MONTHLY WILDLIFE RESEARCH LETTER 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C. Schultz, Editors 
Urbana, 111inois 
April, 1969 
V/o 1 • 12, No. 4 
1. Pheasant Populations and Land Use S. L. Etter, R. E. Greenberg 
During the period April 17-29, 1968, all passable roads on the Sibley Study Area 
were driven a total of eight times in order to observe pheasants. Each observation 
period began at sunrise and continued until the entire area (80 miles) 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 April period, 1,223 observations (480 cocks, 743 hens) were 
recorded during the 5 hours following sunrise. The sex ratio of pheasants observed 
during the first 2 hours after sunrise was 60 cocks per 100 hens; the sex ratio for 
pheasants observed during the ensuing 3 hours was 108 cocks per 100 hens. A similar 
increase in the proportion of cocks among pheasants observed during the period from 
2 to 5 hours after sunrise was also noted in 1967 (MWRL 11(4):1). In addition to 
changes in observed sex ratios, the total numbers of pheasants observed declined 
drastically after the first 2 hours after sunrise. Only 373 (31 percent) of the 
1,223 observations were recorded later than 2 hours after sunrise. 
As a consequence of these findings, roadside observations of pheasants to obtain 
indices of breeding populations in 1969 and future years will cover only one-half of 
the roads (40 miles) on the study area during each ear 1y-morning observation period. 
2. Manipulation of Pheasant Habitat 
G. B. Joselyn 
Since 1963; vegetation on seeded and on managed control roadside plots has been 
studied to determine changes in plant-species composition (frequency of occurrence) 
and the percentages of top cover contributed by various species (MWRL 11(6):1-2). 
The contribution of bromegrass ( Bromus spp.) to total top cover was low the first 
year after seeding (20 percent) but increased substantially each year thereafter and 
accounted for 77 percent of the top cover on plots 6 years of age. At the same time, 
alfalfa (M edicag o sativa ) accounted for over 31 percent of the top cover on 1-year-ol 
plots but decreased to only 13 percent on 6-year-old plots. Red clover (Trifolium 
pratense ) contributed significantly to total top cover only the first year after 
seeding (14.8 percent); by the second year this species made up only 1.6 percent of 
the total top cover and less than 1 percent each year thereafter. Timothy (Phl.eum 
pratense) accounted for about 15 percent of the top cover on 1-year-old plots, nearly 
23 percent the second year, but decreased to 5 percent by the sixth year. Grass 
weeds and broadleaf weeds made only insignificant contributions to total top cover in 
plots in all age classifications (less than 10 percent). 
The dominance of brome on the plots can be expected to increase as the plots 
continue to age. Thus, while the frequency of occurrence of alfalfa on the plots has 
remained relatively high (occurring in 54 percent of the quadrats taken on 6-year-old 
