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The purpose of this survey was to provide indices to current duck 
brood production through mid-July for comparison with similar indices for 
previous years. A brood chronology survey is being made which provides 
estimates of current hatching curves. At the close of the brood season the 
hatching curves will be used to convert the indices to mid-July brood densities 
to indices to total brood production for the entire season. However, since the 
results of the brood chronology survey are not of immediate use in evaluating 
current brood production, this particular survey is not considered further in 
this report. 
Brood Size Survey 
The brood size survey consisted simply of brood size observations 
collected during the brood chronology survey and during the course of other 
field work. The purpose of this survey was to compare average current brood 
sizes through mid-July with brood sizes during the same period in previous years. 
Water Conditions 
Water Area Densities 
The trend toward poorer water conditions which began in South 
Dakota in 1954 has continued into 1955. Light snowfall last winter with a resulting 
very light spring runoff coupled with below normal rainfall during the early 
Spring resulted in extremely dry conditions at the start of the current waterfowl 
breeding season, 
These extremely poor conditions are reflected in the number of water 
areas of all types observed during the annual survey of the breeding waterfowl 
population in May. The average, state-wide, density of water areas of all types 
was only 2.35 areas per square mile, ‘This is 49 percent below the 1954 average 
of 4.64 water areas per square mile, and is 59 percent below the 1950-1954, 
five-year average of 5.71 water areas per square mile. Current water conditions 
are by far the poorest on record since extensive surveys were begun in 1950, 
Water Area Distribution 
The physiographic distribution of water areas appearing in Table I 
indicates that the 1954-1955 reduction in water areas was severe throughout the 
entire State. This reduction was most severe in the Prairie Hills (70 percent), 
about average in the Minnesota Valley (56 percent) and James River Valley (56 
percent), and least severe in the Missouri Plateau (25 percent} and Missouri 
Hills (20 percent). lt should be pointed out that the fact that the current reduction 
in the western part of the State (Missouri Plateau and Missouri Hills) was less 
severe is due to the fact that this area was already extremely dry in the spring 
of 1954. 
