MONTHLY WILDLIFE RESEARCH LETTER 
MAY 
SlliYiiEY 
1981 
BfcARY 
Illinois Federal Aid Projects W- 66 -R, W- 87 -R, and W- 88 -R 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Eva Steger, Editors 
Urbana, Illinois 
April, 1981 
Vo l. 24, No. 4 
Manipulation of Pheasant Habitat - W- 66 -R r. e. Warner 
The reproductive success of 26 hen pheasants fitted with radio transmitters 
was reported last month (MWRL 24(3):1). This month we consider the survival 
rate of radio-equipped pheasants. 
To examine the relationship of radio weight to survival for all 26 hens, 
the 2 variables, longevity and radio weight, were scored separately because only 
estimates were available in some cases. Hen pheasants surviving more than 3 
months generally were equipped with radio packages weighing less than 27 g (the 
approximate weight of a pheasant egg); r _ ■ -0.71, P « 0.01. 
—tet — 
To predict survival (Y) from the ratio (X) of radio weight to body weight 
(i.e., radio package weight as a percentage of body weight), a regression 
analysis was performed for 15 hens captured prior to or after incubation. 
Longevity information available for this subsaxnple was relatively accurate. The 
ratio for these 15 hens ranged from 2.3 to 3-3; the correlation of X with log Y 
was significant, r = - 0 . 68 , £ < 0 . 01 ). 
The predicted survival in days for the minimum observed ratio of 2.3 was 
229 ± 111 , approximately 30 to 60 days shorter than the average longevity of hen 
pheasants studied on the Sibley Study Area. Hence, it is possible that pheasants 
equipped with radio packages weighing 2 to 3% of their body weight—an unusually 
low ratio compared with other radiotelemetry studies—have a lower survival rate 
than pheasants not equipped with radios. Our data further indicate that hen 
pheasants equipped with radios heavier than the normal weight of an egg have 
little chance of successful reproduction or survival beyond 3 months. 
Ecology and Management of Squirrels - V/- 66 -R C. M. Nixon, 
L. P. Hansen 
A stand of timber can be clear-cut if it has adequate advance oak and 
hickory reproduction (see MWRL 24(3):1-2 for methods used to inventory advance 
reproduction). Oaks will be well represented in the new forest. When a stand 
is about 20 years old, thinnings can be used to select good seed producers and 
promote full crown development to maximize seed yields. Do not thin stands 
below 60% of full stocking so that the residual trees can fully utilize the 
available space. 
