MONTHLY WILDLIFE RESEARCH LETTER 
Department of Conservation and Natural History Survey, Cooperating 
Glen C. Sanderson and Helen C. Schultz, Editors i'i.VUlL-l i„L. • 
JAN 2 1972 
Urbana, Illinois 
December, 197l 
Vol. 14, No. 12 
LIBRARY 
1. Pheasant Populations and Land Use 
G. B. Joselyn 
Over the past 10 years, 1962-71, estimates of numbers of pheasant hens 
per square mile on the Sibley Study Area in spring have ranged from a high 
of 95 in 1963 to a low of 26 in 1967- Thus, over the 4 years 1963-67, }t was 
estimated that the density of hens per square mile on the study area in spring 
declined 73 percent. Slight recovery was noted in I 968 (28 hens per square 
mile). The recovery continued through 1971 (46 hens per square mile), making 
this estimate the highest since the estimate of 74 hens per square mile in 1964. 
2 . 
Manipulation of 
Pheasant Habitat 
J 
G. B. Joselyn 
For the 9 years 1 963 - 7 1, density of pheasant nests on seeded roadsides 
( 2.7 nests per acre) was more than double the density of nests on all (mowed 
and unmowed) unmanaged control roadsides ( 1.2 nests per acre), which are 
considered "typical" unseeded roadsides on the study area. 
Density of successful (hatched) nests on seeded plots for the 9 years 
(0.8 successful nest per acre) was slightly more than double the density of 
successful nests on all unmanaged control plots (0.3 successful nest per 
acre). On mowed unmanaged control plots, for the 9 years, density of success¬ 
ful nests was 0.2 per acre, whereas on unmowed, unmanaged control plots, the 
success rate was 0.6 nest per acre. The density of successful nests on 
seeded plots ranged from 0.5 to 1.1 during the 9 years. The density on mowed, 
unmanaged control plots varied between 0.0 and 0.4 successful nest per acre 
during those years; unmowed, unmanaged control plots had from 0.4 to 1.1 
successful nests per acre. 
3. Ecoloqy and Management of Squirrels C. M. Nixon, 
-^ R. E. Greenberg 
During November 1971, a count of squirrel-bui1t leaf nests and potential 
tree dens was conducted in a 70-acre, predominately pole-sized oak-hickory 
forest located in Vermilion County, Illinois 
A total of 205 leaf nests were found and 104 (50.7 percent) were judged 
still serviceable. A total of 64 tree cavities (0.9 per acre) were found 
that could be used for nesting and for rearing litters. The total density 
of leaf nests and dens averaged 2.4 per acre. 
The early-summer squirrel density for this same area was estimated at 
1.7 squirrels per acre. The relatively low number of tree cavities means 
that many squirrels must occupy leaf nests or disperse from the study area. 
