The influence of roost closure on the roosting and foraging behaviour of Eptesicus fuscus (Chiroptera: Vespertilionidae)

We used radio tracking and direct observation to determine the effect of roost closure on the roosting and foraging behaviour of big brown bats (Eptesicus fuscus) in maternity colonies near Ottawa. Individuals were site loyal, but after eviction they moved short distances to new roosts where they tended to produce fewer offspring. The time spent on the first foraging flight, the maximum distance travelled, and the use of feeding areas did not change with exclusion. The results suggest that bats roost to take advantage of site-specific factors that may increase reproductive success.