Brown long-eared bats regularly utilise buildings roosting in undisturbed roof spaces either singly, in crevices and timber, or in clusters around chimneys and ridge ends.

[4] It hunts above woodland, often by day, and mostly for moths, but its diet also consists of earwigs, flies, and beetles, gleaning these insects from leaves and bark.

A study by Eklöf and Jones (2003)[6] demonstrated the ability of the brown long-eared bat to visually detect prey.

Under experimental conditions, brown long-eared bats showed a preference for situations where sonar and visual cues were available.

Brown long-eared bats have relatively large eyes and ears and it is likely that visual information and passive listening allow this species to detect prey in cluttered environments.