The feeding ecology of Cape vultures, Gyps coprotheres in a stock-farming area. Biol Conserv

Department of Zoology, University of the Witwatersrand, Johannesburg, South Africa
Biological Conservation (Impact Factor: 3.76). 01/1986; 35(1):63-86. DOI: 10.1016/0006-3207(86)90027-3


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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    • "Accurate estimates of their population can be made by conducting surveys in these sites during certain months of the year and times of the day [5]. As a result, improved monitoring techniques consist of counting birds at their breeding or roosting sites early in the morning or late in the evening before or after their daily foraging trips [6]. The common black kite is an accipitrid and is widely distributed in the old World [7]. "
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    ABSTRACT: Birds of prey had a large home range and inhabit areas which are far away from human access so it is difficult to estimate their population. Kites (Milvus migrans) and crows (Corvus splendens) often gather in large communal roosts during migration at a site for food and breeding. The present study was done to estimate their population by Roost Count Method. Four sites were visited and population of kites and crows was estimated. It was found that 356 kites and 224 crows were present on an average at any roost. The soaring kites in the high skies and crows in the forenoon and afternoon sessions were more or less absent. In addition, these birds were less common on huge Garbage sites. Shockingly, it seems that like vultures, black kites and crows are on their way to elimination in Lahore.
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    • "Non-adult birds forage extensively over both the highlands and, to a lesser extent, the lowlands and may traverse the entire species' range within a few days (n  7). Adult Cape Vultures (n  2) forage predominantly within 15 km of breeding colonies, but foraging may extend up to 40 km from the colony (see also Jarvis et al. 1974; Robertson and Boshoff 1986; Brown and Piper 1988). "
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    ABSTRACT: Wind farms have been shown to cause bird mortality in many studies. Proposals for the development of wind farms in Lesotho, which is core habitat for small and declining populations of the regionally Endangered Bearded Vulture Gypaetus barbatus meridionalis and regionally and globally Vulnerable southern African endemic Cape Vulture Gyps coprotheres is therefore of concern. We use satellite tracking data to demonstrate that southern African Bearded Vultures spend the majority of their time foraging in landscape zones typically chosen for wind farm development (active selection for ridge tops and upper slopes), and that both species generally fly at heights within the rotor-sweep of a typical, modern wind turbine. We constructed a population viability model using actual population data from the area presently being targeted by the wind energy industry, calibrated with actual data on local population trends, to assess the potential impact of two specific wind farm development proposals on the populations of both vulture species. Even under conservative assumptions, relatively small-scale wind farm development in the Lesotho Highlands is likely to result in accelerated population decline and extinction in both species. The only feasible mitigation is to move the development sites off the ridge tops and upper slopes.
    Ostrich - Journal of African Ornithology 05/2014; 85(1). DOI:10.2989/00306525.2014.913211 · 0.41 Impact Factor
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    • "coprotheres) (one was a possible G. africanus x G. coprotheres hybrid) based on MCPs from satellite tracking data in Namibia [20]. The foraging range estimates in our study are substantially larger than the estimate of 1940 km2 for a breeding colony of Cape vultures in the Western Cape Province of South Africa obtained from landowner questionnaires and radio-tracking data [41], and 9200 km2 for a Cape vulture population in the Drakensberg mountains obtained from re-sightings of marked individuals [42]. Comparisons with earlier studies are difficult, however, due to differences in environmental conditions and foraging ecology of the different study species, and the methods used, with continuous GPS tracking methods able to provide a much better representation of the vultures' movement patterns [27]. "
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    ABSTRACT: Vultures in the Gyps genus are declining globally. Multiple threats related to human activity have caused widespread declines of vulture populations in Africa, especially outside protected areas. Addressing such threats requires the estimation of foraging ranges yet such estimates are lacking, even for widespread (but declining) species such as the African white-backed vulture (Gyps africanus). We tracked six immature African white-backed vultures in South Africa using GPS-GSM units to study their movement patterns, their use of protected areas and the time they spent in the vicinity of supplementary feeding sites. All individuals foraged widely; their combined foraging ranges extended into six countries in southern Africa (mean (6 SE) minimum convex polygon area = 269,1036197,187 km 2) and three of the vultures travelled more than 900 km from the capture site. All six vultures spent the majority of their tracking periods outside protected areas. South African protected areas were very rarely visited whereas protected areas in northern Botswana and Zimbabwe were used more frequently. Two of the vultures visited supplementary feeding sites regularly, with consequent reduced ranging behaviour, suggesting that individuals could alter their foraging behaviour in response to such sites. We show that immature African white-backed vultures are capable of travelling throughout southern Africa, yet use protected areas to only a limited extent, making them susceptible to the full range of threats in the region. The standard approach of designating protected areas to conserve species is unlikely to ensure the protection of such wide-ranging species against threats in the wider landscape. Citation: Phipps WL, Willis SG, Wolter K, Naidoo V (2013) Foraging Ranges of Immature African White-Backed Vultures (Gyps africanus) and Their Use of Protected Areas in Southern Africa. PLoS ONE 8(1): e52813.
    PLoS ONE 01/2013; 8(1). DOI:10.1371/journal.pone.0052813 · 3.23 Impact Factor
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