MONTHLY WILDLIFE RESEARCH LETTER 
Vol. 3, No. 9 
Page 3 
One hundred and twenty-four natural cavities believed to have been 
suitable for nesting wood ducks were under surveillance throughout the nesting 
season. This represented an average density of one cavity per 4.5 acres com¬ 
pared with one cavity per 4.9 acres in 1958 and 1959. 
Thirty-four per cent of the natural cavities and 44 per cent of the 
nest boxes were used by wood ducks on the unit containing both nest boxes and 
natural cavities. During the two previous seasons on this same unit, 24 per 
cent of the natural cavities and 19 per cent of the nest boxes were used. The 
increase in use in I960 probably indicates an increase in the population of 
breeding wood ducks. In I960, 39 per cent of all natural cavities were used by 
wood ducks. By contrast, in 1939 and 1940, 51 per cent of the natural cavities 
in the same general area were used. Thirty-seven per cent of 48 nests attempted 
in all natural cavities were successful in I960. This may be compared to an 
average success of 52 per cent in 1958 and 1959. Nesting success in raccoon- 
proof nest boxes was 83 per cent, and 75 per cent of the nests in natural 
cavities protected by "Tanglefoot" were successful. 
Raccoons destroyed 9 per cent of all nests in natural cavities pro¬ 
tected by "Tanglefoot" and 47 per cent of those in unprotected natural cavities. 
High water in bottomlands adjacent to the study area throughout March, April, 
and May caused many raccoons to move to the upland area and probably con¬ 
tributed to the increased depredations by raccoons in I960. Fox squirrels 
destroyed 17 per cent of the nests in natural cavities and 2 per cent of those 
in nest boxes. 
W-61-R-4 J. A. Ellis, W. L. Anderson 
A comparison of the hatching dates of successful nests with the unreal 
ized hatching dates of unsuccessful nests at Neoga provided enlightening infor¬ 
mation on the seasonal timing of the successful nesting of pheasants south of 
the established range. Dates of hatching for successful nests were obtained 
by backdating from the estimated ages of broods aged in the field. The dates 
on which unsuccessful nests would have hatched if successful was determined by 
aging the embryos of unhatched eggs and advancing the date to the probable 
time of hatching. By June 5-11, 50 per cent of the 36 accurately aged broods 
had hatched, whereas the estimated time (June 26-July 2) of hatching for 50 
per cent of the 49 unsuccessful nests occurred 3 weeks later, a time by which 
89 per cent of the broods had hatched. These findings tentatively suggest 
that the major increment of the I960 hatch of pheasants at Neoga was con¬ 
tributed by hens which established nests prior to May 25. 
