Sunday 31 October 2010

Old World Vultures

There are two kinds of vulture in the world, those of the Old World and those of the New. They are all scavengers, fulfilling the extremely important role of getting rid of carrion and clearing the place of dangerous putrefying corpses and incumbent disease. Old World and New World vultures aren't actually closely related to each other, similarities between them are purely due to their lifestyle choices.

Vultures have no feathers on their head so they don't get a load of clotting blood stuck to their noggin as they plunge their beak into rotting innards. They have extremely powerful stomach acids which not only digest their meat and destroy potentially lethal toxins and bacteria, but also have a couple other uses. When threatened, they can projectile vomit the stuff, which should get pretty much anything running. Secondly, they urinate all over their own legs. Not (just) because they are vultures and need care not a jot for what "society" thinks, but because their urine retains some of the gastric potency, allowing vultures to wade knee deep in decomposing horror without their legs turning into decomposing horrors. It also helps to cool them down, which seems like a pretty pathetic excuse if you ask me.

They are large birds, and can't go around flapping their huge wings all the time. Instead, they use rising warm air called thermals to gain height, soaring round and round and up and up in a circle like a really slow, relaxing tornado. Sometimes they're weighed down by the food they eat, though you mightn't notice. Vultures don't have the grasping feet of eagles with which to carry off their meals. Instead, they just eat as much as they can whenever they can. Chicks therefore have to be fed by regurgitation, but I don't like to dwell on that.

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The various Old World vultures are found throughout Africa, Asia and parts of Europe, but not Oceania. They can be seen flying high in the air, providing an impressive sight to onlookers at ground level and allowing them to use their keen eyesight to spot food. As you will see, people have long understood the great importance of the much maligned vulture.

The Old World family is dominated by a single genus, Gyps. Fully half of all the Old World species are part of this genus, so we may as well start there.

Image: Luc Viatour
Griffon Vulture
With its cruel eye, bald head and hunch backed appearance, this is one of the more quintessential of vultures. It reaches around 1 metre in length with a 2.5 metre wing span and weighs up to 13 kg (29 lbs), or it can weigh less than half that. It breeds in craggy mountains in southern Europe, North Africa and around Asia, laying just one egg. They can now be found in all sorts of countries across Europe due to various reintroduction schemes, where they probably died out when increasing numbers of people decided corpses were bad things to leave lying around.

In Buddhist Tibet on the other hand, human corpses were often left for vultures in a ritual called sky burial. It's a practise thousands of years old, carried out by people who believed in rebirth and saw no value in human remains. Zoroastrians in ancient Persia did the same, seeing burial as an injury to the earth.

Image: Goran Ekstrom
Indian White Rumped Vulture
Once common throughout India, Pakistan and south-east Asia, this vulture experienced a remarkable crash in numbers from the 90s on. These days, just one is observed for every 1000 that were seen in 1992. It is believed to be caused by poisoning from a veterinary drug called diclofenac, used to treat cattle and lethal to birds even in small doses. It is said that a pack of these birds could clear up a whole bullock in 20 minutes. These days that bullock may well be left to fester, causing anthrax and rabies in other less specialised animals. Some, like rats and feral dogs, can spread such diseases to humans.

Image: Lip Kee Yap
Rüppell's Vulture
About the same size as the griffon vulture above with a weight between 7 and 9 kg (15 to 20 lbs). I don't know how high up you would expect such a bird to fly, but it flies very high indeed. Their usual altitude is 6,000 metres or 20,000 feet, but one got eaten by an airplane 11,000 metres (36,100 ft) above sea level. This is the confirmed record, the highest flying bird ever known and proven. Their blood has extra high oxygen affinity to allow this, and they have extraordinary eyesight to make it useful. (Aircraft aside.) They love to fly and they love each other, gathering in huge flocks and flying at speeds up to 22 miles per hour (35 kmph). They also fly up to 90 miles (150 km) from their nests in search of food throughout the more arid and mountainous areas of Africa.

Image: Ravi Vaidyanathan
Indian Vulture
Much like its white rumped co-patriot, the Indian vulture has experienced a population decline of some 97 to 99% since the 90s. It is about the same size as the Griffon with a slightly shorter wingspan, but it is much slimmer, weighing in at around 6 kilograms or 13 pounds. It is found south of the Ganges river and breeds on cliffs.

There is an ancient Hindu epic known as the Ramayana in which there are two demi-gods who are in vulture form. They get into various scrapes, including one similar to Icarus; one demi-god flies too close to the sun so his brother courageously spreads his wings to protect him, sacrificing his own wings in the process. A vulture did that! Have you ever equated vultures with courageous self-sacrifice before? I know I haven't!


Slender Billed Vulture
This and the Indian vulture were once considered a single species called the long-billed vulture. Just recently, the slender-billed vulture has been recognised as its own species. As you might imagine, it's very similar to the Indian vulture but is found in the sub-Himalayan regions and south-east Asia, it also nests in trees rather than cliffs. Unfortunately, it too is suffering a terrible decline in numbers and is reckoned to be heading for extinction in the wild within the next decade.

Image: Jan Reurink
Himalayan Vulture
Just over a metre long, a wingspan approaching 3 metres and weighing up to 12 kilograms or 26 pounds, this is the second biggest vulture in the Old World. It nests in mountain crags in the Himalayas and Tibet, laying a single egg. They can even form loose colonies and move in flocks.

Image: John Haslam
White Backed Vulture
With its cruel eye, bald head and hunch backed appearance, this is one of the more quintessential of vultures. Yeh, again. This one is found in and above savannah in west and east Africa, where they lay a single egg in a tree.


Cape Vulture
A touch smaller than the Himalayan vulture, the cape vulture is found in southern Africa and is the largest raptor on that continent. There is another vulture in the neaighbourhood that beats it in pure power though, and we'll get to him soon.
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We have finally escaped the dread talons of the Gyps and all those griffons, only to come face to face with 8 more Old World corpse munchers. At least there's a little more variety and a little less quintessence this time. Some of these guys even look quite attractive! Or pretty or whatever.

Image: Julius Rückert
Cinereous Vulture
This skull faced fellow can be regarded as the biggest bird of prey in the world. There is a New World vulture that is slightly bigger, but not everyone even considers those to be birds of prey, that's how distantly related they are! In turn, the cinereous vulture is only slightly bigger than the Himalayan one. It can reach 120 cm (47 inches) in length with a wingspan up to 310 cm (119 inches) and a weight as high as 14 kg or 31 pounds. This makes it among the heaviest of all flying birds. It also has a more powerful beak than most vultures so it can laud it over other species and be the first to tear open the skin of carrion. It can be found across Europe and Asia, from Spain to Korea, nesting in mountains and forests.

I remember seeing a stuffed one at the Natural History Museum in London which appeared to have mascara, pink eye shadow and feathers that looked rather like breasts. It looked like a barmaid or something and I was wondering what 'cinereous' meant. Turns out it means 'ash coloured' and either the taxidermy guy was having a joke or I'm in dreadful need of a significant other.

Image: Richard Bartz
Bearded Vulture
A bit different this one, I find if you peer closely at its face and bright, eager eyes it looks sort of mythical or dragon-like. It's another big one, right up there with the cinereous and Himalayan. It's also up there high in the mountains of southern Europe, Africa, India and Tibet. You may have noticed quite a few feathers on the head, and the so called beard is a bunch of feathers, too. The thing with this vulture is it doesn't tend to eat the meat from carcasses, it prefers bone marrow. Without powerful hyena type teeth it eats bone marrow by simply eating bones. In fact, they can swallow bones as big as a lamb's femur, while larger one's are taken up into the air and dropped onto large stones to smash them into bite-sized swallow-whole bits. It's raining bones! Ow! Youngsters can take up to 7 years to learn how to do this rather morbid trick. Luckily the powerful guts required to dissolve massive chunks of bone are more inherent.

Image: Schristia
Palm Nut Vulture
A rather attractive creature this one, found in forests and savannah in sub-Saharan Africa, the same place as the oil palm. It usually breeds near water and looks unlike most vultures, thus it is also known as the vulturine fish eagle. It also doesn't require thermals, it can flap its wings for as long as is necessary to get where it wants to go. Woo! Doin' it for themselves!

Image Gabriel Buissart
Hooded Vulture
It couldn't last, could it. Hooded vultures seem ugly in a whole new way. They look so refined, it's like they've gone to great lengths to achieve just the right look they were going for. They nest in trees in sub-Saharan Africa and are utterly unafraid of humans. Locals call them "garbage collectors" because of all the city waste they feed on. All I get are pigeons. Good.

Image: Kousik Nandy
Egyptian Vulture
This is potentially a beautiful bird with an alien head, but it's a vulture and does what vultures do so it's a filthy bird with an alien head. Aside from carrion they also eat insects which they fish out from dung. Also they eat the actual dung, so there's that as well. Apparently, faeces gives them all the nutrients they need for their facial pigmentation, so they seem to really value that alien head of theirs. On the plus side, they use stones to break large eggs, making them one of only a few birds that use tools. They are about 85 centimetres long with a 1.7 metre wingspan, which is small in this company. They have a wide range, southern Europe, northern Africa and west and south Asia, mostly in dry and rocky areas. Those in Europe fly south in the winter, up to 5,500 km and travelling as much as 500km a day.

Image: Dezido

This vulture is mentioned in the Bible and indeed, had a lot to do with Ancient Egypt. There is a vulture hieroglyph with meanings such as 'mother' and 'prosperous' for one. Also, it was used to represent Nekhbet, a patron mother goddess of the kingdom. It was also sacred to Isis, goddess of magic, motherhood and fertility. Egyptians felt that the huge wing span was an indication of being a good mother. The loving embrace of a vulture, right? Right. It's difficult to appreciate these days, but a creature that consumes not only the dead but also excrement could be extremely important in those times and in certain parts of the world. Egypt also had that kind of relationship with the dung beetle. The Aztecs also had a consumer of filth, a goddess called Tlazolteotl. Other people just think it's disgusting and always have, which is fair enough.

Image: Vishal Sabharwal
Red Headed Vulture
There were once hundreds of thousands of these vultures from Pakistan to Singapore. Their numbers started to fall some time ago, but then they were devastated by the same veterinary drugs that others of the region suffer from. It is now only found in Nepal and northern India, their population halving every couple years since the 90s until they are now in danger of extinction.

Image: Stephen Jones
White Headed Vulture
A medium sized sub-Saharan vulture. It prefers dry, wooded areas and doesn't fly quite as high as other vultures, so it is often one of the first to arrive at a death scene. They seem to go for medium sized corpses too, perhaps avoiding some of the larger species who would rather bee-line toward a really big, juicy platter. Species like our final vulture of the day.


Lappet Faced Vulture
Not the biggest vulture in Africa, that was the cape vulture, but this is the most powerful on that continent. They also have the aggression to indicate that they know it. This beast will take over feasts from other species and are more capable than they at tearing apart hide and muscle to get to the good bits. Many vultures will kill weak or injured prey if they can, but none will do so as much as this bruiser.

On the other hand, mothers are closely bonded to their child and they are often seen together as pairs. In southern Africa the word for 'lovers' is the same as that for this fearsome beast. It's interesting how cultural experience of these creatures, or lack thereof, has affected the way people think of them!

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Greetings, traveller.
You have come far to find me in this place.
The stench of mortality hangs heavy around you.
Now ask your questions and begone, before I tire of your presence.

I'm off for a nap now. Next time we'll check out the New World!

4 comments:

RbMommy said...

Very interesting article. I've gotta show this blog to my 13-year-old. He's gonna love it too. Thanks for sharing this. I'll definitely be back for more monstrosities!

Joseph JG said...

I'm glad you enjoyed it and I hope your youngster does, too!

Anonymous said...

Hello there,
I'm glad that my image of the 'Red Headed Vulture' could support your informative article.
Well Done!

Cheers,
Vishal Sabharwal
www.coloursofnature.in

Joseph JG said...

Hey! I'm glad you think it was used well, and big thanks for letting people like me get our hands on it!