General versus specific surveys: estimating the suitability of different road-crossing structures for small mammals

Published source details D'Amico M., Clevenger A.P., Román J. & Revilla E. (2015) General versus specific surveys: estimating the suitability of different road-crossing structures for small mammals. Journal of Wildlife Management, 79, 854-860.
Share Tweet Email

Actions

This study is summarised as evidence for the following.

	Action	Category
	Install overpasses over roads/railways Action Link
	Install tunnels/culverts/underpass under roads Action Link

Install overpasses over roads/railways

A replicated study in 2009 at two sites along a highway through forest in Alberta, Canada (D'Amico et al. 2015) found that North American deer mice Peromyscus maniculatus, southern red-backed voles Myodes gapperi and meadow voles Microtus pennsylvanicus used overpasses to cross a road. Deer mouse tracks were recorded in 75% of track tubes established on overpasses. Southern red-backed vole tracks were detected in 15% and meadow vole in 5% of track tubes. Over two weeks in September–October 2010, small mammals were surveyed on two 50-m-wide wildlife overpasses above the Trans-Canada Highway. Overpasses consisted of sparse young trees, shrubs and open grassland. Two parallel sample lines, each with five 30 cm long × 10 cm diameter track tubes, with sooted metal sheet as a floor, were placed in the centre of each overpass. Mammals were identified from their footprints.

(Summarised by: Ricardo Rocha)
Install tunnels/culverts/underpass under roads

A study in 2009 at 10 sites along a highway through forest in Alberta, Canada (D'Amico et al. 2015) found that North American deer mice Peromyscus maniculatus used underpasses to cross a road but meadow voles Microtus pennsylvanicus and southern red-backed voles Myodes gapperi did not. Tracks of deer mice were recorded in 90% of track tubes in elliptical culverts, in 87% of track tubes in box culverts and in 75% of track tubes on open-span bridge underpasses. No tracks of meadow vole or southern red-backed vole were detected, despite their use of overpasses in the area. Over two weeks in September–October 2010, small mammals were surveyed in three elliptical metal culverts (4 m high, 7 m wide), five concrete box culverts (2.6 m high, 3.2 m wide) and two open-span bridge underpasses (3 m high, 11 m wide). Underpasses were unvegetated and entrances were characterized by roadside grasslands. Two parallel sample lines, each of five 30 × 10 cm track tubes with sooted metal sheet as a floor, were placed in the centre of each underpass. Mammals were identified from their footprints.

(Summarised by: Ricardo Rocha)