||The Mammals of Texas -
Eastern Fox Squirrel
Rodentia : Family Sciuridae : Sciurus
Description. A large tree squirrel with
rusty or reddish underparts and brownish or grayish
upperparts; tail usually less than half of total length,
and cinnamon, mixed with black, in color; feet cinnamon.
External measurements average: total length, 522 mm;
tail, 245 mm; hind foot, 72 mm. Weight, 600-1,300 g.
Distribution in Texas. Occurs in suitable
habitats in eastern two-thirds of state. Introduced some
places outside of native range.
Habits. Fox squirrels are
adaptable to a wide variety of forest habitats, but in
most areas open upland forests of mixed trees support the
heaviest populations. The best habitat is mature
oak-hickory woodland broken into small, irregularly
shaped tracts of 2-8 ha and connected by strips of
woodland which serve as squirrel highways. Intermixture
of pine, elm, beech, pecan, maple, and other
food-producing trees adds to the attractiveness of the
habitat. Along the western parts of their range, fox
squirrels are restricted more or less to river valleys
which support pecans, walnuts, oaks, and other
Where hollow trees are available they
are preferred as den sites and nurseries; if these are
unavailable, the squirrels build outside "leaf"
nests. These are composed of twigs and leaves, usually
cut from the tree in which the nest is placed, and
fashioned into roughly globular structures 30-50 cm in
diameter surrounding an inner cavity 15-20 cm in
A fox squirrel occupies an area of at
least 4 ha in extent in any one season, but during an
entire year 16 or more ha may be utilized. Ranges of
different fox squirrels overlap, and the animals are
somewhat communal in their use of nests and probably also
of winter food stores. A population of one squirrel to 1
ha is about the average carrying capacity of good,
unimproved squirrel habitats.
Acorns are the natural mainstay of fox
squirrels, although they are most important in fall and
winter. Spring and summer foods consist of leftover mast,
insects, green shoots, fruits, and seeds of such trees as
elm and maple. Nuts are eaten from the time they start to
develop and are buried in the fall in individual caches
at the surface of the ground for winter use. The
squirrels can relocate them by smell. Buds of many trees
and fruits of osage orange add to the winter diet.
Mating occurs principally in two
periods January and February and again in May and
June. The former period is most important. Old females
usually breed twice a year and yearlings but once. The
average female produces only four offspring each year.
The gestation period is probably about 6 or 7 weeks, as
in the gray squirrel. At birth the young are blind,
nearly naked, and helpless. They develop rather slowly;
their eyes open in the fifth week. They begin to climb
about over the nest tree at the age of 7 or 8 weeks and
to venture onto the ground at about 10 weeks. At the age
of 3 months they begin to lead a more or less independent
existence. Sexual maturity is reached at the age of 10-11
Fox squirrels are important small game
animals throughout most of their range, hence they are of
decided economic value. Their fondness for green corn,
however, often brings them into conflict with farming
interests, as does their pilfering in nut orchards.