Habitat use in a population of mainland Tasmanian feral cats, Felis catus

This study examined various aspects of the spatial ecology and diet of a mainland Tasmanian population of feral domestic cats, Felis catus, to provide data relevant to planning and implementing feral cat control programs. Radio telemetry was used to quantify home ranges in three cats, two males and one female. Home ranges were relatively small for wild living feral cats, mean range area being 125 ha for males and 35 hectares for females. Home range size varied seasonally in males but not in females. Increases in male home range area, unusual movements and changes in den use occurred in July and August indicating this to be the mating season. Male cats ranged widely in search of receptive females. Home range overlap varied extensively depending on sex and season. Inter-sexual overlap was extensive, all cats overlapped with at least one cat of the opposite sex. Intra-sexual overlap between males varied between the non-mating and mating season. Overlap was extensive in the non-mating season with adult males sharing core areas. However, overlap in the mating season was minimal and restricted to the edges of ranges. This suggested that seasonal territoriality occurred between the males in response to competition for a limited number of female cats. Feral cats exhibited habitat preferences favouring habitats which included at least some ground cover and avoiding habitat where ground cover was absent, even where prey was abundant. Patchy type habitats were the most utilised and was favoured for foraging activity. This reflected prey availability in those areas, and the cover which the habitat provides for hunting. Dense habitat was favoured for the location of den sites. The feral cats at Sandford were active throughout the period between dusk and dawn, while little activity occurred during the day. Distances travelled per hour were greatest at dawn and dusk, probably indicating that the (male) cats were moving to and from foraging areas as opposed to actively hunting. Hunting probably occurs throughout the night, as the main prey species were nocturnal not crepuscular. The diet of the feral cats at Sandford was dominated by introduced mammals, in particular rabbits. However, diet did not reflect prey availability. The occurrence of ~mall native mammals in the diet was not consistent with their apparent abundance in the study area. This indicated that cats may selectively prey on these species. The study concluded that the control of feral cat populations on a large scale in mainland Tasmania is not justifiable. However, selective control may be necessary and beneficial in special cases, such as to protect seabird rookeries and vulnerable or endangered populations of native animals.