October 2005
Populations of six West African vulture species have drastically declined over the last 30 years, according to the results of a survey in eight countries by Afrique Nature International (AfNat).
Vultures play a vital role as indicators of ecosystem health so the decline is particularly alarming, underscoring the critical state of the Guinean Forests of West Africa biodiversity hotspot.
Supported by the Critical Ecosystem Partnership Fund, the survey covered the populations of vultures that range over the hotspot, while focusing on their breeding grounds in northern Guinea, Ghana, and Togo.
The results tell a grim story: Apart from the hooded vulture (Necrosyrtes monachus), numbers of which are down 45 percent, vulture populations have plummeted around 95 percent on average in rural areas. Furthermore, a 42 percent average decrease in abundance was observed for all vulture species in the few protected areas in the region.
“The enormous decreases in abundance indices found in these surveys show that all vulture species of the West African subregion, whether they were previously abundant or uncommon, are in real decline," said Guy Rondeau, AfNat’s West African Raptor Center director.
Despite this, only one of the vulture species found in West Africa is classified on the IUCN Red List of Threatened Species and the threats facing them need to be urgently publicized, according to Rondeau.
The survey forms part of CEPF’s wider strategy of establishing a biodiversity monitoring system across the hotspot and AfNat will use the data to update the species Red List categories.
The exact causes of this swift, generalized decline are not yet known, but the many signs seem to point to unsustainable hunting and poison. Similar declines in Asian vulture populations have been caused by the use of diclofenac used to treat cattle and the team initiated enquiries as to whether this is also a factor in West Africa.
Yet, aside from their intrinsic value, the birds act as “Nature’s cleaners” by preventing the spread of disease from infected carcasses, so Afnat warns that their disappearance could be accompanied by an increase in epidemiological diseases.
The survey builds on the results of comparative raptor surveys carried out in the same area by Jean-Marc Thiollay of the French Muséum National d'Histoire Naturelle between 1969 and 1973 and again last year in Burkina Faso, Mali, and Niger.
The project also contributed to CEPF’s focus on strengthening the institutional capacity of local civil society groups in the hotspot, with two local ornithologists from Guinée Ecologie and Côte d'Ivoire’s SOS Forêts trained in raptor identification and monitoring techniques. Both NGOs participated in BirdLife International’s regional capacity building project funded in part by CEPF.
For more information, contact Guy Rondeau, West African Raptor Center director, Afrique Nature International, .