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Vultures 309

in trees. Most cliff-nesting species nest colonially while pairs of tree-nesting species usually
maintain individual territories, although some are loosely colonial.
Four Asian vulture species, the White-rumped, Indian, Slender-billed, and Red-headed are now
critically endangered and the Egyptian Vulture is endangered. In South Asia, vultures feed largely on
carcasses of cattle, many of which had been treated with the NSAID diclofenac, now known to be
extremely toxic to vultures. Although veterinary use of this drug has been prohibited, it is still easily
available as a human medicine drug and is very inexpensive. Nearly all other NSAIDs have proven to
be similarly toxic. Vulture-safe zones that provide drug-free carcasses are helping to slow the decline
and captive propagation of assurance populations of the three Gyps species is ongoing in India.
In Africa, four vulture species – the White-backed, Ruppell’s, White-headed, and Hooded – have
recently been classified as critically endangered and three – the Cape, Lappet-faced, and
Egyptian – as endangered. This precipitous decline has been primarily due to widespread direct
poisoning by poachers. Collisions with power lines and ritual use of vulture parts are contributing
to the decline.
Although protocols in this chapter are based on experience with California and Andean Condors,
King Vultures and Gyps vultures specifically, the methods described should work equally well with
other vulture species with adjustments for incubation and rearing periods and proportionate feed-
ing and weight gain amounts. See Chapter 20 for more information specific to hand-rearing
American Black and Turkey Vultures.

­ Criteria­for Intervention

Eggs or chicks that are neglected or compromised and cannot be returned to the parents – whether
due to poor parenting, interference by enclosure mates, accident, or weather extremes – are candi-
dates for hand-rearing. It is generally not advisable to hand-rear vultures to produce handleable
animals for educational programs as these birds invariably become quite aggressive when they
reach sexual maturity, greatly limiting their usefulness and diminishing their breeding potential.
Whether the choice to hand-rear is intentional or as a result of rescue, use of the strict isolation
rearing methods described below will prevent malimprinting on humans and produce behavio-
rally healthy adults.
Determining that an egg or chick requires intervention is usually straightforward, but the need
for this can often be avoided through good husbandry and subtle management techniques. If given
an appropriate, private nesting area, most vultures will prove to be excellent parents. Even so, it
may be desirable to artificially hatch and rear chicks, allowing multiple clutching to increase pro-
duction, as in the case of endangered species being reared for release to the wild. Occasionally,
parent birds are not able to care for the egg or chick. This is more often the case with inexperi-
enced, young parent birds and those that were hand-reared without adequate socialization with
conspecifics. Individual birds, usually males, may be overly aggressive with their mates, despite
proper rearing and experience. In any of these situations, birds may fail to incubate consistently or
brood and feed chicks adequately. They may also fight over these duties, risking egg breakage or
cannibalization of the chick. Tensions are highest and the risk of injury is greatest around the
times of egg laying and chick hatching. Parent birds that feel they must defend their nest site will
be more aggressive with each other in general and are more likely to break eggs or injure chicks.
A good nest box or platform design will allow close monitoring of eggs and chicks, through one-
way glass or closed-circuit television, while ensuring a sense of privacy and security for the par-
ents. Adults can be accustomed to feeding in a specific area at a specific time, ideally one in which
they can be secured and that is out of view of the nest area, thereby allowing eggs and chicks to be
checked directly without the parents’ awareness of this activity. This can facilitate removing eggs