By John Ikani
Inbreeding within hooded vulture populations in Ghana and South Africa poses a significant threat to their survival, according to a new study.
Despite vast differences in population size between the two countries, both face the same risks due to limited genetic diversity.
This highlights the urgent need to protect hooded vultures from hunting and habitat loss.
Researchers studied molted feathers from vulture nests in both Ghana, where the species is considered highly endangered due to a sharp population decline but remains currently abundant, and South Africa, where only an estimated 100-200 mature adults remain, primarily in Kruger National Park.
Even with contrasting population sizes, birds in both regions displayed high levels of inbreeding and low genetic diversity – a concerning finding for the researchers.
The study indicates that while the number of hooded vultures in South Africa is decreasing, there’s still hope for recovery. “It still does have some unique genetic components which are important to conserve,” said study co-author Sandi Willows-Munro, an associate professor at the University of KwaZulu-Natal in South Africa.
Hooded vultures play a vital role in the ecosystem of both countries by scavenging carcasses, thereby eliminating diseases and potentially harmful bacteria. Low genetic diversity makes these populations vulnerable to threats like disease outbreaks and less adaptable to environmental change.
Researchers initially believed that Ghana’s relatively large hooded vulture population would be more genetically diverse than its South African counterpart. However, according to Willows-Munro, their findings indicate that the West African population’s genetic health is “not doing so well.” This leaves them highly susceptible to disease outbreaks, such as avian flu.
The cause of such high inbreeding levels in Ghana’s hooded vulture population remains unclear. One theory, Willows-Munro suggests, is that the species may have experienced a genetic bottleneck long ago due to a dramatic population decline caused by climatic shifts, transforming some grasslands into forests.
It might also be a more recent phenomenon caused by human activities. The research team continues to investigate this, hoping to shed light on it in future studies.
“The key takeaway is that you can’t simply count the number of vultures in a population and assume it’s healthy,” Willows-Munro said.
The consequences of losing vultures
Hooded vultures are classified as critically endangered and are experiencing a significant population decline across their range. Like many other African vulture species, they face various threats, including habitat loss, poisoning, collisions with power lines, and hunting for “belief-based use.”
These birds were once widespread in Ghana, said study co-author Justus Deikumah, a conservation biologist with the University of Cape Coast in Ghana and West Africa representative for the vulture specialist group at the IUCN, the global wildlife conservation authority. Their numbers have dwindled in recent decades due to various pressures, including their use in traditional medicine. Conservationists have recently launched a multi-year action plan specifically targeting this threat.
In South Africa, vultures are under pressure from both intentional and unintentional poisoning, with their parts also used in traditional medicine. A 2021 study found that a single association of traditional health practitioners harvested up to 800 vultures annually for such purposes in the Kruger to Canyons Biosphere Region.
Johannes Masopa Mphelo, a sangoma or traditional medicine practitioner and president of the Traditional Healers Association of Southern Africa, believes the use of vulture parts stems from a misunderstanding of traditional medicine. “There is no way we can use vultures to heal or to generate medicine,” he said. “We’re only using herbs from the ground and only using parts from the trees.”
Mphelo, who is also a police officer, said that in his home region of Limpopo province, South Africa, people poison the birds believing their parts can bring worldly success. “There is no such benefit of becoming rich or healing people with vulture parts,” he said. “It’s all a lie.”
He believes that losing vultures will harm South African communities. “If we kill vultures, what is it that we are going to have in the future? Because our children and our grandchildren will never know the vulture,” Mphelo said.
The decline in vulture populations may also have health implications for those communities. Vultures clean up landscapes by scavenging carcasses, thereby removing harmful bacteria and diseases. A paper published earlier this year linked a sharp decline of vulture populations in India to the deaths of more than 500,000 people between 2000 and 2005. These findings are cause for concern in Africa too, say experts such as Deikumah.
As vulture numbers dwindle, other scavengers like feral dogs can increase. Unlike vultures, they can act as disease reservoirs, potentially spreading rabies and other diseases. Research in Ethiopia, for instance, found that as vulture numbers visiting abattoirs decreased, dog numbers doubled, potentially increasing the risk of rabies for local communities.
While studies directly linking vulture declines to disease spread in Africa are limited, experts say such scenarios could easily occur.
“It’s crucial that we preserve these species because they provide us with such an important sanitation service,” Willows-Munro said. “In South Africa, where we have extensive vaccination campaigns against rabies, we still have a significant problem. In other countries with less-established vaccination programs, I can imagine the impact will be even worse.”
Reducing the threats
Researchers suggest several steps governments and communities could take to protect vultures and address the declining genetic diversity in South Africa and Ghana. These include captive breeding, reintroductions, supplementary feeding, GPS tracking to understand population movements better, and ongoing genetic monitoring.
André Botha, co-chair of the IUCN’s Vulture Specialist Group, believes the study could stimulate conservation action. “It highlights the need for conservation action in the peripheral populations, or the edge populations, within South Africa,” he told Mongabay.
The study also emphasizes the need for far greater protection for the birds in Ghana, and West Africa in general, where threats are high.
Mphelo suggests that raising awareness about the precarious situation of the birds in South Africa could help combat the practice of hunting them for traditional medicine.
“People need education. They need to be educated about the importance of vultures for nature,” he said. “Because vultures have also got a right to life.”
