[order] FALCONIFORMES | [family] Falconidae | [latin] Falco cenchroides | [UK] Nankeen Kestrel | [FR] Crecerelle d'Australie | [DE] Graubartfalke | [ES] Cernicalo Australiano | [NL] Australische Torenvalk | [Authority] Vigors and Horsfield, 1827

Nankeen Kestrel determination

Members of the genus falco are mostly medium-sized falcons, but vary from the large peregrine falcon to the small American kestrel. The wings are long and pointed and used almost continuously during flight. The bill is short, powerful, and with a distinct 'tooth' on each side. Most falcons of this group have a black teardrop-shaped 'mustache' mark on each side of the head. Falcons are fastflying birds of open country and are famous for attaining high speeds as they dive from high altitudes to knock birds out of the air.

copyright: Nick Talbot

The Nankeen Kestrel is a slender falcon and is a relatively small raptor (bird of prey). The upper parts are mostly rufous, with some dark streaking. The wings are tipped with black. The underparts are pale buff, streaked with black, and the under tail is finely barred with black, with a broader black band towards the tip. Females tend to be more heavily marked and have more rufous on the crown and tail. Males have a greyish crown and tail, although the extent varies between individuals. Females are larger than males. Young Nankeen Kestrels closely resemble the adult female, with heavier markings. Its small size, rufous colouring, and hab/ts will distinguish it from any other raptor. In flight it is white below with black wing-tips and a black bar near the end of the tail. In the East Indian Islands it is likely to be confused with the resident Moluccan Kesterel (Falco moluccensis), but is a good deal paler than that species, especially when seen in flight.

Preferred habitats are lightly wooded areas and open agricultural regions and tend to be absent from dense forests. The Nankeen Kestrel's success as a bird of prey can be largely contributed to its tolerance for a wide variety of habitats and its ability to feed on a variety of foods and nest in a range of sites. It frequents open country, plains, cultivated fields and the like, and occurs commonly in towns and on islands off the coast. Although it prefers open country it is not confined to it, but will avoid dense forest or woodland. It has invaded cultivated areas cleared from forest. It is a common and noticeable little bird, and like other kestrels it flies 50 feet or so above the ground, turning into the wind at intervals and hovering with gently fanning wings and spread tail. It also hunts commonly from a perch, a tree branch or a pole. It tends to be gregarious, especially on migration, and can often be seen in small parties of five or six together. In this respect it is like the Common or Lesser Kestrels. In Eastern Australia it seems sedentary. It is a bold and confident little bird, quite common in large cities, where it will nest on buildings.

The main food of the Nankeen Kestrel is insects. It also takes at times small birds and small mammals. It has been known to kill a wood swallow in a hole in a tree. Generally it is a harmless and beneficial bird which should not be persecuted. Prey is located from a perch or by hovering a short distance above the ground on rapid wing-beats, using its fan-shaped tail as a rudder and keeping the head and body kept still. Once prey is spotted, the bird drops nearer to the ground until it is close enough to pounce. Some insects and birds may be caught in mid-air or snatched from tree branches.

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be increasing, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

The nuptial display resembles that of other kestrels, the pair flying or hovering close together near the nesting site, with the male sometimes diving at the female, accompanied by chattering calls. It breeds in tree hollows, rock ledges, on buildings, or in the old nests of crows or other raptors. A hollow tree is preferred when available, but when nothing else is available it will use the broken tips of tall ant-hills. The preparation of a tree hollow for the nest takes about three weeks, and the birds are said to carry pieces of rotten wood or bark to the chosen hollow in their talons. Four to six eggs are laid on consecutive days, or nearly so, and incubation begins before the completion of the clutch. Incubation is by the female only, and she is fed at regular intervals by the male during incubation. The incubation period is about 28 days. For the first two weeks after the young hatch the male does all the hunting. The female remains either in or near the nest hollow, and on seeing the male with prey will fly to meet him with fluttering wings, and later take the food to the young. After fourteen days the female takes part in hunting. The young fledge after about a month.

Resident and partly migratory populations; many pairs sedentary in temperate regions. Birds breeding at high latitudes and altitudes tend to winter in coastal and lowland areas; many migrate North, some (mostly females) reaching New Guinea and Indonesia, West to Java and North to Moluccas. Also irruptive movements to arid regions after good rains and to local plagues of prey species.

Range: Australasia : widespread. The Nankeen, or Australian Kestrel is a resident of Australia and the highlands of New Guinea (Oranje Mountains).