Assessment of Pronghorn movements and strategies to promote highway permeability : US Highway 89.

PDFTech ReportFHWA-AZ-10-619ECS File No. JPA 07-004TWildlife crossingsOverpassesHighway safetyArizonaArizona. Dept. of TransportationDodd, Norris L.Gagnon, Jeffrey W.Sprague, Scott C.Boe, SusanSchweinsburg, Raymond E.Arizona. Game and Fish Dept. Research BranchArizona. Dept. of TransportationUS Transportation CollectionPronghorn (Antilocapra americana) movements were investigated with Global Position System (GPS)telemetry from 2007 to 2008 along a 28-mile stretch of U.S. Highway 89 in northern Arizona to developstrategies to enhance permeability with future highway reconstruction. Research objectives were to:\ue2\u20ac\ua2 Assess pronghorn movement patterns and distribution and determine highway permeability.\ue2\u20ac\ua2 Investigate the relationships of pronghorn distribution patterns to vehicular traffic volume.\ue2\u20ac\ua2 Assess the influence of fencing on pronghorn highway crossing patterns and permeability.\ue2\u20ac\ua2 Investigate pronghorn-vehicle collision patterns.\ue2\u20ac\ua2 Develop recommendations to enhance pronghorn highway permeability.The team tracked 37 pronghorn (20 females, 17 males) with GPS receiver collars. Of 118,181 GPS fixes,1,125 occurred within 0.15 mile of US 89, and 3,794 occurred within 0.30 mile. Only one pronghorn crossedUS 89 during the two years of tracking. The mean passage rate was a negligible 0.006 crossings/approach.No collisions with vehicles were recorded during the study. In total, 5,035 weighted pronghorn approaches,number of animals/segment, and five other criteria were used to rate 0.6-mile highway segments forsuitability as passage structure locations. The team recommended 3.2-mile spacing between passagestructures and three sites for passage structures integrated with fencing and noise reduction measures