The African vulture crisis is an ongoing population decline in several Old World vulture species across Africa. Steep population declines have been reported from many locations across the continent since the early 2000s. The causes are mainly poisoning from baited animal carcasses, and the illegal trade in vulture body parts for traditional medicine.[1] Available data suggest that the African vulture crisis may be similar in scale to the Indian vulture crisis, but more protracted and less well documented.
thumb|right|Several vultures may gather to feed on a large carcass. Poisoning may kill hundreds
Animal carcasses may be poisoned with toxic pesticide. This may be from deliberate targeting of vultures -- for example, poachers of elephants and rhinos will target vultures to eliminate their tell-tale overhead circling that might expose their illegal activities. Carcasses are also poisoned to kill carnivores blamed for predation of livestock, herbivores blamed for crop destruction[2] and to control feral dog numbers.
Vultures are particularly vulnerable to poisoning because of their foraging behaviors and life history traits. They are obligate scavengers that primarily consume animal carcasses and waste products. Most vulture species forage in large groups, so many individual birds may be poisoned by a single carcass.[3] Even if a poisoned carcass does not kill vultures it can have a harmful effect. Sublethal exposure can affect their reproductive success, behavior, physical characteristics, and immune response.[4] Their long life spans and high trophic level also make them vulnerable to bioaccumulation of poisons over time.
Vulture body parts are used in some cultures to treat physical and mental illnesses. The prices of vulture meat and body parts have been rising, possibly due to an increased demand for these products or a reduced supply of vultures.[5] The African Vulture trade for belief uses varies in importance across the continent with different African cultures participating or not depending on the value of body parts and meat to their traditional medicinal practices. The current level of trade is not sustainable and is contributing to the decline of vulture populations.[6]
Vulture collisions with energy infrastructure and electrocution are relatively common, especially in southern and northern Africa. Efforts to meet United Nations Sustainable Development Goals have led to expansion of electrification programs. However, these do not always implement bird-safe designs that would limit the risks of electrocution and collision.[7]
Other threats that contribute to the decline in African vulture populations include habitat degradation and fragmentation, disturbance of nest sites, declines in vulture food supply, and bushmeat consumption by humans. Vulture deaths have also been caused by them visiting wells to drink then becoming waterlogged and drowning. In one incident in Morocco, 15 Eurasian griffons drowned in a well.[8]
Excluding vagrants, three vulture species still exist in North Africa: the griffon vulture, lammergeier, and Egyptian vulture. Two other species (the cinereous vulture and lappet-faced vulture) have now died out from the region.[9]
The Egyptian vulture is found across North Africa, while the Eurasian griffon is restricted to the Atlas Mountains. The lammergeier is eradicated from the region except Morocco, where it is considered critically endangered.[10]
The most affected species is the Eurasian griffon,[11] though it is apparently common in much of Europe and Asia. Many poisonings in the region are attributed to the use of strychnine, which is heavily regulated by the Moroccan government.[12]
Seven vulture species live in West African countries: the Egyptian vulture, hooded vulture, lappet-faced vulture, palm-nut vulture, Rüppell's vulture, white-backed vulture and white-headed vulture.[13]
West Africa saw some of the largest decreases in vulture numbers, with up to 61% of vultures inside parks and 70% outside parks disappearing in the 30 years between 1970 and 2000.[14] Some populations have declined by almost 97%.[15] In 2020, around 50 hooded vultures were poisoned in Gambia, and between September 2019 and March 2020, 2000 were killed in Guinea-Bissau for traditional medicine. Conservation programs were initiated in these countries and in Senegal, surveying the vulture populations and raising public awareness.
thumb|left|The endemic cape vulture
Southern Africa has the highest species diversity of vultures in the continent, comprising eight species which are the aforementioned Egyptian vulture, hooded vulture, white-backed vulture, white-headed vulture, Rüppell's griffon vulture, lappet-faced vulture, palmnut vulture and the endemic Cape Vulture.
Whilst conservation action has been taking place in the region, [16] the sporadic nature of poisonings and their large death count have dealt heavy blows to vultures in the region.
A recent incident in Kruger National Park involved the poisoned carcass of an African buffalo somewhere in mid-August 2022. It was estimated that 104 White-backed vultures were fatally poisoned, while 20 were harmed. A hyena had also succumbed from the poisoning.[17] It was believed that the poisoning was intentional to collect vulture parts. Currently, the number of white-backed vultures sits at about 7,500 individuals, down from a population that numbered tens of thousands.[18]
An environmental catastrophe effectively occurred in the Chobe National Park, Botswana in 2019, involving the carcasses of three poisoned African bush elephants. A total 537 vultures perished, 468 white-backed vultures, 28 hooded vultures, 17 white-headed vultures, 14 lappet-faced vultures, and 10 cape vultures. Furthermore, 2 tawny eagles succumbed to the poison. For such slow-breeding and long-lived birds, this was a very heavy blow to their population and a major setback to any conservation efforts.
Vultures play an essential ecological role in Africa. As a primary scavenger they contribute to the destruction of harmful pathogens and removal of decaying corpses form the environment, which may limit water contamination and the spread of disease from animal carcasses.[19] Falls in vulture numbers in India led to increased numbers of feral dogs and increased rabies incidence,[20] showing a potential threat for human health in Africa.
| Image | Common name | Binomial name | Region | 2006 IUCN conservation status | 2021 IUCN conservation status | Population trends | ||
|---|---|---|---|---|---|---|---|---|
| Hooded vulture | Necrosyrtes monachus | Sub-Saharan Africa | align=center style="background: #006666" | [21] | align=center style="background:#cb3331" | [22] | Range-wide declines of 68-79%, several population crashes in west Africa have exceeded 80% declines. | |
| Rüppell's vulture | Gyps ruppellii | Sub-saharan Africa and Spain | align=center style="background: #006666" | [23] | align=center style="background:#cb3331" | [24] | Has had the worst range-wide declines, between 85-98% however is more secure in The Gambia and Maasai Mara | |
| White-backed vulture | Gyps africanus | Sub-Saharan Africa | align=center style="background: #006666" | [25] | align=center style="background:#cb3331" | [26] | Declined by 63-89% during the last three generations. Though the most common African vulture, it has suffered the most casualties during the crisis | |
| Cape vulture | Gyps coprotheres | Southern Africa | align=center style="background: #cbcc02" | [27] | align=center style="background: #cbcc02" | [28] | Declined by 60-70% from 1992 to 2007, however there have been recent increases in some breeding populations | |
| Lappet-faced vulture | Torgos tracheliotos | Sub-Saharan Africa and Arabia | align=center style="background: #cbcc02" | [29] | align=center style="background: #cc6402" | [30] | Declined by 67-80% over the last three generations in Africa. Arabian populations appear to be stable. | |
| White-headed vulture | Trigonoceps occipitalis | Sub-Saharan Africa | align=center style="background: #006666" | [31] | align=center style="background:#cb3331" | [32] | Declined by 60-75% throughout its range, with the worst in Botswana reaching an overall population crash with 87% lost. | |
| Egyptian vulture | Neophron percnopterus | Afro-Eurasia | align=center style="background: #cc6402" | [33] | align=center style="background: #cc6402" | [34] | 91% declines in Africa during the last three generations, about 10% in Europe, stable in the southern Middle East. The biggest declines were recorded in India, owing to the Indian vulture crisis | |
| Eurasian griffon vulture | Gyps fulvus | Europe, Asia, Morocco, and Algeria | align=center style="background: #006666" | [35] | align=center style="background: #006666" | [36] | ||
| Lammergeier | Gypaetus barbatus | Afro-Eurasia | align=center style="background: #006666" | [37] | align=center style="background: #0097a0" | [38] | 30% declines across its range. European populations are increasing however Asian populations have suffered heavily | |