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Providing evidence to improve practice

Individual study: Efficacy of road removal for restoring wildlife habitat: Black bear in the Northern Rocky Mountains, USA

Published source details

Switalski T.A. & Nelson C.R. (2011) Efficacy of road removal for restoring wildlife habitat: Black bear in the Northern Rocky Mountains, USA. Biological Conservation, 144, 2666-2673


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

Use signs or access restrictions to reduce disturbance to mammals Terrestrial Mammal Conservation

A replicated, paired sites, site comparison study in 2006–2009 of a forest in Idaho, USA (Switalski & Nelson 2011) found that removing or closing roads increased use of those areas by black bears Ursus americanus. More bears were detected on former roads that had been removed (4.6 detections/100 camera-trap days) than on paired open roads (0.3). Similarly, there were more on closed than on paired open roads when roads were closed by a barrier (closed: 1.5; open: 0.6 detections/100 camera-trap days) or by a gate (closed: 0.5; open: 0 detections/100 camera-trap days). Eighteen closed roads were paired with open roads. Closed roads included seven removed by reprofiling in the previous 10 years, five closed by barriers and six that were gated. Closed roads were sampled by camera-trapping 1.6 km along from their intersection with the paired open road. Open roads were sampled <100 m along from this intersection. One camera trap was used at each site between 1 April and 30 June and again between 30 August and 3 November, annually in 2006–2009.

(Summarised by Nick Littlewood)