Title:
Food requirements and the timing of breeding of a Cape Vulture colony
Author(s):
Publication Year:
1993
Abstract:
Annual food requirements of a Cape Vulture Gyps coprotheres family, comprising one nestling and two adult birds, and a breeding colony were estimated. A family required 226,1 kg meat during a nestling period of 136 days, and 524,4 kg annually. The greatest family food requirements (average 1,98 kg/day) occurred between 60 and 100 days after hatching. The period between 60 and 100 days after hatching was the most critical period of food demands, because (a) this was the period of greatest nestling food requirements, (b) only one parent could be away from the nest at a time, and (c) daily family food intake was effectively constant due to temporal constraints on foraging. The estimated food requirements of a breeding colony comprising 152 breeding pairs and 98 nonbreeding birds was 89 388 kg meat annually, and 36 892 kg during the nestling period, with the highest food requirements (302 kg/day) occurring during September and October. In summer rainfall areas of South Africa, the highest numbers of wild ungulate and livestock mortalities occurred during September and October. It is suggested that, due to physical, physiological and environmental constraints on parent birds' ability to provide food, the breeding cycle of Cape Vultures is timed so that the period of greatest food consumption coincides with the period of greatest food availability.
Publication Title:
Ostrich: Journal of African Ornithology
Volume:
64
Issue:
2
Pages:
86-92
Item Type:
Journal Article
Language:
en