As preparation for the development of a proposed reservoir site, Portsmouth Water Ltd. needed a comprehensive survey of an extended area of mixed woodland. Concurrent with two other development sites being surveyed by us in southern England, Bechstein's bats were found to be a consideration. Bechstein's bats are believed to be among the most rare in the UK and are notoriously difficult to detect.
Bat survey work was extended to incorporate extensive capture and radio-tracking of Bechstein's bats over an entire calendar year to enable key roost sites, commuting routes and foraging areas to be identified. Maternity roosts were found to be present at two of the sites surveyed and we have proposed mitigation strategies to minimise the impact of developments on these important roosts. Through these projects, we have extended our detailed understanding of the ecology of this rare species and are well-placed to recommend appropriate mitigation.