Large raptors are ecologically unique, are more sensitive to disturbance and are more threatened than most birds of prey. Declines in large tropical forest raptors, such as Philippine eagles Pithecophaga jefferyi, could have significant impacts on the numbers [17] and behavior [74] of their prey, with further changes possible through trophic cascades [78]. Given their potential importance, there is a substantial but mostly unmet need for research on raptors as population control agents, particularly in agricultural and tropical ecosystems.