Conspicuous, Nomadic, Opportunists… Black-shouldered Kites

By Dr Keith Hutton on February 8, 2012 in Other

Black-shouldered Kites are among Australia’s most conspicuous birds of prey. They are largely pearly grey and white and moderately common in the Sydney region. They frequently hover, often with feet dangling, or perch obviously on fence posts, power lines and the tops of vertical dead branches alongside roads in open areas. Malabar Headland and The Coast Golf Course at Little Bay are suitable places to look for them in the Eastern Suburbs where they have also been observed in Centennial Park.

An adult Black-shouldered Kite is a beautiful, immaculate, small grey hawk with a pure white head, body and tail, black shoulders and deep red eyes each set in a small black patch; their legs and the area of bare skin above the beak are bright yellow. Sexes are similar. When not hovering Black-shouldered Kites fly purposefully with quick, shallow wing beats broken by sailing glides on upswept wings, usually within twenty metres of the ground. Occasionally they will take advantage of thermals and soar high up in the sky. They are unlikely to be confused with any other kind of bird in the Sydney region.

Black-shouldered Kites are nomadic and irruptive opportunists that respond to food availability and consequently may be found throughout mainland Australia. They prefer grasslands with scattered trees, cereal stubbles, wide roadside verges, overgrown vacant land, suburban paddocks, coastal wastes, sports fields and golf courses. Similar closely related species that differ slightly but consistently in plumage characteristics, size, proportions and behaviour are found in PNG, Indonesia and Southeast Asia, India, Africa, Europe and North and South America.

Black-shouldered Kites eat mostly small mammals the size of a mouse, but baby rabbits, insects, small birds, reptiles and amphibians are also on the menu. Preferred hunting times are early morning and late afternoon, often around sunrise and sunset and occasionally at night. Hovering skilfully with tail down and wings beating almost back and forward is the usual method of hunting, but these birds also occasionally hunt from a perch. When attacking they raise their wings above their backs and, with legs extended, drop to the ground, sometimes checking to adjust or verify position before pouncing on to their prey.

The range and numbers of Black-shouldered Kites have increased since European settlement in Australia in response to development of cereal cropping and irrigated agriculture, and to the introduction and establishment of house mice. Black-shouldered Kites probably evolved as specialised hunters of small native mammals and now their main prey items are mice that regularly increase locally to plague proportions.

In more recent years no change in status of Black-shouldered Kites nationally has been noticed but there have been significant distribution changes in response to mouse numbers. Despite a reduction in native small mammals the future for Black-shouldered Kites in Australia appears to be secure as a consequence of land clearing and the ready availability of introduced house mice for food.