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WATERFOWL BREEDING GROUND SURVEY IN IOWA - 1950 
James G. Sieh 
Background and Progress 
ee 
Iowa is in the initial stage of statewide waterfowl production study and 
habitat improvement. Most of the few remaining waterfowl producing areas in north- 
west Iowa are now State owned and managed. Resident area managers (similar to 
U. S. Fish and Wildlife Service Refuge Managers) have been assigned to three 
established management units. It is hoped that permanent ground transects can be 
established on each management unit to provide annual waterfowl! trend data. An 
airplane has recently been added to the State Conservation Commission inventory and 
it is hoped that aerial transects can be established on a statewide basis during 1951, 
Iowa has pioneered in the field of academic research on waterfowl... There 
are six doctoral theses and five masters’ theses dealing with waterfowl production on 
file in the lowa State College Library. Data were gathered for a sixth master's thesis 
during the summer of 1950 in a study of wood duck production on Lake Odessa near the 
Mississippi River in southeastern Iowa. This basic waterfowl research has been 
directed by the Wildlife Unit, Iowa State College; in cooperation with the Iowa State - 
Conservation Commission, U. S. Fish and Wildlife Service, and the Wildlife Manage- 
ment Institute. 
In 1949 the Iowa State Conservation Commission assigned a biologist to 
evaluate the waterfowl resource in Iowa and to gather data dealing with production, 
management, and harvest of this game crop. Meager population trend data were 
gathered for the first time during the breeding season of 1949 and again in 1950. 
Production data have been limited to on-the-spot check counts made on productive 
areas in northwestern Iowa. The three major waterfowl-producing areas in north- 
western Iowa have been named and encircled on the pictorial map to emphasize their 
geographical location. The other lakes and sloughs also represented by dots on this 
map have been spot checked one or more times during the summer to determine their 
value to waterfowl. No serious attempt has yet been made to determine the extent of 
wood duck production along the major rivers in Iowa. It is the opinion of the writer at 
this time that wood duck production in Iowa is increasing, and at present may equal or 
exceed the production of any other species in the State. 
Spring Migration - 1950 
Weather conditions during the spring of 1950 caused delay in the arrival and 
departure of waterfowl in Iowa. Early migrants (Mallards, pintails, and American 
mergansers) reached the Ruthven area following the first spring thaw of March 4 - ‘id 
Several thousand ducks and a few flocks of geese were reported in northwestern lowa 
prior to March 7, 1950. This date, however, marked the first major advance of 
migratory waterfowl across Iowa. There were earlier reports of some migrants 
working northward along the major rivers of the State, but these few were harbingers 
of migrants yet to come. 
On the afternoon of March 7, 1950, low cumulus clouds gathered rapidly in 
northwest Iowa causing rain followed by snow. By night blizzard conditions prevailed 
with 70-mile-per-hour winds. These weather conditions and continued freezing 
temperatures during the two-week period of March 7 - 21 caused a retreat of migratory 
waterfowl from northwest lowa and from the remainder of the State according to all 
available reports. On March 22 thawing weather returned to northwestern Iowa, and 
