Winter ain’t easy for deer mice. At least, it’s not easy for the ones that don’t invade your cottage, ATV, or shed. In wild, cold, cottage country, food sources are low—which makes deer mice prey for almost every other starving animal around, including small-bodied hunters like shrews and weasels, both slender and speedy enough to chase mice through their underground tunnels.
To prep for winter, a deer mouse hides hundreds of seeds, nuts, and acorns—up to four litres’ worth—in the fall, in empty birds’ nests or tree cavities. When the stash runs out, a mouse will eat anything it can find, including frozen insects or the dormant buds of trees and shrubs.
To stay warm, mice build nests of shredded vegetation or sleep huddled in groups, tucked under rocks, inside the hollows of trees, or in abandoned dens of other small mammals. It’s not as cozy as the insulation in your attic, but they make do. If it gets cold enough—and all that huddling can’t cut it—deer mice are able to lower their body temperature and drop into torpor, a physiologically inactive state that conserves energy.