Vol. 19, No. 7 
Page 2 
Ecology and Management of Sguirrels C. M. Nixon, 
S. P. Havera 
Fox squirrels comprise about 75 percent of the Illinois squirrel population. 
Fox squirrels are adaptable animals that capitalize on man's manipulation of 
habitat. Unlike gray squirrels, which are creatures of extensive forests, fox 
squirrels frequent small woodlots, sparse open woods, and even hedgerows. One 
reason fox squirrels can exist in such sparsely wooded areas is their ready 
acceptance of cash-grain crops. A wide variety of food may not be as abundant 
in small areas of timber as in large tracts of woodland. However, corn and 
even soybeans can provide a source of nourishment for fox squirrels from late 
summer to early spring, particularly when there is no fall plowing. 
Little is known about the use of soybeans by squirrels. Nutritionally, 
soybeans are high in protein (57 percent), moderate in carbohydrates (33 percent), 
low in fat (1 percent), and fairly high in energy (5>454 cal/g). For comparison, 
the germ of corn kernels that squirrels eat is higher than soybeans in carbo¬ 
hydrates (53 percent) and fat (8 percent) but lower in protein (20 percent) and 
energy (4,443 cal/g). Thus, soybeans are a high-protein food source and a fair 
energy source. 
To obtain data on the use of soybeans by--and their availability to — 
squirrels and other wildlife during the fall and winter, a study area adjacent 
to a stand of mature timber was selected at a Lake Shelbyville Wildlife Manage¬ 
ment Area. Four rows of soybeans next to the timber were left unharvested. 
In October, five plots were established along these four rows. Every 10th 
soybean plant was marked. The numbers of unopened pods on these plants were 
counted and the numbers of pods above the ground and on the ground were noted. 
The soybean plants and pods were counted four times from October 15 to March 
30. The plots were also checked after each snowfall to see what animals were 
using the unharvested soybeans. 
The tracks found in plots showed that deer, quail, and mice made heavy use 
of the soybeans as food. Rabbits and an occasional pheasant were also present; 
they may have been using the soybeans as food or cover, or both. No squirrel 
tracks were seen in the plots. About 80 percent of the soybean pods were 
utilized as food or disappeared during the fall and winter. Of the pods re¬ 
maining in late March, 63 percent were aboveground, and most of them would 
probably have stood above an average snowfall. 
Although no squirrels were observed to use these soybean plots, two 
different instances of squirrel usage of soybeans were noted in early February 
after a brutal January. In Vermilion County, tracks of at least 15 different 
squirrels were seen in a harvested soybean field adjacent to a large tract of 
timber. The squirrels were foraging down each row of soybeans and opening 
pods and eating all but the skins of the soybeans. The ground was covered 
with tracks as far as 40 yards into the field. A few days later in Champaign 
County, in a snow-covered soybean field adjacent to a woods, two fox squirrels 
were seen opening pods that were on stalks protruding above the snow. 
