September, 1945 



Brown & Yeager: Squirrki.s in Illinois 



465 



Table 8. — Activity in Illinois squirrels based on 716 hours of hunting in which 336 fox 

 squirrels and 218 gray squirrels were observed, June 1— October 31, 1941 and 1942. Hours 

 specified are for Central Standard Time. 



tightly rolled in a ball with leaves pulled 

 over them. In one box there were three 

 such fox squirrels, stacked one on top of 

 another. In numerous cases two squirrels 

 occupied the same box. Every squirrel 

 showing a state of lethargy could be in- 

 duced to leave the nest by shaking the box 

 or by gentle prodding with hand or stick. 

 True hibernation, of course, does not exist 

 in fox or gray squirrels, in Illinois or 

 elsewhere. 



A few occasions permitted activity ob- 

 servations during periods of deep snow. 

 On January 21, 1940, fox squirrels were 

 seen foraging aggressively in a large oak- 

 hickory-elm woodlot in Pike County when 

 snow was 8 inches deep. The observa- 

 tions were made between 2 and 3 o'clock 

 in the afternoon. The day was clear; the 

 air temperature was about 15 degrees F., 

 and the preceding 20 days had been cold 

 and with much snow. Five squirrels and 

 innumerable tracks were seen. There was 

 much evidence of squirrel digging in the 

 snow for nuts and Osage orange fruits; 

 many of the latter had been eaten on 

 stumps and rail fences, and under trees 

 in hedgerows. The senior writer found 

 that deep snow tended to reduce steel trap 

 and box trap catches, particularly on days 

 of long-continued snowstorms. Both spe- 

 cies were observed in mating chases under 

 conditions of light snow or during snow 

 flurries. 



Squirrels apparently are affected by heat 

 as well as by cold. Individuals of both 

 species were observed on hot days lying 

 quietly, legs outstretched and relaxed, on 

 tree branches. One young fox squirrel was 

 collected on August 21, 1942, in the early 

 afternoon, while resting on the second 



highest rail of a fence. Collection was 

 on a very hot, humid day, an hour or so 

 before a rainstorm. This animal seemed 

 to be seeking relief from the oppressive at- 

 mospheric conditions. 



Rain seemed to have some reducing 

 effect on squirrel activity. Neither fox 

 nor gray squirrels were as active during 

 heavy rains or high winds as at most other 

 times, although both species were often 

 seen during showers and immediately after 

 heavy rainfall. Misty days are favored 

 by some hunters, no doubt partly because 

 of the quietness with \/hich squirrels may 

 be stalked at such times. Many fox and 

 gray squirrels were collected by gun on 

 drizzly days, during light showers, and 

 before and after heavy rains. Occasion- 

 ally, animals with wet outer hair were 

 taken, indicating activity either during 

 rain or in wet vegetation. 



Both fox and gray squirrels were ob- 

 served swimming. Two gray squirrels 

 were seen deliberately entering water to 

 reach the opposite shore of a slough, and 

 two fox squirrels were observed swimming 

 to shore after falling from dead, loose- 

 barked soft maple trees. The distance 

 these squirrels were seen swimming was 

 not over 10 yards. 



SEASONAL MOVEMENTS 



Live trapping and general observation 

 offered considerable opportunity for study- 

 ing squirrel movements. The information 

 gathered is given under "Local Move- 

 ments," a subject that involves day-to-day 

 travels of squirrels in feeding and other 

 routine activities; "Migration," which 

 considers mass movements of squirrels in 



