Squirrels live in almost every habitat from tropical rainforest to semiarid desert, avoiding only the high polar regions and the driest of deserts. GEOGRAPHY Squirrels are native to the eastern part of the United States and southeastern Canada, with a range stretching from Quebec south to Florida and west into the eastern third of Texas. Squirrels can be found outside of this range, however, as they have been introduced into Oregon, Washington, California, Montana and British Columbia. Outside of the North America, squirrels were introduced into England, Ireland, Scotland and Italy, where populations thrive.
HABITAT FEATURES Squirrels prefer mature hardwood or mixed deciduous forests of continuous area, though they will also readily inhabit suburban and urban areas. Squirrels have the densest populations in large forested areas with trees that supply them with plenty of diverse and available nut trees, like oak, hickory and walnut. These squirrels most often can be found in tree-filled areas near permanent sources of open freshwater. Though they easily adapt to numerous environments, squirrels do require trees with nesting cavities for reproduction and security, so they are not found in open grasslands or deserts.
Flying Squirrel cruising the hood
ADAPTABILITY Squirrels have been able to adapt to a number of habitats, as their native environments have become more urbanized and forests cleared. Though they require trees for nesting, squirrels will occasionally make use of outside leaf nests, eaves and attics, allowing them to thrive in suburban and urban areas, and areas without heavy forest cover. Because squirrels have a relatively flexible diet (and because acorns--a very common nut in many yards and parks--are a large part of their diet), they are able to further adapt to changing environmental conditions.
Grey Squirrel's crib
ECOLOGICAL ROLE Squirrels provide a source of food for many predatory species within their habitat, including many birds of prey (eagles, hawks, falcons, owls and ospreys), weasels, foxes, coyotes, wolves, bobcats and lynxes. They are also hunted by humans for population control, sport or food throughout much of their range. Squirrels predominantly feed on tree nuts, but will also eat flowers, seeds, fungi, insects and even the occasional bird eggs. In addition to serving as an important prey species, the nut storing tendencies of the squirrel help to disperse tree seeds within their habitat.