Photo Credit: Tes Randle Jolly
SCIENTIFIC NAME: Sciurus niger
DESCRIPTION: Fox squirrels (Sciurus niger) are rodents belonging to the family Sciuridae, and are closely related to mice and rats. The body of an adult fox squirrel is 12-15 inches with the tail adding that much again. It is not unusual for large individuals to weigh close to three pounds, but two and one-half pounds is about average. Fox squirrels are said to be the most variably colored tree squirrels in the world. Their appearance is determined by a mixture of black, silver, and red hairs. In Alabama, the upper parts of their bodies are usually gray but often have a reddish or rust shading. Their bellies are usually reddish or orange, and the tail usually has a distinct reddish cast. Differences among individuals may be great. One characteristic that is relatively constant is the presence of a black facial mask around the eyes and nose. The tips of the nose and ears are most often white. Fox squirrels probably received their common name because of their fox-like lope as they run along the ground as much as their ruddy coloration.
DISTRIBUTION: Fox squirrels are widely distributed in eastern North America. Native populations occur from the Atlantic coast to the great plains, and from the southern tip of Florida to the Great Lakes and the Canadian border. Fox squirrels are found throughout Alabama although populations are often scattered and densities are most often low.
HABITAT: Fox squirrel habitat varies considerably both regionally and locally, including a wide variety of forest types. Throughout western, midwestern, northeastern, and central portions of their range, fox squirrels are most often found in relatively small or narrow stands of mature hardwoods having little understory vegetation and incomplete canopy closure. Fox squirrels living in the Atlantic and Gulf Coastal Plains and southeastern mixed forests are known to inhabit virtually all of the diverse forest habitats in the region, but have been most strongly associated with mature, fire maintained pine forests. In Alabama, fox squirrels are known to inhabit bottomland hardwoods, the shores of bayous, deep cypress swamps, pine / hardwood forests, and upland sandhill habitat dominated by mature pines and numerous scrub oak species. Most fox squirrel sightings in this state are from high dry ridges and areas of residual pine forest, but this may be somewhat misleading. Research done in Alabama and elsewhere in the southeast indicates that while fox squirrels do spend much of their time in mature pine stands, hardwood habitats adjacent to or within these areas tend to be more heavily used than would be expected based on their availability.
FEEDING HABITS: Fox squirrels eat a wide variety of wild foods including acorns, nuts, seeds, fleshy fruits, buds, flowers, twigs, bird eggs, insects, tubers, roots, and fungi. Pine seeds are fed upon heavily during the limited time they are available (late summer), while hard mast is of greatest importance during the fall and winter months. Fox squirrels are, at all times, opportunistic feeders. Primary foods at any given time or location will depend on which provide the most energy and nutrients for the least effort. Most water is obtained by eating succulent vegetation and fruits or by licking dew from leaves. During periods of extreme drought, however, surface water may become necessary for survival. Calcium and other minerals, largely lacking in vegetable foods, are obtained by gnawing bones and antlers or by eating soil.
LIFE HISTORY AND ECOLOGY: In Alabama, litters of 2-5 young fox squirrels are born from late January through March with second litters usually produced in July and August. Gestation is about 44 days. Yearling females breed at about ten months of age and generally skip a breeding period before producing a second litter. Older females in good physical condition will usually breed twice each year when food supplies are good. Almost all summer litters are raised in leaf nests constructed in the branches of trees, as are many winter/spring young in the southern part of the state. Cavities in trees (where available) are used more commonly for brood rearing and shelter during winter in northern parts of Alabama.
Adult fox squirrels tend to be solitary animals. They are rarely found in groups except during breeding chases and in areas providing a concentrated food supply. They are not strictly territorial, but usually avoid or ignore each other. This seems especially true among adult females. When circumstances do bring them together, dominance hierarchies or “pecking orders” are quickly established.
Fox squirrel home ranges overlap broadly, and, especially in the Atlantic and Gulf coastal regions, are often relatively large. Male fox squirrel home ranges are larger than those of females and overlap more broadly with those of other individuals. This is most pronounced during the breeding season when the males range widely in search of mates. Home ranges of females usually overlap relatively little with those of other females. This probably indicates the importance of resource partitioning during brood rearing. Average home ranges in south Alabama have been found to be 68 acres (94 acres for males, 29 acres for females). Many believe that the southern fox squirrel's large body size has resulted from its evolution in the longleaf pine/oak communities once common to this region. Large body size provides fox squirrels with a greater tolerance to food deprivation during times of resource shortage. At the same time it allows for more efficient movement along the ground over long distances in search of necessary resources, and allows more effective handling and utilization of large longleaf pine cones.
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Davis, J.R. 1988. Mammals in Alabama. No. 13. The fox squirrel. Alabama Department of Conservation and Natural Resources, Game and Fish Division. Montgomery, AL. 3 pp.
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Powers, J.S. and N.R. Holler. 1993. Fox squirrel home range and habitat use in the southeastern coastal plain. M.S. Thesis, Auburn Univ., Auburn, AL. 93 pp.
Author: John S. Powers