The Ryegrass mule deer population is part of the larger Sublette herd that winters in the northwest portion of the Green River Basin, west of the Green River and north of Cottonwood Creek (fig. 34). In severe winters, these deer may travel southeast to The Mesa, Ross Ridge, or Reardon Draw areas. The Ryegrass region supports approximately 1,500 to 2,000 deer that migrate northwest to summer ranges in the Wyoming Range and Salt River Range. Many of these deer must traverse U.S. Highway 189, where deer-vehicle collisions are problematic. This stretch of highway is a top priority for underpass installation to improve both wildlife permeability and motorist safety. These data provide the location of migration routes for mule deer (Odocoileus hemionus) in the Ryegrass population in Wyoming. They were developed from Brownian bridge movement models using 133 migration sequences collected from a sample size of 33 animals comprising GPS locations collected every 2-8 hours.