The domestic cat is a widespread and abundant predator that negatively impacts a wide range of species. However, the predation activity and prey type of free-ranging cats may vary between areas with different levels urbanisation. Previous analyses of cat diet have used differing techniques to measure predation that often differ with one another. Given the variability in these methods we hypothesised that cats in rural areas will have a more diverse diet than in urban areas and their predation rate may be higher than those in the urban sites. Moreover, we hypothesized that the diet of urban cats should be highly influenced by anthropogenic food. We selected sites across a rural-to-urban gradient and used three methods of analysis to determine prey in the diet (cat stomachs, cat scats, and prey brought home). We collected 81 stomachs, 409 scats, and 337 prey items of free-roaming cats from six study sites located in southern and eastern Poland. We found seasonal and habitat related differences in prey composition. The proportion of scats and stomachs containing vertebrate varied from 17% in urban areas to 79% in one of the rural areas. Small rodents were the dominant prey category, followed by birds and soricomorphs. Anthropogenic food was found to be an important part of urban cats’ diet, but its significance decreased with a decrease in urbanisation level. Both predation rate and prey diversity were highest in rural areas. While diet analysis provided a better estimation of cat predation rate, the detailed prey examination provided better insight into less common taxa killed by the cats, such as reptiles and small mustelids. Our results contribute to the discussion about the risks associated with the activity of free ranging cats especially in areas with high conservation values.

Growing urbanization leads to an increased risk of parasite spread in densely inhabited areas. Free-ranging cats can be locally numerous and come into frequent contact with both wildlife and humans. Cats are thus expected to contribute to parasitic disease transmission. In our study, we investigated the prevalence of endoparasites in free ranging cats in urban areas of Kraków city, based on necropsy of road-killed cats in relation to sex and diet of cat, season and habitat type. We found that 62% of 81 cats were infected with endoparasites with Toxocara cati being the most prevalent. In total, we identified seven parasite species. The number of parasite species was higher in suburban habitats and aside from Eucoleus aerophilus the prevalence of all parasites was higher in cats from suburban areas than in the individuals living in the city urban core. The prey of examined cats included mostly rodents, followed by soricomorphs and birds, which can all serve as paratenic hosts. Based on our results, we suggest that cats in urban areas should be considered as a serious potential zoonotic threat. Implementation of proper veterinary control and wider education on the topic is recommended.

The stoat (Mustela erminea) is a small mustelid predator specialising on rodent species. However, they also can eat various alternative prey in different parts of their range. In the literature, sexual dimorphism differences in this species are reflected in different diet preferences with males hunting on larger prey than females. The aim of this study was to assess food habits of stoats trapped in two study sites in Norway. We analysed stomach content in relation to body mass, sex and season. In total, 137 stomachs, 101 of males and 36 of females, were analysed. Males (201.80±37.71 g) were significantly heavier than females (85.06±13.26 g) (F=258.88, df=1, p≤0.0001). Six food categories were identified, dominated by small rodents, followed by anthropogenic food, birds, insectivores and invertebrates. The most common prey species were bank vole (Myodes glareolus) and tundra vole (Microtus oeconomus). We found no evidence of trophic niche segregation between male and female stoats despite body size differences between sexes. There were also no significant differences in diet of all stoats between seasons. The trophic annual niche breadth of all stoats was B=3.88 and highly overlapped between sexes (O jk =0.97). The results confirm that the stoat in Norway is a generalist predator able to profit on human food refuse found in close proximity to permanent residents and summer cabins.