4-6-2019 LINYANTI CAMP, BOTSWANA - AFRICAN HAWK EAGLE (Aquila spilogaster)

The African hawk-eagle (Aquila spilogaster) is a large bird of prey. Like all eagles, it belongs to the family Accipitridae. This species’ feathered legs mark it as a member of the Aquilinae subfamily. The African hawk-eagle breeds in tropical Sub-Saharan Africa. It is a bird of assorted woodland, including both savanna and hilly areas but the tend to occur in woodland that is typically dry. The species tends to be rare in areas where their preferred habitat type is absent. This species builds a stick nest of around 1 m (3.3 ft) across in a large tree. The clutch is generally one or two eggs. The African hawk-eagle is powerfully built and hunts small to medium sized mammals and birds predominantly, occasionally taking reptiles and other prey as well. The call is a shrill kluu-kluu-kluu. The African hawk-eagle is considered a fairly stable species and a species of Least Concern per the IUCN.

The African hawk-eagle is uncommonly aggressive and bold predator. Their primary hunting tool is their powerful feet. In general, their sneaky foraging techniques recall a huge Accipiter. In terms of agility and hunting prowess, especially in terms of their short-distance flight after prey, they are also somewhat reminiscent of an Accipiter. Mostly the African hawk-eagle engages in still-hunting, wherein they scan from prey from an inconspicuous perch for a long period. When prey is spotted, the hawk-eagle engages in a low level dash from their perch in cover. They often uses cover to cloak their approach almost up the point where they strike. While it has been claimed that their flight is “silent”, it would presumably be more correct to say that the hunting hawk-eagle engages in minimal flapping flight so as to not alert prey to their approach. Often, the hawk-eagles wait near prey-concentrated areas, such as waterholes and among riparian trees for birds to come to drink or by clearings that birds frequently cross. African hawk-eagles may too quarter above the ground and seize any prey they surprise. They are capable of sometimes taking birds on the wing but usually prefer to catch them on the ground and may force avian prey intercepted in the air back to the ground. Often terrestrial birds are taken right around the moment they alight. In some instances, prey may be chased, even on foot, into thickets. African hawk-eagles have seldom been recording engaging a stoop from soaring flight to capture prey. Pairs of African hawk-eagles often hunt together and in these circumstances seem to engage in deliberate cooperation, one distracting, the other striking. They share this tendency for hunting in pairs with their sister species, the Bonelli's eagle, which has been implied to engage in tandem hunts possibly for sociosexual pairing reasons rather than for obtaining larger or more difficult prey, as is typically assumed of tandem-hunting raptors. One tandem hunting pair of African hawk-eagles appeared to remarkably make use of a mesh fence to drive guineafowl into in a cunning strategy to prevent their escape. Yet another pair of African hawk-eagles appears to derive much of its prey by regularly and opportunistically perching in a tree holding a fruit bat colony.

4-6-2019 LINYANTI CAMP, BOTSWANA - AFRICAN HAWK EAGLE (Aquila spilogaster) PHOTO COURTESY OF MRS VALERIE FISHER

https://en.wikipedia.org/wiki/African_hawk-eagle

4-6-2019 LINYANTI CAMP, BOTSWANA - AFRICAN HAWK EAGLE (Aquila spilogaster)

The African hawk-eagle (Aquila spilogaster) is a large bird of prey. Like all eagles, it belongs to the family Accipitridae. This species' feathered legs mark it as a member of the Aquilinae subfamily. The African hawk-eagle breeds in tropical Sub-Saharan Africa. It is a bird of assorted woodland, including both savanna and hilly areas, but they tend to occur in woodland that is typically dry. The species tends to be rare in areas where their preferred habitat type is absent. This species builds a stick nest of around 1 m (3.3 ft) across in a large tree. The clutch is generally one or two eggs. The African hawk-eagle is powerfully built and hunts small to medium-sized mammals and birds predominantly, occasionally taking reptiles and other prey as well. The call is a shrill kluu-kluu-kluu. The African hawk-eagle is listed as Least Concern by the IUCN, but a study in 2024 showed that this species is experiencing a severe population decline of ~91%, suggesting it be listed as critically endangered. 

The African hawk-eagle has a somewhat small head but one that protrudes quite well due its quite long neck and relatively prominent beak. Furthermore, the species possesses a longish tail, with long and somewhat slender feathered legs and has large, robust feet. Although African hawk-eagles occasionally take to perching in the open, they usually are somewhat obscured for much of the day within the cover of foliage and often perch relatively low down in tall trees. The wing tips tend to fall a bit short of the tail tip. The adult African hawk-eagle evidences a fairly pied look with slate black-grey coloration above and whitish coloration below. At a distance, they may appear purely black-and-white but at close range they show sparse but extensive white flecks on the mantle and wing coverts. Occasionally, a greyer patch may be apparent on the folded secondaries of perched or sitting birds. The tail of an adult is grey with thin dark bars, a broad subterminal band and a white tail tip. 

The adult hawk-eagle's underside is white with bold but small and sparse drop-like blackish streaks. As was noted in a 2010 study, in a usual instance of plumage sexual dimorphism for an Aquilinae eagle, the underside tends to more sparsely marked on adult males and more densely marked on adult females to such a degree that an experienced observer may be able to sex individual African hawk-eagles despite the two sexes being similar in size. The adult African hawk-eagles has whitish coloring on the thighs and the crissum. The juvenile of the species is highly distinct from older hawk-eagles. Juveniles are moderately dark brown above with some pale edging, a slightly black-streaked head and a more clearly barred tail than adult hawk-eagles. The underside has a tawny-rufous base colour. When juvenile African hawk-eagles present black shaft streaks below they are usually only obvious on the flanks and they can border on being absent. Once developing as an immature at two to four years old, the upperside becomes progressively darker, the underside paler and more streaked and a subterminal tail band forms. At four years of age, as in related species, the African hawk-eagle becomes fully mature. The eyes of adult hawk-eagles are rich yellow while those of juveniles are hazel-brown while the cere and feet at all ages range from dull to somewhat brighter yellow.