African Goshawk (Accipiter tachiro)

African Goshawk

[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Accipiter tachiro | [authority] Daudin, 1800 | [UK] African Goshawk | [FR] Autour tachiro | [DE] Afrikahabicht | [ES] Azor Tachiro | [NL] Afrikaanse Havik

Subspecies

Monotypic species

Genus

Members of the genus Accipiter are small and medium-sized hawks, often called Sparrow-hawks or Goshawks. The females are almost invariably much larger than the males – in some cases weighing twice as much – a level of size dimorphism only exceptionally reached in any other genus Falconiformes. Their wings are short and rounded; the tail usually quite long. They are well adapted for flying through dense bush. Bird-catching Sparrow-hawks generally have long and slender legs, with slender digits, the middle one being especially long. Goshawks are usually larger, with shorter, thicker tarsi and digits and a shorter middle digit. Some smaller species have goshawk-like feet and vice versa, making it difficult on a world-wide basis to subdivide the genus on this or any other broad basis. Although many accipiters feed upon birds moreso than do other hawks, some species take many mammals, especially squirrels; others take lizards, frogs, snakes, insects, even snails. In these species the legs and digits are sometimes slender, but short. Accipiters are rarely crested, but some have very attractive colour patterns. Black phases are present, especially in the tropical species. One in Australia has the only pure white phase. Accipiter is the largest genus in the family, having about fifty species. It is present worldwide, but is especially rich in Papua-New Guinea, where a small island like New Britain may have three to five endemic species or distinct sub-species.

Physical charateristics

Dark slate grey, paler on the cheeks, becoming sooty on the mantle and lower back. The tail is blackish brown, with three large white patches on the central tail feathers, forming broken white bars when spread. The upper-wing coverts are blackish brown. Primaries and secondaries are dark brown, banded with black and white at the base of the inner webs. Chin and throat are white, mottled grey. The under side of the body, under-wing coverts, axillaries and under-tail coverts are white, barred with rufous. The sides and thighs are chestnut, lightly barred with white. The underside of the tail is grey, with three broad black bars. The under side of the wing quills are grey, darker towards tips, with three, four or five dark bars. The eyes are orange-yellow, the cere greenish yellow, and the feet yellow.
The female differs from the male in being larger, browner, and more heavily marked below (the bars being dark brown rather than rufous). The tail bars are less distinct, and more grey.
Immatures are browner still, show more white on the nape, and some pale edges to the feathers of the upper side. The tail is brown, narrowly tipped with buff, with four black bars, but without the white crossbars of the adult. Under parts are white to buff, heavily spotted on the breast and heavily barred dark brown on the flanks aud under-wing coverts, the thighs are closely spotted and barred with sepia. Flight feathers are grey below, shading to pinkish buff basally, broadly barred dark brown. The eyes are brown, the legs and cere greenish. This plumage develops into the adult by becoming more slaty above, the crossbars developing in the rail, and by developing more barring below, with patches of chestnut on thighs and flanks.
This is a very variable species, and has been split into several sub-species with regional colour variations.

Listen to the sound of African Goshawk

[audio:http://www.planetofbirds.com/MASTER/ACCIPITRIFORMES/Accipitridae/sounds/African Goshawk.mp3]

Copyright remark: Most sounds derived from xeno-canto


wingspan min.: 67 cm wingspan max.: 73 cm
size min.: 35 cm size max.: 40 cm
incubation min.: 28 days incubation max.: 30 days
fledging min.: 28 days fledging max.: 32 days
broods: 1   eggs min.: 1  
      eggs max.: 3  

Range

Africa : East, Southcentral, South. The African Goshawk is found in Africa south of the Sahara, in well-wooded and forested areas.

Habitat

The forest or woodland habitat, three pale bars across the tail, with sometimes a broad white tip, and the call, are good pointers.
This is generally the common large or medium-sized sparrow-hawk in the African forests. It lives in deep forest, secondary growth, river strips and, in East Africa, the denser savannahs and mountain forests.

Reproduction

At the onset of the breeding season both sexes perform a display flight, a hundred feet above the forest canopy, but sometimes much higher, circling slowly with bursts of wing-flapping interspersed with glides, and calling ‘kwit’. This is most often in the early morning. Sometimes the wing flaps are slow and measured, almost harrier-like (chiefly males). They also perch on a branch at treetop level and call, in the morning and evening (if the call comes from thick cover it is likely to be a Robin-chat mimicking the Goshawk).
Nests are constructed annually, both sexes taking part, but sometimes an old nest is refurbished. It is made at any height from twenty to sixty feet above ground, well concealed in a thick-leaved tree. It is a small structure, up to two feet across and three feet deep. The cup, about nine inches across by three inches deep, is lined with finer sticks and green leaves.
Two or three eggs are laid at three-day intervals. They are white or greenish white, sometimes sparsely marked with brown and lilac. The breeding season normally coincides with the latter part of the dry season, but sometimes extends well into the wet season.
Incubation is carried out by the female only, and the period is 28 to 30 days. She sits very tight, and only leaves the nest about twice a day for brief spells. She is fed on the nest by the male.
The young hatch at two, three, or even four-day intervals, resulting in considerable variation in size. Feathers first show through the down at about fourteen days and they are full-feathered by twenty days. They attempt to tear up prey by themselves from six days onwards, but continue to be fed by the female up to 28 days, less frequently towards the end of the fledging period. They make their first flight from the nest tree at about 32 days.
The female broods the young closely in the early stages. and thereafter remains in the vicinity of the nest much of the time. The prey in the early fledging period is brought by the male, and the female consumes what the young do not eat. The male does not stay to feed the young even when he arrives on the nest in the female’s absence, and seldom visits the nest when she is there. Several kills may be brought in a day. In the early stages the female will leave the nest to receive prey from the male, and in the later stages she too takes part in killing and bringing prey for the young. The female roosts in the nest with the young in the early fledging period and the male in a tree not far away.
After the young make their first flights they return to roost in the nest or in the canopy of the tree above it, for up to two weeks. Thereafter they will remain in the neighbourhood of the nest for up to two months.

Feeding habits

Mostly birds, some mammals, and the rest occasional lizards, frogs and insects. By weight mammals would probably form a greater proportion of the food. Mammals as large as a full-grown mole rat, and birds as large as six-week-old domestic poultry are taken. The birds are mainly those of the forest, sometimes fledglings. It is a bold and successful poultry thief in forest villages. It takes a fair proportion of its food – mammals, frogs, and insects on the ground.

Video African Goshawk

httpv://www.youtube.com/watch?v=0wuCGxXSR4M

copyright: Josep del Hoyo


Conservation

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). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it is not believed to 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.
It remains inside heavy growth most of the time, but will cross open spaces, particularly in the early morning and evening when it catches much of its prey. It uses lines of trees or hedges as cover for hunting purposes, flying along them and suddenly over or through them to surprise prey beyond. It frequently perches near a waterhole in the forest, to catch small birds coming to drink. Inside the forest it makes short flights from tree to tree, flying low among the trunks and flicking up at intervals on to a perch. When hunting it sometimes crashes into and through dense vegetation, making a great commotion, with little regard for its own well-being. Wherever it occurs it is resident and sedentary, and a pair will frequent the same small area of forest day in, day out. The home range of a pair is no more than one-and-a-half to two square miles of forest in East Africa.
African Goshawk status Least Concern

Migration

Sedentary

Distribution map

African Goshawk distribution range map

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