Winter is here in Eagle County! Nights are long, temperatures are low, and the mountainous landscape is covered in snow. During these chilly months, how do plants and animals endure the harsh winter conditions, and what happens to them when the snow falls? The white blanket that covers the ground (known as the snowpack) is crucial to the survival of plants and animals in a cold mountain ecosystem.
Snowpack: The Lifeblood of Winter Ecosystems
Each snowflake Eagle County receives contributes to the snowpack, and this accumulation of snow remains on the ground throughout the winter season. More than just a fun surface to slide down on skis and snowboards, the snowpack plays a critical role in maintaining local water supplies and supporting plant and animal life. The depth and density of the snow insulates the ground beneath, protecting plants and their roots from extreme cold. At the same time, it creates habitat for animals, offering protection from predators and harsh temperatures, as well as access to food.
Plant Adaptations for Winter
Winter can be a harsh time for plants, especially in cold environments where freezing temperatures, reduced light, and snow cover are the norm. One of the key adaptations plants in Eagle County use to survive the winter is dormancy. Plants are able to slow down their activity and put growth on pause until more favorable growing conditions return in the spring and summer. Colorado perennial plants like the Columbine and Lupine, that come back year-after-year, survive underground insulated by snow and soil. These plants can prevent ice crystals from forming inside their cells by accumulating natural “anti-freeze” compounds, which lowers the freezing point of their cell fluid. Evergreen trees that keep their leaves and stay green year-round, like Spruce, Fir, and Juniper are also champions of the cold. They have specialized needle-like leaves that are coated with a waxy layer to prevent freezing and water loss. In contrast, aspen trees, which shed their leaves in the fall, rely on different strategies for winter survival. Aspen’s smooth, white bark plays a significant role in preserving the insulative snowpack by reflecting sunlight and reducing snowmelt around the tree’s base. This strategy benefits not just the aspen, but also other plants and animals that rely on the snowpack for survival.
Animal Adaptations for Winter
When it comes to animals surviving the winter, their success lies in changes in their bodies and behaviors. Like plants, many animals enter a state of dormancy. Trout slow their metabolisms and seek deeper, warmer waters. Bears enter a lighter form of hibernation known as torpor, while true hibernators like ground squirrels drop their body temperatures to near freezing and survive for months without eating. Animals like deer, elk, and moose grow thicker coats to insulate themselves against the cold and move to lower elevations where food is more accessible. Other highly adapted animals like the ptarmigan, ermine, and snowshoe hare change from brown to white during the snowy months to blend in with their surroundings. And what about human animals? Just like animals and plants, humans adapt to the winter by bundling up in warm layers, finding shelter from the cold, and embracing the snowpack with a variety of fun winter activities!
Life in the Cold at Walking Mountains
This time of year, Walking Mountains staff are gearing up for a busy winter season packed with programming designed to engage both residents and visitors of Eagle County. Every December during winter staff training, the Community Programs and Youth Programs Teams come together to explore how cold weather shapes local ecosystems during their annual Life in the Cold Day. Community Programs Manager, Scott Dunn, sums it up well, “There are two questions I frequently ask myself… What is life? And why am I cold? Thank God for Life in the Cold Day. This annual tradition provides a brief glimpse of clarity as both of those questions are explored.” The profound impacts of winter on plants, animals, and people alike is a beautiful reminder that while winter may be cold and challenging, it is also a time of resilience and adaptation in Eagle County's beloved mountain ecosystem.
Sarah Noyes is a Foley Graduate Fellow at Walking Mountains. Sarah enjoys skiing, swimming, hiking, biking, painting, being on boats, and making soup.