Madagascar Fish-Eagle prey preference and foraging success

We investigated Madagascar Fish-Eagle (Haliaeetus vociferoides) foraging ecology to determine prey preference and the effect of fish abundance on fish-eagle foraging rates and foraging success. We observed fish-eagle foraging behavior at nine lakes in western Madagascar from May to August 1996. We sampled the fish population at each lake using gill nets and recorded fish weights and species. Introduced tilapia, Oreochromis spp. and Tilapia spp., made up the majority of both the gill net (66.3%) and fish-eagle catch (64.7%) in similar proportion, suggesting that the fish-eagle is an opportunistic predator. Consequently, replacement of native fish species by exotics probably has not been detrimental to the island's fish-eagle population. Male fish-eagle foraging success was positively correlated (P < 0.001) with number of fish species, suggesting that fish species diversity may affect fish-eagle foraging effectiveness.