The Eastern gray squirrel is a tree squirrel of medium size, and both males and females are of the same size and color. Its fur is mainly black or gray, the gray color being grizzled and often banded with gray and black guard hairs, tinged white, with the underside being white. Its tail is quite bushy and sometimes is reddish in color, and is used for maintaining balance while it leaps between branches. The overall fur color may change with different seasons, with the grayish fur being tawnier during summer, and the tail whiter.
The Eastern gray squirrel is a native animal of the eastern and mid-western parts of America, and to the south of the eastern parts of Canada. It ranges from Manitoba to New Brunswick, and south to Florida and East Texas. It spends most of its time in trees, especially hardwood forests of hickory or oak.
Eastern gray squirrels are aggressive, alert and inquisitive rodents, very fast when moving and jumping amongst the tree tops. These squirrels are a scatter-hoarder; they hoard huge quantities of food for the future and can make several thousand caches per season. They are more active in the daytime than at night, particularly at dawn and during the afternoon. Males and females may share the same nest during the breeding season, which they build in the forks of trees, and during cold winters, squirrels may also share these dreys to stay warm. Females nest alone during pregnancy, and lactating females are particularly aggressive and left alone by other squirrels. These squirrels do not hibernate.
The Eastern gray squirrel eats mostly the nuts, buds and flowers of at least 24 types of oak trees, 10 species of hickory, beech and walnut tree species, pecans, and truffles. Corn, wheat and other crops are eaten, particularly in the winter. In the summer insects are eaten and are probably particularly important for young squirrels.
Eastern gray squirrels have a polygynndrous (promiscuous) mating system. Males compete among themselves for the ability to mate with female eastern grey squirrels. Females may mate with more than one male as well. Breeding occurs in December-February and May-June and is slightly delayed in more northern latitudes. After a gestation period of 40-44 days, the female bears her litter of 1 to 9 (average 2 or 3) in a den or leafy nest. They are cared for in the nest by their mother until they reach independence. Weaning begins in the seventh week and is completed by the tenth. At this point, the juvenile hair is lost. Adult size and mass are reached at 9 months old. Most females begin their reproductive life at 1.25 years but can bear young as early as 5.5 months. Males usually are able to breed at 11 months.
The Eastern gray squirrel is not under any major threat.
The IUCN Red List and other sources don’t provide the number of the Eastern gray squirrel total population size. Currently this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are increasing.
Eastern gray squirrels have an important role in the forest ecosystems where they live. They eat many seeds, and their seed-caching activities are likely to help in dispersing tree seeds. When they eat truffles, they may help distribute truffle fungal spores. They have an effect on the other animals in their ecosystem which they prey upon and are themselves preyed upon. They can cause damage in their native range and are sometimes considered a pest, in that they sometimes build nests in buildings, damaging electrical wiring and woodwork. The squirrels carry the disease parapox virus, which affects native squirrels.