Can we learn to love vultures?
Vultures have suffered something of an image problem over the years. Eating the bodies of dead animals has never attracted us to them. But now a project - supported by the Duke and Duchess of Cambridge - is trying to turn round how we think about the birds, which are facing new threats, as the BBC's Kevin Bishop reports from Johannesburg.
Cape vultures swoop down from South Africa's blue spring sky over the Magaliesberg Cliffs.
Dozens skim over the dry, brown grassland to a "vulture restaurant".
A carcass has been laid out in the sun, flies buzzing around it and crows and egrets pecking at its skin. Slowly, one brave female gingerly approaches.
Step by step, each gently-landed claw accompanied by a cautious scan of the area for danger.
They take their time - an hour or more passes before they feel confident.
But once one vulture takes her first snatches of flesh, the others pounce. A feeding-frenzy ensues.
Each vulture pushing and squabbling its way to enough food to satisfy itself - and the chick waiting back on the cliffs.
We are at VulPro, on the outskirts of Haartebeesport, an hour's drive from Johannesburg.
It is a nature conservancy dedicated to a species that has got a reputation as the least cute, least huggable of all animals.
But Kerri Wolter, the head of VulPro, believes that the role that vultures play in nature - clearing away disease-ridden flesh - is crucial:
"We've got to lift the profile of vulture species to the same level as rhino, we've got to get people to acknowledge they are important."
The cape vulture is seen by the International Union for the Conservation of Nature's (IUCN) Red List as being "vulnerable".
Conservationists here fear they will soon join the African white-backed vulture, which is now seen as "endangered" with numbers decreasing by 90% in West Africa.
IUCN has seen a fall of more than 1,500 mating pairs of cape vultures in the last 20 years.
They are only now to be found in Botswana and South Africa, having become recently extinct in Namibia.
They face threats from electrocutions and collisions with electrical structures, land-use changes, a decrease in food availability and exposure to toxic veterinary drugs.
But the biggest danger is more sinister.
As the poaching of rhinos and elephants in southern Africa increases every year - more than 600 South African rhinos poached in 2013 to date - vultures are the unsuspecting victims.
The poachers are eager not to flag up their presence to game wardens.
So in some cases they have begun to poison the carcass of the animal they have just killed for its horn or tusks.
The vultures swoop in for their feed, unaware that the flesh is laced with a killer.
Ms Wolter says the stakes are high: "All you need is for one poisoned rhino, or one poisoned elephant, and you wipe out 600 vultures.
"However, during breeding season, it's not only the 600 vultures who consume that carcass. It's potentially their chicks as well.
"So you're looking at 1,200 birds at one poisoning incident."
And the threat isn't just to the birds.
A lifeline for humans?
In Asia, vulture numbers have declined by 99.9% in the last quarter of a century, according to the UK's Royal Society for the Protection of Birds (RSPB). Experience from there shows the danger to humans.
"Rotting carcasses were still lying in feeding sites, no vultures to consume them," Ms Wolter says.
"There were feral dogs, which carry rabies. Kids were playing in those sites and were bitten by those dogs."
As we watch them return to their nests high on the cliffs above us, Andre Botha, head of the raptor programme at the Endangered Wildlife Trust, underlines this fear:
"To put it simply, in Asia, when vultures declined at such an alarming rate in the 1990s up until now, people talked about the Asian vulture crisis. But I think in Africa we can talk about the African vulture catastrophe.
"The rate of decline and the impact we are having on vultures is such that many birds will disappear from the landscape of Africa within the next 30 to 40 years."
Back at VulPro, Ms Wolter is feeding a young chick she has named PJ.
She is hoping he'll be the poster boy for a new approach to the way we think about vultures.
And she is hoping that being put forward for an award by the Tusk Trust and its patrons Prince William and Princess Kate will help the cause.
"Maybe through the award nomination, through the Tusk Trust, we can get support from..." she smiles wryly "the Tusk patron….Maybe through Royal support it'll hopefully make the species look a little more important than they are now."
And why does she love vultures?
"I guess its because I understand them, I feel their struggle for survival in a world unable to appreciate nor understand their importance," she says.
"They are nature's true beauty which completes the circle of life and keeps us, our world, safer from the spread of unnecessary diseases."