This winter is far from being the coldest in memory in Southern Michigan, but it is cold enough that I encounter very few other humans during my two to three hour walks in Eliza Howell Park.
The Rouge River is always flowing, but even moving water gradually freezes over at temperatures under 20 degrees F.
On recent walks, I have been looking for signs of how various other animals are managing in the winter. I check on raccoons (curled up in open tree cavities, their backs to the open air) and watch a variety of small birds foraging for food in shrubs, in flower/grass seeds, and on the ground.
Much of my attention, however, has recently been focused on squirrels. Tree squirrels don’t hibernate in winter; rather they rely upon the food that they stored (“squirreled away”) in the fall.
I have been most intently watching Red Squirrels, the smallest of the squirrels in the park.
The American Red Squirrel is a northern species, rarely found south of Pennsylvania and Ohio in the eastern half of the U.S. It frequently inhabits coniferous forests and is well known for hoarding and eating conifer seeds. It is sometimes known as “Pine Squirrel.”
Eliza Howell Park woodland is deciduous, however, and the Red Squirrel’s primary winter food here is Black Walnut. Black Walnut trees are quite common and 2021 was a very productive year. The green-hulled walnuts in trees in summer…
have become the black-hulled walnuts on the ground in the winter.
Red Squirrels store large numbers of nuts for the winter, but this year that does not yet seem to have been needed. There are still many unclaimed nuts on the ground.
Red Squirrels live solitary lives (except for females with young). This winter I have located the tree where one is sheltering. Here it is taking a look out, perhaps watching me, perhaps just keeping an eye on its territory .
This small squirrel, which always seems to be in a hurry, carries a large walnut in its teeth up to a perch to start the process of opening the hard nut.
It quickly shreds the hull, turning the nut constantly with its feet as it removes this layer, letting the small pieces fall.
The hard task of opening the shell takes much longer. This requires cutting with its sharp teeth. Other squirrel species (in EHP, Fox Squirrels and Gray Squirrels) also eat Black Walnuts, but they open them differently. They keep cutting from one side, removing the entire side, until they are able to eat all the nutmeat inside.
The Red Squirrel, on the other hand, opens the nut by making a hole in one side at a time, leaving the dividing rib in place.
I frequently spot the squirrel when I visit the area where it is wintering. And it is often in the process of carrying or eating a walnut. I wonder how many nuts are eaten in a day or a week or a winter. This picture, from a different January, suggests that a squirrel does not move on from a walnut diet quickly.