Individual study: Bats and mines: evaluating Townsend’s big-eared bat (Corynorhinus townsendii) maternity colony behavioral response to gating
Diamond G.F. & Diamond J.M. (2014) Bats and mines: evaluating Townsend’s big-eared bat (Corynorhinus townsendii) maternity colony behavioral response to gating. Western North American Naturalist, 74, 416-426
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Install and maintain gates at mine entrances to restrict public access
A replicated, controlled, before-and-after study in 2003–2004 at four abandoned mines in western Utah, USA (Diamond & Diamond 2014) found that gated mines had more Townsend’s big-eared bats Corynorhinus townsendii circling at entrances than entering or exiting them, and 2–7% of bats flying through the entrances collided with the gates. More Townsend’s big-eared bats circled at gated mine entrances than flew through them (data not reported). However, there was no difference in the number of bats circling and entering/exiting at ungated mines. Bats were observed colliding with gates at all four gated mines (2–7 % of bats entering or exiting/night, total <5–50 bats/gate). All of four mines had maternity colonies of Townsend’s big-eared bats (average 84–112 bats). Two mines were gated before the study in 1998 and 2000 and two had gates installed during the study in 2004. All gate designs were ‘bat-compatible’ (round steel bars with horizontal bars spaced 10–14 cm apart). Each of the four mines was surveyed with infrared video cameras at the entrances during two consecutive mornings and a single night each month in May–July 2003 (before gating) and in May and July–September 2004 (after gating).
(Summarised by Anna Berthinussen)