diagnostics

80-90 cm, 3.7-4.5 kg. An unmistakeable, large, jet-black eagle with distinctive white markings. The sexes are alike in plumage colouration, although the female is larger and heavier. The back and rump of both sexes are white with a narrow ‘V' extending from the back towards the head on either side of the mantle. The bill is grey with a yellow cere, gape and lores. The eyes are dark brown with a yellow orbital ring. In flight the wings are distinctly narrowed basally, with bulging secondaries and a prominent large pale patch at the base of the primaries (Simmons 2005).

trophic

Verreaux's Eagle is a solitary nester that builds a massive stick structure on a rocky outcrop or cliff, or more rarely in a tree or on a power pylon. Utilisation of pylons is on the increase in the Karoo (AR Jenkins pers. comm). The species pair-bonds for a number of years, although mate changes may occur more often than recorded (AR Jenkins pers. comm). Juveniles disperse from breeding areas, while adults show a strong fidelity to their breeding territories (Gargett and Mundy 1990). Availability of prey seems to be the main determinant of timing of breeding and breeding density (Gargett and Mundy 1990). Typically, birds breed from April with a single nestling fledging in October/November (Davies and Allan 1997). A generation length of 17.3 years is the mean of two calculated values derived from published and/or extrapolated estimates of mean age at first breeding, maximum longevity in the wild and mean annual adult survival (BirdLife International 2014).

This eagle feeds mainly on Rock Hyrax  although, in common with other raptors, it is an opportunistic predator that will also take medium-sized mammals, large birds and carrion (Simmons 2005). Predation of hyrax varied from 70 to 180 hyraxes per pair per year and has been estimated to exceed 350 elsewhere (Gargett and Mundy 1990, Davies 1999). Paradoxically, the breeding performance of Verreaux's Eagle shows an inverse relationship with rainfall (Allan 1988), as more hyraxes become available to eagles when they are forced to move further from their refuges to find food during drought (Davies 1994). Populations do not show good correlation with fluctuations in hyrax numbers (Davies and Ferguson 2000), because the eagles are able to switch to alternative prey items when hyraxes are scarce. Birds in the Strandveld on the West Coast rely heavily on Angulate Tortoise Chersina angulata and Molerats Cryptomus and Bathyergus spp. (M Murgatroyd unpubl. data).