Arizona Pronghorn Anderson Mesa Winter Ranges

Pronghorn in the Anderson Mesa herd reside in Game Management Units 5A and 5B, located southeast of Flagstaff, Arizona. The herd summers at higher elevations (7,326 ft [2,233 m]) on Anderson Mesa and winters at lower elevations (5,577 ft [1,700 m]) in Dog Valley. Summer and winter habitats consist primarily of perennial grasslands and shrubs. The steep mesa, as well as impermeable fencing and pinyon and juniper encroachment, limits pronghorn movement between seasonal ranges. These barriers force the Anderson Mesa herd to follow three distinct migration routes separated by Anderson Canyon, Canyon Diablo, and Jacks Canyon. Approximately 2.50 miles (4.02 km) north of the herd’s winter range, Interstate 40 creates a barrier to any substantial northward movement by the Anderson Mesa pronghorn. In 1967, high snow levels pushed the Anderson Mesa herd to the Interstate 40 boundary (State Route 66 at the time). The herd’s aversion to barriers and limited access to winter forage caused approximately 77 percent of the herd to die that winter. The Anderson Mesa pronghorn herd continues to recover from the large mortality event, which suggests the importance of maintaining migration corridors for the herd’s seasonal movements. These mapping layers show the location of the winter ranges for pronghorn (Antilocapra americana) in the Anderson Mesa population in Arizona. They were developed from 12 sequences collected from a sample size of 10 animals comprising GPS locations collected every 8 hours.

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  "010:12"
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[
  "geospatial"
]