W-42-R-10 
Vol. 3, No. 12 
Page 2 
R* D. Lord, Jr. 
The project leader attended the Mid-west Wildlife Conference in Toronto, 
Ontario, where two papers were presented. One paper was concerned with age compo¬ 
sition and mortality rates of the Illinois deer population as determined by the 
lens technique. The other paper was on the diseases of cottontail rabbits. This 
paper was prepared by Deam Ferris; however, Ferris was unable to attend the con¬ 
ference, and the paper was presented by Lord. 
Three new cases of Ferris’ torticollis disease have occurred in the penned 
rabbits being held for behavior observations. Fortunately, these rabbits were ob¬ 
tained while still alive, and all were submitted to detailed investigations of the 
cause and nature of the disease. The appearance of this disease in winter for the 
first time has important implications concerning the epizootiology of the disease. 
Formerly it was thought that vectors such as ticks or mosquitoes might be impli¬ 
cated in the transmission of the disease. However, in this instance, such vectors 
were not known to have been present. 
W-55-R-4 F. C. Bellrose 
The last large duck flight of the season occurred on November 28 and 29. 
An aerial census of waterfowl populations in the Illinois and Mississippi River 
valleys on December 1, revealed the presence of 1,157,000 ducks, an increase of 
over 500,000 from November 23. This was the largest number of ducks recorded at 
any one time during the 1960 season, and larger than at any time during the 1959 
season. 
A census of the same area on December 14, showed only 661,000 ducks present. 
Snow and cold weather was responsible for the departure of almost 500,000 mallards 
during the second week of December. 
W-56-R-4 G« C. Sanderson 
As mentioned in a previous report, 10 times as many trap nights were re¬ 
quired to catch one raccoon on the Piatt County study area in 1960 as in 1959. 
Thus, only 16 raccoons were live trapped on the study area in 1960 prior to Sep¬ 
tember 1. After September 1, trapping success improved as young raccoons began to 
enter the traps (in a normal year young raccoons begin to enter the traps in June); 
however, all animals trapped after September 1 were removed from the area in order 
to reduce the population. By the end of December, 5 of the 16 marked raccoons, or 
31.2 per cent, had been removed from the area. These five included three which 
were live trapped and two which were killed by hunters. In 1959, 21 of 71 (30%) 
of the marked animals had been killed by hunters and trappers by the end of Dec¬ 
ember, and, in 1958, slightly less than 2D per cent had been killed by the same 
time. Thus, although the number of marked animals killed by the end of December 
declined this year, the percentage killed was about the same as it was in 1959. 
In addition to the five raccoons mentioned above which were trapped in 1960 
and later harvested, two animals tagged during previous years were removed. 
