MONTHLY WILDLIFE RESEARCH LETTER 
NATURAL HISTORY SURVEY 
JUN 17 1968 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C, Schultz, Editors 
Urbana, Illinois April, 1968 Vol . 11, No. 4 
1, Pheasant Populations and Land Use S. L. Etter, R. E. Greenberg 
During the period April 17-27, 1967, all passable roads on the Sibley Study 
Area were driven a total of 9 times in order to observe pheasants. The obser¬ 
vation period each morning began at sunrise and continued until the entire area 
had been covered. Starting points were staggered so that no one portion of the 
study area was consistently covered earlier than other portions. 
For the above period, a total of 1,109 observations (367 cocks, 742 hens) 
were recorded during the 5 hours following sunrise. The sex ratios of pheasants 
observed during the 1st, 2nd, 3rd, 4th, and 5th hours after sunrise were 39» ^5, 
53, 83, and 78 cocks per 100 hens, respectively. The consistent increase in 
the proportion of cocks apparently results from a greater association of hens with 
cocks before and during the 1st hour or so after sunrise than during the later 
hours of the morning. Territorial cocks remain relatively conspicuous throughout 
most of the day, but hens apparently retire to loafing areas not readily observable 
from the roadsides. Secondly, many inactive hens unaccompanied by the more 
conspicuous cocks are probably missed against the background of plowed ground. 
Because of the sex differential in the behavior of pheasants during the April 
17-27 period, the observed sex ratios probably overestimated the proportion of 
cocks in the population. Whether the sex ratios obtained during the first nour 
after sunrise indicated the true sex ratio is unknown. 
2. Manipulation of Pheasant Habitat G. B. Joselyn 
A trend toward minimum mowing of state highway roadsides has been noted in 
recent years. This development is desirable from two standpoints: economy of 
maintenance and wildlife conservation. However, before any extensive changes in 
policies of roadside maintenance are made, more information should be obtained to 
evaluate: 
1. Any change, possibly due to reduced mowing schedules, in the hazard 
created when wildlife species strike vehicles. 
2. Public reaction to unmowed grasses and legumes beyorH the ditch line. 
3. Management practices: whether reseeding of roadsides is necessary, or 
whether fertilization or other management of existing vegetation will suffice to 
make roadside vegetation acceptable to both the traveling public and ground-nest¬ 
ing birds. 
In an attempt to answer some of these questions, the Illinois Division of 
Highways, the Department of Conservation, and the Natural History Survey have 
