 in length), but will also prey on lizards, insects, small mammals and frogs.It mainly hunts from a perch or by hovering or searching the ground, stalking prey on the wing and then parachuting slowly to the ground to capture its prey.The species has also been found to be highly dependent on seasonal fluctuations in small mammal prey availability, with its numbers increasing in accordance with booms in small mammal abundance in the Serengeti National Park.