Provide woody debris in ski run area

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

  • One study evaluated the effects on mammals of providing woody debris in ski run areas. This study was in the USA.



  • Abundance (1 study): A controlled study in the USA found that placing woody debris on ski slopes did not affect overall small mammal abundance and had mixed effects on individual species abundances.


About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A controlled study in 1999–2001 of coniferous forest and adjacent meadow in Colorado, USA (Hadley & Wilson 2004) found that placing woody debris on ski slopes did not affect overall small mammal abundance and had mixed results on individual species. Differences in abundance between treatments were not tested for statistical significance. In the two years following ski run establishment, a similar number of small mammals was caught each year on a ski run with woody debris (76–77 individuals) and a run without (75–83 individuals). Red-backed voles Clethrionomys gapperi were more abundant where woody debris was added (23–43 individuals) than where no woody debris was added (1–23). Similar numbers of heather voles Phenacomys intermedius were caught in both areas (with debris: 10–16; without debris: 10–19) and there were fewer least chipmunk Tamias minimus in areas with woody debris (15–31 individual) than without (42–46 individuals). Ski runs were established in 1999. One run had one or more tree limbs placed end to end in rows across the run, with rows 3–9 m apart. The other did not contain woody debris. Small mammals were live-trapped over four consecutive days on three occasions in July–September 1999–2001.

    Study and other actions tested
Please cite as:

Littlewood, N.A., Rocha, R., Smith, R.K., Martin, P.A., Lockhart, S.L., Schoonover, R.F., Wilman, E., Bladon, A.J., Sainsbury, K.A., Pimm S. and Sutherland, W.J. (2020) Terrestrial Mammal Conservation: Global Evidence for the Effects of Interventions for terrestrial mammals excluding bats and primates. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

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Terrestrial Mammal Conservation

This Action forms part of the Action Synopsis:

Terrestrial Mammal Conservation
Terrestrial Mammal Conservation

Terrestrial Mammal Conservation - Published 2020

Terrestrial Mammal Conservation

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