Creature Feature: Squirreled Away
The winter season will soon be upon us here in Michigan! I cannot speak for everyone, but I have noticed several small mammals constantly out and about throughout the day, looking for food to cache for the winter. For this month’s Creature Feature, we will focus on three of the most commonly seen tree squirrels found throughout the Great Lakes State.
Red Squirrel (Tamiasciurus hudsonicus)
Red squirrels are characterized by their reddish-fur, small body size, and territorial behavior. They are spread across much of northern North America and along the Rocky Mountain range, where they dwell in mixed and coniferous forests. Although the average lifespan is about 5 years, red squirrels have a high mortality rate at a young age. This is in large part due to predation from many animals such as birds of prey, or mammals such as foxes and bobcats.
To prepare for winter, a red squirrel stores a hidden supply of food that is accessible during the winter. This hidden cache that they consistently defend is full of cones from trees such as pine and spruce. The distance from a red squirrel den to their food cache is not far; usually within 30 meters of their home. Squirrels do not hibernate, so they base much of their activity on the weather on any given day. It’s kind of similar to many of us humans in a way.
If you take a walk in the woods, and notice a pile of shredded cones beneath a tree, you have just come across a midden! Think of it as discovering a red squirrel’s dining hall; its favorite tree to eat food on.
Eastern Gray Squirrel (Sciurus carolinensis)
It is sometimes difficult to describe the eastern gray squirrel because there is much variation to their appearance. Typically, as their name suggests, the fur is a shade of gray, with other tones blended in. However, with the power of genetics, some individuals may appear all black due to an excess of melanin. These “black squirrels” are not a separate species at all, but are instead a gray squirrel variety. These critters are found throughout eastern North America, east of the Mississippi River, but do not venture as far north as their red squirrel cousins. Other differences include having a potential lifespan exceeding 10 years, and being more active around sunrise and sunset (red squirrels are most active throughout the day).
Within the mixed forests, this squirrel will feast on the buds, seeds, and flowers of dozens of tree species, such as oak and hickory. When winter comes, the gray squirrel will rely on its memory, and its sense of smell to find its hoard, which it had scattered throughout its territory.
Eastern Fox Squirrel (Sciurus niger)
Our last tree squirrel that we will focus on also happens to be the largest in size when compared to the other two. The eastern fox squirrel may look similar to the eastern gray, but also shows off orange on its underside, its face, and its tail. Almost exclusively found within the United States, this species can be found in the east, with a range stretching from from the Great Plains to the Atlantic Coast.
The eastern fox is diurnal - active during the daylight like their red squirrel cousins. However, due to their size, the fox squirrel has fewer predators than what a red squirrel might face. Shelter, whether it is for winter or for a nursery, can be from a tree cavity made by woodpeckers, or it can be a drey - a nest made by woven twigs and leaves. Like the gray, it will scatter its cache to save it for the winter.
The next time you are walking outdoors, be on the lookout for these three critters. No matter where you are, if these squirrels could talk, there is a high likelihood that they’d be saying:
“Winter is Coming”.
An eastern gray, eastern fox, and red squirrel all foraging in the same place.
Click here to learn more about Michigan's tree squirrels
Submitted by naturalist Zach Mork, December 2023