeding. Targeted control programmes should prioritise removal of cats from areas where refuse is common and where valued native fauna exist