Diet overlap between wild and domestic cat: advantages from being generalist

Biró, Z.,J. Lanszki, L. Szemethy, M. Heltai & E. Randi. 2005. Feeding habits of feral domestic cats (Felis catus), wild cats (Felis silvestris) and their hybrids: trophic niche overlap among cat groups in Hungary. Journal of Zoology, 266 (2): 187–196.

The feeding habits of feral domestic cats Felis catus (n=264), wild cats Felis silvestris (n=22) and their hybrids (n=30) were investigated in Hungary. Cat groups were identified taxonomically by morphological and molecular methods. Diet components were identified in stomach contents and faeces collected from the recta. In each cat group, abundant small mammals were dominant in the diet (relative frequency of occurrence: feral domestic cat, 61–82%, depending on regions; wild cat, 70%; hybrid, 59%). Birds were the second most important quarry (2–7%, 16% and 20%, respectively in the three cat groups), while the contribution of hares (1–2%, 5% and 3%, respectively) and other taxa was not significant. Every cat group preyed on small-sized animals (<50 g; 89–96%, 80% and 80%, respectively), terrestrial (91–98%, 84% and 86%, respectively) and wild (71–73%, 87% and 77%, respectively) prey. Standardized trophic niche breadth was typically very narrow (BA=0.07–0.16, 0.13 and 0.17, respectively). Feral domestic cats occasionally consumed household food (2–7%) and domestic animals (4–8%). This could mean that feral domestic cats have an advantage over wild cats that are food specialists. The trophic niche overlap between cat groups was high (77–88%). Food composition and feeding habits, (weight, zonation and environmental association of consumed prey) of feral domestic cats, however, was different compared to wild cats, which indicated the possibility of partial resource partitioning. The values for hybrids were between the two groups. As well as the stable presence of feral domestic cats (mean population density, D=1.34 individuals/1000 ha) based on field live-trapping, hybrids are also present (D=0.10), leading to continuous hybridization. This can threaten the population of wild cats, which are present at a low density (D=0.17).