Abstract/Summary

An animal’s visual field is the three-dimensional space around its head from which it can extract visual information at any instant. Bird visual fields vary markedly between species, and this variation is likely to be driven primarily by foraging ecology. We used the ophthalmoscopic reflex technique to determine the binocular visual fields of African Harrier-hawks and compared this with similar data available for other species from the Accipitridae family (Gypaetinae, Circaetinae, Aegypiinae, Aquilinae, Accipitrinae, Buteoninae). African Harrier-hawks are distinct among Accipitridae with respect to the degree of binocularity present in the upper portion of their visual field. We suggest that this distinctive binocular field topography is related to the African Harrier-hawks’ foraging strategies and prey location behaviours and are associated with their double-jointed ankle/intertarsal joints.