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The feeding ecology of cape vultures Gyps coprotheres in a stock-farming area

Department of Zoology, University of the Witwatersrand, Johannesburg, South Africa; A.F. Boshoff; The Lakes Nature Conservation Station, Private Bag 6546, George, South Africa
Biological Conservation 01/1986; DOI:10.1016/0006-3207(86)90027-3

ABSTRACT Cape vultures Gyps coprotheres in the southwestern Cape Province feed exclusively on sheep carcasses, within a limited foraging area. The size and shape of the foraging range was determined by means of a postal survey and confirmed by a radio-tracking study. The quantity of food available within the range, while seasonally variable, was estimated to exceed the colony's requirements. Data pertaining to daily feeding forays of individuals, monthly foraging patterns of the colony and the growth of nestlings indicated no seasonal shortages in the amount of food obtained. The colony remains susceptible to the effects of poisons used in the area; levels of contaminants recorded in most eggs are considered low.

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