Eastern Gray Squirrel Biology
The gray squirrel is numerically the most common squirrel on the East Coast. The gray can weigh up to two pounds in weight in the North and be as long as twenty-one inches. In the South, they would normally be half of that weight. A gray squirrel’s ears are long and pointed. Gray squirrels in the North grow heavy fur on their ears and the bottoms of their feet during winter. A gray squirrel has a pelage or coat made up of two type of hair. The fur is curly, fine and short and used to keep it warm in the cold winter. While the guard hairs are long, white and protect the fur. The long, white guard hair on the tail gives some of them a frosty or silver appearance and the name of silvertail. Their colors are a mixture of black, gray, and light-to-dark brown in a salt and pepper pattern. Their bellies and under legs are white to light gray light in color as is their tail. Individual specimens can be all black, all gray or all white. The gray squirrel will shed its body fur in the spring and fall but they shed their tail hair only in the summer.
Gray squirrels are extremely agile in trees. They have several adaptations for arboreal life. They have parallax vision which is the slight distance that the eyes are separated and allows a squirrel to judge distances when jumping and squirrels can jump eighteen feet with their strong rear legs. Squirrels have color vision but are blue and yellow colorblind. They can see details very well and have the ability to recognize individual squirrels several yards away. The gray squirrel’s toes, which are long and flexible allowing them to cling to vertical surfaces. Some animals can only climb trees that they can get their limbs around but a squirrel can climb any tree no matter how large and when descending, the back legs can rotate one hundred and eighty degrees to allow the sharp, rear claws to hook into the bark. This allows the squirrel to be quite agile and move very rapidly in the trees even going down a tree headfirst.
Gray Squirrels like to make nests in attics, garages, chimneys, barbecue pits, crawl spaces and other unusual places, even in cars. Any place that is dry, safe, and protected that they can squeeze their head through a squirrel can get into and make a nest. Gray squirrels usually have two mating seasons in a year; in mid-winter and early summer. The gestation period is from forty-four to forty-six days. Litter size ranges from two to four pups.
Gray squirrels can live to sixteen years of age. During summer and fall, gray squirrels eat a third more than their body needs to prepare for the rigors of winter. This is in addition to storing food in the ground for future consumption. Like all tree squirrels, gray squirrels do not hibernate but are active throughout the entire year. You may not notice them as much in winter because during severe storms or extreme cold the squirrels may spend more time inside the nest to conserve body heat. But even during severe winter weather they will leave their nests to search for food. Because of their high metabolism (A squirrel’s normal temperature is between 101 to 102 oF), squirrels must eat their weight in food each week to stay active and healthy. The gray squirrel’s diet consists of acorns, animal bones, antlers, berries, bird eggs, bulbs, buds, carrion, certain flowers, frogs, fruit, green shoots, inner bark, insects, mushrooms, nuts, pine seeds, roots, seeds, vegetables and even nestling birds.
Gray squirrels are members of the rodent family. Like all rodents, to keep their teeth sharp they must chew. Homes with gray squirrels often have chewed electrical wires which, if gone unnoticed, can a fire hazard. They mess up the insulation in the walls and ceiling, gnaw holes in walls and allow precipitation to enter the house, etc. They also set up a "litter box" that can produce stains and smells that are unbearable. The most common complaint from homeowners’ stems from the noise in the walls these critters make.