EASTERN GRAY SQUIRREL

The 'Eastern Gray Squirrel' (''Sciurus carolinensis'') is a tree squirrel that is native to the Eastern and Midwestern United States, as well as the eastern provinces of Canada. The species name ''carolinensis'' refers to the Carolinas, where they were first recorded by zoologists and are still extremely common. The native range of the Eastern Gray Squirrel overlaps with that of the Fox Squirrel (''Sciurus niger''), with which it is sometimes confused.
A prolific and adaptable species, it has been introduced, to and thrives, in several regions of the Western United States. The Eastern Gray Squirrel has also been introduced to the United Kingdom where it has successfully spread across the country and displaced the native Red Squirrel (''Sciurus vulgaris''). There are concerns the same will happen in Italy.

Contents

Description

Behavior

Distribution

Introductions

Displacement of red squirrels

References

See also

External links

Description

As its name suggests, the Eastern Gray Squirrel's fur is predominantly gray, but it can have a reddish tinge. Its belly is white and it has a large bushy tail. Particularly in urban situations where predation risk is reduced, both albino and melanistic forms of the Eastern Gray Squirrel are quite often found. The melanistic form, which is nearly black all over, is predominant in certain local populations as well as in large parts of southeastern Canada.

Behavior

Like many members of the family Sciuridae, the Eastern Gray Squirrel is a scatter-hoarder; that is, it hoards food in numerous small caches for recovery later. Some of these caches (especially those made near the site of a sudden abundance of food) are retrieved within hours or days for re-burial in a more secure site. Others are not retrieved until months later. It has been estimated that each squirrel makes several thousand caches each season. The squirrels have very accurate spatial memory for the locations of these caches, and use distant and nearby landmarks to retrieve them. Olfaction is used only once the squirrel is within close range (a few centimeters at most) of the cache site.
The Eastern Gray Squirrel makes a variety of noises, including a loud screeching, a "buck buck buck" sound and a chattering, often followed by "kyukyukyuuuu". They make these noises to communicate with other gray squirrels, and sometimes they make noises during mating.


These squirrels build a type of nest, known as a drey, in the forks of trees. These consist mainly of dry leaves and twigs. Sometimes they will also attempt to build a nest in the attic or exterior walls of houses, often to the great annoyance and frustration of the homeowner. They also invade bird feeders for millet and sunflower seeds, but safflower is often used instead, as they seem to have no taste for it. Some seed is sold with hot pepper coating, because only mammals such as squirrels can taste its capsaicin, while the birds cannot. Mixing hot pepper flakes into regular birdseed works well as a squirrel deterrent. They have also been known to dig up bulbs from gardens. Their reputation for these habits has led some to call them "tree rats" or "rats with fuzzy tails".
Predators include hawks, mustelids, skunks, raccoons, domestic cats,snakes and owls. On occasion, this squirrel may lose part of its tail while escaping a predator.

Distribution

The Eastern Gray Squirrel is common throughout most of its natural range and wherever it has been introduced. It readily becomes tolerant of humans and learns to take food left or offered by picnickers.

Introductions

The Eastern Gray has been introduced at a variety of locations on the west coast of North America, including the states of Washington and Oregon, San Francisco and the Peninsula area of San Mateo and Santa Clara counties south of the city. It is now the most common squirrel in many urban and suburban habitats in the Western United States north of Central California. At the turn of the 20th century the Eastern Gray Squirrel was introduced into South Africa and England, spreading across the latter and then invading both Wales and parts of southern Scotland where it has almost exclusively displaced the population of the native Red Squirrel. It has also been introduced to Italy, and the European Union is concerned that the Eastern Gray Squirrel will displace the Red Squirrel from parts of the European continent as well.

Displacement of red squirrels

In the United Kingdom, the animal is known simply as the 'grey squirrel' and has no natural predators. This has added to their rapid population growth and has led to the species being classed as a pest. Measures are being devised to reduce their numbers, including one plan for famous television chefs to promote the idea of eating gray squirrels.^[1] In areas where isolated populations of Red Squirrels survive, such as the island of Anglesey, eradication programmes for gray squirrels are in progress to allow red squirrel populations to recover.^[2]
Although the matter is controversial and complex, the main factor in the displacement of Red Squirrels by gray squirrels is thought to be competition for resources, leading to a decrease in fitness of the red squirrels on all measures.^[3] Gray squirrels tend to be larger and stronger than Red Squirrels and have been shown to have a greater ability to put on fat before the winter. These factors are thought to result in gray squirrels competing effectively for a larger share of the available food, resulting in lower survival and breeding rates in Red Squirrels. Parapoxvirus may also be a strongly contributing factor. Red Squirrels are fatally affected by this disease, while gray squirrels are unaffected but thought to be carriers. Red Squirrels are also more affected by habitat destruction and fragmentation than the more adaptable gray squirrel, which has also contributed to a decrease in their numbers and a linked increase in the numbers of gray squirrels.
This has also been the case in the Pacific region of North America, where the native Red Squirrels have been largely displaced by gray squirrels in parks and forests throughout the region.

References

1. Jamie 'must back squirrel-eating'
2. Red squirrel conservation, squirrel ecology and grey squirrel management
3. Wauters, L. A., Gurnell, J., Martinoli, A., & Tosi, G. (2002). Interspecific competition between native eurasian red squirrels and alien gray squirrels: does resource partitioning occur? ''Behavioral Ecology and Sociobiology, 52'', 332-341.

See also

★ Fox Squirrel

★ Western Gray Squirrel

External links

★ Eastern Gray Squirrel Facts from the NatureMapping Program

★ FCBS Directoy: Eastern Gray Squirrel

★ A brief history of the black squirrel at Kent State University

★ Eastern Gray Squirrel Facts from Hinterland Who's Who

★ An Exotic Evolution: Black Squirrels Imported in Early 1900s Gain Foothold (from ''The Washington Post'')