Use of passages across a canal by wild mammals and related mortality

  • Published source details Peris S. & Morales J. (2004) Use of passages across a canal by wild mammals and related mortality. European Journal of Wildlife Research, 50, 67-72.


This study is summarised as evidence for the following.

Action Category

Install overpasses over waterways

Action Link
Terrestrial Mammal Conservation
  1. Install overpasses over waterways

    A replicated study in 1993–1998 along a canal in Guardo, northern Spain (Peris & Morales 2004) found that all nine small bridges and six of 14 wider bridges designed for humans and livestock were used as crossing points by mammals. Crossings were made by roe deer Capreolus capreolus (four crossings), red deer Cervus elaphus (four), wild boar Sus scrofa (nine), wolf Canis lupus (three), fox (52) and by mustelids, mainly badgers Meles meles and stone martens Martes foina (14). Iberian hares Lepus granatensis and hedgehogs Erinaceus europaeus were also recorded. Small wildlife bridges were used more than were larger bridges by all mammals as a whole (see paper for details) and bridges near scrubland were used more (12 out of 13 used) than were those near cropland (one out of nine used). Despite crossings being available, 123 roe deer and 34 wild boars were found drowned over the five years. Fourteen concrete bridges (for humans and livestock; 5.0–7.5 m wide) and nine small wildlife bridges (2.5–3.6 m wide) along 24 km of a 5-m-wide concrete water canal were monitored. Tracks in sand and other animal signs were recorded on each bridge every three days from April to September 1998. Drowned mammals were monitored daily from April 1993 to October 1998.

    (Summarised by: Rebecca K. Smith)

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