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It is a crisp, sunny winter morning on the cliffs of the Magaliesberg
mountains, some 50 kilometres from Johannesburg: a sulphurous haze of pollution
hangs in the valley. Suddenly, as the thermals gather strength, dozens of
vultures leave their nests and begin to circle and soar above the cliffs.
The daily search for food and places to bathe and roost has begun.

A few hundred years ago these enormous, majestic birds would have looked
down on savannas populated by herds of wild ungulates, and littered with
carcasses. But life is no longer so easy for Africa’s Cape griffon (Gyps
coprotheres), the best known of all the Old World vultures. Below them today
stretches a huge reservoir fringed by expensive weekend homes, and a network
of roads abuzz with cars and lorries. Below, too, are the towers of a nuclear
power plant, crop fields sporting pesticide sprinklers and the long, low
sheds of high-technology factory farms. On weekends, the vultures even have
to share their airspace with hang-gliders.

Large chunks of the Cape griffon’s former range – which at the turn
of the century covered most of southern Africa – have been replaced by dense
forest plantations where anything that dies lies hidden among the trees,
and by vast acreages of sugar, wheat, maize and sunflowers. As a result,
Cape griffons no longer circle Table Mountain nor darken the skies of the
great grasslands of the Karoo, as they did when the first Europeans arrived
in the Cape in the middle of the 17th century.

That matters, say ecologists – and for more than sentimental reasons.
Large scavengers like the Cape griffon are excellent monitors of the general
health of an ecosystem, they say. Weaken the base of the food chain with
chemical pesticides and intensive farming, and the most highly visible animals
at the top respond by dying off. ‘When the countryside has become unsafe
for vultures, it’s become unsafe for people too,’ says Steven Piper, a
statistics expert at the University of Natal, who has just completed a doctoral
thesis on the demography of Cape griffons.

But this gloomy diagnosis has yet to stir government agricultural experts.
Indeed, some biologists even seem resigned to its inevitability. ‘A lot
of people, including big name scientists, have said that vultures are relics
of the Pleistocene era and have no future in a man-dominated environment,’
says John Ledger, director of the Endangered Wildlife Trust, a southern
African conservation group. ‘But we strongly disagree.’

Conservationists in South Africa are now waiting anxiously to see if
the political upheavals will lead to a change of heart and policy. ‘The
decisions we make about land use in the New South Africa will be crucial
for the vultures,’ says Piper. ‘More or less pastoral land will mean more
or less vultures. And rules about how we dispose of (animal) carcasses and
control the use of poisons (by farmers) will determine whether the Cape
griffon has a future or not.’

In the meantime, however, all is not lost. The main problem facing the
Cape griffon is a shortage of food. On this front at least, Ledger and like-minded
individuals have managed to buy some time for these wild scavengers with
an unlikely chain of specially designed restaurants. The conservationists
have also persuaded many of South Africa’s farmers to think twice before
leaving out meat laced with poisons. Many conservationists consider it a
minor miracle of adaptibility that the Cape griffon has survived at all.

With a wing span of about 2.5 metres, the Cape griffon is the second
largest African vulture after the lappet faced vulture (Torgos tracheliotos).
But it holds the record for weight (around 9 kilograms), and has the distinction
of being the most thoroughly studied of the Old World vultures. In 1948
the Cape griffon was the first bird species in the whole of Africa to be
ringed – an operation that involved mountaineers scaling the cliffs to
grapple with feisty fledglings that shat and spat in self-defence. Over
the decades, the recovery of these marked birds has produced a wealth of
detailed insights into their rates of survival and reproduction. It is
now clear just how precarious the Cape griffons’ position is.

Vulture researchers reckon there are around 4400 breeding pairs left,
and about 12 000 birds in total. The largest colonies are at the Magaliesberg
and three other cliff sites in the Transvaal, and in parts of the Drakensberg
massif that covers Lesotho, the Transkei, Natal and the Orange Free State.
A few smaller populations breed on the fringes of this mountain range in
Botswana and Namibia.

From observing the breeding patterns, Piper calculates that it takes
an adult bird about twenty years to replace itself, despite the fact that
the vast majority of birds breed almost every year. Why such painfully slow
reproduction? One reason is infant mortality, says Piper. Nearly half of
all Cape griffon nestlings die in their first year, and only about 16 per
cent make it into adult life. And Cape griffons can lay only one egg a year
because they find it impossible to feed more than one chick.

Ringing has produced cultural as well as scientific results. It brought
people and vultures into intimate contact and won many hearts for a bird
generally viewed with distaste, if not revulsion, by white people. It’s
a prejudice with a long history, says Ledger, who cites the Bible as a case
in point. References to vultures abounded in the original Hebrew, he notes.
But the translators responsible for the St James version converted them
into eagles. ‘Their prejudice did not allow them to accept that a bird as
loathsome as the vulture should appear in the Bible.

Making a meal of it

In 1973, Ledger and his colleague Peter Mundy started the Vulture Study
Group – an organisation that quickly grew into an alliance of scientists
and amateurs dedicated to the study and conservation of vultures. Today
it has over 400 members. One of the VSG’s first initiatives was to set up
‘vulture restaurants’ – specially selected and fenced sites at which carcasses
can be regularly deposited to help the scavengers feed their chicks. There
is no shortage of carcasses: thousands of farm animals die each year in
South Africa. But without the efforts of the VSG these would be burnt in
the interests of disease control.

Feeding vultures is not the only function of the restaurants. While
clambering around the cliff ledges of the Magaliesberg colony in the mid-1970s,
ringers noticed that many nests contained bits of glass, china, aluminium
ring-pulls and plastic. They also observed that a high proportion of fledglings
had deformed wings that prevented them from ever flying.

Ledger and Mundy believed the two phenomena were probably linked. They
reasoned that the osteodystrophy in chicks was caused by a lack of calcium
in their diet. In a natural environment, vultures feed on carcasses alongside
other meat eaters such as spotted hyenas, and they rely on the bone-cracking
skills of the hyena to produce splinters and fragments of bone suitable
for their chicks. But the predatory spotted hyena has been exterminated
from most farmland and there is no other creature capable of crunching skeletons.

The VSG believes the birds collect junk as a substitute for bone fragments.
Chicks have been found with their crops choked with rubbish. Sometimes the
indigestible load has become so heavy that the chick has fallen to its death
from the nest. ‘You sometimes just find a little pile of bones and this
huge collection of rubbish all together at the bottom of a cliff,’ says
Piper.

So besides putting out carcasses, vul-ture restaurateurs also smash
bones for the birds – an activity that has drama-tically reduced the incidence
of osteo-dystrophy. Before the restaurants, 16.7 per cent of birds in the
Magaliesberg colony suffered from the disease. By 1983 this figure had dropped
to 3.7 per cent.

Today there are over 100 privately run vulture restaurants, and sometimes
the menu is exotic. Race horses, Brahmin bulls and recently an elephant
that trampled a tourist have all provided meals for the vultures. But the
most bizarre meal was that of a South African farmer, Mickey Lindbergh,
who in 1987 committed suicide by shooting himself in his vulture restaurant.
His intentions were clear, for he first removed his clothes and left them
folded some distance away so that the wary scavengers would not be scared
off by cloth flapping in the wind.

Lack of suitable food is the ultimate limiting factor on the vulture
population. But the VSG has identified four other major causes of unnatural
death among Cape griffons: poisoning, drowning, electrocution and harassment
– small boys tumbling rocks on to nesting cliffs, for example, or people
using birds for target practice. The poisoning results from the fact that
Africa’s white farmers wage constant war against the black-backed jackal
and the caracal, which they see as threats to livestock, habitually putting
out carcasses laced with strychnine or the like. This tactic kills around
100 ‘innocent’ animals for every one target animal, according to the VSG.
They reckon that between 150 and 200 vultures die in this way each year.

There have also been some spectacular poisonings connected with muti
(traditional medicine). Many black people believe vultures are clairvoyant
because of their extraordinary power to gather out of the blue at the site
of a kill. Vulture parts are highly valued by traditional healers, and muti
hunters have been caught in the sacrosanct Kruger National Park cutting
the heads off birds lying dead beside poisoned carcasses. Traditional medicine
is big business today in populous South Africa.

The electrocution problem was first noticed about 20 years ago. South
Africa produces about 60 per cent of all electricity on the African continent,
mostly in giant power stations located in the eastern Transvaal. The huge
network of transmission towers and electricity poles used to distribute
it provide ideal perches for vultures, and have allowed the birds to range
into treeless and cragless areas that would otherwise be unsuitable. But
certain structures proved fatal to the Cape griffon with its huge wingspan.
When they tried to land on the crossbars of the ‘kite construction’ towers
of the western Transvaal used to carry 88 kilovolts, birds frequently made
contact between the perch and the live wire and died in a blinding flash.

Often this disrupted the power supply at the same time. So when Ledger
approached the electricity utility company, Eskom, in the early 1980s, it
was eager to cooperate. Eskom modified the design of the power lines to
be vulture-friendly, putting a large perch on top of the kite structure.
In 1985, whitebacked vultures (Pseudogyps africanis) were discovered nesting
on 132-kilovolt transmission towers in the northern Cape, and today groups
of as many as 20 Cape griffons can be seen sitting on these high-voltage
towers.

Drowning by numbers

Drowning is estimated to kill about 9 per cent of young birds each year.
The biggest danger comes from concrete water tanks on farms. ‘Vultures sit
around the edge,’ explains Piper. ‘One will jump in to bathe, not realising
it’s too deep and then start flapping in panic. When the others see the
flapping (which is what they do at a carcass) they all jump in. You sometimes
get as many as seventy birds in a tank at once and half of them will drown.’
The VSG is trying to encourage farmers to put floating structures in the
tanks so the vultures can clamber to safety.

The VSG sees educating farmers as one of the keys to vulture conservation.
Many have been won over to the cause. But the hard cases who refuse to believe
that vultures do not kill lambs or spread diseases like anthrax can destroy
all the gains. ‘It’s a truism that birds cover an enormous range and you
only need one farmer in a district putting out poisoned carcasses to poison
all the birds within 200 kilometres,’ says Ledger. ‘For that reason, vulture
conservation cannot be a 99 per cent thing. There’s got to be 100 per cent
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Will the Cape griffon still be soaring above the Magaliesberg cliffs
at the end of the 21st century? Nobody knows, but optimists point to times
when the bird has thrived in the company of humans. ‘The Cape griffon population
probably rose to great heights at the end of the 19th century,’ says Piper.
At that time an epidemic of rinderpest had just swept across Africa, killing
up to 90 per cent of the cattle in some areas. And then there was colonial
strife. As Piper points out, ‘There were great losses of horses, mules and
men in the Anglo-Boer war.’

Sue Armstrong is a freelance science writer based in South Africa.