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Providing evidence to improve practice

Individual study: Are motorway passages worth building? Vertebrate use of road-crossing structures on a Spanish motorway

Published source details

Mata C., Hervàs I., Herranz J., Suàrez F. & Malo J.E. (2008) Are motorway passages worth building? Vertebrate use of road-crossing structures on a Spanish motorway. Journal of Environmental Management, 88, 407-415


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

Install overpasses over roads/railways Terrestrial Mammal Conservation

A replicated study in 2001 in Zamora province, Spain (Mata et al. 2008) found that overpasses were used by mammals. Wildlife overpasses were used by red fox Vulpes vuples (detected on average per overpass on 3.5/10 days), wild boar Sus scofra (2.3/10 days), small mammals (shrews, mice and voles; 0.3/10 days) and rabbits and hares (3.0/10 days). Other overpasses, such as rural tracks, were also used by wild boar (detected on average per crossing on 0.7/10 days), small mammals (1.0/10 days), rabbits and hares (1.8/10 days), red deer Cervus elaphus (0.2/10 days), rats Rattus sp. (1.3/10 days), western hedgehogs Erinaceus europaeus (0.2/10 days), European badger Meles meles (0.2/10 days) and red fox (3.0/10 days). Cat and dog prints were also detected but could not be determined as being from either wild or domestic species. Overall, overpasses (not including wildlife overpasses) were used disproportionately more than were other crossings (which included underpasses and culverts - data presented as indices). Four wildlife overpasses (15–20 m wide, 60–62 m long) and six general overpasses (rural tracks, 7–8 m wide, 58–65 m long) were monitored along the A-52 motorway. The motorway had barrier fencing along its length. Marble dust (1-m-wide cross) was used to record animal tracks daily for 10 days in March–June 2001.

(Summarised by Rebecca K. Smith)

Install barrier fencing and underpasses along roads Terrestrial Mammal Conservation

A study in 2001 along a highway in Zamora province, Spain (Mata et al. 2008; same experimental set-up as Mata et al. 2005) found that road underpasses and culverts, in areas with roadside barrier fencing, were used by mammals. Wildlife underpasses were the most used out of four structure types, by polecats Mustela putorius (detected on average on 0.2/10 days/underpass), roe deer Capreolus capreolus (0.4/10), red deer Cervus elaphus (0.4/10), wild boar Sus scrofa (0.6/10) and rabbits and hares (1.2/10). Open-span underpasses was the most used structure by small-spotted genets Genetta genetta (0.3/10) and red foxes Vulpes vulpes (4.7/10). European badgers Meles meles (3.1/10) and rats (0.4/10) used wildlife-adapted box culverts more than other structure. Small mammals (1.6/10) were most frequently recorded in circular culverts. Thirty-three crossings were monitored. These comprised five wildlife underpasses (14–20 m wide, 5–8 m high, 30–96 m long), seven open-span underpasses (rural tracks/paths, 4–9 m wide, 4–6 m high, 32–72 m long), seven wildlife-adapted box culverts (2–4 m wide, 2–3 m high, 36–45 m long) and 14 circular drainage culverts (2 m diameter, 35–62 m long). The motorway had barrier fencing along its length. Animal tracks were recorded using marble dust (1-m-wide cross) over 10 days in March–June 2001.

(Summarised by Rebecca K. Smith)