Mule deer make the longest big-game migrations in the lower 48 — including the 150-mile Sublette herd journey through Wyoming’s Red Desert and Hoback Basin, the most famous land migration in North America. This map shows every USGS-mapped mule deer migration corridor across the western United States — 110 herd units, 2,941 individually GPS-collared animals, and 9,255 tracked migration segments, recorded between 1999 and 2024.

Click any shape to see herd-level statistics. Filter by state to focus on the herds local to you, or pick a featured corridor at the bottom of the page to load that herd’s GPS tracks onto the map.

The mule deer migration in numbers

The numbers behind this map come from a multi-decade effort by the USGS Corridor Mapping Team and state wildlife agencies across ten western states. For mule deer, that effort has produced:

• 2,941 individual mule deer tracked by GPS collar, often for multiple years each
• 9,255 migration tracks recorded between 1999 and 2024
• 110 distinct herd units mapped across ten states
• 194,506 km² of corridor identified from the GPS data

About mule deer migrations

Mule deer (Odocoileus hemionus) are the headline species of western big-game migrations. They winter in lower-elevation sagebrush and pinyon-juniper country, then climb to high-elevation aspen and conifer forests for the summer — sometimes covering more than 150 miles each way. The journey takes weeks, with multiple stopovers where animals refuel on emerging spring greenery before pushing higher.

Mule deer migrations are learned behaviour. Fawns walk the route with their mothers and inherit the same corridor, stopover sites, and timing. If a generation of deer loses access to a corridor, the migration knowledge can disappear with them.

Despite robust tracking, mule deer populations have declined across much of the West since the 1990s. Researchers cite habitat loss, severe winters, predation pressure on fawns, and energy development across winter range as primary drivers. Conservation focus has shifted from harvest management toward protecting the specific corridors and stopovers shown on this map.

Mule Deer herds by state

This dataset contains tracked herd units in the following states. Click a state to see every herd mapped within it.

• Wyoming — 28 mule deer herd units
• California — 21 mule deer herd units
• Oregon — 20 mule deer herd units
• Utah — 13 mule deer herd units
• Nevada — 11 mule deer herd units
• New Mexico — 7 mule deer herd units
• Colorado — 5 mule deer herd units
• Arizona — 4 mule deer herd units
• Washington — 4 mule deer herd units

Famous mule deer migrations

A handful of mule deer migrations are particularly well-known — for their length, their conservation history, or their cultural significance. Each has a dedicated page with full GPS track animation.

Sublette Mule Deer (Red Desert to Hoback)

The most famous big-game migration in North America — mule deer travelling 150+ miles between summer range in the Wyoming Range and winter range in the Red Desert. 253 animals tracked.

Kaibab Mule Deer

The historic North Rim of the Grand Canyon herd — subject of Aldo Leopold’s landmark conservation writings. 48 animals tracked.

Ruby Mountains Mule Deer

High alpine to sagebrush migrations across the Ruby Mountains of northeast Nevada — one of the most dramatic elevation changes in any Western migration. 117 animals tracked.

Wyoming Range Mule Deer

Long-distance mule deer migrations through the Wyoming Range — Hoback Basin to Pinedale country, recently in decline due to severe winters. 126 animals tracked.

Wind River Mule Deer

Mule deer crossing the Wind River Range — among the longest-tracked migrations in the Greater Yellowstone Ecosystem. 84 animals tracked.

Explore the full picture

This page is part of MapScaping’s western big-game migration series. See the Western US Big Game Migration Map for the complete dataset, or browse migrations by other species: Elk, Pronghorn, Moose, White-tailed Deer .