MONTHLY WILDLIFE RESEARCH LETTER 
Vol. 3, Ho. 9 
Page 2 
W-42-R-10 R. D. Lord, Jr. 
The project has moved ahead on several fronts this month. Traps were 
repaired and painted and live trapping was begun on the Allerton study areas. 
Small samples of blood were taken from the rabbits for testing for Shope’s 
fibroma and myxomatosis. 
Experiments designed to determine the pattern of activity were begun 
with two rabbits which were placed in a room which is periodically blacked out 
to determine the ability of the rabbits to maintain their normal pattern of 
activity. In a study designed to determine the nightly range of the cottontail, 
a small harness containing a battery and bulb has been developed and field 
tested with success. Next month this apparatus will be used to trace the entire 
night’s activity of several rabbits. 
Data have been compiled concerning the gain in weight of juvenile 
rabbits on the Allerton study areas. When fully analyzed these data will 
describe a growth-rate curve for the cottontail which will enable estimation of 
ages of young cottontails. The number of measurements made is larger than 
those reported by other investigators and should make age determination of 
living rabbits more exact. 
W-55-R-4 F. C. Bellrose 
Three aerial surveys of waterfowl populations were carried out in the 
Illinois and Mississippi River valleys in September. The surveys were exactly 
one week apart, commencing on September 14. 
The numbers of ducks observed during this period increased from an 
estimated 41,000 to 66,000. The most numerous species in order of abundance 
were: blue-winged teal, green-winged teal, widgeon, pintail, wood duck, and 
shoveler. 
In comparison with other years, blue-winged teal and pintail popu¬ 
lations have been appreciably below normal. Because the blue-winged teal 
migration is almost over, it is apparent that the population of this species 
is down appreciably in the Mississippi Flyway. Green-winged teal and widgeon 
numbers have been above normal. 
W-56-R-4 G. C. Sanderson, U. Meyers 
The data on raccoon-wood duck relationships near Havana were compiled 
for I960. Wood ducks arrived 2 to 3 weeks later than they did the previous two 
years. This was thought to have been a result of the unusually heavy snows and 
below freezing temperatures in March. There was a corresponding delay in 
establishment of nests. 
