The Big Lake pronghorn herd resides in the White Mountains of eastern Arizona within Game Management Unit 1. Mid-March, the Big Lake pronghorn migrate, crossing the Little Colorado River approximately four miles north of River Reservoir, to their high-elevation summer range. The summer range consists primarily of high-elevation grasslands and large alpine meadows near Big Lake. Some individuals continue several miles farther south to summer near Middle Mountain. Fall migration occurs in early to mid-October, when the herd moves north to low-elevation grassland habitats west of Eagar, Arizona. The primary threat to this migration corridor is State Route 260, which experiences high traffic volume and requires crossing for pronghorn to access seasonal ranges. These mapping layers show the location of the winter ranges for pronghorn (Antilocapra americana) in the Big Lake population in Arizona. They were developed from 14 migration sequences collected from a sample size of 8 animals comprising GPS locations collected every 2-4 hours.