The hunting behavior of Eastern Screech-owls (Otus asio)

We studied the nocturnal hunting behavior of eight radio-tagged Eastern Screech-owls (Otus asio; five females and three males) during the period from November 1994 through March 1995. Screech-owls selected low perches when hunting ((x) over bar = 1.66 m), presumably to obtain a clear view of the ground and an-unobstructed flight path to prey. Low perches may also improve the ability of screech-owls to hear and locate prey. Screech-owls used perches at different heights when hunting different types of prey and also tended to perch higher when moonlight was available, perhaps because increased light levels permit owls to rely more on vision. Only 8 of 35 attacks were successful, and this low success rate suggests that owls were more often attempting to capture small mammals rather than invertebrates. Male and female screech-owls exhibited similar hunting behavior, with no differences observed in the types of prey hunted or in giving up times. Weather conditions and season (early winter vs. late winter) had little effect on the hunting behavior of screech-owls.