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2. Two ground study areas on the prairies were surveyed intensively 
twice during the summer, once for a breeding population estimate, and a second 
time for brood information. 
3. On all five study areas, ground population and brood counts were made 
at a time to correspond with aerial coverage of the same sections. This was done 
with the idea of attempting to arrive at a measure of the degree of error present in 
aerial survey methods. 
4. Generally speaking, water levels were above normal throughout the 
breeding season, with many areas registering more water in July than in May. 
5. Water body loss on the three parkland study areas varied from a high 
of 40.5 percent (Provincial average 26.7 percent) to a low of 14.3 percent. 
6. Waterfowl breeding populations showed considerable variations in 
density throughout the season in all study areas. 
7. Nest histories were kept on 86 duck and 88 coot nests. Duck nest 
hatching success averaged 58 percent with mallard success 74 percent and pintail 
success 43 percent. 
8. Nest losses were due primarily to predators of which the crows and 
coyotes were most important. The canvasback showed a great sensitiveness to 
human interference where 11 out of 13 nests were found deserted after the observers 
first visit to the nest. It would seem that in the studies described above that the 
human factor in nesting studies was the indirect basis for a majority of all nest 
losses. 
9. Cover-type preference for parkland nesting waterfowl are extremely 
varied, Three species showed considerable one-sided preferences: mallard for 
buckbrush, canvasbacks and coots for hardstem bulrush. 
. 10. At the present time, using only the sample areas from Alberta, it does 
not appear to be possible to measure the degree of error between aerial and ground 
methods of population and brood observations. When information is available from 
the other prairie Provinces or when more samples are studied in Alberta, it may 
then be possible to measure aerial error more accurately. 
11. The brood average for all species on the five intensive study areas in 
Alberta was 6,81 young per brood in 1952. 
12. Local migrations of the broods of puddlers and some of the divers 
makes accurate checks of a resident population very questionable in pothole areas. 
This is particularly true when study areas are linear in form. 
