MONTHLY WILDLIFE RESEARCH LETTER 
Vol. 3, No. 7 
Page 2 
raccoon and opossum population may have declined sharply during the past year. 
The opossum population may have suffered heavier than usual mortality during the 
deep and prolonged snow of the past winter, for those trapped in early Spring 
were in unusually poor condition. It is doubted, however, that raccoons suffered 
any unusual degree of mortality during the heavier than usual snows. Indications 
other than those based on trap-nights on the study area and elsewhere are that the 
raccoon population is still at a high level. 
The study of wood duck nesting in natural tree cavities in the Havana area 
has been completed for the I960 season. Forty-Height nests were found on the 
683-acre study area and observations at 7- and 11-day intervals revealed the 
following: 18 successful nests, 18 destroyed by raccoons, 8 by squirrels, 2 by 
snakes, and 1 lost because of tree damage. One unincubated dump nest was found. 
Because regression of the ovaries of wood ducks does not begin until 
after incubation begins, destruction of a nest prior to incubation does not 
necessarily mean that hens which were unsuccessful with their first nest were 
unsuccessful for the whole season. Of the 18 nests destroyed by raccoons and 
the 8 destroyed by squirrels, 4 each were destroyed prior to incubation. 
The increased nest depredations by raccoons this year resulted when 
flooding in the lowlands caused many raccoons to move to upland areas while 
wood ducks were establishing their nesx,s. Depredations by raccoons on wood 
duck nests were higher during the early part of the nesting season than during 
the latter part. 
W-61-R-3 J. Ellis, W. Anderson 
A breeding population of 260 pheasants (84 cocks and 176 hens) has been 
located on the Neoga area. The estimate of the number of cocks is reasonably 
accurate; however, the hen estimate is lower than the number of hens actually 
present on the area. The sex ratio among pheasants released at Neoga last 
winter was 4.5 hens per cock. Sex ratios obtained from subsequent observations 
of pheasants in the field was near the sex ratio of released birds. Thus, a 
more representative estimate of the hen population can be obtained by multiplying 
the number of cocks located (84) by the sex ratio of the released birds (4.5). 
This produces an estimate of 378 hens. 
Forty-eight individual pheasant broods have been observed on the Neoga 
area during June and July, I960. The average number of observed chicks per 
brood was 8.4, and the individual broods averaged 4.3 weeks in age. 
Among 81 adult pheasants observed on the Neoga area during July, 74 
birds (91 per cent) were identified as wild transplants, 3 as game farm birds, 
and 4 were unidentified as to origin. Thus, the "California” birds have 
apparently contributed little to the population. 
