The Green Wave: Protecting Migration Corridors in the Bear River Watershed

Utah is famous for having the "Greatest Snow on Earth," but if you’re a mule deer, the real action starts when that snow begins to melt. While we aren’t exactly known as a world-class surfing destination, our local herds spend every spring doing exactly that: surfing the green wave.

Photo credit: Shauna Hart

This isn't just a poetic phrase; it’s a high-stakes survival strategy. As the snow recedes, deer follow the green "wave" of spring growth up the mountains, timing their movement to forage on plants at their most nutritious, "neon-green" stage. By hitting this peak protein at just the right time, deer gain the energy they need to recover from winter and raise the next generation of fawns.

The Geography of the Wave

The Bear River Watershed is a geographic overachiever. While the river meanders through three states, the local mule deer navigate one of the most complex migration corridors in the West defined by three massive mountain ranges: the Uintas, the Wasatch, and the Bear River Range.

By summer, the herds are tucked into high-alpine wilderness, but as the snow flies and the "green wave" recedes, the landscape forces thousands of animals back downward. While we often think of deer habitat as being in the mountains, the lowlands and valley floors are the critical winter destination. Valleys provide winter shelter, but they are also increasingly contested choke points. When already narrow wildlife corridors are blocked by development through dense fencing or new neighborhoods, migration paths can be severed completely.

Photo credit: Utah Division of Wildlife Resources

Working Lands are Wildlife Lands

Success for our local herds often depends on working lands many miles away from summer habitat in the high peaks. New research shows that agricultural and shrubland cover are the single biggest predictors of fawns surviving until adulthood. In fact, healthy agricultural land has a positive impact on deer survival that is twice as large as almost any other factor we can influence.

This is one reason why BRLC works to conserve local farms and ranches. When we help a landowner keep their land in production, we are also protecting the most effective "nursery" a deer herd has.

Photo credit: Shauna Hart

Science Driven Conservation

To ensure we are looking at the most critical parts of these migration routes, we are teaming up with Utah State University (USU) this year to model how deer move through the Bear River watershed.

As we consider projects for conservation, we evaluate them on many factors, including habitat quality and importance to wildlife migration. USU’s study will help us quantify the importance of future projects to local wildlife, helping us understand which specific meadows or fields act as the "gates" to these migration routes.

Protecting the land is a vital first step, but the infrastructure on that land matters too. Even a critical corridor can become a difficult obstacle if it’s blocked by human barriers like standard barbed-wire fences. To assist with this, BRLC is working with willing landowners and partners to install wildlife-friendly fences where appropriate. These designs can include using a smooth bottom wire at a specific height so fawns can crawl safely under, and a top wire which allows adults to clear a jump without snagging their legs, which can be fatal. Other designs include fencing which can be easily lowered to the ground during migration to allow for no-hassle crossings. 

A Legacy for the Next Century

The work BRLC does today, whether saving a ranch in the Bear Lake Valley or a meadow along the Little Bear River, ripples across the entire 7,500-square-mile system.

It takes a healthy watershed to raise a herd. By protecting working lands today, we’re making sure that in 100 years, the "green wave" still rolls and mule deer can still complete their epic journey throughout the Bear River watershed.