3. In the area under study, 205,292 acres (78.45%) are 
open to public hunting and 56,403 acres (21.55%) are in sanc- 
tuary areas closed to hunting. On the Upper Mississippi Refuge 
153,225 acres (79%) are open to public hunting and 40,775 acres 
(21%) are closed. On Mark Twain Refuge no hunting is permitted 
on the managed refuge units. Hunting is carried out on lands 
turned over to the various States and is permitted on the periph- 
eries of the refuge units. 
4, Mass migration flights occurred in 4 years out of the 
15 (in 1947, 1948, 1955, and 1956). In the other 11 years there 
were steady dribblings of birds with no mass movements. 
| 5. Over the 1953-60 period, waterfowl numbers were high on 
all areas during the period of the hunting season. An average 
of 29,965,010 days of duck use occurs on the area under study 
during the period of the hunting season (October 1-December 27), 
amounting to 81.89% of total fall use. The average weekly 
population occurring during the hunting season is 420,150 ducks, 
and the average peak population is 767,140 ducks (the highest 
peak recorded was 1,379,965 in 1953). 
6. On Mark Twain Refuge duck-day use showed a marked decline 
in 1957, the year that the Missouri River reservoirs in the 
Dakotas started holding ducks, and has decreased since that time. 
Many of the ducks using Mark Twain move in from the northwest. 
On the Upper Mississippi Refuge the northwest movement is impor- 
tant only on the extreme south end, and populations did not show 
the dip in 1957 which was so apparent on Mark Twain. 
J» Mallards, comprising 72.40% of the total fall flight, 
also account for 62.90% of the checked kill. On the Upper 
Mississippi Refuge, mallards account for only 37.60% of the total 
flight and 40.30% of the checked kill. 
8. The average number of days of hunting each year on the 
Upper Mississippi Refuge is 102,920 (highest was 129,845 days 
in 1957) and the entire area.averages 135,785 days of hunting 
(highest was 178,285 days in 1954). 
9. During the 15-year period, bag-check data have been 
obtained from 251,876 hunters, having 283,763 ducks, for a daily 
average of 1.12 ducks per hunter-day. The highest average 
recorded for the entire area was 1.64 ducks per day in 1949, while 
the lowest overall average was 0.93 ducks per day in 1958. 
10. The average hunt lasts 5.26 hours on the area under 
study, with the lowest average (4.64 hours) being recorded on the 
Upper Mississippi Refuge and the highest (6.37 hours) near the 
Calhoun Unit of Mark Twain Refuge. 
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