Vol. 20, No. 5 
Page 3 
not exposed to nest boxes. Thus far we have been unable to demonstrate any 
significant improvement in recovery rates of tagged adult fox squirrels that 
was attributable to nest boxes. For 1976-77, the November-to-March recovery 
rate for adult males using nest boxes was 35*7 percent (12/14); for adult 
males not exposed to nest boxes the recovery rate for the same period was 
30.0 percent (12/15). Corresponding rates for adult females were 90.0 percent 
(9/10) and 72.7 percent (8/11). 
Adult fox squirrels are dominant over subadults and usurp the better 
den sites, usually tree cavities. Subadults are forced to use leaf nests or 
nest boxes (if nest boxes are not considered "choice" nest sites) for shelter. 
Use of nest boxes may also require a learning process by all age-classes of 
squirrels. We have found that individual squirrels that are captured in a 
nest box during the winter are quite likely to be captured in a nest box the 
next winter. There are some adults of both sexes who reside in areas containing 
nest boxes but have never been captured in one and may make no use of them. 
Fox squirrels seem to know the locations of all leaf nests and tree 
cavities within their individual ranges and use them when expedient. Parti¬ 
cularly in winter, however, squirrels seem to remain in the same nests or dens 
for extended periods. When released from live traps, squirrels will often run 
several hundred yards to favored den sites, passing several potential dens. 
Responses of Prairie Chickens to Habitat Manipulation R. L. Westemeier, 
D. R, Vance 
A total of 137 prairie chicken cocks were counted on five census areas in 
four counties of south-central Illinois in the spring of 1977* This total was 
12 percent lower than counts made on the same census areas plus two others in 
1976. 
In contrast to the managed flocks near Bogota in Jasper County, and Farina 
and Kinmundy in Marion County, which collectively declined 7 percent, the 
unmanaged flocks near Mt. Erie, Bible Grove, Hoyleton and New Minden declined 
53 percent. 
Although the Farina and Kinmundy areas are censused separately, they are 
close enough so that an interchange of prairie chickens between the two areas 
is likely. Combined, these two areas showed a drop of 5 percent, which is 
similar to the 7 percent drop at Bogota since the spring of 1976 (MWRL 20(4):3)* 
Viewed separately, between 1976 and 1977 the Farina flock declined from 41 
cocks to 30 cocks (-27 percent), but the Kinmundy flock increased from 16 
cocks to 24 cocks (+50 percent). The count of 30 male prairie chickens at 
Farina is about average for the long-term mean starting in 1963, but the count 
of 24 males at Kinmundy is the highest achieved since the first count in 
1964, As in Jasper County, the booming grounds in Marion County were 
established on or in close proximity to sanctuaries--except in minor instances 
involving one to three cocks. 
