Kitt Peak Wildlife Linkage Crossings

The Kitt Peak Wildlife Linkage lies between milepost 130-138 on State Route 86 (SR 86) on the Tohono O’odham Nation in southwest Arizona. This linkage ranks as one of the 28 “highest priority” linkages of the 152 main wildlife linkages in Arizona due to its habitat value for mule deer, mountain lion, bighorn sheep, Sonoran desert tortoise, and other wildlife species. It serves as a landscape-scale corridor between the Baboquivari Mountains to the south and the Camobabi Mountains to the north.

Between November 2013 and February 2014, two pre-cast concrete arch wildlife underpasses were constructed on SR 86. These underpasses were funded by Pima County’s voter-approved Regional Transportation Authority (RTA) and incorporated into an Arizona Department of Transportation widening project on SR 86. The eastern underpass is 12 feet high, 32 feet wide, and 90 feet in length. The western underpass is 7 feet high, 32 feet wide, and 88 feet in length.

Previously, narrow box culverts served as the only means for wildlife to move under the roadway; these constrained culverts were ineffective for wildlife passage and resulted in many animals trying to cross SR 86 at-grade. The new wildlife underpasses have increased wildlife and motorist safety by reducing wildlife-vehicle collisions.

Four motion-activated wildlife cameras were installed in each of the underpasses in September 2014 to monitor and document wildlife use. 8.5 miles of wildlife fencing linking the wildlife underpasses was installed in early 2015 on both sides of SR 86.

Since the Kitt Peak wildlife underpasses and wildlife fencing were finished, wildlife-vehicle collisions have decreased dramatically. Ongoing challenges include persistent use of the underpasses by free-ranging cattle and feral horses, sedimentation from flooding events, and establishing expectations of use by the U.S. Border Patrol.

To further strengthen and re-connect this wildlife linkage, the Tohono O’odham Nation presented a funding proposal to the RTA in September 2014 for two wildlife bridges in the Kitt Peak Wildlife Linkage. The RTA Board approved $6.6 million for the design and construction of these wildlife bridges on September 25, 2014. The two wildlife bridges will be constructed at mileposts 127.5 and 133.5 in 2017-2018.

Kitt Peak connectivity Map 1114

A pre-cast concrete arch being lowered by crane as part of the underpass construction.

A pre-cast concrete arch being lowered by crane as part of the underpass construction.

The last arch being fixed in place on the Kitt Peak segment. There are 15 total arches.

Looking south, the last arch being fixed in place on the Kitt Peak segment. There are 15 total arches.

The completed underpass with vehicle traffic.

The completed underpass with vehicle traffic.

The camera lock box installed and ready for action.

The camera lock box installed and ready for action.

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Bobcat prints show wildlife are already benefiting from these crossing structures.

A mountain lion about the enter one of the Kitt Peak wildlife underpasses in October 2014. Photo courtesy Tohono O’odham Nation.

Click the links below for video, photos, and picture slideshows (courtesy of Norris Dodd, ADOT Environmental Services, Wildlife Connectivity Coordinator).

ADOT Time Lapse Installation Video

Completed Kitt Peak Wildlife Underpass Installation 2-27-2014

Santa Rosa Pre-Cast Arch Wildlife Underpass Slide Show

SR 86 Santa Rosa Underpass Second Phase

SR 86 Overpass and Wildlife Fencing Proposal

SR 86 Overpass and Wildlife Fencing Power Point Presentation