About Gray Squirrels

North America has two species of gray squirrel: the western and the eastern, which are closely related and similar in appearance but have different home ranges. The eastern gray squirrel is also found outside the U.S. and is considered an invasive species in the U.K. Having been introduced in the late 19th century, it's pushing Britain's native red squirrel population toward extinction.

  1. Description

    • The two species of gray squirrel look almost identical, having the same coloration: light-gray fur with areas of light brown and black. The eastern gray grows up to 20 inches long and weighs around 26 ounces. The western is slightly larger at 24 inches and up to 33 ounces. The squirrels have long, thick, bushy tails that assist them in balancing, and small feet with sharp claws that help with climbing.

    Range and Habitat

    • The two species share the same type of habitat, and anywhere that has trees makes a suitable home. The eastern gray makes its home range in the eastern U.S., ranging from southern Canada to areas of southeast Texas. The western gray has a smaller range, found mainly in the western states such as Washington, California and parts of Nevada. Both species make their homes in tree holes or in stick-built nests called dreys.

    Diet and Predators

    • The squirrels are mainly vegetarian, feeding on fruits, nuts, seeds and acorns throughout the year. Insects, fungi, tree sap and bark are also included in the diet of both species. Squirrels spend part of the year finding and burying food that they'll dig up in winter. Neither species hibernates, both remaining warm in their nests during bad weather. As small rodents, they're at risk from predators such as snakes, hawks, eagles, bobcats and coyotes.

    Life Cycle

    • For both species of gray squirrel, mating season starts in late winter, with births coming in early spring and again in late summer. Pregnancies last around 43 days, after which 2 to 3 offspring are born completely bald and blind. After 10 weeks, the offspring have grown enough to strike out on their own. Due to various factors such as parasites, predators and hard winters, most squirrels don't live much more than a year. Even so, some individuals have been recorded living up to 10 years in the wild.