Brown Long-eared Bats

Plecotus auritus (Bat of the year 2022-23 by BatLife Europe)

Description and identification

Long-eared bats are unmistakeable due to their extremely long ears. Bats observed roosting however are not so easy to identify as their long ears are tucked safely away under the wings leaving only the tragus (inner ear) visible which can lead to bats being misidentified as other species.

The only species in Great Britain which can cause confusion is the very rare grey long-eared bat which is restricted to the southern counties of England and South Wales. An experienced handler should have no difficulty separating the two species. The brown long-eared bat is predominantly a woodland specialist but will also be found in parks and large gardens where there is a good degree of tree cover.

Status and distribution

The brown long-eared bat is widespread throughout Great Britain and Ireland except for the far north of Scotland. Only the common and soprano pipistrelle are likely to be more abundant. In Nottinghamshire the brown long-eared bat has a wide distribution throughout the county.

Conservation

Protected in the UK under the Wildlife and Countryside Act, 1981. Priority Species under the UK Post-2010 Biodiversity Framework. European Protected Species under Annex IV of the European Habitats Directive.

Roosts

The majority of known maternity roosts in Nottinghamshire are in buildings but trees and bat boxes are also used. A typical roost will be in an older building with a large enclosed roof space and slate roof tiles.

Traditional brick barns with pantile roofs and churches have also recorded roosts. A typical maternity colony will have 20-30 bats but can be as few as four and as many as 80. Males generally roost alone but have been recorded roosting with other males (seven have been found together in a bat box). Tree holes are also used and may be extremely shallow and exposed as shown in the photograph on the next page.

In winter, brown long-eared bats can be found in the same locations as the summer roosts. The type of building used for raising young often also provides suitable conditions for hibernation e.g. cellars, gaps in thick walls and crevices in large roof timbers. Tree holes, caves, tunnels and other underground sites are also used.

Food and foraging

Moths make up a high proportion of a brown long-eared bat’s diet but they also eat other invertebrates including flies, spiders, beetles, earwigs etc. Brown long-eared bats have broad wings which allow for a slow and manoeuvrable flight pattern. They are capable of hovering on the edge of a tree canopy where they will glean prey from the surface of a leaf or even take food from the ground. As with all our other bat species they will use echolocation calls to locate their prey but unlike other species they will often just rely on the incredible sensitivity of their huge ears. Some moth species have evolved the ability to hear a bat’s call as a defence strategy against being eaten. To counteract the moth’s defences, a brown long-eared bat will either call very quietly or remain silent and listen for the sounds of movement from insects on vegetation. Their quiet call is one of the main reasons why they go undetected during bat detector surveys even in areas where we are positive that they are present.

Click below to play a video with time exspanded and heterodyne bat echo location calls.