Squirrels are found in almost any type of environment, from forests and grasslands to cities and suburbs. They're such a familiar part of many surroundings, there's no mistaking the little guys for any other animal. It may surprise you to learn that there are some 279 species of squirrel within three basic types. Two of those types are tree squirrels and ground squirrels. Those two cousins have a number of differences as well as similarities.
Tree and ground squirrels look quite a bit alike at first glance. They're both furry, have bushy tails -- although the ground squirrel's tail isn't quite as bushy -- and boast strong, muscular hind legs. When it comes to coloring, though, the little rodents start to differ. Tree squirrels' fur comes in a range of colors like red, black, gray, white and brown, while most ground squirrels usually sport the same brownish-gray fur dotted with small spots of white or off-white. Tree squirrels' bodies are longer and more lithe than ground squirrels, who have stockier bodies and shorter front legs.
Both types of squirrels thrive on essentially the same diet: fruit, seeds, bark, flowers, shoots and other plants. They're also known to supplement their basic vegetarian diet with bird eggs, insects and even small vertebrates like lizards.
Their very names reveal everything about where the two different types of squirrels make their homes. Although both kinds can and do climb trees, it's the tree squirrel who chooses to live in a high-rise, either carved into a tree or in a nest constructed with leaves, shredded bark and twigs high in tree branches. Ground squirrels, on the other hand, prefer subterranean living, digging out burrows as deep as four feet below the surface. Often, ground squirrels create colonies by connecting the burrows of more than one family.
Other than where they choose to call home, hibernating is another difference in ground and tree squirrels. Tree squirrels stock up on food for the winter because they know it will be hard to find. Ground squirrels sleep the colder days of winter away, though, so they have no need for storing nuts or other food. Both of the little rodents are known for being chatty amongst themselves, with a social system of calling to sound the alarm when there's danger. They also have specific calls between mothers and offspring. Bark stripping is another similarity between the two squirrels. They use it for food, but also tear the bark away from a tree to access the tender wood beneath it.
- University of California Agriculture and Natural Resources: Ground Squirrel
- University of California Agriculture and Natural Resources: Tree Squirrel
- Animal Diversity Web: Squirrels
- Squirrels: The Animal Answer Guide; Richard W. Thorington, Jr. and Katie E. Ferrell
- Squirrels: Furry Scurriers; Rebecca Olien
- Thinkstock/Comstock/Getty Images