Vultures in Namibia
In May 1995 a farmer near Usakos on the edge of the Namib desert poisoned 94 vultures, 86 of which were Lappetfaced Vultures, the remainder Whitebacked Vultures, with a single poison-baited carcass. The farmer claimed that these vultures had killed “scores” of his newly-born Dorper lambs, thus believing that he was justified in killing these supposed predators. Incidents such as this are relatively uncommon in that most vultures, and other innocent scavengers, are usually killed at poison-baited carcasses targeting “problem” animals — jackals, hyaenas and Caracal.
This most unfortunate massacre of vultures, representing as much as 80 percent of the Namib Naukluft Park’s (then) breeding population of Lappetfaced Vultures, is one of the most recent events in a long history of persecution of vultures and other innocent scavengers on commercial farms in southern Africa.
Stories of vultures preying on domestic livestock have been reported frequently over the years; indeed, these stories are deeply entrenched in sheep farming society. However, none of these supposed events have ever been properly documented or verified. In cases where the “facts” have been followed up, a misinterpretation of circumstantial events has invariably led to such reports. Although probably sharing a common ancestry with eagles in the distant past, vultures are specialised scavengers, and are unable to kill prey! Unlike eagles, which invariably kill prey with their powerful talons, vultures have very weak feet, and are thus unable to kill. Admittedly they have fearsome beaks, and long muscular necks, but these anatomical features are key to their ability to strip and tear meat and viscera from carcasses.
Vultures and other scavengers play a very important role in clearing the veldt of carcasses. By rapidly consuming the remains of dead animals, vultures prevent these carcasses from serving as hosts to diseases such as blowfly and anthrax. Importantly, with the exception of the almost-extinct Egyptian Vulture, vultures depend entirelyon carrion for food. Vultures and other scavengers have adapted to the task of locating and feeding on carcasses of mammals. Most of these are animals that have died of natural causes, but vultures also regularly eat the remains of predator kills. Due to the unpredictable nature of their food supply, they often fly great distances in search of carcasses.
Lappetfaced Vultures are probably (or at least used to be) the commonest vulture of the Namib area. These massive vultures, the largest in Africa, are unmistakable in adult plumage. Black, with distinctive white “trousers” and a white-streaked chest, the adult is able to flush its face a deep red when excited. It is notable that a single adult is easily able to dominate any number of other vultures at a carcass, and has no trouble chasing a solitary jackal from its kill. Adults are usually seen in pairs, but the species can be quite gregarious at waterholes and carcasses. Their diet includes a large proportion of small animal carrion, another “fact” used as circumstantial evidence of their supposed predatorial habits. This is nonsense; it simply indicates their proficiency at locating carcasses, irrespective of size. Lappetfaced Vultures make large stick-platform nests in the crowns of thorntrees; in the Namib-Naukluft park such trees are restricted to the wadis of the floodplains. Like most other vultures in Namibia, they lay a single egg, rarely two, during the period May to July. Following an incubation period of some 56 days, the chick hatches. With one parent continually in attendance, the other parent foraging for food, the chick grows rapidly in the first 60 days on the nest; they gain adult weight of seven kilograms by 90 days of age, and leave the nest when they are four months old. For some time after fledging, the juvenile remains dependant on its parents for food, but will eventually have dispersed by the time its parent initiate breeding again in the following year. Immature birds wander over great distances, but it appears that they eventually return to their natal area to breed, at an age of six years or older.
The Cape Vulture or Griffon, once widespread in Namibia, is now virtually extinct, with only three or four breeding pairs left at the only remaining breeding colony of this species in Namibia — the Waterberg Plateau Park. The Waterberg Plateau Park colony was extirpated as a result of the widespread abuse of poisons in farmers’ war against problem animals. Breeding colonies of Cape Vultures elsewhere in Namibia, such as the huge colony at Rostockberg on the edge of the Namib, died out in the sixties and seventies. Far more gregarious in its foraging behaviour than other vulture species, the Cape Vulture is particularly prone to large-scale massacre by poison. Fortunately, this southern African endemic is still relatively common in some parts of South Africa, even though it has the smallest distribution of any vulture in Africa. More has been written about this vulture than any other African vulture, and it has also attracted the most conservation attention. Among a group of Whitebacked Vultures, an adult Cape Vulture, with its markedly larger head, long bluish neck, yellow eye and overall paler plumage, sticks out clearly. On its own, though, the species is often misidentified as a Whitebacked Vulture. Like all griffon vultures, the Cape Vulture breeds in colonies on the ledges of high cliffs. The largest colony is at Groothoek (Kransberg) in the western Transvaal, South Africa, where almost 1,000 pairs are distributed along five kilometres of cliff. Far heavier than Lappetfaced Vultures, the Cape vulture relies on prevailing air currents associated with mountains to fly, and will generally not forage before ambient temperatures have caused the development of thermals which allow them to glide over considerable distances. Like Lappetfaced Vultures, Cape Vultures have very long incubation and nestling periods, with nestlings requiring some 135-140 days to fledge. Fledging literally means taking the plunge; fledglings leap off the cliffs and have that one chance to gain their wings!
The diminutive Egyptian Vulture, extinct over most of its original range in southern Africa, is rarely seen in Namibia nowadays. Namibia can, however, claim the only known breeding record for this species in southern Africa in recent times – according to our local expert Chris Brown. The Egyptian Vulture is, however, still fairly common in other parts of Africa, notably Ethiopia, where they are commensal with man, foraging on rubbish and offal dumps outside villages. Known as “Pharaoh’s Chicken”, the Egyptian Vulture has gained both fame and notoriety for its distinctive “tool-using” behaviour. When confronted by Ostrich eggs, Egyptian Vultures will select a suitable stone, stand alongside the egg and throw the stone down onto the egg with considerable force. Eventually, after throwing the stone a number of times, the egg breaks, and the vulture is rewarded with the rich yolk. This behaviour was well known to the early Ostrich farmers in the Cape province of South Africa, who consequently persecuted the species in retaliation, resulting in the relatively early extirpation of the species there. Egyptian Vultures invariably build their nests on cliffs, typically situated in holes or caves or under overhanging ledges, and generally lay a clutch of two eggs. Apart from its distinctive tool-using behaviour, the species has been very poorly studied in Africa.
Other vultures which may still be seen in Namibia include the Whitebacked, Hooded and Whiteheaded Vultures.
The Whitebacked Vulture is the most common vulture of wildlife reserves and commercial farms in Africa. It is noticeably smaller than the true griffons, and typically nests in Acacia trees of open wooded savannas. Gregarious in the extreme, these vultures are vociferous, even frenetic, feeders of carrion. As many as 200 individuals have been seen at relatively small carcasses of Impala, and considerably more will congregate at larger carcasses. A flock of Whitebacked Vultures demolishing a carcass is an astonishing, wild sight, to put it in Thomas Ayres’ (1869) understated words!
Over much of Africa north of the Equator, Hooded Vultures are commonly and abundantly commensal with man, even more so than the Egyptian Vulture. However, in strong contrast, the southern African populations of Hooded Vulture are shy, wary of man and secretive of breeding habit. Although gregarious at carcasses, offal dumps and roosts, they are solitary breeders, nesting within the canopy of tall trees, often in dense riparian woodland. Like the Lappetfaced Vulture, the Hooded Vulture’s face and bare throat flush bright red when excited. Much smaller than the other vultures, it keeps well out of the melée at carcasses, preferring to pick up scraps of meat dropped by the other scavengers, and unlike Whitebacked and Cape Vultures, does not become soiled while feeding. It is often one of the first scavenging species to arrive at a carcass, and feeds hurriedly before it is forced away by the larger vultures. Once a carcass is reduced to skins and bones, Hooded Vultures pick these remains clean with their particularly thin bills.
By far the prettiest vulture in Africa, the Whiteheaded Vulture is a somewhat enigmatic species, in being the only vulture which is sexually dimorphic in plumage colour. Unlike other vultures, it is distinctly unsociable, usually seen singly or in pairs, and is nowhere common in southern Africa. Whiteheaded Vultures will come to large carcasses to feed, but remain on the fringe of feeding activities. They appear to favour small animal carcasses, and they have been seen feeding on a wide range of fish, bird and small mammal species. Accordingly, like the Lappetfaced Vulture, they have thus also gained notoriety as potential predators of small domestic livestock. Increasingly, much concern is expressed for the survival of this species, and, in Namibia, it is likely that it has died out in much of the interior as result of the use of poisons by farmers. In much of southern Africa it now confined to wildlife reserves.
Vultures are one of the most persecuted groups of animals and, regrettably, they represent but a tip of man’s destructive iceberg. However, since they are so adversely affected by the pervasive behaviour of the vast majority of commercial small stock farmers in southern Africa, they are also conspicuously symbolic of good farming practises. Harshly generalised about here, there are many farmers who do practise ecologically-sensible farming techniques, restock their land with game, and afford protection to predators and scavengers. We can only hope that in becoming more familiar with the habits of jackals, vultures and other animals, farmers will realize their value, and become more tolerant of the wildlife that share their land. Conservation, after all, is an entirely human activity.
Joris Komen lives on a farm outside Windhoek where there are no sheep.