Falco cenchroides

The nankeen kestrel (Falco cenchroides) is a raptor native to Australia and New Guinea. It is one of the smallest falcons, and unlike many, does not rely on speed to catch its prey. Instead, it simply perches in an exposed position, but it also has a distinctive technique of hovering over crop and grasslands. A species of the genus Falco, allied to a subgenus Tinnunculus. They were first described by Nicholas Vigors and Thomas Horsfield in 1827. Further descriptions—regarded as synonyms for the species—were published, Cerchneis immaculata Brehm, 1845, the later name Cerchneis unicolor by Alexander Milligan was published in Emu in 1904, that author's name appearing in the arrangement to a subspecies, Cerchneis cenchroides milligani, published by Gregory Mathews in 1912. The common names Mosquito Hawk, Kestrel, Windhover, Hoverer are cited at the Australian Faunal Directory. This bird is thought to be a very close relative of the Eurasian kestrel (Falco tinnunculus), and probably also the spotted kestrel (Falco moluccensis). It seems to have evolved from ancestral common kestrels dispersing to the Australian region in the Middle Pleistocene—less than 1 million years ago—and adapting to local conditions. A small, slim falcon (about 31 to 35 centimetres or 12 to 14 inches long), the nankeen kestrel is rufous or brown above and white or off-white below, with a black tail tip. Plumage varies considerably in detail, and some birds can look very scruffy, but the slim build, small size and distinctive straight-winged hovering habit make identification easy. The only other Australasian raptors to hover are the elanid kites, which are much lighter in colour and a little larger, and the brown falcon, which is much larger and more heavily built, and hovers only with difficulty. Altogether, the nankeen kestrel looks just like a pale, less patterned, and smaller derivate of the Eurasian kestrel, which it indeed is (see Gloger's Rule, Bergmann's Rule). A very common and easily seen raptor, the nankeen kestrel is found in Australia, New Guinea, and nearby islands, and is an irregular visitor to New Zealand. It occupies any type of land that is not too densely vegetated, but in particular temperate grasslands and open woodlands. In the tropical north and the sandy deserts of the west, it has a patchy and seasonal distribution. It can be seen in Western Australia on coastal cliffs and windy conditions. Also seen on phone lines and power lines. Like many Australian birds, it has no clear migratory pattern: in the grasslands of the south, established pairs are resident year-round, but many other birds migrate north during the austral winter, or roam the arid interior following food supplies. Typically seen singly or in pairs, they can aggregate into loose flocks of up to 30 when conditions are right. Pairs are typically monogamous and may or may not disperse to different areas during the non-breeding season. The nest is any convenient structure: a tree hollow, cliff ledge or disused corvid's nest, for example, and is not modified or added to by the kestrels. Diet is varied, with a large number of insects, but also small birds and reptiles, and in particular, small rodents, mostly mice. Nankeen kestrels are adaptable and hunt in a number of different ways: of these, simply perching in an exposed position (such as on a dead tree or a telephone pole) and watching for prey is the most common, but it is their habit of hovering motionless over crop and grasslands that is most distinctive.