NOCTURNAL BEHAVIOR OF AFRICAN FALSE VAMPIRE BAT (CARDIODERMA-COR)

Nocturnal behavior of the African false vampire bat (C. cor) was studied in bushland in S Kenya, E Africa. Observations were made with a night-viewing device, and work was concentrated on the foraging strategy. This bat roosts in hollow baobab trees in groups of up to some 80 individuals. At night each bat occupies an exclusive foraging area. Individuals spend considerable time singing and establishing their exclusive areas during the March-April wet season when food is abundant; these areas have greatest survival value toward the end of the long May-Oct. dry season, when food is in short supply, foraging occupies nearly the entire night, and singing is infrequent. Nocturnal time budget is characterized by long periods spent perching in low vegetation and listening for terrestrial prey. Flights to capture prey and between perches are brief and short, usually lasting less than 5 s and covering less than 25 m. Food is typically captured on the ground, and consists primarily of large, ground-dwelling beetles, but centipedes and scorpions, and on rare occasions small bats are also taken. During parts of the rainy seasons leaf gleaning and aerial captures of insects are important; at these timed katydids (Tettigoniidae), locusts (Locustidae), and sphinx moths (Sphingidae) are major food items. Pronounced seasonal shifts in foraging behavior associated with the bimodal pattern of rainfall are discussed, and the evolution of the bat''s unusual stype of foraging is considered.