Family: Accipitridae
Genus: Circaetus
Species: C. cinerascens

Western Banded Snake Eagles are small raptors that live across sub-Saharan Africa in riverine woodland. They form a superspecies with Circaetus fasciolatus (Southern Banded Snake Eagle).

Physical Description:

Western Banded Snake Eagles are gray-brown with white barring along the flanks, belly, and thighs. The cheeks and throat are pale in color. The tail is black and has a white tip and central band, and the flight feathers are barred with black trailing edges. There are white patches at the base of the primary feathers. Females are usually darker in plumage than males. The base of the beak is orange-yellow and the eyes and legs are yellow.

Juveniles are brown from above with a cream-buff underside and a dark breast. There is spotted and barring on the belly and thighs and the tail is light brown with a dark brown subterminal band. The cere is yellow and the legs are pale white-yellow.

Western Banded Snake Eagles often call when perched. Their main call is a low, croaking "kok kok kok kok ko ho". Listen to a recording.

Size:

Length: 50-58 cm
Wingspan: 120-134 cm
Weight: 1.1 kg

Habitat and Distribution:

They live in woodland, forest edges, and wooded savannah, often close to rivers, from 0-2,000 meters above sea level.

They are found in western Africa from Senegal, Gambia, and Cote d'Ivoire east through Nigeria, Democratic Republic of the Congo, South Sudan, Kenya, and Ethiopia. They also live in the south across Angola, Zambia, Mozambique, Zimbabwe, Namibia, and Botswana. Their total range spans 16°N to 19°S and 3,880,000 km². Adults are irruptive or local migrants, though movement of Western Banded Snake Eagles has been recorded in August-October in eastern Africa and they move with the rainy season in western Africa.

Diet and Hunting:

They eat small snakes, water monitors, lizards, amphibians, small rodents, fish, beetles, and tortoises. As their name indicates, they eat many snakes both venomous and non-venomous, which can be up to 75 cm long and are swallowed whole.

They still-hunt from a perch and take their prey on the ground or, as with snakes, in a tree.

Reproduction:

Breeding displays consist of soaring, circling, dives, tumbling, and claw-grappling. The main breeding season is from December-April in northeastern Democratic Republic of the Congo, though breeding activity has been recorded year-round.

The nest is 45-60 cm across and 15-25 cm deep, lined with green leaves, and placed in a tree close to water 9-18 m high. Clutch size is 1 egg. Incubation and fledging periods are unknown.

Conservation:

Western Banded Snake Eagles are threatened by development and habitat loss. However, they are currently listed as Least Concern by BirdLife International.

Taxonomy:

Circaetus cinerascens forms a superspecies with Circaetus fasciolatus (Southern Banded Snake Eagle). Genus Circaetus is closely related to the vulture group Aegypiinae and Dryotriorchis spectabilis (Congo Serpent Eagle).

The scientific binomial name comes from the Greek circus and aetos, which mean "harrier" and "eagle", and the Latin cinerascens which means "ashen", referring to color of the head and upperparts of Western Banded Snake Eagles.

Other Names:

Banded Harrier Eagle, Banded Snake Eagle, Smaller Banded Snake Eagle, Enkelbandslangenarend (Afrikaans), Brun Slangeørn (Danish), Kleine Grijze Slangenarend (Dutch), Jõgi-madukotkas (Estonian), Jokiköörmekotka (Finnish), Circaète cendré (French), Bandschlangenadler (German), Biancone cenerino minore (Italian), Obichouhiwashi (Japanese), Båndslangeørn (Norwegian), Gadozer bioalopregi (Polish), Águila Culebrera de Cola Blanca (Spanish), Tai Miraba Magharibi (Swahili), Mindre bandad ormörn (Swedish).

Video of a Western Banded Snake Eagle:

References:

http://avibase.bsc-eoc.org/species.jsp?avibaseid=4327F813018F6D37
BirdLife International (2012) Species factsheet: Circaetus cinerascens. Downloaded from http://www.birdlife.org on 19/04/2012.
http://www.eagle72.se/eagles_of_the_world/snake_eagles.htm
Global Raptor Information Network. 2012. Species account: Western Banded Snake Eagle Circaetus cinerascens. Downloaded from http://www.globalraptors.org on 19 Apr. 2012
http://ibc.lynxeds.com/species/western-banded-snake-eagle-circaetus-cinerascens
BirdLife International 2009. Circaetus cinerascens. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. www.iucnredlist.org. Downloaded on 19 April 2012.
http://www.kenyabirds.org.uk/banded.htm
http://www.namibian.org/travel/birds/western-banded-snake-eagle.html
http://www.planetofbirds.com/accipitriformes-accipitridae-western-banded-snake-eagle-circaetus-cinerascens
Ferguson-Lees, James, and Christie, David A. Raptors of the World. Houghton Mifflin Company, 2001.