Range of feral cats in NZ forest

Fitzgerald, B. M., & Karl, B. J. (1986). Home range of feral house cats (Felis catus L.) in forest of the Orongorongo Valley, Wellington, New Zealand. New Zealand journal of ecology, 9, 71-82.

The home ranges of four male and five female feral house cats (Felis catus) were studied by radiotelemetry. In the narrow, steep-sided valley the home ranges of cats were linear, with an average length of 6.34 km for males and 3.83 km for females; only large males crossed the river. Females with kittens had small home ranges of 0.84 to 2.0 km. Home ranges of animals of the same sex, including breeding females, overlapped considerably. The social organisation of feral cats at low density differs little from that of higher-density freeranging domestic cats

Eradication and control of feral dogs in Galápagos

Barnett, B. D. (1986). Eradication and control of feral and free-ranging dogs in the Galápagos Islands. In Proceedings of the Twelfth Vertebrate Pest Conference (1986) (8 pp.).

The history of canid introduction in Galápagos, their impact on biodiversity and the control and eradication by different methods, mainly poisoning with 1080 and chemical sterilisation.

After eradication in some areas, some mesopredator release effect was detected and cats further threatened iguanas populations. Sea lions became free of this danger, but cattle invaded areas previously occupied by dogs.

Cats' diet on some Pacific islands

Jarvis and Howlnad

R.D. Kirkpatrick and Mark J. Rauzon. 1986. Foods of Feral Cats Felis catus on Jarvis and Howland Islands, Central Pacific Ocean. Biotropica, 18 (1): 72-75

Food habits of feral cats (Felis catus) were studied on two small uninhabited islands in the central Pacific Ocean. Cat stomach contents, collected on Howland Island in May 1979 and on Jarvis Island during May 1979 and June-July 1982, revealed that sooty terns (Sterna fuscata) were the primary prey species. Other seabirds, lizards, insects and, on Jarvis Island, house mice were also eaten. Fetal cats may have virtually exterminated the wedge-tailed shearwater colony on Jarvis Island.

Kermadec
Fitzgerald, B.M.; Kark, B.J. & Veitch, C.R. 1991. The diet of feral cats (Felis catus) on Raoul Island, Kermadec Group. New Zealand Journal of Ecology 15(2): 123-129.

Feral cats became established on Raoul Island some time between 1836 and 1872; the prey available to them included a great variety of nesting seabirds, few of which are present now, landbirds and kiore (Rattus

exulans). Norway rats reached the island in 1921, providing additional prey for cats, but also another potential predator of seabirds. The diet of cats is described from guts and scats collected between 1972 and 1980. Rats are the main food, with land birds second in importance, and seabirds are now a minor item. More than 90% of the rats eaten by cats are kiore although more Norway rats than kiore are trapped. Eradicating cats from Raoul Island is feasible but because Norway rats too are important predators of birds on islands, it is likely that eradicating cats without also eradicating Norway rats will do little to restore the diversity of bird species on Raoul Island, although the densities of a few species now present might be increased.

Hawai'i
Hess, S. C.; Hansen, H.; Nelson, D.; Swift, R. & Banko, P. C. 2007. Diet of feral cats in Hawai'i Volcanoes National Park. Pacific Conservation Biology, 13: 244–249.

We documented the diet of feral cats by analysing the contents of 42 digestive tracts from Kilauea and Mauna Loa in Hawai'i Volcanoes National Park. Small mammals, invertebrates, and birds were the most common prey types consumed by feral cats. Birds occurred in 27.8-29.2% of digestive tracts. The total number of bird, small mammal, and invertebrate prey differed between Kilauea and Mauna Loa. On Mauna Loa, significantly more (89%) feral cats consumed small mammals, primarily rodents, than on Kilauea Volcano (50%). Mice (Mus musculus) were the major component of the feral cat diet on Mauna Loa, whereas Orthoptera were the major component of the diet on Kilauea. We recovered a mandible set, feathers, and bones of an endangered Hawaiian Petrel (Pterodroma sandwichensis) from a digestive tract from Mauna Loa. This specimen represents the first well-documented endangered seabird to be recovered from the digestive tract of a feral cat in Hawai'i and suggests that feral cats prey on this species.

Smucker, T. D., G. D. Lindsey, & S. M. Mosher. 2000. Home range and diet of feral cats in Hawaii forests. Pacific Conservation Biology 6: 229–237.

Feral cat Felis catus home range in a Hawaiian montane wet forest and their diet in three habitats - montane wet forest, subalpine dry forest, and lowland dry forest - were determined to provide baseline ecological data and to assess potential impacts to native terrestrial fauna. Seven cats (three males and four females) were captured in 624 trap nights. Mean weight of adult cats was 2.85 0.27 (SE) kg for males and 1.87 0.03 kg for females. Mean diurnal home range using the adaptive kernel method was 5.74 2.73 km² for three males and 2.23 0.44 km²  for two females. Daytime locations were always within the montane wet forest with the borders on one or more sides of the home ranges of all cats defined by open grassland pastures. Rodents comprised the majority of the cat diets in all three habitats, with the frequencies of occurrence between 0.88 and 0.91. Bird remains were a regular component of the diet of cats, with montane wet forest having the highest frequency of occurrence (0.68), followed by subalpine dry forest (0.53). and lowland dry forest (0.21).