The brown long-eared bat or common long-eared bat (Plecotus auritus) is a fairly large European bat. It has distinctive ears, long and with a distinctive fold. It is extremely similar to the much rarer grey long-eared bat which was only validated as a distinct species in the 1960s.
An adult brown long-eared bat has a body length of 4.5-4.8 cm, a tail of 4.1-4.6 cm, and a wing length of 4-4.2 cm. The ears are 3.3-3.9 cm in length, and readily distinguish this from most other bat species.
They are relatively slow flyers compared to other bat species.
It is found throughout Europe, with the exception of Greece, southern Italy and southern Spain. The UK distribution can be found on the National Biodiversity Network website.
This species appears to prefer caves as roosting sites, but roosts in trees holes, buildings and bat boxes, as well. The roosts in trees may be close to the ground.
It hunts above woodland, often by day, and mostly for moths, gleaning insects from leaves and bark. This is one of the bats for which eyesight is more important than echolocation in finding prey.
Echolocation is used to find prey. The frequencies used by this bat species for echolocation lie between 27–56 kHz, have most energy at 45 kHz and have an average duration of 2.5 ms.