Native to Canada and the United States, the Eastern grey squirrel is medium-sized, with no sexual dimorphism in size and color (males and females have about the same size and coloration). The hairs on their body are white, brown, and black, but are tipped with white and give the impression they are grey. It is also not uncommon to see an Eastern grey squirrel that’s entirely black (common in the northern populations of Ontario and Quebec) or entirely white (rarely seen in the southern United States). The color of the fur on their dorsal side ranges from dark grey to pale grey, but also has a lot of red tones, while their chest and stomach are lighter. The fur is thicker in winter and may change with the season.
The bushy tail is one of the most striking things about the Eastern grey squirrel and fulfills several important functions. During the winter season, the squirrel wraps its tail over the body to get protection from cold and rain, while in the summer, it can make it act as a sunshade by pumping more blood into it and allowing its body temperature to decrease. When jumping from high trees, the tail is used as a counterbalance or even as a sort of parachute, slowing the animal’s descend.
Although there are certain similarities between the red squirrel and the grey squirrel, the two differ in:
The Eastern grey squirrels’ diet consists primarily of nuts, buds, shoots, and flowers of oaks, hickory, walnut, pecan, and other deciduous trees. They also love maple, elm, wild cherry, black gum, hazelnut, and gingko tree seeds and fruits; cedar, pine, hemlock, and spruce are also on their menu, along with a wide assortment of fungi and herbaceous plants. Squirrels are, after all, opportunistic feeders, meaning that they’ll feed on anything available. In the summer, they prey on insects, frogs, and birds’ eggs, whose nutrient-rich content is essential for the development of juveniles. When food is scarce, especially in winter, grey squirrels will strip bark from trees to get to the sapwood.
Squirrels either build nests near the top of large trees, especially pine, maple, and oak, (where they are able to find a good nesting site in the forked branches of trees or on limbs) or in dens. The nests are usually located high above the ground and are sustained by a platform of twigs and protected by an outer covering of leaves. The inside is lined with moss, grass, and sometimes bird feathers. Dens are mainly used for overwintering and as brood chambers.
There are two breeding seasons, one in January-February and the second in June-July, each lasting for nearly 3 weeks. If conditions are favorable, squirrels can produce 2 liters per year with 2-4 young each (up to 8). Males fight with each other for the ability to mate with a female; females can mate with one or more males. Pregnancy lasts about 44 days, after which the newborn emerge – naked, having only their vibrissae (whiskers), and weighing no more than 18 g. They are able to leave the nest after 7 weeks and, by the end of the 10th week, are able to feed independently and eat solid food. The young are silver in color and get their adult coat after 3-4 months.
Grey squirrels communicate through a wide range of sounds and positions, also using their strong sense of smell to identify things such as the stress levels and reproductive state of other squirrels. 11 different types of calls have been identified so far, along with scolding noises and tail flicking movements directed at other squirrels or predators.
Squirrels will quickly take up residence inside buildings if there are access points to sheltered areas such as attics and crawlspaces. Gnawing and scratching are the first signs of their presence, as well as cardboard and dried vegetation brought in to build their nest. Here are the main methods used for the elimination and prevention of squirrels inside structures:
Exclusion. You can prevent squirrels from getting inside the house by sealing all access points to attics, chimneys, and other locations inside the house that can make a good nesting site. Make a thorough inspection of the exterior of your house, specifically gaps and places where the wood has rotten or where utility cables enter your building, and seal all entrances with hardware cloth (available at hardware and box stores) and other suitable materials. After all openings are closed, use sheet metal to cover the trunks of nearby trees 6-8 feet above the ground and consider installing customized wire mesh fences to prevent squirrels from entering gardens and orchards.
Habitat modification. To prevent squirrels from getting inside structures via the roof, trim tree branches that can provide easy passage. If squirrels are competing with birds for feed around your bird feeder, provide corn separately for them and grease the pole with oil to discourage them from climbing.
Repellents. Repellents have limited effectiveness; they mainly work by discouraging squirrels from getting inside attics and crawlspaces. Naphthalene can be used in places with low human traffic, and capsaicin or ro-pel can be sprayed on seeds, bulbs, poles, fences, and outdoor furniture. Polybutenes can be placed on poles and the exterior of buildings to prevent squirrels from climbing.
Trapping. Trapping is very effective for eliminating small to medium populations, and there is a variety of trap types (leghold traps, box traps, cage traps, glue traps, etc.) for all squirrel sizes. In some regions, a permit may be required from your local state wildlife agency, since squirrels are considered game species.
At the bird feeder: