1. One of the key threats to bats in Britain is loss of suitable roost
sites, but little is known about roost requirements for most species.
2. Roost selection in the brown long-eared bat Plecotus auritus was d
emonstrated by comparison of buildings used as summer roosts in north-
east Scotland with (i) random buildings in the same area, and (ii) a s
et of adjacent houses located in the same habitat. 3. Buildings contai
ning roosts were situated closer to woodland and water relative to the
random houses, and also had a greater area of woodland within a radiu
s of 0.5 km, but not at distances beyond this. This suggests that feed
ing habitat in the vicinity of the roost is important for roost select
ion. 4. When compared with adjacent houses, roosts were older, and had
roof spaces divided into more compartments, which were more likely to
be fully lined with rough wooden planking. 5. The temperatures inside
summer roosts (mean 17.9 degrees C) were significantly warmer than th
ose from random and adjacent houses (mean 16.7 degrees C). 6. These re
sults suggest that P. auritus is selective of its roosts, relative to
the houses available. 7. The selection of specific types of roosts by
P. auritus has implications for the management advice provided when ro
osts are threatened, and conservation actions should focus on efforts
to avert significant change to, or destruction of, roost sites or the
woodland in their vicinity.