BODBIJL A (1997) Behaviour and feeding ecology of breeding Long-eared owls Asio otus in SE-Brant. LIMOSA 70 (3): 97-100.

Prey-items and behaviour of breeding Long-eared Owls Asio otus were studied in a ca. 340 ha coniferous woodlot near 100 Eindhoven (Fig. 1, Tab. 1) in 1989-94. The number of breeding pairs in the study area varied from year to year. Pellets were collected from under five nests in 1993 and one nest in 1994.
      Differences in diet among the five pairs studied in 1993 (Tab. 2) indicate non-overlapping hunting areas of the various pairs. The large fraction of Wood Mouse in pellets, combined with an evident peak in the number of breeding owls suggests (1) local preference of Longeared Owls for this prey and (2) fluctuations in the Wood Mouse population similar to those known for Common Voles.
      Observed behaviours seldom reported earlier were: (a) Owls extensively stretching muscles of wings, legs and toes prior to departure for their nocturnal hunt. (b) Males returning to nest sites within a few minutes after starting activity and then producing a very soft hooting call of very low frequency from various posts situated around the nest (Fig. 2). These calls, too soft to be heard at distances of more then 25 m, were given while the birds made pumping body movements. Once, a bird was seen at nine posts, constituting a full circle around the nest. The call was given eight to 15 times from each post with intervals of about one second, where after the bird flew to the next post with one or two audible wing flaps. Another time, only three posts were observed. (c) Two males chasing each other produced calls and when they approached the nest, a female started uttering the same calls.

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