George, W.G.. 1974. Domestic cats as predators and factors in winter shortages of raptor prey. The Wilson Bulletin 86(4):384-396.
The reader who has digested my findings can imagine that a hawk visiting my study site in the winters of 1968-1971 was more apt to see a cat than a rodent
A continuous study of predation by three rural cats was conducted in Union County, southern Illinois, from 1 January 1968 through 31 December 1971. The results established a basis for examining the possibility that cat predation may result in depleted winter populations of microtine rodents and other prey of Red-tailed Hawks, Marsh Hawks, and American Kestrels.
Although one of the three cats never ate prey and each cat was assured an ample supply of daily food at home, all captured prey. Their combined predation removed an annual average of 483.5 vertebrates and 286.4 mammalian fetuses from a combined home range of 22 acres of field habitat and three acres of woods. By volume, the principal prey were non-adult cottontails, by frequency of captures, prairie voles. Rodents of seven species constituted 81.9 percent of the total combined diurnal-crepuscular- nocturnal catch, and over 95 percent of the crepuscular-nocturnal catch.
The cats obtained 92.6 percent of their average annual diurnal captures between 1 March and 30 November. Their hunting sucess in winter was very poor, probably as a result of prey shortages that their own prior predation may have helped create. It is suggested that when captures of preferred prey by skillful, experienced cats on their natal hunting grounds sharply decline, the home range of the cats contains few such prey for rodent-seeking hawks.
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