The 150+ mile pronghorn migration through Wyoming’s Sublette region — the longest-protected migration corridor in the lower 48.
- 362 individual animals GPS-collared and tracked
- 688 migration tracks recorded
- Tracking span: 2002–2020
- Average migration distance: ~178 km
- Longest single recorded track: 902 km
- Mapped corridor area: 11,410 km²
The map below shows the herd’s migration corridors and a sample of the GPS tracks behind them. Press play on the slider below the map to animate the migration across the calendar year — watch the tracks pulse with the seasons.
The 150-mile pronghorn migration
The Path of the Pronghorn is the longest documented annual land migration of any mammal in the lower 48 — pronghorn from summer range in Grand Teton National Park travel more than 150 miles south each autumn to winter on the high sagebrush plains of the Upper Green River Basin, in Wyoming’s Sublette County. In April and May they make the return trip, fawning along the way.
Archaeological evidence suggests the migration has been in continuous use for at least 6,000 years — predating the pyramids of Giza and Stonehenge. The pronghorn that walked this route in 4000 BCE used the same bottlenecks the GPS-collared animals use today.
Why fences matter so much
Pronghorn are the only North American ungulates that can’t jump fences. Their anatomy — built for sprinting at 55+ miles per hour across open country — gives them a remarkable top speed but very poor vertical leap. To cross a fence, a pronghorn has to either crawl under it or run around it. Tall, woven-wire sheep fences are nearly impassable, and even four-strand barbed wire causes high entanglement injury rates.
Wyoming Game and Fish, the Bureau of Land Management, and conservation NGOs have built a fence-modification program across the entire Path of the Pronghorn — replacing problem fences with wildlife-friendly designs (smooth bottom wire 16 inches off the ground, top wire 40 inches or less) at thousands of locations.
How to read the animation
Press play below the map. The animation runs through the calendar year — spring migration in March and April, summer on the high meadows, fall migration in October and November, winter in the Upper Green. Watch the tracks pulse south in autumn and north in spring; the rhythm of the corridor is the rhythm of the pronghorn year.
Related migration maps
This page is part of MapScaping’s western big-game migration series. See the Western US Big Game Migration Map for the complete dataset, explore migrations by species, or browse other famous corridors.
- Sublette Mule Deer (Red Desert to Hoback)
- Jackson Elk Herd
- Kaibab Mule Deer
- Ruby Mountains Mule Deer
- Sheldon-Hart Mountain Pronghorn
- Wyoming Range Mule Deer
- Wind River Mule Deer
