Habitat selection, diet and interspecific associations of the rufous-tailed weaver and Fischer's lovebird

Abstract

We investigated habitat selection and diets of two co-occurring endemic bird species (rufous-tailed weaver, Histurgops ruficauda, Fischer's lovebird, Agapornis fischeri) and four other species with which they associated in mixed feeding flocks (red-billed buffalo weaver, Bubalornis niger, white-headed buffalo weaver, Dinemellia dinemellii, superb starling, Lamprotornis superbus, and Hildebrandt's starling, Lamprotornis hildebrandti) during the dry season in Serengeti National Park Tanzania. Mixed species flocks could facilitate food acquisition and/or act as anti-predator mechanisms. Five of the six species selected grassland habitat over Acacia habitat along transects. Analysis of species association, using Cole's coefficient of association, showed that both rufous-tailed weavers and superb starlings co-occurred with red-billed buffalo weavers. Superb starlings were negatively associated with Fischer's lovebird, Hildebrandt's starling and white-headed buffalo weavers. Diet analysis revealed that the rufous-tailed weaver, white-headed buffalo weaver, and red-billed buffalo weaver were generalists eating both insects and seeds, whereas Fischer's lovebird and superb starling were specialists, selecting only seeds and insects respectively. These data offer some support for the hypothesis that mixed species flocks facilitate mutual food searching. © 2007 The Authors.