Bats and Forestry
Ideal Homes for Bats
The majority of British bats evolved to live in trees. Bats use trees as roosts because they offer a wide variety of conditions that bats require at different times of year.
Bats and their roosts are all protected by law. Through sensitive and proactive woodland management, you can not only protect bats but also enhance the habitat for bats and a host of other wildlife.
Temperature and light are important factors when bats select roosts. Roost preference depends on the bat species, the time of year and the breeding status of the bat. Male bats and non-breeding females tend to prefer cooler conditions throughout the year, but breeding females prefer warmer roosts in spring and summer when raising a baby bat places high demands on their energy levels. Breeding females cluster together to retain body heat, but they also gain 'free' heat from tree roosts in two ways, to help them get through this challenging time:
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Selecting naturally warm sites, such as sheltered trees receiving sone sunshine during the day.
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Selecting highly insulated sites, such as a tree hole with a small space and thick wood surrounding it.
Because bats are so sensitive to light, heat and humidity, you will need to consider the impact of woodland management operations in the vicinity of trees with roosts.
How Bats Use Woodlands
The use bats make of woodland is influenced by the particular bat species, the season and the type and size of woodland.
Coniferous, deciduous and mixed woodlands can all be home to bats, providing there are suitable places to roost or feed.
In small to medium sized woodlands, noctule bats will use trees as roosts but they might forage up to 20km from the woodland at night.
At the other extreme, Bechstein's bats will both roost and forage in a suitable woodland of 25 to 50 hectares or more in size, and only rarely venture further afield.
Although Leisler's bats sometimes roost in houses in summer, they move to hibernate in woodland trees in winter. Greater and lesser horseshoe bats are unlikely to use trees as roosts, but frequently enter woodland to feed.
Often, woodland can be important at the end of the summer. Although resident in woodland all year round, male pipistrelles establish temporary mating roosts in trees, from where they will display to attract passing females.
Be aware that bats are also found in other structures within woodland, such as buildings, sheds and underground sites, for example mines and bunkers.
Bats Particularly Associated with Woodland
Bechstein's bat
Bechstein's bats most frequently roost in old woodpecker nest holes. Records so far indicate that oak and ash are important trees for roosts of this species. In general, they prefer wet woodlands with small streams. Further information on Bechstein's bats
Barbastelle
Barbastelle bats roost in trees year round, normally in ancient or old growth deciduous woods with substantial understorey. Their roosts are chiefly found in splits or behind loose bark. The bats move between roosts with great frequency, so a large number of damaged and dead trees are normally present in favoured woodlands. Further information on barbastelles
Natterer's bat
In summer, this species generally roosts in trees (both deciduous and coniferous), in buildings or bat boxes close to their feeding habitats. These may include broad-leaved woodland, hedgerows and treelines along agricultural land. Habitats used also include conifer plantations of, for example, Corsican and Scots pine. Further information on Natterer's bats
Noctule
Noctules are primarily tree dwellers and live mainly in rot holes and woodpeckers holes. A roost of breeding females can be particularly noisy on a hot summer's day. In late summer, single males establish mating roosts in tree holes. Further information on noctules
Lesser horseshoe bat
Lesser horseshoe bats seldom roost within woodland, but they enter wooded habitats to forage. Their maneuverable flight allows them to twist and turn between the trees and within dense vegetation, catching small moths and midges as they go. Further information on lesser horseshoe bats
Brown long-eared bat
Brown long-eared bats mainly roost in tree holes, buildings and bat boxes during the summer. Roosts in trees may be close to the ground, and the immediate surroundings of the roost can be more cluttered with vegetation than for some other bat species.
They prefer to forage in decidiuos woodland where they glean insects from leaves and bark. They have a slow, fluttery mode of flight. Further information on brown long-eared bats
This information, and more in depth guidance, is available in Woodland Management for Bats, published by the Forestry Commission for England and Wales in partnership with BCT, CCW and English Nature (Natural England).
Related downloads
A basic introduction to the legal protection of bats in the British Isles. Please note: This leaflet is in the process of being updated to reflect the 2007 amendments to the legislation.
This leaflet outlines the legislation which must be taken into account when working on trees.
A good practice guide published by the Forestry Commission for England and Wales in partnership with BCT, CCW and English Nature (Natural England)