light, but its colour is more varying, its eyes brown and the species has a shorter tail and shorter legs. The brown snake eagle is of medium size relative to species referred to as eagles, however it is the largest member of the Circaetus genus. Of the living species in the Circaetinae subfamily, it is similar in size to the bateleur but much smaller than the Philippine eagle. Total length is from and wingspan is from , though wingspans of up to may possibly be attained. Known weights are between , with an average of around . Despite its fairly large size, this species has a relative small wing spread, being smaller winged than the bateleur and even the much lighter black-breasted snake eagle. The brown snake eagle's call is a hoarse, guttural , usually uttered in territorial displays at conspecifics and sometimes culminating in a crowing . Pairs also call a soft probably as a contact call at the nest. Biology The brown snake eagle is somewhat larger and more powerful than other snake eagles and consequently tends to take relatively larger prey. It seems virtually any reasonably sized snake, regardless of whether harmless or venomous is taken more or less indiscriminately. Like others in their subfamily, they have natural protection against bites, with thick-skinned legs. 3 out of 4 identified snake species recorded at a nest in Zimbabwe were venomous species, including boomslang, puff adder and black-necked spitting cobra. Most snakes taken here were decapitated before being brought to the nest. Large adult snakes were taken here, including a large puff adder weighing about . Even more impressive accounts are known of this species hunting adult black mambas, including specimens measuring up to at least . Hunting is typically from a tree perch or hillock, but also rarely sometimes from flight, and taken almost exclusively on the ground. Like most snake eagles, they quite often swallow their prey whole (though particularly large snakes are torn apart), but seldom do so in flight as do other snake eagles. Alternate prey is known to have included monitor lizards, toads, francolins, guineafowl and chickens as well as rats and perhaps other mammals. This species is solitary and even the breeding pair is rarely seen in the same place at any point of the year. Males do almost all known territorial display flights, which sometimes escalate from typical soaring into butterfly-like erratic