Southern Africa's Threatened WildlifeNearly 900 bird species have been recorded in southern Africa and some 74 of these are endemic to the region. 10 of these endemics are threatened. Several species have extremely isolated populations in the region. The SARDB-Birds includes 102 species, but healthy populations of some 40 of these are found in Botswana, Namibia or Zimbabwe. There are, however, a number of species in these countries which are threatened. Examples are the Taita Falcon which lives in the vicinity of the Victoria Falls and at other sites in the Zambezi valley, and the Blackcheeked Lovebird which formerly occurred along the Zambezi valley in Zimbabwe and Caprivi. Amongst other factors, these two birds are at risk from trapping for falconry and the cage-bird trade respectively.
In the South African context, nearly half of the RDB bird species are dependent upon grasslands or wetlands. These habitats are therefore clearly the most in need of conservation attention at present. Scavenging birds, dependent upon carrion, are the most threatened group according to feeding habits. Seven of the eight vulture species in the region are threatened and the specialized Vulture Study Group works, and campaigns, for their survival.In general, it appears that large birds face more man-induced problems than the smaller songbirds. Cranes, bustards, vultures, eagles and storks are regularly featured in Red Data Books both here and abroad.
When the SARDB - Birds was published in 1984, the African Skimmer and Yellowbilled Oxpecker were listed as "extinct" [as breeding species] and the Egyptian Vulture as "endangered" but possibly "extinct". The skimmer occurs along the Okavango and Zambezi rivers in the very north of the region, but is threatened there and is being treated as "endangered" overall. The oxpecker is widespread in northern Botswana, Zimbabwe and north-eastern Namibia, has recently recolonised the Kruger National Park and has been re-introduced into the Umfolozi Game Reserve in Natal. Its status is therefore improving steadily but it is still included as a "vulnerable" bird in this book. The Egyptian Vulture seems to be the only species that has actually disappeared from South Africa as a breeding species, but there exists the possibility that it may be resident in north-western Namibia, so it is considered "endangered" in the sub-continent.
Space does not permit the detailed discussion of all of the regionally threatened birds in this book. Among those which have been omitted, but that are also deserving of conservation attention, are Rudd's Lark, Yellowbreasted Pipit, Spotted Thrush, Bittern, Rock Pratincole, African Broadbill, Grey Kestrel and Pinkthroated Longclaw.
A number of birds are extremely rare in southern Africa simply because the specific habitats which they require are limited. The Palmnut Vulture, with less than six known pairs, and Woodward's Barbet, which occurs only in the Ngoye Forest in Zululand, are two notable examples. Nothing can be done to improve the status of such species short of creating more habitat - a virtually impossible task. Luckily, most of these species have healthy populations in other parts of Africa.
Egyptian Vultures breed as isolated pairs on cliffs, and forage in open country. They attend carcasses along with other species of vultures, but also forage extensively around human habitations where they eat any kinds of food they can find, including animal and human faeces. This last habit has given them the uncomplimentary German name of "Schmutzgeier". They are well known for their habit of breaking Ostrich eggs, using stones as tools which they throw down with their bills to crack the shells. This did not endear them to the Ostrich farmers of South Africa at the end of the last century, who retaliated by shooting and poisoning the birds. This relentless persecution may be the reason why the Egyptian Vulture disappeared from most of South Africa, but it does not explain why the birds should also have disappeared from Transkei, where there seems [to humans] to be adequate food that supports a healthy Cape Vulture population.
One interesting theory is that Egyptian Vultures in Transkei depended heavily on small food items found around human settlements. In Transkei domestic pigs are very abundant, range freely and pick up every available scrap of food. This competition may have proved too much for the vultures and led to their final demise. Work is presently being undertaken to build up a captive flock of Egyptian Vultures in South Africa to release into the wild. Captive birds may be seen in the Johannesburg Zoo, and the Larvon Bird Gardens in Harare. All belong to the subspecies ginginianus, found in China and India, and the progeny from these birds would therefore not be used for a re-introduction programme. Most scientists agree that the same subspecies that originally occurred in an area must be re-introduced there, if at all possible.
South Africa has some 120 pairs of Wattled Cranes left, and it is probably no exaggeration to say that the original wetlands could easily have supported ten times this number, maybe even fifty times!. This is a measure of the damage done to sponges by draining, damming, burning and afforestation, and also an indication of the amount of work needed to restore South Africa's wetlands to a semblance of what they were a hundred years ago. Unless this restoration is tackled as a national priority, devastating floods will continue to rob the land of its topsoil and cause damage running to millions of rands every year.
In Zimbabwe, Wattled Cranes breed in the northern half of the country, mainly on wetlands in the east and central parts. The Okavango Delta of Botswana has long been regarded as a stronghold for the species, and in some years flocks appear on the Makgadikgadi Pans. During exceptionally wet years non-breeding flocks may visit pans at Grootfontein, Etosha and Owambo, all in Namibia. In this country Wattled Cranes breed in the Mahango Game Reserve in Kavango, and on Lupala and Nkasa Island in eastern Caprivi. These cranes are reportedly numerous in the wetlands at the delta of the Zambezi River in Mocambique, but information is needed on their current status there. There is no doubt that the Wattled Crane is a very special bird throughout southern Africa, and deserves ongoing research and monitoring. It is a "flagship" species for wetland conservation.
The small South African population now seems to have stabilized, and some important breeding areas have been purchased by the provincial conservation authorities in Transvaal and Natal. The potential of artificially hatching and rearing chicks from two-egg clutches is very good. Wattled Cranes never rear more than one chick from these two-egg clutches.
There are several reasons for the decline of the Roseate Tern, most of which are basically "human disturbance". As recently as 1960 eggs were illegally collected for human consumption. When people disturb the breeding terns just by walking among the breeding colonies, this gives Kelp Gulls the opportunity to go in and snatch eggs and chicks. Strict protection of Roseate Terns in secure and controlled breeding reserves is the most effective measure that can be implemented. Some control of Kelp Gull numbers at Roseate Tern breeding islands would also help, while the provision of secure artificial nesting sites has been successfully tried in North America. Finally, domestic rabbits were introduced to Bird Island in Algoa Bay, where they interfere with the breeding Roseate Terns. The rabbits are an unwelcome exotic species, and should be removed in the interests of the indigenous terns. Wise management could certainly improve the prospects of this rarest breeding seabird.
African Skimmers still breed in numbers along the Okavango and Zambezi rivers, and their vulnerability to human disturbance has recently been highlighted. Eggs and chicks are collected by people for food, or to use as bait for fishing. The use of boats with outboard engines has enabled people to reach areas which previously were too remote for casual visits. On the Okavango River, some thoughtless boat drivers travel too fast, setting up a bow wave that is sufficient to flood the low sandbars where the skimmers nest in small scattered colonies. This results in eggs and small chicks being drowned. Eggs or nestlings are also trampled by people venturing onto sandbars. An active awareness programme is needed in areas where people are likely to drive boats past breeding African Skimmers.
Blue Swallows breed in natural and artificial holes in the ground on the mountain plateaux of eastern Africa south of the equator. They extend from Natal to Tanzania in a series of isolated populations. All are migratory, moving to the Lake Victoria basin in central Africa to overwinter. Blue Swallows live in rolling montane grassland, without extensive rocky outcrops or steep slopes, in areas of mist, high rainfall and deep soils. It is their dependence on these specialized requirements that has proved disastrous for their survival in South Africa, because these are precisely the conditions that make land suitable for commercial forestry !
Forestry is a huge and efficient industry in South Africa, earning the country large amounts of foreign exchange through wood and paper exports. Foresters have methodically identified each and every area in Swaziland and Transvaal that meets the requirements for successful timber production, and most of these have now been covered in an unbroken blanket of pine and gum trees. Only fragments of the remaining grasslands remain, and some of these support the relics of a once widespread population of Blue Swallows.
In parts of Natal sugarcane fields have covered grasslands, and large areas of grassland have recently been bought by the large timber companies for afforestation. Sprawling human settlements in parts of Natal and Zululand have engulfed more Blue Swallow habitat. A survey conducted by the Endangered Wildlife Trust over the 1985/6 and 1986/87 breeding seasons revealed only 63 pairs of Blue Swallows in all of Natal, Swaziland and Transvaal.
Of these breeding pairs, only 10 could be considered as secure, and at least 44 were threatened, with 20 likely to disappear within 12 months ! Intensive efforts were made to secure further breeding sites, and fortunately a number of these were on State land. The Department of Environment Affairs rose to the challenge, as did the Transvaal Directorate of Nature Conservation and the Natal Parks Board, and the number of Blue Swallow pairs that were secure quickly increased from 10 to 37. This bird, the most endangered in South Africa, now has a chance, albeit slim, of surviving into the 21st century.
The status of the bird in Mozambique is unknown, and it is not doing as well as it could in the montane grassland of eastern Zimbabwe. This is largely due to the proliferation of invasive exotic plants such as pines and wattle, which are covering the original grasslands and smothering the breeding holes of the Blue Swallows.
There are three different subspecies of the Blackrumped Buttonquail in Africa, one of which is widespread throughout tropical regions. The subspecies originally described from the southern Cape has decreased drastically. The status of the other subspecies found from the eastern Cape to the Transvaal and Mozambique is virtually unknown.
In general it seems that the loss of grassland throughout southern Africa by overstocking, trampling by livestock and burning has resulted in the Blackrumped Buttonquail being on the Endangered list. Several other species are now Vulnerable for the same reason. Without a better idea of the present distribution and habitat requirements of the Blackrumped Buttonquail, it is difficult to provide an adequate management plan to prevent its extinction. Here is a good project for a keen young ornithologist!
The early European settlers at the Cape of Good Hope soon realised that penguin eggs made good eating, and over the years countless millions were collected. What made matters worse was the practice of destroying any incubated eggs so that there would be fresh ones when the egg collectors next visited ! Then the valuable guano on the breeding islands became the basis of a new industry, and thousands of tons were removed by labourers. This not only had the effect of disturbing the birds, but because the islands were scraped down to the bare rock, the penguins could not dig their nesting burrows into the guano, and so eggs and small chicks became more vulnerable to predation by Kelp Gulls.
In the 1950s and 1960s, overfishing of pilchards reduced the food supply for breeding Jackass Penguins, resulting in lower breeding success. The population of Cape Fur Seals has also increased in southern African waters, and the seals interfere with the nesting of the penguins. To make matters even worse, Jackass Penguins are vulnerable to oil spills from the numerous tankers passing around the tip of Africa, and many were killed by underwater blasting during the construction of the ore-loading facility at Saldanha Bay.
Many measures have been proposed to aid the Jackass Penguins. These include not fishing within 10 km of breeding colonies, not scraping guano from penguin breeding islands, building walls to keep seals out of penguin breeding colonies, and strict access control to islands on which penguins breed. An interesting development in recent years has been the breeding of Jackass Penguins on the mainland at Betty's Bay. This seems to be the direct result of the erection of a predator-proof fence erected to protect breeding seabirds. Good results have also been achieved in treating oiled penguins - ringed birds have been found breeding successfully after being cleaned and released. Jackass Penguins have recently reestablished their Robben Island breeding site (abandoned before 1800) and each year their numbers increase. This is largely due to the enthusiastic protection afforded by the Prisons Department on this notorious island.
The decrease of the Cape Vulture is indirectly due to the replacement of the wild antelope populations of southern Africa with livestock. In areas where sheep are farmed, an unrelenting war has been waged against real and imagined predators for the past 100 years and more. Poison has been extensively used, primarily to kill the Blackbacked Jackal.
This has had a disastrous effect on scavenging birds. The distribution of a suite of scavenging vultures and eagles shows them common in the Kalahari Gemsbok National Park [South Africa and Botswana] and the Etosha National Park [Namibia], but absent from the farmlands in the vast area between these sanctuaries. Because they gather in large numbers at a carcass, vultures are especially susceptible to poisoning. In two incidents in Caprivi, Namibia, 100 and 150 vultures were killed by insecticide placed on the carcasses of an Impala and an elephant.
The Cape Vulture is also vulnerable to shooting and disturbance at breeding colonies, and to electrocution on certain types of electricity towers. Perches fitted to the lethal towers by Eskom to protect vultures from electrocution made the electricity supply more reliable at the same time.
Hyaenas used to crush the bones of carcasses into slivers which the adult vultures would collect and feed to their chicks as a source of dietary calcium. Hyaenas have been eliminated from farms, and without this supply of bone fragments, young Cape Vultures developed symptoms of a calcium deficiency, having weak and deformed bones.
Various feeding sites or "Vulture Restaurants" have been established to supply the birds with poison-free meat and bone fragments. There is today much more awareness about the plight of the Cape Vulture among landowners, but until there is a real conservation ethic practiced by every farmer where Cape Vultures occur, the birds will remain vulnerable to poison.
Lappetfaced Vultures occur throughout southern Africa, but are not found south of the Orange River or in the montane and highveld grassveld areas. They are found in a wide variety of habitats but appear to prefer more arid regions. They are seldom encountered outside protected areas in South Africa and Namibia any more, an indication that the irresponsible use of poisons on farmland is the major threat to this species. In Botswana, where poisons are rarely used by farmers, the species is not threatened in any way.
Adult Lappetfaced Vultures often do not obtain as much meat as other vulture species at carcasses. Since they also bring many small animals to their nestlings, the interesting possibility exists that they may be capable of killing their own prey. Documented observations of this from the field would be of great value.
A pair of Martial Eagles will defend a large territory around their nest. This may be 100 square kilometres or more, so birds with nests inside protected areas may have territories extending into adjacent farmlands where they are vulnerable to being killed by unsympathetic landowners.
Another threat to the Martial Eagle is electrocution on rural powerlines. In contrast to this is the increasing tendency for Martial Eagles to build their nests on high voltage electricity transmission towers. This has come about because of a new sympathetic attitude by Eskom personnel towards birds nesting on towers. It used to be common practice to remove all nests during maintenance work, but now this is only done if there is a real danger that the electricity supply may be interrupted.
These eagles are very sensitive to human disturbance, and will abandon their nests if there are too many people around. The clearing of large areas of woodland and savanna for agriculture has caused a great loss of habitat as well. It has been estimated that there were possibly 2 500 breeding pairs of Bateleurs in the Transvaal 100 years ago - now there are less than 600. To add to the problems faced by this species, the immature eagles are a drab brown colour, resembling other "hawks" which some landowners, especially poultry farmers, shoot on sight.
The Kori Bustard is the heaviest flying bird south of the Sahara, and may reach a mass of 19 kg. It has declined over much of South Africa in the face of intensive agriculture, hunting and possibly poisoning with strychnine baits aimed at small stock predators. It is also considered to be a vulnerable species in Zimbabwe. Botswana and Namibia are the major strongholds of the Kori Bustard in southern Africa.
Stanley's Bustard occurs in grasslands and coastal fynbos in the east and extreme south of South Africa, some of the most densely settled areas in the country. The grassland habitat is disappearing under agriculture and commercial afforestation. In the southern Cape the bustard seems to have adapted to living in planted pastures in the fynbos, despite the heavy human disturbance.
Ludwig's Bustard occupies the open plains of the Karoo and associated desert areas in the west, and its status appears to be healthy and not really "vulnerable" at present. However, there is concern about a recent finding that Ludwig's Bustard seems to be very susceptible to collision with overhead wires during its long-range seasonal movements.
The eastern Cape parrots will travel long distances of up to 80km each way from their breeding sites in the inland forests to feeding places in the coastal forests. This highlights the difficulty of conserving the Cape Parrot successfully, because although many of the inland forests belong to the State and can be adequately managed for the benefit of the birds, many of the coastal forests, and of course agricultural areas, are difficult to protect.
The Cape Parrot is faced with several threats. Firstly, large forest trees in which the parrots breed in holes are often selectively cut because their wood is valuable, or because they are dead. This results in a shortage of nesting sites, not to mention destruction of eggs or chicks that might be in the trees when they are felled. Next, it appears that many Cape Parrots are illegally trapped for the cage bird market, which has been so destructive of parrot populations all around the world. Finally, they may be shot by farmers when causing damage to crops, the most important being pecan nuts which are being increasingly cultivated in the foraging ranges of the birds living in the eastern Cape.
Ground Hornbills have lost suitable habitat due to agriculture and changed land-use. They sometimes smash window panes while attacking their own reflections, a habit which results in irate householders shooting the birds. And like so many of our other threatened birds, they are vulnerable to picking up poison baits set out for predators. Any unnatural mortality of these slow-breeding hornbills is likely to have a serious effect on their populations.
From about 1875, with the introduction of the breech-loading rifle for hunting in South Africa, and the slaughter of game which this precipitated, the numbers of buffalo and rhinoceros, on which Yellowbilled Oxpeckers prefer to forage, decreased rapidly. Their place was taken by cattle, on which the oxpeckers could forage and maintain their numbers even though their favoured wild hosts were gone. Then the Rinderpest epidemic of 1896 vastly diminished the cattle herds, and just as they were recovering again, arsenic dips to control ticks were introduced. The dipping of cattle was required by the Colonial Governments, and by 1910 the Yellowbilled Oxpecker was extinct as a breeding species in South Africa.
In the early 1980s a number of scientists suggested that the Yellowbilled Oxpecker could be successfully introduced into the Kruger National Park and the Hluhluwe-Umfolozi Complex in Natal. Populations of buffalo and rhinoceros in both areas had built up under the protection of the National Parks Board and the Natal Parks Board. By the beginning of 1986 plans were well advanced to capture a flock of Yellowbilled Oxpeckers in East Caprivi for re-introduction to the Kruger National Park.
Then positive evidence was produced that the species was recolonizing the Kruger National Park from the north ! The effects of the civil conflicts in both Zimbabwe and Mozambique had apparently contributed to a breakdown of cattle dipping programmes, and the birds increased on domestic livestock, then reached the buffalo and rhino populations to the south and west of these countries. Yellowbilled Oxpeckers are still expanding their range southwards in the Kruger National Park.
The destination of the Caprivi oxpeckers was then switched to the Umfolozi Game Reserve. The captured birds were flown in a light aircraft by Derek Ritchie, Trustee of the Endangered Wildlife Trust, who described their release:
"We stood around for a while savouring the moment - the Yellowbilled Oxpecker was back in Natal after an absence of 80 odd years, and we had captured and transported 43 birds in a short period and over a considerable distance without a single loss."
Evidence of breeding in Umfolozi was later confirmed. Dips that control ticks, but are safe for oxpeckers, are available and it is to be hoped that all livestock owners in potential oxpecker country will use these products, so that the birds will come to live on their farms, and help control the ticks on their domestic animals.
Redbilled Oxpeckers have been successfully re-introduced to places like Loskop Dam and the Ben Lavin Game Reserve in the Transvaal. These re-introductions have focussed the attention of landowners on a keystone species in their environment, and have done much to heighten awareness about the delicate inter- relationships between the components of ecosystems.
