BEARDED VULTURE POPULATION AND HABITAT VIABILITY ...

Population and Habitat Viability Assessment: Bearded Vulture (Gypaetus barbatus)
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Food supply: The loss of natural ungulates, superior animal husbandry practices and
improved animal hygiene has lead to a reduction in the food supply and is considered by
some (e.g. Boshoff et al. 1983) to be the most serious cause of population decline and range
contraction. Food is hypothesised as a limiting resource in Lesotho (for the same reasons as
hypothesised by Boshoff et al. 1983, above) and also through the possible lowering of
stocking rates consequent on overgrazing (D. Allan, in litt.). It is thought that food may be a
limiting factor in parts of South Africa (S. Krüger, pers. comm.). In Lesotho, it is likely that
nearly all dead livestock is eaten by the owners of the beast (Maphisa 1997) or harvested by
shepherds and their attendant packs of feral dogs (S.E. Piper, pers. obs.). In the region
around the Lesotho Highlands Water Project supplementary fodder is provided, by way of
compensation to the local villagers and so there is a tendency to keep domestic livestock
closer to the villages and thus dead livestock are less available to be found first by vultures
(Maphisa 1997).
Poisons: An opposing view (e.g. Brown 1991) is that outside of the Western Cape there is an
adequate food supply but that the species is limited by the injudicious use of poisons. It has
been suggested that up to 70% of all Bearded Vulture mortalities are due to poisoning (Brown
1997a); poison is hypothesised as a serious cause of mortality in Lesotho (D. Allan, in litt.).
Three Bearded Vultures were poisoned in the Eastern Cape (Boshoff 1991) when eating from
a baited lamb carcass, set for Black-backed Jackals Canis mesomelas or some other ‘problem
animal’ (see also Brown 1991). A minimum of two Bearded Vultures were poisoned in the
period 1995-2002 and during this period there was a suspected increase in use of strychnine
in Lesotho (N. van Zijl, unpublished data, EWT-Poison Working Group, in litt.). No further
cases of poisoning have been recorded by the Poison Working Group since 2002 (T. Snow, in
litt.). In a study on the poisoning of game-birds it was estimated that only 14% of poisoning
incidents were reported and it is likely in Lesotho and other mountainous parts of the Bearded
Vulture’s range that the reporting rate will be much lower (T. Snow, in litt.).
‘Coyote Getters’: Two Bearded Vultures were recorded killed in the Fee State Province
(Colahan 1991; Colahan and Esterhuizen 1997).
Gin traps: A gin trap was used, at least once, to capture and kill a Bearded Vulture in the
Free State Province (Ambrose 1983; Colahan 1991; Colahan and Esterhuizen 1997). In 1980
a man was arrested in Lesotho having in his possession five Bearded Vulture skins, one Cape
Griffon Vulture skin and a skin of a Verreaux’s Eagle, caught using a gin trap (Ambrose 1983
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