Snowshoe Hares
Credit: impr2003, iStock
Aptly named because their large hind feet resemble and function like snowshoes, they easily traverse across deep snow during winter, as their toes spread out wide to increase surface area and their densely furred soles help with traction.
They are only found in North America; mostly in remote and dense boreal forests in Canada and Alaska, but also farther south along the Sierras, Rockies, and Appalachian mountain ranges. Snowshoe hares in Canada lost a sizable amount of habitat in this past summer’s wildfires, but still only a small fraction of their total Canadian habitat.
Adults are typically 18–20 inches long and weigh 3–4 pounds (noticeably larger than cottontail rabbits, which are around 2 pounds). And they are one of only a few mammals that change fur coloration seasonally to help camouflage them from predators, going from rusty brown in summer to white in winter.
They are experts at escaping or avoiding predators (such as lynx, coyotes, and foxes). Once their keen hearing and eyesight detects a predator they will often freeze in their tracks, which works well with their nicely camouflaged coats. Or they are highly skilled in running away—able to break into a sprint immediately, run at 35 mph, with bursts up to 50 mph. They can make as many as four bounds in a second (think about that!), zig-zag very quickly, and leap up to 12 feet in a single bound. They are remarkable athletes to see in action. Here’s a brief video of a European cousin even traversing an avalanche!
They reproduce quickly. Females may have up to four litters a year, each time giving birth to up to eight “leverets.” That’s one of the reasons, along with living in fairly remote areas and their key adaptations, that they are currently not considered a threatened species by the International Union for Conservation of Nature.
Beyond all of that, snowshoe hares have been of particular interest to scientists and researchers for two reasons:
They have a very unusual and dramatic population cycle: a “boom and bust” roughly every 10 years, with an abundance of snowshoe hares followed by a significant shortage and then an abundance again. This cycle has gone on with considerable regularity for centuries, as attested in Hudson Bay Company records going back to the 1600s and longstanding Ojibwe oral histories. The remarkable 10-year regularity makes it a standard topic of ecology textbooks, and there’s still some uncertainty about the reasons behind it.
The excellent camouflage provided by the seasonal changing color of their coats is increasingly out of sync with climate change delaying the onset of snow. What once gave them great cover now makes them highly visible to predators. Their rapid reproduction rate will help with variations and more successful adaptations, and there are positive signs that some change is already happening. As National Geographic puts it, snowshoe hares “are in a race between evolution and climate change.”
