Mule Deer and Pronghorn Migration: Welfare Across Landscapes Under Pressure

Mule deer and pronghorn antelope undertake some of the longest overland migrations in North America, navigating fences, roads and development. Their welfare depends on maintaining intact migration corridors.

Key Facts

Pronghorn undertake the second-longest land mammal migration in the Western Hemisphere — 160 kilometres in Wyoming
Mule deer migrations in the Greater Yellowstone Ecosystem can exceed 300 kilometres across multiple land ownerships
Barbed wire bottom strands prevent pronghorn from crossing; wildlife-friendly smooth lower strands enable passage
Highway underpasses designed to species preferences achieve crossing rates above 80%
Climate change is altering the timing of green-up that triggers migration, potentially disrupting forage availability

Welfare Considerations

Mule deer and pronghorn migration welfare is fundamentally a landscape connectivity issue. These animals evolved to move across vast distances in response to seasonal forage — barriers cause nutritional stress, reproductive failure and disease vulnerability. Maintaining migration corridors through fence modification, wildlife crossing infrastructure and land use planning is the most direct welfare and conservation intervention available.

What You Can Do

Support Wyoming Migration Initiative and Pronghorn Alliance working on migration corridor protection
Advocate for wildlife-friendly fence design requirements on federal and state land along migration routes
Support highway wildlife crossing infrastructure as a welfare and road safety investment
Learn about migration routes of large ungulates in your region and conservation challenges
Engage with agricultural communities about the value of maintaining migration through their land