The whistling kite (Haliastur sphenurus) is a medium-sized diurnal raptor found throughout Australia (including coastal islands), New Caledonia and much of New Guinea (excluding the central mountains and the northwest).

A species of open or lightly wooded areas, whistling kites are typically found near water, at elevations ranging from sea level to 1400 meters.

[2] Whistling kites tend to be found singly or in pairs, but sometimes gather in larger groups, particularly during nomadic movements, at roost sites and at sources of plentiful food.

[3] Whistling kites are indiscriminate in their tastes, taking small mammals, birds, fish, reptiles, amphibians, crustaceans, insects and carrion.

[2][5] Those in Australia tend to take primarily live prey (except in the winter, when they subsist largely on carrion), while those in New Guinea are principally scavengers.

[3] The whistling kite's nest is a bulky platform made of sticks and lined with green leaves, placed in an upright fork of a tall tree—often a eucalypt or pine in a riparian area.

[2][3] In Australia, the birds generally breed between June and October in the south, and between February and May in the north, though they may nest at any time after rain providing there are adequate food supplies.