MONTHLY WILDLIFE RESEARCH LETTER 
u. 6 
y^o' 2 " 
Department of Conservation and Natural History Survey, Cooperating 
T. G. Scott, Editor 
Urbar.a, Illinois 
February, 1963 
Vo 1. 6, No. 2 
1. Pheasant Populations and Land Use J. E. Warnock, G. B. Joselyn 
An estimate of the harvest of cock pheasants on the 37-square mile Sibley area 
during the 28^-day hunting season in 1962 indicated that hunters removed 72.2 percent 
of the available cocks. This estimate was based on the change between prehunt and 
posthunt sex ratios; the posthunt sex ratio was corrected for a 7*4 percent illegal 
kill of hens. 
The prehunt sex ratio of 41.7 percent cocks was obtained from 1,821 pheasants 
captured by n ight 1 ight ing during late September, October, and early November, 1962. 
The posthunt sex ratio of 17-7 percent cocks was obtained from observations of 6,931 
pheasants along roadsides during late December, 1962, and January and February, 1963- 
The illegal kill of hens (7*4 percent) was obtained by fluoroscopic examination of 407 
pheasants captured by nightlighting during January and February, 1963; 21 of 63 cocks 
(33-3 percent) and 12 cf 344 hens (3*5 percent) contained lead shot. 
2. Manipu1 at ion of Pheasant Habitat D. E. Newman 
Data collected from manipulated and control plots along 7 miles of rcadway at 
Sibley in 1962 revealed that 50 percent of the nests established in fencerows were 
abandoned and/or destroyed by predators, whereas only 22 percent of the nests located 
in the remaining area of the roadsides had this fate (Table 1). Of the 14 nests that 
were abandoned and/or destroyed, nine were either indirectly or directly disrupted by 
large mammals, two by avian predators, two by farm machinery, and one by an unknown 
cause. 
Table I. Disruption of nests established in different portions of roadside 
areas, Sibley area, 1 962 . Numbers of nests are in parentheses. 
Fence row 
Remaining Area 
Total 
Percent of 
roadside area 
25 
75 
100 
Percent of 
nests estab1ished 
55 (20) 
45 (18) 
100 ( 38 ) 
Percent of 
nests disrupted 
50 (10) 
22 ( 4) 
37 (14) 
W 
natural 
HISTORY SURVEY 
