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Bad weather, which forced waterfowl] to seek food and shelter in the river 
bottoms, can probably be considered as the factor causing such large local 
concentrations. 
In northwest Iowa between April 7-20, the river overflows, natural lakes, 
and sloughs were covered with lesser scaup and a few redheads and canvasbacks. 
These species were also found in large local concentrations in 1952, and not 
widespread throughout central Iowa as in 1951. The build up of diver populations 
in the lakes region was rapid and their numbers reached a peak about April 15. 
Their ranks disappeared more slowly, but by May 1 there were only a few scattered 
survivors, 
There was no discernable blue-winged teal flight through northwestern Iowa 
this spring. The dribble or creep movement of this species, so characteristic of 
blue -wings in the fall, occurred this spring. During the last two weeks of April, 
the blue-wings filtered into and through Iowa leaving resident breeding birds well 
established in the marshes and potholes by May 7. The blue-winged teal migration 
was completed approximately one week earlier this spring as compared to a year 
apo in the Spirit-Okoboji Lakes region. 
Migratory populations of coot observed in Iowa during the spring of 1952 were 
as few as those observed in 1951, 
Weather and Water Conditions 
Lakes, sloughs, and potholes were filled to capacity and overflowing again 
during the spring of 1952. This situation did not continue throughout the breeding 
season as it did the year before. The permanent sloughs (without farm drainage 
tile) maintained near constant water levels, but those countless potholes with 
functional drainage tile went dry after the nesting season began and oat seeding had 
finished. Skimpy rainfall during the middle and late summer was insufficient to 
provide for waterfowl production in tiled potholes, but sufficient to eliminate crop 
production for the second year in a row from these stolen duck hatcheries. 
Generally, weather and rainfall were favorable throughout the State and 
nesting waterfowl were well provided for with the exception of wood ducks. 
Devastating floods along the Mississippi River inundated wood duck nests, causing 
immeasurable losses. It is assumed that the even more serious flooding on the 
Missouri River caused unknown losses to nesting wood ducks. Heavy snowfall and 
rapid thawing beyond the borders of Iowa contributed to these serious flood conditions. 
Late summer rainfall was limited, but of sufficient quantity to maintain 
satisfactory water levels in most lakes and marshes. There was no apparent loss 
of young waterfowl in Iowa caused by lack of rainfall in 1952, Stream flow was 
unstable throughout the State, and fluctuating water levels were common along the 
major rivers and smaller streams. Iowa provided fewer wet areas for nesting 
waterfowl in 1952 than during the extraordinary wet year of 1951. 
Success of the Season 

The trend of waterfowl production in Iowa appears slightly downward as 
compared with a year ago, but equal to production during the nesting seasons of 
1949 and 1950. Wood duck production may have been seriously reduced by floods, 
