MONTHLY WILDLIFE RESEARCH LETTER 
:..jy 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C. Schultz, Editors 
Urbana, Illinois 
June, 1971 
Vol . 14, No. 6 
1. Pheasant Populations and Land Use S. L. Etter, 
R. E. Greenberg 
During the 5 - y ear period 1962-66, all of the available indices of 
pheasant abundance indicated pronounced decreases in numbers of pheasants 
on the Sibley Study Area. There were, however, marked differences in the 
magnitude of population losses indicated by summer roadside indices and 
those obtained by other means. 
Summer roadside counts in 1966 recorded 18.7 broods per 100 miles, 
compared with 36.3 broods per 100 miles in 1962, a decrease of 48 percent. 
The number of successful nests projected from sample plots in 1962 and 
1966 were 1,721 and 367 nests, respectively, a decrease of 79 percent. 
Projections based upon cock call counts in 1 962 and 1 966 indicated a 
decrease of 80 percent in late-summer pheasant numbers. The number of 
pheasants flushed per 100 acres, during nightlighting, decreased from 213 
in 1962 to 63 in 1 965 , a decrease of 70 percent. Too few acres were 
nightlighted in 1966 to obtain a valid index. 
These data indicated that the summer roadside counts underestimated 
the magnitude of population losses. Apparently, then, a larger than 
usual proportion of the pheasant population was observed on roadsides as 
the acreages of other types of nest cover and brood cover decreased on 
the adjacent cropland. These findings raise serious questions concerning 
the validity of roadside counts as indices of pheasant abundance and 
suggest that additional data on the acreages and use of other cover types 
by pheasant broods are needed if accurate indices of late-summer pheasant 
numbers are to be obtained. 
2. Manipulation of Pheasant Habitat G. B. Joselyn 
The preceding monthly report (MWRL 14(5)’.1”2) described efforts 
currently under way by Survey and Department of Conservation personnel to 
determine the miles of roadside that have been graded in Ford, McLean^ and 
Iroquois counties in the course of road-maintenance work. These efforts 
are preparatory to determining the feasibility of seeding the roadsides 
with brome and alfalfa. 
Data provided by the Superintendent of Highways of Ford County 
indicate that grading has been undertaken during 1970 and 1971 along 
approximately 64.5 miles of roads in the county (both sides). This is 
