Squirrels belong to the order “Rodentia.” With 1,650 species, it is the largest group of living mammals. It also comprises 40 percent of all present-day mammal species. There are over 365 species of squirrels in seven families. They include the tree squirrel, ground squirrel, and flying squirrel. Plus, many squirrel-like mammals, such as the gopher, ground hog and prairie dog are in the same family. Squirrels are the most active in late winter when the mating season begins. The males will chase females, as well as chase off other suitors. This ritual of chasing occurs through the trees at top speed, while they perform some of the most breathtaking acrobatics imaginable.
The period of gestation varies from 33 days in the smaller species of pine squirrels, up to 60 days for the larger species such as the common gray and fox squirrels. Squirrels are usually born in the early spring. The average litter consists of four. This varies with climate and location. A second litter can occur in mid summer, if there is an adequate food supply. A female squirrel will choose the strongest male during mating season but is unlikely to breed with that male again. This is nature’s way of reducing inbreeding and preserving the species. A baby squirrel weighs approximately one ounce at birth and is about one-inch long. They do not have hair or teeth, and are virtually blind for the first six to eight weeks.
Gray squirrels come in many colors. Shades of gray are the most common followed by shades of brown. There are also pure white and pure black squirrels, but both are variations of the gray squirrel. The common red squirrel can have an all black coat. While the Kaibab squirrel has a black body with a white tail. Both are found in coniferous forests.
In the summer squirrels are most active two to three hours after sunrise; then they’ll rest in the afternoon, resuming activity again two hours before sunset. The squirrel will retire to its nest well before dark and will rarely leave the nest in the dark. In the winter, the squirrel will complete its activities between dawn and mid- day and will remain in or around the nest until the next day. During winter storms, or severe cold, the squirrel may not leave the nest for days, but the tree squirrel does not hibernate! An adult squirrel normally lives alone but will, in severe cold, share its nest with other squirrels to conserve body heat. Squirrels eyes are located high and on each side of their head. This allows them a wide field of vision, without turning their head. The gray squirrels diet consists of nuts, seeds and fruit. It will eat bird eggs, bugs, and even an animal carcass if there is no other food source available. The gray squirrel requires some salt in its diet and may find this salt in the soil along roads where snow and ice may have been. Squirrels chew on tree branches to sharpen and clean their teeth; that’s why you may see many small branches on the ground around large trees. They will also chew on power lines for the same reason. This has caused many major power outages throughout the country. A squirrel’s brain is about the size of a walnut. The average adult squirrel needs to eat about a pound of food a week to maintain an active life. Squirrels communicate through a series of chirps. The frequency and the duration of the notes communicate everything from laughter to alarm. Their frequency range is normally between .01 KHz. and 10 KHz. (kilohertz). These sounds, when used in conjunction with tail gestures, form the basis for squirrel communication. If a squirrel has taken up residence in your attic or crawl space, the only practical way to remove them is by trapping.
A squirrel will break the shell of a nut with its teeth, and then clean the nut by licking it or rubbing on its face before it is buried. This action applies a scent to the nut, which helps the squirrel find it later, even under a foot of snow. The sweat glands of a tree squirrel are located on their feet, between the feet pads and on their paws between the toes. When hot or excited a squirrel will leave wet tracks on a dry surface. This scent is also used to mark the trees in their territory. If a squirrel’s nest becomes infested with fleas or other parasites, it will move to or build a new nest. This is why there may be more nests than squirrels in a given area. The gray squirrel has been known to build a nest in many unusual places; in an attic or a crawl space seems to be the most common. Squirrels have also built nests in automobiles, chimneys, barbecue grills and under porches. When a squirrel senses danger, its first instinct is to stand motionless. If on the ground it will race to the closest tree or other climbable object to escape. If it is in a tree, it will circle the trunk with its body pressed tightly to the bark. The squirrel’s erratic path while crossing a street is an attempt to confuse the oncoming vehicle… thereby causing it to change direction. This is obliviously the squirrels biggest, and often last, mistake.
The male tree squirrel takes twice as long as the female to groom itself. They are the cleanest animal in the rodent family. A squirrel’s teeth grow continuously. Their incisors will grow six inches per year but stay short due to the constant wear they receive. The most common type of squirrel bite is a result of feeding a squirrel by hand. Never hold the food between your fingers; chances are very good that you will be bitten. A squirrel’s eyes are always looking for predators, and they rarely focus on what they are eating.