Vo I . 8, No. 11 
Page 4 
Table 2. Acreages, and quail 
on the Forbes, Dale, and Alma 
population changes as 
study areas, I 963 - 65 . 
; determined 
by prehunt censuses 
Area 
1963 
1964 
1965 
FORBES 
Acreage* 
1 ,501 
2,193 
2,193 
No. of Quail 
349 
268 
206 
Quai1 per 100 Acres 
23.2 
12.2 
9-4 
No. of Coveys 
22 
19 
14 
Quail per Covey 
15.9 
14.1 
14.7 
DALE 
Acreage - ! - 
740 
1 ,060 
1 ,100 
No. of Quai1 
297 
286 
203 
Quai 1 per 100 Acres 
40.1 
26.9 
18.5 
No. of Coveys 
17 
18 
14 
Quail per Covey 
17.5 
15.9 
14.5 
ALMA 
Acreage 
— 
6,000 
6,000 
No. of Quai 1 
-- 
220 
1 25 
Quail per 100 Acres 
— 
3.7 
2.1 
No. of Coveys 
17 
10 
Quail per Covey 
— 
12.9 
12.5 
* Excludes a 585-acre lake. 
t Excludes a 200-acre lake. 
5 • Responses of Prairie Chickens to Habitat Manipu 
1 at ion 
R. J. Ellis 
During the past decade prairie chickens have been restricted mostly to a dozen 
or so counties in south-central Illinois. Prairie chickens were able to persist 
in that region because of the extensive acreage of redtop and timothy grown there 
which furnished nesting cover not found elsewhere in Illinois. These grasses were 
most useful to prairie chickens when grown for seed, because mowing was not a 
problem and because a litter of dead grass then accumulated and furnished material 
needed for nest construction. When the grass fields were pastured or harvested for 
hay, litter was sparse or absent. 
The best nesting cover for prairie chickens has nearly disappeared from 
Illinois since 1950. According to Illinois Department of Agriculture bulletins, 
acreages of redtop and timothy harvested for seed have shown a steady decline during 
the past 14 years, dropping from 70 thousand and 25 thousand acres, respectively, 
in 1950 to 5 thousand and 9 thousand acres, respectively, in 1964. For the most 
part the grasslands have been replaced by row crops, which are rarely used by nesting 
prairie chickens. 
If prairie chickens are to be saved in Illinois, it will be necessary to rep lace 
nesting cover in at least a few areas. The minimum of grassy cover needed for each 
remaining flock will be from 300 to 500 acres. 
