Image: Jorn Vangoidtsenhoven


According to the Wyoming Game and Fish Department, the Sublette Pronghorn herd’s migration corridor is at risk. From energy development to road and fence impacts, migrating pronghorn face barrier after barrier on their journey. Thankfully, the agency has recommended beginning the process to formally designate the corridor, which would address these barriers and better protect pronghorn. Currently, we’re midway through the process. Read on to learn more about official designation of the Sublette Pronghorn migration.

As of January 5, 2024, the comment portal has closed — but you and others raised your voice in a big way. Of the roughly 300 comments received by the Wyoming Game and Fish Department, the vast majority — about 90% — spoke in favor of moving forward with the designation process. This was a real landslide and WOC supporters played an important role in tipping the scales. If you submitted a comment, thank you.

The agency used the public input they received to help make the case for proceeding with the designation process at a March 12 meeting of the Wyoming Game and Fish Commission. Happily, the commissioners voted unanimously in favor of moving forward with the next step of the designation process for the Sublette Pronghorn Migration Corridor. Our state’s pronghorn will need your action again — look out for information from us about adding your voice in the coming months.


Official designation of the Sublette Pronghorn migration corridor will provide needed safeguards for this vulnerable herd. The following points break down the specifics.

  • Existing protections are insufficient to mitigate threats. The threat evaluation makes clear that this migration corridor is in jeopardy. From subdivisions, to energy development, to fence and road impacts, the forces that make it harder for Sublette Pronghorn to migrate are pervasive and growing. To ensure the functionality of this migration corridor, official designation is essential.
  • Designation will improve siting for development projects. Designating the Sublette Pronghorn migration corridor opens the door for WGFD to work with industry early in their project planning process to minimize impacts in this seasonally important habitat. This is especially important for newer industries coming to Wyoming from out of state that don’t have established relationships with state wildlife managers.
  • The data is comprehensive. With 20 years of data from over 400 collared pronghorn, the science used to map this corridor is incredibly thorough and provides the direction necessary to protect sensitive habitat.
  • The herd is in need of help. Nearly half of the Sublette Pronghorn herd died last winter due to harsh conditions and a disease outbreak, dropping from an estimated 43,000 pronghorn to 24,000. Animals that were able to migrate further south towards I-80 had much better survival rates, illustrating the necessity of open migratory pathways.
  • Designation will protect a natural wonder of Wyoming. The Sublette herd is among the largest pronghorn populations on earth and undertakes one of the longest remaining terrestrial migrations in existence. The herd’s migration corridor, which includes the renowned ‘Path of the Pronghorn,’ is special — and the state has a responsibility to sustain it into the future.
  • There is broad public support for protections. The people of Wyoming are ardent wildlife supporters and residents enjoy and take pride in our abundant wildlife. The protective management that results from migration corridor designation can improve herd health and increase pronghorn populations, benefitting people across Wyoming.
Image: Jorn Vangoidtsenhoven

Each year, Sublette Pronghorn make an incredible migration from their summer habitat near Grand Teton National Park to their winter range in the Green River Basin — a journey that includes the world-renowned ‘Path of the Pronghorn.’ These animals rely on migration to find food, give birth to their young, and escape the harshness of winter. It’s a grueling journey filled with obstacles. Some pronghorn travel as far as 200 miles and encounter dangerous highway crossings, fences that don’t allow for easy passage, and development, among other challenges.

Formal designation of the Sublette Pronghorn migration corridor would ease the journey for these resilient travelers. Read on to find out how!

Stopping pronghorn in their tracks

Although pronghorn have the ability to jump, they most often duck under fences — if the bottom wire is high enough. If it’s not, pronghorn will travel many miles along fencelines, expending precious energy while they scout for a way through. Designation of the Sublette Pronghorn migration corridor would prioritize conversion of fences to be wildlife-friendly in areas where pronghorn travel, allowing them to continue their journey and conserve energy.

Infestations of invasive weeds

Pronghorn depend on healthy sagebrush habitat, but invasive weeds such as cheatgrass often outcompete native plants. When traveling through rangelands with infestations of invasive species, pronghorn may struggle to find the varied and nutritious forage required to sustain their migration. Formally recognizing this corridor would prioritize ranches where animals travel for funding to maintain healthy habitat and control weeds.

Risky road crossings

In Wyoming, an average of 593 vehicle collisions with pronghorn occur each year. Formally recognizing the corridor could better prioritize roadway management that takes the needs of pronghorn into account, including reduced speed limits and appropriate signage in zones of heavy pronghorn traffic. A win for migrating pronghorn—and for motorists!

Energy development impacts

Migrating pronghorn travel quickly through areas disturbed by the roads and infrastructure associated with oil, gas, and wind energy development. They spend precious energy avoiding development and searching for less disturbed habitat. Formal designation of the corridor would guide development away from the most heavily trafficked and sensitive portions of the migration corridor.

Image: Scott Copeland

The path to migration corridor designation unfolds over three main phases.

Phase 1 centers on a “threat evaluation.” A map for the migration corridor is drafted and WGFD biologists identify existing threats to the migration as well as protections already in place. If biologists judge the existing protections to be insufficient, the agency will recommend moving forward with the designation process.

The public has a chance to weigh in on the draft map and threat evaluation to inform revisions before biologists bring their recommendation before the Wyoming Game and Fish Commission. If the Commission votes to move forward with the designation process, we move on to phase 2.

Phase 2 centers on a “biological risk assessment.” This requires a more thorough analysis by WGFD and is meant to be completed in a year or less. When a draft is complete, biologists will once again seek public input before finalizing the risk assessment and bringing it before the Game and Fish Commission. If the Commission chooses to recommend migration corridor designation to the Governor, we enter the final phase of the designation process.

Phase 3 of the designation process largely depends on the Governor. If they opt to proceed, they will appoint an “Area Working Group” tasked with forming recommendations for corridor designation. This group will include affected county commissions and Tribes as well as representation from conservation, hunting, motorized recreation, agriculture, and industry groups.

Area Working Groups will meet in public and consider the biology, conservation opportunities, and socioeconomic implications of corridor designation before presenting their recommendations to the Governor. Finally, the Governor will formally designate the corridor, return the recommendation to WGFD for further refinement, or reject the designation.

Image: Jorn Vangoidtsenhoven

Submitting your comment in support of corridor designation makes an impact — thank you! If you’re looking for more ways to help, consider making a gift in support of our vital conservation efforts. Our team of conservation professionals is working to support migration corridor designation at every step of the process, and your gift makes a difference.