Saturday, September 13, 2008

Eastern Grey Squirrels

I'm sure that the squirrels at our house in East Berlin, Pa. are no more inventive than other squirrels, but because they perform daily and I have a front row seat, I am constantly amazed at their antics. At one time, long ago, when I thought that I could control the squirrels, we put ears of corn at a distance from the house in an effort to keep them away from the bird feeders - however, they ate their corn and the birdseed too!

A few years ago in an effort to deter the squirrels, we placed our lantern-shaped bird feeder on a post made of smooth PVC pipe. The squirrels couldn't climb up but they could jump down on the feeder from treetops I thought were far enough away to keep the feeder safe. At that point I decided, "if you can't beat them, join them", and have come to realize that there is plenty of feed to go around for birds and squirrels alike.

As the weather grew colder this autumn, the squirrels began a building project in the woods adjacent to our deck, within sight of the bird feeders they frequent. For several days they carried dried leaves and sticks up 20 feet in a nearby tree, fashioning a nest for winter. On bitter cold days when the squirrels are often scarce, we sometimes see one squirrel venture out of the nest to assess the situation before going back in where it is warm and cozy. While squirrels do not hibernate, I have noticed that our squirrels are certainly more active on clear, cold days when there is little or no precipitation. Prime time for activity is early morning and late afternoon, with naps filling their midday.

Squirrel nests are called dreys - there are summer and winter dreys, with those built for summer much simpler in construction. Winter dreys are often lined with bark, bits of moss, fur, feathers or other similar material to make the nest soft and warm. Squirrels have 2 mating seasons and can have a litter in the spring and another in the fall. A litter usually contains 2-3 babies, with each one weighing an ounce and measuring about an inch at birth. Baby squirrels are cared for in the nest until about 10 weeks of age, when they are weaned from their mother's milk.

Tree dens are also often used as a nest by squirrels in this area. These are holes or cavities in the main trunk of hardwood trees which are also lined with soft material as described above. They may use dens in winter months and dreys in summer months.

Most squirrels in our area are Eastern Grey Squirrels. A very similar squirrel prevalent in the Western United States is the Western Grey Squirrel. Both of these squirrels weigh up to 2 pounds and generally live to be 7 or 8 years of age. They have exceptional eyesight and a well-developed sense of smell and hearing. They are grey with white to light grey tails and stomachs.

A cousin to the Eastern and Western Grey Squirrel is the Fox Squirrel, which is about 20% larger - weighing up to 3 pounds and measuring 2 feet in length. This squirrel is grey with a tawny orange color where the Eastern and Western Grey Squirrels are white. The Fox Squirrel is active when the Grey Squirrels are napping. There are also white (albino) squirrels and black (melanistic) grey squirrels..

The squirrel is the fastest rodent, with speeds up to 17 mph. Flying squirrels can make soaring leaps of up to 150 feet, gliding at 5 mph. The flying squirrel flattens out in flight, extending wing-like membranes - loose flaps of skin that stretch from front to hind limbs. North American Flying Squirrels are tiny, weighing only 3 ounces and measuring 10 inches in length. They are nocturnal and said to make good pets!

The average squirrel consumes about 2 pounds of food a week - not only nuts, but fruits, vegetables and grains. They also eat twigs, flower bulbs, mushrooms, and the sweet sap of sugar maple and birch trees. Eastern Grey Squirrels that inhabit our woodlands are classic "scatter hoarders" - they carry nuts in their jaws and bury them in various locations within their home ranges.

Nuts are usually buried in a little cup-shaped hole about 3 inches deep. It is estimated that each grey squirrel buries at least 1,000 nuts every autumn, possibly as many as 10,000 nuts in one season. The squirrel locates its stored nuts by its keen sense of smell, able to locate a nut buried under a foot or more of show. The imperfection of nut-retrieval is why the squirrel is called the "Forest Planter" - many new trees develop!

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