September, 1945 



Brown & Yeager: Squirrels in Illinois 



527 



Table 27. — Calculated loss in unborn and suckling young per 100 squirrels bagged in Illinois, 

 July 16-October 31, inclusive, 1940-1943. A kill ratio of approximately 70 fox squirrels to 30 

 gray squirrels was obtained from Illinois kill figures, table 3. 



Types of Loss bv Species 



Mature, potentially breeding, females (tabic 15j 



Fox squirrels, 21 of 115 animals (tables 14 and 15; 18.3% of 70 animaisj 

 Gray squirrels, 16 of 62 animals (25.8% of 30 animals) 



Pregnant (table 15) 



Fox squirrels, 6 of 21 mature females (28.6% of 12.8 mature females) .... 

 Gray squirrels, 6 of 16 mature females (37.5% of 7.7 mature females) . . . 



Lactating (table 15) 



Fox squirrels, 6 of 21 mature females (28.6% of 12.8 mature females). . 

 Gray squirrels, 5 of 16 mature females (31.3% of 7.7 mature females). . 



Unborn young* 



P'ox squirrels (3.7 x 2.57) 9.5 



Gray squirrels (2.9 x 2.43) 7.0 



Total unborn young 



Number Per 100 



Squirrels (70 



Fox Squirrels, 



30 Gray 



Squirrels) 



12 8 



7,7 



3.7 

 2.9 



3.7 

 2.4 



16.5 



Suckling young* 



Fox squirrels (3.7 x 2.57) 9.5 



Gray squirrels i2.4 x 2.43) 5.8 



Total suckling young. 



Tolij/ loss . 



15.3 



^Average size of second-season litters: fox squirrels, 2.57; gray squirrels, 2.43; table 20. 



ginning later than the present one would 

 result in the survival of a much greater 

 number of unborn and suckling squirrels 

 that now are lost through destruction of 

 pregnant and lactating females. 



In the face of the considerations listed 

 above, we feel that it would be unwise to 

 enact a squirrel season beginning ifo late 

 that it would prevent all losses attribut- 

 able to the killing of pregnant and lactating 

 females. Such a season could hardl}' be- 

 gin earlier than October 1, and it would 

 certainly be opposed by a large number 

 of hunters. On the other hand, it is 

 clear that the 1944 season, opening July 

 15 in the southern zone and August 15 in 

 the central and northern zones, is too early, 

 and that such a season results in the death 



of many thousands of squirrels that are not 

 bagged. We suggest as a reasonable com- 

 promise the seasons given in table 28, 

 which takes into consideration the prece- 

 dent for early hunting in the state, the 

 minimum requirements for adequate re- 

 production, and the high productive ca- 

 pacity of much of the Illinois squirrel 

 range. 



It goes without sa>ing that, although 

 the seasons proposed here will result in ap- 

 preciable loss due to starvation of young, 

 this loss will be materially less than at 

 present. In time it may be practical to 

 enact laws establishing seasons that give 

 squirrels greater protection in order still 

 further to reduce juvenile losses. It is 

 not out of place to point out that seasons 



