496 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 5 



200,000 or more squirrels are resident in 

 municipal areas in the state. 



Stripmines, which provide an unimpor- 

 tant habitat in the state, are best repre- 

 sented in Vermilion, Perry, Saline and 

 Fulton counties (Yeager 1942), fig. 20. 

 Only in Vermilion County has forest suc- 

 cession in this type of habitat advanced 

 far enough to attract gray squirrels. The 

 cover usually found in stripmine areas is 

 an early stage of river-bottom forest, 

 consisting mainly of Cottonwood, syca- 

 more, willows, elms and maples, a com- 

 bination low in quality as all-year range. 

 Buds, flowers and seeds of trees, and fruits 

 of brambles and wild strawberries offer 

 an appreciable amount of spring and 

 summer forage. Hickory nuts and acorns 

 are seldom represented in these stands. 

 Probably not more than a few hundred 

 squirrels, most of which are fox squirrels, 

 are resident on Illinois stripped lands. 



FOODS AND FEEDING 



In this investigation no study of squir- 

 rel foods based on detailed laboratory anal- 

 ysis of stomach contents was attempted. 

 Through 2 years of field work, however, 



every opportunity to observe and record 

 squirrel feeding was utilized. Many as- 

 pects of the study — particularly those as- 

 sociated with collecting specimens, trap- 

 ping live animals and making inspections 

 of den boxes — were well adapted to the 

 making of reliable observations. In 716 

 hours devoted to hunting, several hundred 

 records on squirrel feeding were gathered. 

 Although the nature of the data precludes 

 quantitative evaluation, the writers be- 

 lieve that a good general picture of feed- 

 ing, based on frequency of observation, was 

 obtained. 



In the following discussion, as well as in 

 table 22, no food is listed unless squirrels 

 were observed eating it, or unless other 

 positive evidence of its having been eaten 

 was obtained. Food remains of squirrels 

 were easily distinguished from those of 

 other rodents by the location of "cuttings" 

 as well as by incisor marks on them 

 (Pearce 1938). Only fresh material was 

 used in these determinations. It was im- 

 practical to distinguish between fox and 

 gray squirrel food remains, and for this 

 reason, as well as because of great similar- 

 ity in food habitats, this section of our re- 

 port is, in general, applicable to both spe- 



Fig. 20. — Stripmines, lacking in trees bearing acorns and nuts, are poor year around squir- 

 rel habitats. Vermilion County. 



