Breeding behaviour and diet of the Crowned Eagle Stephanoaetus coronatus in western Tanzania

Abstract

The aim of the current study was to reveal the breeding ecology of Crowned Eagles in western Tanzania through constant daytime monitoring. The breeding circumstances of three resident pairs in the focal study area suggest that the breeding cycle of the species is seasonal, because they lay eggs in the dry season, so that fledging occurs in the rainy season. One pair brought a total of 88 prey items (a minimum of 80 prey individuals) during the breeding period from nest-making to the point at which the nestling was about to fledge at 106 days old. Prey animals comprised three vertebrate taxa (mammal, reptile and bird), of which mammals dominated, ranging over primates, rodents, carnivores, hyraxes and bovids. Diversity of prey taxa increased in the later stage of the nestling period. As well as breeding periodicity and prey selectivity, I describe details of some novel behaviours related to breeding ecology of the species, such as nest material delivery, copulation, feeding behaviour, unilateral eye closure, alert behaviour and defensive behaviour.

Keywords: breeding behaviour, Stephanoaetus coronatus, unilateral eye closure