MONTHLY WILDLIFE RESEARCH LETTER 
NATURAL HISTORY SURVEY 
APR i 1971 
MWV»Y 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C. Schultz, Editors 
Urbana, Illinois 
March, I 97 I Vol. 14, No. 3 
1. Pheasant Populations and Land Use S. L. Etter, 
R. E. Greenberg 
Because of the lack of snow cover during the winter of 1970-71; 
posthunt sex-ratio counts on the Sibley Study Area were confined to 3 
days, February 23 and March 11 and 12. During these 3 days, the sex 
ratio indicated by observations of 562 pheasants was 37 cocks per 100 
hens. Comparison of this sex ratio with the prehunt sex ratio in 1970; 
after corrections for differential juvenile survival and illegal hen 
kill, indicated that 50 percent of the available cocks were harvested 
during the hunting season, 1970. Similar calculations for the hunting 
season in 1969 indicated a harvest rate of 43 percent. 
A success rate of 21.4 cocks killed per 100 gun-hours was recorded 
from hunter-interviews on the opening weekend of the hunting season in 
1970. For the corresponding weekend in 1969; hunters reported a success 
rate of 23*3 cocks bagged per 100 gun-hours. 
Although accurate data on the degree of hunting pressure in the 2 
years are lacking, the combination of a higher harvest rate and a lower 
success rate in 1970, compared with 1969; suggests that the fall pheasant 
population in 1970 was slightly lower than in 1 969 » Because of wet 
weather during the fall trapping period in 1970, too few pheasants were 
marked to obtain a valid estimate of the fall population. Hence, sup¬ 
porting data for the decrease in pheasant numbers, suggested by the har¬ 
vest data, are lacking. 
2. Manipulation of Pheasant Habitat G. B. Joselyn 
As a result of recent meetings with personnel of the Department of 
Conservation, the decision was made to attempt to establish an untreated- 
roadside management area. There will be no seeding of roadsides in this 
area. Farmers will be asked to delay mowing of roadsides until late 
summer. Studies of seeded and of unseeded roadsides in the Sibley Area 
indicate that delayed mowing of unseeded roadsides substantially in¬ 
creases utilization of these roadsides by nesting pheasants. It is 
thought that an attempt should be made, on a limited scale, to determine 
the response of farm operators to a request for delayed mowing of 
existing roadside vegetation, with no seeding involved. 
