Current view: Text account
Site description (2001 baseline):
Site location and context
Collywobbles is an ancestral vulture colony occurring along the cliffs of the convoluted gorge formed by the meandering mBashe river in the Idutywa District (former Transkei). The colony is situated c.5 km from the Collywobbles store. This colony has been in existence since at least the 1890s. The river, which has cut a deep broad gorge, lies 300 m below the surrounding plains.
See Box for key species. The number of
Gyps coprotheres at Collywobbles has fluctuated dramatically over the last 20 years. Approximately 200 pairs inhabited the cliffs in the late 1970s. Breeding numbers increased sharply in the early 1980s, rising to over 300 pairs, and then stabilized. The elevated total persisted until the end of the decade (at which time it was one of the largest colonies in the world). Numbers then decreased rapidly between 1989 and 1993 before fixing on lowered, more stable totals of 60–90 pairs per year. The vultures have nested on 13 separate cliffs—Main, mSikiti and Ledger cliffs support the largest numbers of breeding pairs and, together, they regularly represent up to 60% of all the breeding vultures at Collywobbles. Annual fluctuations in numbers of breeding birds may be more extreme at the other 10 cliffs.
Non-bird biodiversity: None known to BirdLife International.
Pressure/threats to key biodiversity
This colony is located in a region which has always been used by pastoralists, where stock densities are high and husbandry techniques traditional. However, trends in land-use patterns are shifting and it would appear that the vultures are responding to these changes. Until 1989 this colony of
Gyps coprotheres had been one of the largest and most successful in southern Africa, with over 800 birds (7% of the global population) present here at any one time. The dramatic reduction in vulture numbers was attributed to improved husbandry techniques and changes in pastoralist practices, including a reduction in livestock density, which has been a result of peri-urbanization and an abandonment of traditional lifestyles by rural residents. The vultures’ continued existence at this site is under severe threat. At the nests, adults that are disturbed, for even short periods, may lose their eggs or nestlings for that year. The period of greatest vulnerability extends from egg-laying in April (peak in May), through peak hatching in July to fledging by October/November.
Although vultures face many problems at their breeding sites, they also move considerable distances inland while foraging, and are exposed to a different suite of threats. Poisoned carcasses set for vermin, or more commonly by traditional practitioners for ‘muti’, or medicine, may be responsible for considerable numbers of vulture mortalities (hundreds can be killed in a single poisoning incident). In order to implement an effective awareness campaign that informs local land-users of the vultures and their significance, it is vital that the extent of the vultures’ foraging area be determined. The Vulture Monitoring Project of the Vulture Study Group counts nestlings at Collywobbles as a measure of the success of this population. It is important that the colony remains under constant monitoring.
Recommended citation
BirdLife International (2024) Important Bird Area factsheet: Colleywobbles Vulture Colony (South Africa). Downloaded from
https://datazone.birdlife.org/site/factsheet/colleywobbles-vulture-colony-iba-south-africa on 23/11/2024.