HABITAT EXPLOITATION BY A GLEANING BAT, PLECOTUS-AURITUS

The brown long-eared bat, Plecotus auritus, differs from most other Pa laearctic bats in having broad wings and long ears, which are linked t o its slow flight, and its ability to hover and thus glean insects fro m surfaces. Previous studies have suggested a relation between intersp ecific variation in morphology of bats, particularly the shape of the wing, and differences in foraging behaviour. It might be predicted the refore that the foraging behaviour of P. auritus would differ from oth er Palaearctic species that have been studied. To examine activity pat terns and habitat use, 16 P. auritus were radio-tracked from six roost sites in northeast Scotland. Differences in behaviour compared to oth er Palaearctic species were found in the nocturnal activity pattern, h abitat use and distance travelled to foraging areas. Plecotus auritus emerged later than other sympatric species, at around 55 min after sun set, and remained active throughout the night, with a generally unimod al activity pattern. Individual bats used a series of feeding sites, t o which they returned regularly, and sometimes shared with others from the same roost. Plecotus auritus foraged exclusively in woodland and around individual trees. The bats displayed a preference for deciduous over coniferous woodland, probably reflecting higher insect availabil ity in the former. Hedgerows, tree lines and fence lines were used as commuting routes between roosts and feeding sites. Bats travelled up t o 2.8 km from the roost site, but spent most time foraging within 0.5 km of the roost; although males foraged further from the roost than fe males. The foraging behaviour of P. auritus reflected the morphologica l specializations of this species, but displayed a degree of intraspec ific flexibility. Deciduous woodland in the vicinity of roost sites ap peared to be key foraging habitat for P. auritus.