The Kruger National Park covers an area of 19,485km2 and consists of 8 distinctive vegetation zones. These, in return, ensure species diversity as can be found in few other parks. With predators like lions (Panthera leo), leopards (Panthera pardus), spotted hyenas (Crocuta crocuta), cheetah (Acinonyx jubatus), wild dogs (Lycaon pictus) and even smaller predators like jackal being abundant, there is always going to be enough food around for scavengers.
Vultures can be found in good numbers throughout the park and six of the nine species found in the sub-region can be seen while on a Kruger Park safari.
The heaviest of the vultures one can see in the park would be the Cape Vulture (Gyps coprotheres), or Cape Griffon as it is sometimes referred to, with some birds weighing as much as 9.5kg. In size they are very similar to the Lappet-faced Vulture (Torgos tracheliotos) but the latter does have a larger wingspan and may be a cm or two larger in size, which would make it the largest of the vulture species found in the sub-region.
Cape Vultures roost and nest on the cliffs of the Drakensberg mountains and typically fly into the park in search of an easy meal. They are by no means a common vulture in the park, but some time spent out on game drives and, in particular, at carcasses may produce at least one sighting of these large aerial scavengers.
Superficially they look a lot like the smaller White-backed Vulture (Gyps africanus), but lack the obvious white back. They are paler in colour, have a pale eye and a blue/grey neck. Some experience with vultures may be required to distinguish between the immature birds, with size here being the main distinguishing feature.
In flight and from below, the Cape Vulture adults are paler with dark-tipped secondaries. White-backed Vultures have both secondaries and primaries are a uniform dark brown. The size of White-backed Vultures allows them to dominate at carcasses and ensures they get the best spoils. Only the Lappet-faced Vulture is able to present some competition.
At an average of 102cm in body size and a wingspan of almost three meters, Lappet-faced Vultures are regarded as the largest vultures in the sub-region, and are easy to pick out, whether down on the ground at a carcass or circling high in the sky.
As the name suggests, these birds can be identified by their loose, folded, pink facial skin or ‘lappets’. They are dark brown in colour with contrasting white, down-like feathers on the belly and thighs. A large, heavy, horn coloured bill aids this species in ripping through tough skin that most other vultures would not be able to break through.
As with the Cape Vulture, Lappet-faced Vultures command respect at carcasses with smaller species being sure to stay alert and keep an appropriate distance. The Lappet-faced Vulture is also one of the ‘Big 6’ birds to try and find while on a Kruger wildlife safari, indicating its significance and popularity especially amongst avid birders.
The most common vulture species, not only in Kruger Park, but in the sub-region as well, would be the White-backed Vulture. It's usually the first species one is likely to see on a Kruger safari and whether it’s birds circling above or at a carcass, they are sure to do their best to dominate in sheer numbers. Their presence in numbers often keeps smaller, tenacious scavengers like the black-backed Jackal (Canis mesomelas) at bay. This species may become so focussed on getting a meal at a carcass that, at times, they may even be preyed on by other scavengers, like lions, and may get trapped inside carcasses and then eaten by conspecifics. Although largely a scavenger, White-backed Vultures have rarely been recorded preying on springbok lambs and warthog (Phacochoerus aethiopicus) piglets. At feeding frenzies, it may fill its crop with up to 1kg within 2 to 5 minutes.
At a mere 2kg in weight, the Hooded Vulture (Necrosyrtes monachus) is one of the smallest vultures with only the Egyptian Vulture (Neophron percnopterus) being slightly smaller. This species is abundant in Kruger Park and is often seen circling on thermals with White-backed Vultures, or it may sit around on the periphery at carcasses waiting for a safe and more opportune moment to feed.
Their smaller size and, in particular, their slender long bill does aid them in getting into smaller spaces to easily feed on flesh around eye-sockets and in-between the ribs. They are often the first and last vulture species at a carcass and it is believed that other vulture species keep a close eye on Hooded Vultures as an indicator for when a carcass has been found.
The White-headed Vulture (Trigonoceps occipitalis) is probably the most striking vulture species found within Kruger Park. It is less common than the species mentioned above and, therefore, a sighting of one of these is always extra special. An adult bird has a white, woolly crown with a pink face, (which when excited flushes red). The base of its bill is a light blue and the tip of the bill can be orange to bright red giving it a lipstick appearance.
The upper parts are mostly dark brown to black, while in flight, and from underneath the white greater covert contrasts with the black leading edge to form a diagnostic bar. White-headed Vultures not only scavenge, but also resort to kleptoparasitism with eagles, and will kill small mammals when given the chance. Some of its prey include hyraxes, the bat-eared fox (Otocyon megalotis), scrub hare (Lepus saxatilis), various snakes as well as tortoises and even giant bullfrogs (Pyxicephalus adspersus).
The last of the vulture species to be discussed is the Egyptian Vulture (Neophron percnopterus), also sometimes referred to as Pharaohs Chicken. This species can reliably be found across parts of North Africa, Southern Europe and the Middle East.
It typically doesn’t wonder further south than Angola, but occasional roaming birds can be found venturing into Kruger Park. It’s not a species you can specifically go on a Kruger Park safari to see, unless of course, news is out than one is drifting through the park.
Usually these are immature birds and, with Egyptian Vultures, the younger birds can superficially resemble the Hooded Vulture, which is similar in size. The main feature to be on the lookout for is the wedge-shaped tail (in flight), and the bare facial skin with long neck feathers. As the birds mature, they turn white, the facial skin becomes a bright yellow – flushing orange when excited - and they then are unmistakable.
Egyptian Vultures prefer open country and areas that are arid. They are perhaps most well-known for their intelligent way of using stones to break open large bird eggs and, in particular, ostrich eggs.
Vultures move around according to where food is available. At times, vultures may stay within eyesight of a pride of lions. This way, they are at least assured of some scraps every few days. It is also believed that vultures are able to see each other at a distance of plus minus 7km. They do not need to move in groups but can spread out giving them a better chance of covering a larger area in search of food.
Their brilliant eyesight also aids them in seeing when other vultures drop to the ground and, hence the reason, when there is a carcass that birds seem to appear out of nowhere. There is a myth that vultures follow dying animals. Mostly, when vultures are seen circling, they are merely all making use of heat thermals to gain altitude.
Vultures are heavy birds and a lot of flapping would result in too much energy being lost. They are therefore dependant on using these heat thermals and then cross winds to soar and glide on, and can then easily cover vast distances. However, if you see a lot of vultures soaring above and some dropping to the ground then it is likely they have located a kill or carcass.
In areas like and along routes near Satara, where the vegetation is open and dominated by Marula (Sclerocarya birrea) and Leadwood (Combretum imberbe) trees, vultures may often be seen perched on these trees and dead Leadwood trees are also a perfect roost site or vantage point that vultures are able to use when they are near a carcass, yet need to stay out of the way of apex predators like lions.
Vultures have a number of interesting adaptations. Some of them have eyes that are set deep in powerful eye-sockets. They also have a series of cardiovascular adaptations. This allows them to fly at altitudes very few other species can reach and cope with not only the air pressure, but thin air and limited oxygen levels as well.
Their stomachs contain acids that are able to easily break down bones and allow them to eat rotting meat which most other species would not touch. Unlike most birds of prey, vultures do not have strong grasping talons and are unable to carry prey away.
Vultures are protected but some are endangered, meaning that it’s critical that they are protected. After all, they are vital to a healthy ecosystem. They provide a free garbage collection service by disposing of carcasses that would otherwise spread disease. Without them, disease carrying vermin populations like rats, stray domestic dogs and insect numbers would increase.
The current rate at which vultures die is unsustainable. They cannot breed quick enough to replace themselves. They are long-lived, slow breeders, taking several years to reach maturity. They fledge only a single offspring every 1 - 2 years and have a low fledgling survival rate.
It is estimated that vulture numbers will decline between 70 – 97% over the next half a century. Vulture study groups have provided 11 reasons as to why numbers are declining so fast:
This can be attributed to the use of agricultural pesticides and other poisons in carcasses, herdsman poisoning carcasses to kill other predators but then accidentally poisoning the vultures, and the use of non-steroidal, anti-inflammatory drugs in livestock that are poisonous to vultures.
Poachers actually poison carcasses to kill the vultures that will give away their position. Between July 2011 and 2014, at least ten poisoning-related incidents were discovered which resulted in the deaths of over 1,500 vultures across six southern African countries. Farmers and herdsman also falsely believe that vultures kill their livestock and intentionally poison carcasses to kill vultures.
Traditional healers believe the brains of vultures will allow them the ability to see into the future.
Collision with high tension powerlines and the resulting electrocution also play a role in the decline of this species.
Urban sprawl and increased agricultural activity to supply a growing human population has resulted in a rapid loss of habitat.
The destruction of suitable nesting trees for firewood and loss of other nesting sites due to cultivation or habitat destruction is also a contributing factor.
This can be due to drilling for geothermal wells around nesting sites, motorised transport and cultivation.
Chicks and eggs are sometimes stolen from nests for belief-based use and food.
Wind turbines built close to nesting and roosting sites or flight paths pose a high risk to vultures.
Vultures use farm dams to drink water and bathe. They fall in and drown because there is no way for them to get out.
The sad truth is some vulture populations are shrinking by as much as 50% per decade, which is why we need to do our best to conserve and protect these remarkable birds as well as enjoy and appreciate them while on our Kruger Park safaris, while we still can.