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Providing evidence to improve practice

Individual study: Clutter-adaptation of bat species predicts their use of under-motorway passageways of contrasting sizes - a natural experiment

Published source details

Abbott I.M., Harrison S. & Butler F. (2012) Clutter-adaptation of bat species predicts their use of under-motorway passageways of contrasting sizes - a natural experiment. Journal of Zoology (London), 287, 124-132


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Install underpasses or culverts as road crossing structures for bats Bat Conservation

A study in 2009 at an underpass below a motorway in an agricultural area of Ennis, west Ireland (Abbott et al. 2012) found that a large underpass was used by five of six bat species although 2–18% of bat passes were recorded over the road above the underpass. Two edge habitat adapted bat species (soprano pipistrelle Pipistrellus pygmaeus, common pipistrelle Pipistrellus pipistrellus) were recorded most frequently in the underpass (soprano pipistrelle: 770 bat passes; common pipistrelle: total 469 bat passes) but 18% of bat passes were recorded over the road above (soprano pipistrelle: 174 bat passes; common pipistrelle: 103 bat passes). The underpass was also used by cluttered habitat adapted brown long-eared bats Plecotus auritus (60 bat passes), lesser horseshoe bats Rhinolophus hipposideros (58 bat passes) and Myotis spp. (30 bat passes), with only a small number of bats recorded over the road above (1–3 bat passes, 2–5%). One open habitat adapted bat species, Leisler’s bat Nyctalus leisleri, was only recorded flying over the road above the underpass (56 bat passes). The motorway had four lanes carrying an average of 11,000 vehicles/day. The underpass (17 m wide x 6 m high x 26 m long) had a minor road through it. Simultaneous recordings were made with bat detectors above and below the underpass for 16 full nights in May 2009.

(Summarised by Anna Berthinussen)