Eastern Sierra Mule Deer Migration Corridor

Round Valley Mule Deer and their Migration Corridor

The Round Valley deer herd consists of approximately 3,000 Rocky Mountain mule deer (Odocoileus hemionus ssp. hemionus) whose winter range is in Round Valley.

The Migration

The Round Valley mule deer herd migrates from its small winter range in Round Valley (northern Inyo County) up through the mid-elevations, and the one mile wide bottleneck in Swall Meadows, to the alpine meadows of the Central Sierra to give birth and to access good forage. The width of the migration corridor in Swall Meadows is limited by the steep cliffs of Wheeler Ridge to the west and the deep canyon of Lower Rock Creek Gorge to the east. Twice a year they traverse their migration corridor where they face mountain lions, cars, and increasing human presence.

Approximately 75% of the herd migrate north in the spring through Swall Meadows, around Wheeler Ridge in southern Mono County, turning west into Long Valley and up into the Mammoth area. Groups of deer will veer off the migration route and travel up canyons into the high Sierra. The other 25% migrate through the Buttermilk area up into the Bishop Creek drainage and over the high passes into the Central Sierra.

Critical Habitat

Viable winter range habitat is critical for a migrating deer herd. In severe winters with heavy snow, the deer must have access to the lowest elevations where forage is still accessible and movement is not hampered by deep snow. The Round Valley deer herd has a relatively small winter range, compared with other mule deer herds throughout the west. Their winter range is only about 30 square miles, while their summer range spreads out to about 1,000 square miles.

Sagebrush (Artemisia tridentata ssp. tridentata) and antelope bitterbrush (Purshia tridentata ssp. tridentata) are the main components of the plant communities that mule deer depend on for food and cover. Antelope bitterbrush, seen in the photo to the left, is a beautiful evergreen shrub in the rose family. Bitterbrush is especially important to deer in the fall when they return from the high elevations. The leaves and shoots provide significant quantities of calcium, phosphorus, fat and crude protein at a critical time of year for the deer. Deer also utilize the meadows, streams and willow thickets that are found in the migration corridor.

Preserving the Migration Corridor

To balance the needs of people and wildlife, ESLT has been working with landowners who want to permanently protect the critical habitat on their land.

With voluntary land protection agreements, known as conservation easements, landowners are providing permanent protection for important lands by restricting subdivision and development, while keeping their land private and under their control.

To date, ESLT has preserved 269 acres in the migration corridor, and is currently working to preserve more.

5 Ways You Can Help Our Local Wildlife

Every landowner, with property large or small, can help maintain the miracle of migration. Butterflies, neotropical songbirds, bats, eagles, and other predators use our local migration corridor. You can act now to ensure permanent safe passage for migrating deer and other wildlife!

1. Maintain native vegetation on your property.

2. Utilize fire-safe practices in your home and landscape.

3. Protect vulnerable wildlife from rambunctious unleashed dogs.

4. Drive cautiously during spring and fall migration.

5. Support open space for wildlife by joining Eastern Sierra Land Trust!

Click to download the Round Valley Mule Deer Herd Brochure here

Thank You to Our Supporters and Partners

California Department of Fish & Wildlife


Bishop Office: 760-872-1171

California Deer Association



Wildlife Conservation Board



Private Landowners in the Migration Corridor

Click here to learn how you can preserve your land.

ESLT Office: 760-873-4554