Wildlife Wonders of Alaska - Arctic Ground Squirrels

Arctic ground squirrels are the largest and most northern of the North American ground squirrels. They are established residents of Denali National Park, and this particular fellow entertained us when we traveled along the park road.

These squirrels burrow and establish colonies in areas with well-drained soils, creating a maze of tunnels beneath the surface. They are one of the most important summer food sources for golden eagles, gyrfalcons, foxes, and grizzly bears. Remember the photo I showed last month of the large area that was dug up by a grizzly bear? The bear was undoubtedly in search of a ground squirrel snack! 

Arctic ground squirrels certainly enjoy their summer hiatus after a long winter hibernation of 7 to 8 months. During hibernation, their body temperature drops below freezing, a condition referred to as supercooling. Every two to three weeks, while still sleeping, the squirrels shiver and shake for 12 to 15 hours to create enough heat to warm them back to a normal body temperature of about 98 degrees Fahrenheit. When the shivering and shaking stops, their body temperature drops back to the minimal temperature. Weird, huh?

During the summer, they eat many types of vegetation including the leaves, seeds, fruits, stems, mushrooms, flowers, and roots of many species of grasses, forbs, and woody plants. The squirrels also eat meat from freshly killed animals. As foragers, their goal is to build up fat stores and almost double their body weight by the time they enter hibernation again in fall. Wouldn’t it be great if we could just use winter hibernation as our excuse for consuming a second piece of pie after our Thanksgiving feast?!