There are about ten subspecies of the fox squirrel, which vary in color and location. Fox squirrels are found thoughout Minnesots, except in the northeast portion. The fox squirrel, is also known as the eastern fox squirrel, Bryant's fox squirrel, cat squirrel, Delmarva fox squirrel, and the stump-eared squirrel. Fox squirrels got their name from their gray and red fur coat that resemble that of a gray fox. Also they are larger and have a peculiar way of running along the ground which can give the appearance of a small fox.
The fox squirrel is Minnesota's largest squirrel. Some are so large they may be mistaken for a smaller house cat. Weighing from 1-3 pounds (500 - 1,000 grams). Fox squirrel's length measures 17 - 27 inches (45 to 70 cm). The tail can be 8 - 13 inches (20 to 33 cm). There is no difference in size or appearance of male & female. Will tend to be smaller to the west of the country. Fox squirrels vary in color upper body is brown-grey, orange-gray to dark orange. The top of its ears are lighter in color. Fox squirrels will live in close proximity to grey & black squirrels. Grey squirrels have white underbellies, while fox squirrels have reddish orange colored underbellies. The fox squirrel is unique among mammals in accumulating a chemical in its teeth, bones and tissues which makes its bones pink rather than white. In winter the color is similar to summer color, but the ears may become more tufted and the soles of the feet can become densely furred. They have flexible ankle joints which allow it to rotate its feet by 180 degrees as it descends tree trunks head-first. Yet these squirrels are not as agile as red or gray squirrels. They sometimes fall from trees but rarely get hurt.
Fox Squirrels have sharp claws, developed extensors of digits and flexors of forearms, and abdominal musculature. The fox squirrel has 20 teeth while gray squirrels have 22. Fox squirrels have excellent vision and well-developed senses of hearing and smell. They use scent marking to communicate with other fox squirrels. Fox squirrels also have several sets of vibrissae, thick hairs or whiskers that are used as touch receptors to sense the environment. These are found above and below their eyes, on their chin and nose, and forearms. The tail color is cinnamon mixed with black. The feet are cinnamon.
Tree squirrels, like all rodents, have incisor teeth that continuously grow allowing them to feed on hard nuts and seeds. Special tactile hairs enhance their sense of touch to help them find their way in dark tree holes and cavities.
Fox squirrles have a large vocabulary, consisting of an assortment of clucking and chucking sounds, like some game birds. They will chirp and whistle, especially during the day. They will warn of approaching threats with distress screams. In the spring and fall, groups of fox squirrels clucking and chucking together can make a small ruckus. They also make high-pitched whines during mating. The most common vocalisation is a series of barks, while a chatter bark is given in alarm and the teeth chattering is a sign of aggression.
Fox squirrels are active year-round, for 8 to 14 hours a day. They will spend more of their time on the ground than most other tree squirrels. Often attempting to escape enemies by running rather than climbing. This species is also able to hang by its hind limbs while grasping food in its front feet.
They are not particularly gregarious or playful and have been described as solitary, coming together only in breeding season, although they will share a nest in winter. Ranges of different individuals may overlap, but females with young will defend a small core area of their range. Depending on the season, they construct two types of homes called dreys. Summer dreys are often little more than platforms of sticks high in the branches of trees, while winter dens are usually hollowed out of tree trunks by a succession of occupants over as many as 30 years. Cohabitation of these dens is not uncommon, particularly among breeding pairs.
Nests & Reproduction
Squirrels will mate twice a year but young are usually seen on the cams June - July. The male selects a female, chases her until they mate, and then chooses another. While males may mate with several females, they will vigorously defend these mates against other males. During these breeding periods, each female is receptive for less than one day, and noisy chases take place as dominant males pursue females with which to mate. Male fox squirrels reach sexual maturity at about 10 to 11 months old. Females have been known to give birth as early as eight months old, but most do not breed until the year following their birth.
After breeding, the female seeks a nest, which may be the winter den in a tree cavity or hollow log that she has lined with shredded bark and plant fibers. Tree cavities, usually those formed by woodpeckers, will also be remodeled to winter dens and often serve as nurseries for late winter litters. If an existing den is not available, she will build a tree-top den, which is a 12-19 inch ball shaped nest made of leaves, twigs, and bark. They weave them into warm waterproof shelters, which are at least 30 feet above ground. These nests have small hidden entrances on the sides and will be abandoned after one or two years. Similar leafy platforms are built for summer litters and are often referred to as "cooling beds. Nests are refered to also as dreys. The young are born after 40-44 days, and litter sizes range from 1-7, average is 3. Young squirrels weigh only 1/2 ounce when born, their skin is without fur and pinkish, and their eyes and ears are closed. Development is slow with eyes not opening for 4-5 weeks and ears taking 6 weeks to open. Hair covering starts at about six weeks, and by two months they are getting furry. Fox squirrels are weaned between 12 and 14 weeks but may not be self-supporting until 16 weeks.Young squirrels are prone to chase each other along the ground & around trees. Jump and even roll around together. They tend to be less agile than the adults and will have trouble balancing on the feeders and even fall off!
Fox squirrels thrive best among oak, hickory, walnut, and pine trees, storing the nuts for winter. They will also eat a variety of other food suchs as hazelnuts, fruits & their pits, berries, flowers, maple seeds, mushrooms, sap, fungi, tubers, bulbs, roots, insects & larvae, amphibians, birds and their eggs, and even dead fish. They will gnaw on bones, antlers and turtle shells to obtain calcium and other minerals. As other squirrels they will store nuts in tree nests and burying them in the ground. A single squirrel can bury several thousand nuts over the course of 3 months. In winter and early spring they will eat the buds from trees & brush, young leaves, outer & inner bark and twigs. In the fall crops such as corn, wheat, oats and soybeans.
Tracks, Hunting & Predators
Tracks are normally evenly spaced, and the claw marks are quite visible. The hind feet often strike the ground ahead of or on top of the front footprints, and clusters of tracks can be 10 inches to 5 feet apart depending on the speed of the animal. Fox squirrels were an important source of meat for settlers in the 17th and 18th centuries. They are still hunted over most of their range. They are also sought for trophy and sometimes mounted because of their size or color variations. Minnesota has a strong population of fox squirrels of which about 160,000 are harvested each year.
The life expectancy of a female fox squirrel is about 12 years & 8 years for males. In captivity, fox squirrels have been known to live 18 years. Relatively few natural predators can regularly capture adult fox squirrels. Of these predators, most only take them opportunistically: hawks, coyotes, foxes, weasels, bobcats, great horned owls, red-tailed hawks, red-shouldered hawks, barred owls. Young squirrels in the nest are vulnerable to snakes, raccoons, opossums.