The 7 species of New World Vultures are resident to the Americas. Despite many similarities, they are actually unrelated to the Old World Vultures. The New World Vultures are thought to have evolved from cranes, whereas the Old World Vultures have the same origins as hawks. Some recent taxonomic studies have cast doubt on whether the New World Vultures should be considered as raptors. In these taxonomies, they have been moved from the Falconiformes order to the Ciconiiformes order, as there is evidence that they are more closely related to Herons, Storks & Ibises than they are to Hawks & Eagles.
The Old & New World Vultures are considered to be one of the best examples of convergent evolution - similar species evolving from totally different origins. Similar to the Old World Vultures, the New World Vultures are carrion eaters, they have bald head & necks (other than a thin layer of down), strong bills & are very strong flyers. There are two obvious (well, almost) differences between the two types of vulture, the New World Vultures have no internal separation of the nostrils (so you can see right through the nostrils on the beak) & they have weak feet, more suitable for walking than killing & the hind toe is not functional. They lack a syrinx, similar to our voice box, so limited to grunts & wheezes. In size, the New World Vultures range from medium sized to very large. The Andean Condor is often considered the worlds largest land-based flying bird, in terms of overall size (the Marabou Stork may have a larger wingspan & the Wandering Albatrosses spend the majority of their lives on or over water).
They have broad wings, coupled with a large wingspan, this leads to effortless, elegant flight. Given a hot day with good thermals, can often stay in flight all day.
Several of the New World Vultures have habit of muting (or pooing) on their legs, this makes the naturally dark coloured legs look white. It is thought that this is possibly for cooling their legs (thought to be the reason storks, to which they may be related, do it) or as a level of protection from bacteria in the carrion they eat.
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In America, the vultures (especially Turkey Vultures) are often referred to as buzzards, while raptors of the buzzard (buteo) family are referred to as hawks.
Turkey Vultures (Cathartes aura) (and some other small New World Vultures) have a highly developed sense of smell, and are able to detect carrion by that sense alone, from very long distances. The carrion is detected long before it starts rotting too much, vultures will avoid eating badly rotten flesh, possibly because of lethal bacteria, & prefer fresh meat (in fact will often bathe after eating). The larger vultures have keen eyesight & a poorer sense of smell, relying on the smaller vultures to find the carrion & then chasing them off. Some of the larger vultures prefer to eat the parts that the smaller ones can't (such as the skin & tough tendons), leaving the rest for the smaller vultures. Early theories on the success of Turkey vultures included a highly developed sense of hearing able to detect the sound of flies around the carcass, the ability to spot small flesh eating rodents heading towards the carcass and an "occult" sense that humans could not detect. Other vultures do use sight to detect carrion, both directly & by observation of other vultures heading down towards the carcass.
Turkey Vulture : Least Concern (LC)
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The two species of Condor (California & Andean) are included in the New World Vultures. They are the worlds largest flying birds, both around 130cms (50") in length & 10kg (22 lbs) in weight. The 3 metre (10ft) wingspan of the Andean Condor (Vultur gryphus) slighly exceeds that of the California Condor (Gymnogyps californianus). The Condors only breed every other year, the Andean Condors lay two eggs & the California Condors only a single egg. The California Condor population dwindled to 21 birds (including wild & captive birds), in 1982 & it was decided to capture all of them & conduct an intensive breeding program, to save the bird from extinction. Reintroduction into the wild started 10 years later & by 1998, the number of birds had risen to 145, in total. In the year from June 2000 to June 2001, 4 California condors have been found dead from lead poisoning & a further 13 found to be seriously ill. It is thought that it was caused by the birds feeding off animals previously shot by hunters. Over that period, 56 California Condors were seen in the wild.
California Condor : Critically Endangered (CR C2a(i);D)
Andean Condor : Near Threatened (NT)
In American Indian mythology, it was believed that the sun was originally much closer to the earth & was in danger of burning it up. First the fox unsuccessully tried to pull the sun away in its mouth, accounting for the black inside of its mouth. Next the opossum unsuccessully tried to pull the sun away with its tail, accounting for the hairless tail. Finally a beautiful fully feathered vulture successfully pushed the sun away from the earth with its head, thus becoming bald for eternity.
The Pueblo Indians believed the vulture to be a symbol of purification, using the feathers of the Turkey Vulture to remove evil influences from people & objects.
The return of the Turkey Vulture after winter was believed to signify the end of frosts. They often return to their summer feeding grounds precisely on the Vernal Equinox, the winter migration often starts around the Autumnal Equinox.
Wearing a feather of a Black Vulture (Coragyps atratus - meaning "vulture dressed in black") was believed to prevent rheumatism.
A Wake of Vultures