Gliding slowly at low attitudes, or soaring high in the sky, the Whistling Kite is a graceful bird. It flaps with slow wing-beats and when gliding holds its wings horizontally but bowed downwards at the tip. As it flies it sometimes utters its loud whistling call but it does not twist its tail when manoeuvring.
The Whistling Kite is found throughout Australia, but it is most common in open wooded country near swamps, rivers, or the coast. Although rather sedentary, it will shift about, congregating on eruptions of prey in the inland and leaving during famines. It is also somewhat communal around large kills, but just as often forages alone.
Like other kites, it sails about searching for living or dead prey on the ground, swooping down and feeding on it there if it is too large to carry. Although adept at hunting – small mammals, reptiles, birds, fish, crustaceans and large insects – it is as much a scavenger, feeding on carrion of any sort including animals killed by traffic on roads.
Whistling Kites are opportunistic breeders, pairs sometimes courting in groups and tolerating on another’s nests in the same tree. Courting birds soaring about the nest tree without spectacular aerial manoeuvres but call much from high exposed perches or in flight. Most pairs return to use the same nest – of sticks lined with fresh green leaves – year after year, or even twice in a season, adding to its bulk every time. Like other kites, the female incubates 2-3 eggs and broods while the male hunts, and passes all food to the chicks when they are young.