Since 2015, four of the eight species of vultures found in Kenya have been listed as critically endangered by the International Union of Conservation of Nature (IUCN). This means they are one step short of becoming extinct.
High on the cliffs of Kwenia, 95km south of Nairobi, lives a colony of one of the Ruppell's vulture.
The estimated global population of Ruppell's vulture is 22,000.
"Ruppell's vultures breed in steep cliffs," said Dr Darcy Ogada of The Peregrine Fund, a raptor specialist for over two decades. "Any disturbance and they leave, like it happened at Hell's Gate."
Kwenia is one of the few sites in the world where the vultures breed. But now, the critical nesting colony will be heavily impacted by a proposed wind farm to be constructed across a major migratory flight path for birds.
By 11am, most of the vultures fly off to the Maasai Mara and the Athi-Kapiti plains, to scavenge on carrion and bring back food for their young.
These vultures are one of the largest species found in East and central Africa, but their populations are declining fast.
Initially it was due to habitat loss, poisoning and in some places to use in witch-craft.
Now it's the proposed wind farms and associated power lines as Kenya seeks to develop clean, green renewable energy.
Wind farms can be placed at inappropriate sites, like in the flight paths of birds. The rotating blades of the turbines need the wind to power them, as do raptors and migratory birds that fly to Africa to escape the winter in Europe and Asia.
Path for birds
The Rift Valley is a major path for birds of many species. Tracking units fitted on vultures within 25km of Kwenia show them flying at turbine height, placing them at high risk of being cut up by the rotating blades.
"Every single bird that was tagged in the Mara between 2009 and 2011," says Ogada "used the flyway. Of the 14 Ruppell's vultures tagged, 50 per cent fly in the area of the proposed wind farm."
High on the cliffs of Kwenia, 95km south of Nairobi, lives a colony of one of the Ruppell's vulture. Kwenia is one of the few sites in the world where the vultures breed but it is now threatened by a proposed wind farm to be constructed across a major migratory flight path for birds. PHOTO| MUNIR VIRANI
In addition, the African White-backed Vulture, also listed as critically endangered also lives in the vicinity of the proposed wind farm site.
It is recommended that a site must be more than 30km away, but the proposed wind farm is less than 15km from Kwenia's cliffs.
In their defence, the executors of the required environmental impact assessment say that it was carried out before the vultures were listed as critically endangered, and that the EIA was unaware of the habitats for wildlife like Kwenia.
The developers of the proposed wind farm, Kipeto Wind Farm, say it will not be moved.
The mitigation methods are that the turbines will be shut-down in less than five minutes of the approaching birds.
"The science behind that seems to work quite well, with migratory birds moving at a known time," said Dr Munir Virani, also of The Peregrine Fund, who was the first to highlight the rapid decline of vulture populations in Kenya over the past two decades -- in some species by more than 90 per cent. Gregarious, vultures are vital to scavenge on carcasses of livestock and wildlife and stop the spread of diseases from decaying flesh
"But it's not economical for the developer to shut down on demand because the vultures are resident there, moving all day, all the time. It would be too costly for the developer and for the birds, with a lot of potential for collision," Munir added.
The financer of the project International Finance Corporation -- an arm of the World Bank -- is obligated to show the net gain for the critically endangered species. Failure to do so could put their organisation in disrepute.
Minimal impact"The conservation community is not against wind energy. We embrace it," said Munir. "But project sites have to be identified using available scientific tools and expertise so that the impact on wildlife is minimal. The government of Kenya should showcase to the world that renewable energy projects can be sustainable without putting at risk our natural wildlife heritage."
"It's inevitable that Africa's landscape is going to change," Munir added. "But how it changes needs guidance.
"Development needs policy frameworks based on science because there are other prospectors looking at Kwenia and other places. But development is happening faster than policies."
Projects such as the Turkana wind farm and the standard gauge railway passing through national parks, which are supposed to be protected areas for biodiversity, have been executed in much the same way as the current proposed wind farm -- without comprehensive involvement of all stakeholders.
"The EIA is a good tool," said Serah Munguti, East Africa Natural History Society's advocacy manager. "But the issue is that you hardly see any that says the project should not continue. The consultant is paid by the developer, and so even when the project has such severe outcomes, it's still proposed.
"In Kenya, EIAs have not safeguarded biological diversity. What we need is a holistic approach to get out of this hole."
Conservationists agree that a new environmental map of Kenya is needed for areas suitable for wind farms and other mega-development projects -- and then their feasibility checked against biodiversity hotspots.
"We have an obligation to conserve biodiversity," added Munguti. "It doesn't belong to a few, but to all. We depend on it for the medicine we need, food we eat, the clothes we wear, the places we live in.
"That is why the governments of the world came together for the Convention on Biological Diversity, which was adopted in 1992 in Nairobi. Biological diversity is our heritage, and Kenya is a signatory to the CBD and therefore obligated to conserve biological diversity. We cannot kill everything in our generation and leave nothing for future generations."