Seasonal Movement of Elk and Moose
Story by Crys Mooseman / Photos by Marya Moosman
As the final leaves on the valley’s trees fall to the snow-dusted ground, and the autumn tourists leave nothing behind but a quieter roads, we find ourselves in our bi-annual seasonal lull. The melodic tunes of breeding birds are quiet, the bears are no longer seen downtown as they head to their winter dens, and the harvested fields of grain are empty of migrating geese and cranes. I always find this time of year in eastern Idaho to be like a big sigh of relief, a gentle respite before the wave of holiday and winter visitors arrive. But while the Homo sapien populations slow down, the seasonal migration of the regional moose (Alces alces) and elk (Cervus canadensis) populations picks up speed.
As the temperatures drop and the snow begins to blanket the rugged ridges of the local mountain ranges, both elk and moose respond by embarking on seasonal movements to valley floors. This journey, driven by survival and guided by instinct, showcases the resilience and adaptability of these beautiful animals. The region’s diverse geography, from its steep mountain ranges to its river valleys and forested slopes, plays a vital role in shaping this migration. Through this journey, elk and moose reveal the ways they have evolved to thrive in the intermountain west’s challenging winter environment.
Elk and moose migrate primarily to avoid deep snow and to find reliable food sources. As winter approaches, the vegetation at higher altitudes diminishes, and snow accumulation makes it difficult for these animals to access the ground vegetation they rely on. Additionally, the energy required to travel through deep snow can drain their energy reserves. By moving to lower elevations, where snow is lighter and vegetation more accessible, elk and moose can sustain themselves through the lean winter months.
While elk and moose share similar migration drivers, their dietary needs and migration patterns differ slightly. These distinct needs influence the migration patterns and the specific habitats they seek out as they descend from their summer ranges.
In late fall, our region’s elk herds begin to move from high mountain ranges to lower valleys and forested areas. The timing of this movement varies depending on local weather conditions and the depth of snow at higher altitudes. Elk have strong site fidelity, often returning to the same wintering grounds year after year. These areas, typically located in fields and lower-altitude forests, provide sheltered landscapes with ample forage such as grasses, shrubs, and small plants that remain accessible even with moderate snowfall.
One of the most spectacular aspects of elk migration is the sheer size of the herds. Family groups combine into larger herds as they migrate down from the mountains, sometimes numbering in the hundreds. Herd dynamics help elk fend off predators like wolves, who may follow herds to take advantage of prey concentrated in lower areas. The herds also display remarkable coordination, moving together through forests, across rivers, and over open landscapes to reach their wintering valleys. Once they arrive, they’ll spend the winter conserving energy, foraging on the remaining vegetation, and staying alert for predators.
Unlike elk, moose are more solitary and undertake shorter migrations. They generally remain in wooded areas with thick cover, moving down from high-altitude summer habitats to mid-elevation forests and riparian zones. Moose have long legs that allow them to navigate deep snow more easily than elk, but they still descend to avoid the harshest winter conditions.
During the winter, moose rely on a diet of woody browse, such as willow, aspen, and other deciduous trees that grow along rivers and in protected canyons. Their browsing habits mean that moose prefer wintering areas near water sources, where dense vegetation remains accessible and where they are better protected from the elements. These areas not only provide a food source but also the thermal cover moose need to survive frigid temperatures.
In areas near communities, moose sometimes venture close to human settlements in search of food, which can lead to conflict as they forage on ornamental trees and shrubs. Residents often spot moose near our towns and roadways during especially harsh winters, highlighting the adaptability of these animals even in human-altered landscapes.
Both elk and moose face unique challenges during winter migration. In recent years, the region’s growing population and increased development have disrupted some of these traditional migratory corridors, making the journey more difficult. Roads, fences, and housing developments fragment the landscapes these animals rely on, posing risks such as vehicle collisions and habitat loss. However, local efforts to protect migration corridors and critical wintering grounds are helping to maintain these seasonal movements. State agencies and conservation groups such as Teton Regional Land Trust work to preserve key habitats, ensuring elk and moose can continue to migrate as they have for generations.
The winter migration of elk and moose is a reminder of Idaho’s wild beauty and the intricate ways animals adapt to seasonal changes. Watching elk herds move as one or spotting a lone moose along the frosty rivers reflects the delicate balance between survival, instinct, and landscape. The Greater Yellowstone region’s rich biodiversity and the interconnectedness of its ecosystems are on full display during these migrations, illustrating the resilience of wildlife in a challenging environment. So as winter settles in and you “migrate” into your seasonal behaviors that help you through the long winters, make a trip out to the river, or the foothills to see the elk and moose doing the same, and take a moment to appreciate their beauty and strength, and embrace it for yourself as the first snow storms blanket our shared home.
