The gray squirrel, scientific name Sciurus Carolinensis, is a mammal in the rodent family that has been in North America for over 37 million years. Many factors have contributed to its long life. Its ability to plan for the future is what a squirrel is best known for. Every fall, the gray squirrel spends its day gathering nuts and seeds. Then it hides them so it will have enough food to last through the winter and into the fall. The squirrels hiding pattern is called scatter hoarding. The squirrel will bury its food in hundreds of different locations, that way if another squirrel or animal finding one, the rest will remain. The squirrel cleans each nut or seed before it is hidden, this leaves a scent which the squirrel can find later in the winter. Because of this scent, the squirrel can find its bury food even through a heavy blanket of snow.
Not all nuts or seeds are recovered, since a squirrel will save more food than it really needs. These nuts or seeds then grow into trees and a forest is grown. Squirrels are responsible for planting more trees, than all of mankind.
The nuts have to be opened and cleaned before they are hidden. For this, the squirrel has a very strong jaw structure, combined with a set of twenty two teeth. It can crack open even the hardest nut shell. The squirrels incisors or front teeth are extremely sharp. The grow continuously through out the squirrels life. To keep these teeth sharp and clean, the squirrel will chew off a small branch from a tree. As it bites through the fiber of the branch it will turn its head so the branch will rub against each tooth which cleans the surface. The final process is to sharpen the point of the tooth, this is done in a very similar method. With the squirrel chew on the hardest part of the branch. This cleaning process can take up to an hour at times, and is done everyday. The squirrel does not have the enamel coating on its teeth as humans do. It is very important for them to keep their teeth in perfect condition.
Gray squirrels will mate in the late winter or early spring. This mating ritual willing began with a chase, where several males compete for one female. The males will chase each other through the trees jumping from branch to branch. The female will watch and then choose the male she believes is the strongest. That male will follow her until she is ready to mate. After the copulation, the male will return to its territory, leaving the female to raise the litter. The period of gestation varies between 44 and 46 days for gray squirrels. There are normally four to six born in the litter. The female squirrel will nurse the babies for their first ten weeks. During this time the babies will not leave the nest and are completely dependent on their mother for milk.
At ten to twelve weeks, the baby squirrels will be removed from the nest, and the mother will teach them all the skills they will need to survive on their own. Once these babies leave the nest they are referred to as juveniles. The juvenile squirrels will play together, practice nest building, find and store food. They will also feed in the same area and remain a family unit with their mother, for the next few months.
In the early fall each squirrel will move away to establish its own territory. After twelve months, they will become breeding adults. The mother squirrel will return the live a solitary existence until the next mating season.
The gray squirrel has survived, while other animals have become instinct mainly for its ability to adapt to the changing conditions in the World. Squirrels will move if the food supply is inadequate for their survival. This journey may take them hundreds of miles, before they find a suitable home. Once they have found a source of food and water, they will construct a nest. This is commonly known as a "drey", it is made of twigs and leaves woven together to form a ball about eighteen inches in diameter. The dreys are built in the upper branches of a large tree. These can be easily spotted during the winter months, when the trees are bare. If there are not any large trees in the area, the squirrel will build its nest in an attic or crawl space of a house. This building process goes very quickly and quietly. Most people don't even know a squirrel has move in until much later in the year.
One of the biggest complaints people have about urban squirrels, is the way they raid bird feeders. Since squirrel are opportunists, the sight of a bird feeder full of seeds is just irresistible. They can eat until they're full, and they don't have to touch their food supplies. Getting into these bird feeders can be a challenge, but the squirrel has shown the ability to outsmart these humans that placed those deterrents on that source of food. All this from an animal with a brain the size of a walnut.
Squirrels have very few natural enemies. Hawks and Owls have been able to catch and kill some. While tree snakes have been able to take young squirrels from their nest, but rarely can catch an adult squirrel when it is in a tree. The Bobcat and Fox will try to out run a squirrel on the ground, but again once the squirrel is in a tree the chase is over and it squirrel survives.
The squirrels biggest enemy is Man. Since a squirrel is considered a game animal, it can be killed for its pelt and meat. Also, automobiles kill tens of thousands of squirrels each year. In spite all of this, the squirrel has managed to survive and even flourish through out the World.