Medium-sized to large eagle-like raptors. They can be distinguised from other eagles by their large heads, large yellow eyes and unfeathered, heavily scaled, lower legs.

They have broad and long wings with fingers on the tip, while the tail is of medium length. They hunt from a perch or in soaring flight. Eyesight is adapted for locating prey from height. Their food mostly consists of snakes which are grasped in their short but powerful toes and are usually swallowed whole.

The bateleur is an abberant snake-eagle with dark eyes, which feeds on a variety of small animals and even carrion.

They are not immune to snake-venom and may be immobilised by the poison, some are appearently blined by the venom of spitting cobras.

They are monogamous, generally laying just one egg in a small stick nest lined with green leaves. Incubation is mostly done by the female, whereas care of the young is taken up by both sexes. Large snakes are taken to the nestlings in the talons but smaller ones are carried in the stomac with the tail prottruding from the bill. The tail is then grabbed by the young bird and pulled out.

Circaetus = harrier-eagle (from greek 'kirkos' = 'harrier' and 'aetos' = 'eagle')
Terathopius = pretty face
pectoralis = refers to the chest
cinereus = grey or ashy (not accurate as the plumage is brown)
ecaudatus = refers to tailless appearance

Wikipedia

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