Bats

Thomson Ecology is highly experienced in bat surveys. If you suspect you have bats on a development site, the earlier you contact us the better in order to minimise any delays to your project.

Ecology and Conservation status

There are some 17 species of bats in the UK, some of which are very rare.
All British bats are nocturnal, spending daylight hours in bat roosts before emerging at night to forage for insects.
Bats hibernate during the winter in hibernation roosts and then the females gather in maternity roosts during the summer months to have their young. Bat habitats are varied– buildings, trees, bridges, caves, mines. They forage in areas rich in insects and may move around their home range using hedgerows and other linear features as a guide.
Bat populations have declined considerably in the UK over the last century.

Protection and Legislation

Bats and bat habitats are fully protected by both the Wildlife and Countryside Act 1981 and the Habitats Regulations.
Seven species of bat (Barbastelle, Bechstein’s, Noctule, Soprano pipistrelle, Brown long-eared, Greater horseshoe and Lesser horseshoe bat) are Priority species under the UK Biodiversity Action Plan and have also been adopted as Species of Principal Importance in England under Section 41 of the NERC Act 2006.

Licences and Surveys

A protected species licence will be required whenever disturbance of bats or damage to their roosts is likely to occur. The protection of bat roosts applies even if no bats are present at the time of development.
In practice, this means that surveys can only be carried out by a licenced ecological consultant. If ecological mitigation is required, a second licence application will be needed, accompanied by a detailed method statement setting out the activity to be carried out under the licence. The licence will only be granted for reasons of overriding public interest and it must be shown that the favourable conservation status of the bats is maintained and that there is no satisfactory alternative to the proposed development.

Mitigation

By far the best option is to preserve the existing bat roosts and habitats. This may be achievable if you involve ecologists at an early stage. Bat roosts and foraging patterns can then be identified and plans modified to accommodate them.
However, if existing roosts need to be modified or destroyed, then the bats must be protected, usually by appropriately timing the works for when bats are not roosting, and the roost must be replaced or reinstated. It is critical to retain the foraging and commuting habitat as well as the roosts. Bat boxes and even bat houses can sometimes be options.
Careful consideration will also need to be given to artificial lighting as this disrupt bats foraging patterns.
When mitigating for wind farms, it is important that foraging routes are also considered in order to avoid the disturbance of bats.