Existing comment:
Wildlife Overpasses:
The location of these wildlife overpasses and associated fencing are the result of years of agency collaboration and research that helped identify where desert bighorn sheep are most likely to cross the roadway. Overpasses were recommended because desert bighorn sheep prefer to cross at ridgelines and remain above potential threats. These structures, completed in 2010, marked the first desert bighorn sheep overpasses in the United States.
Desert Bighorn Sheep:
The Black Mountains that surround you may appear inhospitable in both terrain and temperature (summer highs reach 120 degrees F). However, the largest contiguous herd of desert bighorn sheep in the United States lives here. Desert bighorn sheep from this area have been relocated to help restore historical populations throughout Arizona, Colorado, Utah, and Texas.
The above maps show sheep movement data collected along US 93 between mile post 3 and mile post 14 during the highway planning process. Although some sheep did cross the roadway, others viewed it as a barrier. In an effort to enhance habitat connectivity for desert bighorn sheep and improve motorist safety, the data collected provided the necessary information regarding desert bighorn sheep highway crossings and the best locations for three wildlife overpasses at mile posts 3.3, 5.2, and 12.2.
Herd Fragmentation:
Multi-lane roadways create barriers that block animal movements and fragment habitat. The result can be limited access to resources, inbreeding, and the potential to quickly spread disease throughout the herd. |