The vulture is a scavenging bird of prey and an animal that is often being portrayed as evil and motley. Don’t get me wrong as these birds are by no means what come to mind when we speak of warm and fuzzy.
But if you dig into their purpose a bit, you may ask yourself, are they really as bad as they are made out to be, or are they just perfectly designed to fit a less glamorous yet important role in our natural areas?
There are 23 recorded species of vulture that soar above our beautiful planet today. Southern Africa is home to nine of these species, all of which are large powerful birds with massive wingspans that spend most of the day aloft in search of carrion to eat. These birds are equip with a large hooked shape bills designed for tearing through the flesh, tendons and skin of big mammal species. Almost all species are carnivorous except for the aberrant Palm Nut vulture that is known for its vegetarian intake.
Here is a list of some of the more common Southern African species and their conservation status:
- White-Backed Vulture – Critically Endangered
- Cape Vulture – Endangered
- Egyptian Vulture – Endangered
- Hooded Vulture – Critically Endangered
- Lappet-Faced Vulture – Endangered
- White-Headed Vulture – Critically Endangered
Getting back to their gruesome ways, the general feeding behavior of vultures around a carcass is something that may resemble an end-of-year sale at a department store. It starts with a mad scramble for the doors, followed by shoving and jostling at the bargain counters and ends with the most robust and pushy customers staggering off with their spoils, leaving the depleted pickings for the latecomers. It is surely a sight to behold, the combination of the smell and noise, with bloody birds emerging with full crops from the carcass is a spectacle of note.
Before we dig deeper into their feeding habits, lets learn more about how they find their food first.
Understanding a vulture’s senses
Vultures like all birds depend on their senses for survival, their senses have adapted to give them the best chance to thrive and survive.
Birds have the same senses we do, sight, hearing, taste, touch and smell. Theirs are of course more specialized and developed to help them survive and the importance of certain senses varies from species to species. Vultures have a particularly well developed sense of sight.
A vulture’s eyesight is critical to it finding food, evading predators and avoiding hazards like power lines while flying. Vultures have a thicker retina than humans and their eyes are larger in proportion to their head size. They also have a higher density of cones and rods packed into the retina, giving them far superior vision to us. It’s believed that these birds can see a carcass as small as a warthog in the plains from kilometers away. They see movement and detail much better than we do, and their eyes are set further apart on their head’s giving them a wilder field of view. Because their eyes are so important, they have a necessitating membrane (an inner eyelid) that helps to protect their eyes and cleans them often.
Their ears are located slightly behind and below the eyes, and are covered with soft feathers; called auricular, for protection.
Vultures may not sing, but they hold a conversation all of their own. Using noises like hissing, grumbling and squawking at each other they hold some very funny conversations at our vulture restaurant.
Touch or feel, is vital for their flight. They are incredibly sensitive to changes in air temperature, pressure and wind speed. The sensations are transmitted down the feathers to the nerves in the skin. They have fewer nerves in their legs and feet, this allows them to perch or stand on hotter or colder surfaces.
Now why is air temperature, pressure and wind speed important to them you might be wondering.
As these birds do not get to eat daily, they are massive energy savers. Vultures use rising thermals to facilitate low-energy flight. Pockets of rising warm air form when the sun heats the ground during the day and these thermals provide lift to the enormous birds. Vultures are equipped with enormous wingspans of up to 2.8 m, in Lappet-faced vultures, which suit this style of flight. Using thermals prevents the necessity to flap these large wings and thereby the birds save more than three times the energy that would be needed in flapping flight.
Vultures use thermals to gain a height vantage to look for food and by moving from one thermal to the next they can survey vast areas while foraging. It is crazy to think that vultures can soar at altitudes up to 12000 m, covering thousands of kilometers at a gliding speed of about 60 kmph but up to 80 kmph. Vultures are restricted to flying only during the sunny hours of the day and generally find themselves grounded at night and on overcast days.
Now once they come across a, not so delicious meal, fortunately birds do have a sense of taste, but it is not well refined. Depending on the species they have less than 50 or up to about 500 taste buds (Humans have 9000 – 10 000 taste buds).
Birds in general don’t have a wonderful sense of smell; some Vultures however have a better developed sense of smell than others but sight is still the most important of the five senses.
Now with that insight, lets get back into their feeding behavior. There is usually a general pecking order amongst vulture species at these feeding frenzies, mostly dictated by numbers and size. Vultures, although known for their spectacular eye sight, are often led to carcasses by Bateleurs, these birds have a remarkable ability to spot carrion, and their low-circling decent is a signal to an armada of scavenging species that there is something of interest down there.
Next arrivals are usually the smaller White-headed and Hooded vultures who wearily watch the carcass alongside the Bateleur, before the bravest of them start to drop down and approach the carcass. These smaller vultures usually don’t have a lot of time before the real carcass hogs arrive, the White Backed Vultures who are also one of the most common in the region.
These vultures all dropping in on the carcass in large numbers with their pig-like squeals and flapping wings all jostling and fighting for space make quick work of the carcass with the White-headed and Hooded Vultures being swept aside by the chaotic behavior of the white backs. Almost too late usually, the Lappet-faced Vultures (the largest of our species) plane in and land with a bounce on the ground. With wings spread open they advance forward, clearing their path with their sheer size and demeanor, often getting side tracked in quarreling with other vultures. They usually take what’s leftover such as skin and bones and tougher pieces of meat that their big strong bills allow them to deal with better than other vulture species in anyway.
So believe it or not, there is order amongst the chaos after all. Working together like they do, it may take only a few minutes for an average sized carcass of about 50 kg to be reduced to just bones. All the noise usually will attract the attention of nearby scavengers of the larger variety such as Hyenas or even Lion. So if you do come across some vultures feeding on your next safari, it may be worth your while sticking around to see what else may appear.
So by taking on the role as the so called ‘garbage ‘removers of the bush, these birds play an incredibly important role in removing centres of disease and bacteria such as anthrax and botulism, that may spread from these sights.
Unfortunately vulture populations are facing a continual and rapid decline in their numbers over the southern African region owed to many different threats. These birds fall victim to contaminated food supplies from certain drugs used to treat livestock, this being poisonous to vultures. They inadvertently ingest pest control poisons intended for other animals and electrocution from collisions with power-lines are critical issues that lead to the deaths of many vulture species.
Vultures also face a huge threat from the harvesting of body parts for traditional medicines in southern Africa. It is believed that they contain the powers of premonition or foresight and those ceremonies using the birds’ brains can transfer these powers to a person.
Possessing a foot of vulture is also believed to bring good luck. With more than 60 percent of the South African population still consulting traditional healers, the use of protected species’ body parts will be a persisting problem to address in the future.
These grossly underrated birds are heading towards local extinction in many regions if these serious threats are not addressed soon. Trust me, you do not even what to work the knock on effect that will be in play if we start losing our vultures. The outcome is very daunting to say the least.
Studies show that a disappearance of these birds may lead to severe ecosystem imbalances. Raising the profile and public perception of these birds may lead to increased conservation efforts for them as it has done so for many previously underrated animals such as the African Wild Dog in recent years.
Please support conservation efforts for the many threatened and endangered vulture species in southern Africa today, educate your friends and family on the importance of species instead of stigmatizing them as this may all have an impact on how they are perceived by the greater public in future.
Education = Conservation
I do hope that this blog has educated you somewhat on these feathered creatures important role in the ecosystem as well as changed your perspective on vultures.
Please feel free to leave me any questions in the comments below.