MONTHLY WILDLIFE RESEARCH LETTER 
Vol. 2, No. 10 
Page 2 
September. The early start of juvenile breeding in June this year served only 
to keep the juvenile contribution from being lower than what it is. 
W-55-R-4 F. Bellrose 
This project was reactivated on September 24, 1959, when the first autumn 
census was taken of waterfowl populations in the Illinois and Mississippi River 
valleys. Since the initial aerial survey, two other complete waterfowl censuses 
were taken on October 1 and October 7. In addition, a spot check was made on 
October 12 in the Havana region following a pronounced waterfowl flight which 
arrived the night of October 11-12. 
Up to mid-October this year waterfowl populations have been from 1.5 to 
2.0 times larger in the Illinois River valley than they were during the same 
period of 1958. Widgeons and pintails have especially predominated in these 
early duck populations. The large increase in early migrating ducks is attributed 
to the tremendous increase in native duck food plants which were at an all time 
low in 1958. 
In contrast to the increase in early duck numbers in the Illinois Valley, 
there have been fewer ducks along the Mississippi River in September and early 
October of 1959 than the year previously. Waterfowl food plant conditions are 
approximately the same in the Mississippi Valley this year as they were last 
year. 
W-56-R-4 G. Sanderson 
Live-trapping and tagging of raccoons and opossums was begun on the 
Allerton Park study area in Piatt County on April 21, 1959, aid continued 
intermittently through October 29, 1959. 
Seventy-seven raccoons were caught 163 times during this period. These 
included 15 adult males which were caught 20 times, 12 adult females caught 23 
times, 17 young-of-the-year males caught 43 times, and 33 young-of-the-year 
females caught 77 times. 
Male number 30, adult when first caught on May 20, 1957, was retrapped 
once in 1957, five times in 1958, and once in July of this year. Female number 
44, lactating when first live-trapped on July 10, 1957, was retrapped twice in 
1957, once in 1958, and again on July 5th and 13th in 1959. Eleven other adults 
were caught in both 1958 and 1959. 
One hundred twenty-3ix opossums were live-trapped 398 times this year. 
One adult male was caught eight times, and one adult female was caught 29. 
Ninety-one young-of-the-year were caught 244 times. 
No opossums captured in 1957 and only a few of those caught last year were 
caught in 1959. 
