The white-backed vulture is currently facing a major population crash, and has declined by 63-89% in the last 40 years. In 1992, it was estimated there were 270,000 white-backed vultures. ĩ7% population collapse since the mid-1990s, caused by diclofenac. The only country with possible increases is Cambodia, where the drug is apparently unavailable. Catastrophic population collapse beginning in the 1990s has been caused by diclofenac, a drug used to treat livestock after eating decaying bodies containing this substance, the vultures succumb to kidney failure. ĭescribed in 1985 as "possibly the most abundant large bird of prey in the world", numbering millions. Population undergoing collapse due to the use of diclofenac. "Likely" estimate difficulties in quantifying have arisen due to taxonomic confusion. Population subject to extreme fluctuations within this band. Melbourne.Species by global population Common name Field guide to the birds of Australia, 6th Edition. Angus and Robertson, and the National Photographic Index of Australian Wildlife, Sydney. The Birds of Prey and Ground Birds of Australia. Handbook of Australian New Zealand And Antartic Birds Vol. The female incubates the eggs while the male provides food.īlack Kites are generally uncommon, but may be increasing in numbers after clearing and with increases in prey such as galahs, rabbits and starlings. In recent decades, it has increased greatly in numbers and spread into many new areas. The nest is a bulky cup of sticks, lined with softer material, and is placed in the fork of a tree branch (generally close to the trunk). White-tailed Kite Elanus leucurus As recently as the 1940s, this graceful hawk was considered rare and endangered in North America, restricted to a few sites in California and Texas. This involves loud calling, grappling of feet (talons), and tumbling or cartwheeling. As with other raptors, a ritualised aerial courtship display is performed by both sexes. Breeding behavioursīlack Kites nest in isolated pairs or in small, scattered colonies. The call is a descending whistle 'psee-err' followed by a staccato 'si-si-si-si-si'. They often gather and soar above fires, shooters or workers, watching for flushed prey. Both live and dead (carrion) prey is eaten. Black Kites also gather in flocks around bush fires, and eagerly pounce on small animals as these flee the flames. It also is a scavenger, and frequents tips in outback towns. The Black Kite preys on lizards, small mammals and insects, especially grasshoppers. The Black Kite is arguably the most numerous species of raptor in the world. The Black Kite's range covers the majority of the Australian mainland, as well as Africa, Asia and Europe. No other Australian bird of prey is seen in such large flocks. Although it is more normally seen in small groups, the Black Kite may form huge flocks of many thousands of birds, especially during grasshopper plagues. The Black Kite is found in a variety of habitats, from timbered watercourses to open plains, and is often observed in and around outback towns. Young Black Kites are generally lighter in colour than the adults, and have a comparatively shallower forked tail. The eye is dark brown and the bill is black with a yellow cere (area of skin around the nostrils). This feature gives the bird its alternative name of Fork-tailed Kite. The tail is forked and barred with darker brown. The plumage is actually dark brown, with scattered light brown and rufous markings, particularly on the head, neck and underparts. From a distance, it appears almost black, with a light brown bar on the shoulder. The Black Kite is a medium-sized raptor (bird of prey). The Black Kite is the most abundant raptor (bird of prey) in the world.
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