What type of tunnel could reduce road kills?


This study is summarised as evidence for the following.

Action Category

Install culverts or tunnels as road crossings

Action Link
Amphibian Conservation
  1. Install culverts or tunnels as road crossings

    A replicated study in 2001, of two experimental tunnels in Pays de la Loire, France (Lesbarrères, Lodé & Merilä 2004) found that amphibians used tunnels and preferred the soil-lined to the bare tunnel. Tunnels were preferred to bypassing on the grass by common toads Bufo bufo (70%) and edible frogs Rana esculenta (68%). However, agile frogs Rana dalmatina tended to bypass (70%). The soil-lined tunnel was used by 68% of the animals that used the tunnels. The difference between soil-lined and bare tunnels was significant for both frog species but not common toads. Crossing success was higher for all species in the soil-lined tunnel. Two concrete pipes (2 m long, 0.5 m diameter) were placed side by side within an enclosure (5 x 3 m). One was lined with sand and humus, the other left bare. Two 0.5 m lengths of drift-fence were installed at 45° to the entrances. A single animal was placed 1.2 m in front of the tunnels with male calls playing from the far end. Each trial lasted 10 minutes and was repeated four days later. Forty-one common toads, 42 edible frogs and 32 agile frogs captured locally were used.


Output references
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