[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Geranoaetus melanoleucus | [authority] Vieillot, 1819 | [UK] Black-chested Buzzard-Eagle | [FR] Buse aguia | [DE] Agula | [ES] Aguila mora | [NL] Grijze Arendbuizerd
Subspecies
Monotypic species
Genus
Members of the genus Geranoaetus are large hawks, about the size of a small eagle; in which the female is much larger than the male. They have long, broad wings, and a short, almost wedge-shaped tail. The feathers of the crown and upper back are slightly pointed. The breast feathers are lengthened and overhang those of mid-section, from which they differ in colour. Immatures are very different in colour and have a longer tail. The genus is quite closely related to Buteo, but is also close to various neotropical sub-buteonines such as Buteogallus and Leucopternis. One species remains, in open country of western and southern South America.
Physical charateristics
The head, centre of back and tail of the adult are bluish black, the feathers at the back of the neck and upper back are lengthened and pointed. The tail is tipped with greyish white. The shoulders and upper wings are dark grey, finely barred with black, the ground colour being blacker at the ends of the primaries. The sides of the head and throat ar a paler bluish black. The chest is bluish black, with long and pointed feathers that overhang the feathers of the belly. The rest of the under parts are dull white, finely barred with black. The eyes are hazel brown, the bill black, tipped with yellow at base, and the legs yellow. It tends to be a little smaller in the north. The upper parts of the immatures are similar to those of the adult but, lacking the clear grey areas on the shoulder, appear more dingy there and throughout. The tail is considerably longer than that of the adult, grey or brown with numerous narrow black bars. The underside is very different from that of the tawny or deep buff heavily marked with longitudinal black spots that gradually become bars on the lower abdomen on the thighs. The change to adult plumage is prolonged and gradual.
Listen to the sound of Black-chested Buzzard-Eagle
[audio:http://www.planetofbirds.com/MASTER/ACCIPITRIFORMES/Accipitridae/sounds/Black-chested Buzzard-Eagle.mp3]
Copyright remark: Most sounds derived from xeno-canto
| wingspan min.: | 175 | cm | wingspan max.: | 200 | cm |
| size min.: | 62 | cm | size max.: | 80 | cm |
| incubation min.: | 28 | days | incubation max.: | 33 | days |
| fledging min.: | 0 | days | fledging max.: | 0 | days |
| broods: | 1 | eggs min.: | 1 | ||
| eggs max.: | 3 |
Range
South America : Venezuela to South Chile, Southeast. It ranges in the Andes from northern Colombia south to the tip of Tierra del Fuego and is found additionally in the pampas of Argentina north into the grassland ecosystems of southeast Brazil
Habitat
The Grey Eagle-Buzzard is found in open country or in thin, dry woodland from the mountains of Venezuela south to Tierra del Fuego. North of Peru it is a bird of open mountain country, and quite rare. In Peru it is common in the rolling open hills near the coast, as it is also in the steppe country of western Argentina.
Reproduction
In the Andes, the nest is placed very high on cliffs. In Chile the birds begin to repair the nest in August or September. Where there are no cliffs, the Grey Eagle-Buzzard nests in trees, preferably in the tops of tall ones, but at times in lower bushes or even, on the ground. The nests are large, often used for many years, and contain, typically, two eggs.
Feeding habits
The diet of Grey Eagle-Buzzard is mainly mammals including skunks, although some insects and even carrion are eaten. Mammals account for almost 95% of its prey which it searches for on the wing, generally preferring habitats that allow good visibility. It is particularly reliant on the introduced European Rabbit; in one study this animal accounted for 44% of its prey items and 82% of its biomass intake.
Video Black-chested Buzzard-Eagle
httpv://www.youtube.com/watch?v=i0Tzb1s-h98
copyright: Max Roth
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). The population trend appears to be stable, 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 may be moderately small to large, 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.
Migration
No known movemnts
Distribution map
