Wingbeats over the KAZA
Wingbeats over the KAZA
Most of our vultures have a wing span of two metres and more, even up to three metres. And with body weights of between 2kg and 10kg,they are formidable birds. Vultures soaring in a thermal,and gathering in dozens, even hundreds, at a carcass in the bush,are formidable sights. This is how we know them in the savannas of Africa. There cannot be a single game ranger or tourist guidewho is not familiar with the birds,and hopefully knowledgeable about them too. Body:
The most common vulture in southern Africa is the white-backed vulture that occurs in the low thousands throughout the KAZA TFCA –the Kavango Zambezi Transfrontier Conservation Area -and indeed along the whole length of the Zambezi River. There it is, circling around in a thermal, then planing to the ground in a fast and audible glide, occasionally in a plummet, so anxious it is to get to ground level, and here it is at a carcass jumping around and feeding in a frantic fashion. It is thrilling for us as observers to see that progression, and to ponder-and admire- these features that enable an individual, and particularly an adult, to survive.
For much of each day a vulture is on the look-out for food, usually a carcass of a mammal that can be seen from the air. Other kinds of food, for examplea dead python, or catfish stranded in a shrinking pool (the so-called ‘barbel party’),or a termite emergence, or animal faeces, are recorded but seldom taken.
In fact vultures are better at spotting another bird arriving at the carcass, ie: movement, than the stationary carcass itself. And if the carcass is large enough, up to nine species of scavenging bird can be seen, being the five common species of vultures plus three species of eagle and kite, and the Marabou stork. This is a spectacle (supposing that one can identify all in the ‘rogues’ gallery’!), though such a complement is very rarely to be observed. Individuals of each species are intent on getting a meal, and at the same time each is in fierce competition with many others. The scene is simply one of survival, red in tooth (beak rather) and claw. Survival of the fittest comes immediately to mind.
If our adult white-backed vulture is successful at the carcass, it will swallow enough meat to last it for three days. Nevertheless it probably flies and soars on everyday that it can (not in rainy weather). If it so desires, it can move up to 200km per day. Within a month and perhaps less, a vulture could fly over the whole of the KAZA TFCA, in effect integrating this huge slice of African savanna under the wingbeats of one individual. But therein lies its potential doom!