Individual study: Use of highway overpass embankments by the woodchuck, Marmota monax
Doucet J.G., Sarrazin J.P.R & Bider J.R. (1974) Use of highway overpass embankments by the woodchuck, Marmota monax. The Canadian Field-Naturalist, 88, 187-190
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
A replicated study in 1971–1973 of 21 highway overpasses constructed for wildlife use in Québec and Ontario, Canada (Doucet et al. 1974) found that they were extensively used by woodchucks Marmota monax. Woodchucks or their burrows were recorded on 18 of 21 overpasses surveyed. Across four surveys on overpasses, minimum total woodchuck numbers were 16–22. On average, underpasses had 45 woodchucks/100 acres, a high figure compared to those reported by other authors in open flat ground. Twenty-one highway overpasses were built up with rubble and sand and covered with topsoil. Four overpasses had an average area of 72,000 square feet. Overpasses were surveyed once in 1971, twice in 1972 and once in 1973. Surveys were conducted in May, when grass (mainly Agropyron repens) was short. Animals and burrows on overpasses were counted from a vehicle (first two surveys) and on foot (last two surveys).
(Summarised by Nick Littlewood)