Bats and their roosting sites are fully protected under UK and European law and it is an offence to kill, injure, capture, or disturb them, or to damage, destroy or obstruct access to their roosts.
Bat surveys generally consist of two stages, which applies to buildings, trees and other structures.
The first stage can be undertaken at any time throughout the year. For building surveys, this involves a site inspection whereby ecologist will gain access into all of the internal voids, attics and basements of the building to search for evidence of bats. The exterior of the building is also assessed for potential roosting sites and access points. Bat surveys of trees are mainly carried out from ground level and low-level ladders with the aid of binoculars, and mainly focus on assessing the potential of the tree to support bats. Occasionally tree surveys will be undertaken using lifting platforms or by specialist licensed climbers so that the tree canopy can be inspected for evidence of bats.
The second stage of the bat survey is seasonally constrained and must be undertaken at a time when bats occupy summer roost sites. For building bat surveys this is from May to August, and from May to September for tree bat surveys. The survey involves positioning observers around the building, tree or structure at dusk and/or dawn to determine if bats are emerging or re-entering the structure and using it as a roost. Ultrasound bat detectors are used during this work to assist with species identification.
If a proposed development will affect a bat roost a European Protected Species Licence may be needed prior to the start of works. The licence application process requires the agreement of a method statement which will ensure that bats can continue to occupy the site after the development has been completed.
Our licensed bat survey specialists are able to undertake all aspects of bat surveys including initial bat scoping surveys, dusk emergence and dawn re-entry flight activity surveys and remote monitoring. We have several years’ experience in the design and implementation of mitigation strategies for bats including the construction of bespoke bat roosts, bat exclusions and bat roost enhancement, as well as applying for European Protected Species licences for bats.
More information about bats and survey techniques can be found in our articles – Bat Droppings, the Bat Year and Architectural Terms for Bat Surveyors, a Guide to Bat Mitigation and Horseshoe Bat Mitigation.
For more information call us on 029 2065 0331.