MONTHLY WILDLIFE RESEARCH LETTER 
Vol. 3, No. 3 
Page 2 
F. Bellrose 
W-55-R-3 
During March, four aerial surveys were made of waterfowl populations in 
the Illinois and Mississippi River valleys. 
As a result of extremely unseasonable weather in March, the spring 
waterfowl migration was most unusual. All through March until the twenty- 
ninth, spring flights of waterfowl were almost nonexistent with the numbers and 
species of waterfowl observed during censuses resembling winter populations. In 
fact, early migrating mallards, pintails, and Canada geese which arrived in 
mid-February decreased in numbers during the first three weeks of March as many 
birds returned south. 
With the warm wave which arrived March 26-29, a flood of waterfowl 
appeared. All species of ducks were observed moving north together, with 
blue-winged teal and pintails in the same flight. 
W-56-R-4 G. Sanderson 
The first draft of a manuscript dealing with amounts of lead found in 
raccoons has been prepared. The average amount in the livers of 101 wild raccoons 
killed by hunters and trappers during November and December, 1958, and January, 
1959, was 6.8 micrograms per gram of liver. Only one test of the 101 livers was 
negative for lead. Lead, in varying concentrations, was found in the livers of 
149 raccoons from 11 widely scattered Illinois counties. 
Significant differences in body conditions of raccoons with widely 
varying concentrations of lead in their livers were not detected. In the absence 
of other obvious stresses such as injury or disease, levels of lead up to 32 
micrograms per gram of liver caused no obvious symptoms of lead intoxication in 
some raccoons. However, some raccoons with pneumonia and lead and some with lead 
but no pneumonia showed symptoms that appeared to be typical of lead intoxication. 
Raccoons appear to be one of the species that are resistant to high levels of lead; 
however, the possibility that lead intoxication contributes to mortality in 
raccoons must not be overlooked. 
Investigations of raccoon and wood-duck relations were resumed on March 
1, by Udell Meyers. 
W-61-R-3 F. Greeley 
J. Ellis 
Eighty-one pheasants were brought from the State Game Farm at Yorkville 
to Urbana on March 7, for the purpose of initiating further studies on the 
calcium-phosphorus complex in laying pheasant hens. The birds were weighed, 
banded, and placed in nine pens. On March 8, nine hens were killed for determination 
of the per cent of bone ash. The remaining 63 hens were reassigned to pens on the 
