Mule deer crossing the newly completed wildlife overpass. Photo supplied by Nova Simpson
The Wildlife Overpass is a Success
By Larry Hyslop
Mule deer crossing the newly completed wildlife overpass. Photo supplied by Nova Simpson
A study currently in progress shows approximately 3,500 mule deer crossed U.S. 93 using the 10-Mile wildlife overpass and underpasses north of Wells. The study looked at the mule deer migration last fall and this spring as they moved between summer and winter range. Both migrations saw about the same number of deer crossings. The HD Summit overpass was not yet complete and was not part of the study.
Nova Simpson is a UNR graduate student who spent ten weeks in Wells during each migration. Her main research question is whether the overpasses and underpasses are successful. Do they reduce the highway death toll on migrating deer?
She used three techniques to study this question. Each day she searched the overpass area for any deer fatalities and records their location. This spring saw fewer deer fatalities than last fall and she wants to see if this decline continues.
She also placed 12 trail cameras at the openings to the overpass and underpasses. Each camera took a sequence of photos, triggered by approaching deer. After this spring’s migration, she had accumulated 115,000 photos to analyze. She told me just organizing the photos proved to be one of the most difficult parts of her study. Her analysis showed about 700 approaches where the deer turned around without crossing, fewer than she recorded last fall. The overpass proved to be much more popular than the underpasses, with 3,000 of the successful crossings using the overpass.
As a third part of the study, the Nevada Department of Wildlife placed radio collars on 12 mule deer. These showed Nova exactly when and where the deer crossed U.S. 93. NDOW is also using the data from these collars to watch the deer’s movements during the rest of the year. The collars are timed to fall off next summer after her study is complete.
Nova’s study will continue through two more migrations but is already showing results. Mule deer are definitely using the wildlife crossings to safely cross U.S. 93, protecting both deer and highway travelers.
Elko Daily Free Press, “Nature Notes”, 8/26/2011 © Gray Jay Press, Elko, NV
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