Individual study: Use of crossings over the Tucson aqueduct by selected mammals
Popowski R.J. & Krausman P.R. (2002) Use of crossings over the Tucson aqueduct by selected mammals. The Southwestern Naturalist, 47, 363-371
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 waterways
A site comparison study in 1996–1997 along an aqueduct in Arizona, USA (Popowski & Krausman 2002) found that overpasses over a waterway within a created wildlife corridor were used by desert mule deer Odocoileus hemionus eremicus, collared peccaries Pecari tajacu and coyotes Canis latrans. Mule deer and peccaries used all six wildlife overpasses inside the corridor. Bridges outside the corridor, not designed for wildlife, were also used. However, there were more mule deer tracks on wildlife overpasses inside the corridor (average 0.06–0.11 tracks/reading) than on bridges outside the corridor (0–0.01 tracks/reading). The same held for peccaries (wildlife overpasses: 0.15–0.21 tracks/reading; bridges: 0.06–0.17). There was no difference for coyotes (wildlife overpasses: (0.28–0.45 tracks/reading; bridges: 0.31–0.59). Aqueduct crossings were provided at five points within and one immediately adjacent to the corridor. Crossings were 9–173 m wide. Four crossings to the north were also monitored along 11 km of aqueduct. Crossings within the corridor contained natural soil and vegetation. Those outside were concrete overchutes or overpasses of water. Animal tracks were recorded on sand plots (2–22/crossing) on ≥7 consecutive days/month from August 1996 to July 1997 (total 117 checks/plot).
(Summarised by Rebecca K. Smith)