Landscape context matters for attractiveness and effective use of road underpasses by bats

  • Published source details Laforge A., Archaux F., Bas Y., Gouix N., Calatayud F., Latge T. & Barbaro L. (2019) Landscape context matters for attractiveness and effective use of road underpasses by bats. Biological Conservation, 237, 409-422.


This study is summarised as evidence for the following.

Action Category

Install underpasses or culverts as road/railway crossing structures for bats

Action Link
Bat Conservation
  1. Install underpasses or culverts as road/railway crossing structures for bats

    A replicated, site comparison study in 2018 of 24 underpasses along four roads in the Occitanie region, France (Laforge et al 2019) found that underpasses were used by five bat species or species groups in varying proportions, and use was influenced by underpass type and height, road width, and the amount of forest and hedgerows in the surrounding landscape. Myotis, Rhinolophus and Pipistrellus/Miniopterus spp. had greater activity in underpasses that bridged rivers than in culverts with rivers or roads through them (data reported as statistical model results). Taller underpasses were used less (compared to flying over road sections above or adjacent to them) than shorter ones by Rhinolophus spp., and Plecotus spp. were more likely to use underpasses under roads with more lanes (see original paper for details). Greater proportions of bats also used underpasses in landscapes with greater forest cover (Myotis spp. and barbastelle bats Barbastella barbastellus), fewer hedgerows (Myotis spp.) or that were closer to forest patches (Rhinolophus spp.). The 24 underpasses varied in width (2.5–15 m), height (2.5–6 m), length (5–100 m) and type (five river bridges, seven river culverts, 12 road or track culverts). The four roads were surrounded by a mixed landscape of woodland, hedgerows, grassland, and agricultural land. Bat detectors recorded bat activity within, above, and 200 m along the road from, each underpass for three consecutive full nights in July–August 2018.

    (Summarised by: Anna Berthinussen)

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