
193 
Water Area Densities 
Water Conditions 
In spite of above normal rainfall in parts of South Dakota following 
the survey of the breeding population in May, water conditions for waterfowl 
continued to deteriorate. At the time of the brood density survey in mid-July, 
there were only 1.22 water areas (other than streams) per square mile in eastern 
South Dakota. This is 45 percent below the 1954 average of 2.23 water areas per 
square mile, and is 59 percent below the 1953-1954, two-year average of 2.98 
water areas per square mile in mid-July. 
Water Area Distribution 
The physiographic distribution of water areas in mid-July is indicated 
in Table V. Except for the Missouri Hills, which had about the same low number 
of areas as in 1954 (plus four percent), the density of water areas was down 
considerably over the remainder of eastern South Dakota. The decrease in water 
areas was 69 percent in the Minnesota Valley, 59 percent in the James River 
Valley, and 48 percent in the Prairie Hills. 
Duck Brood Densities 
Duck Production 
The duck brood density survey in mid-July measures the production 
of duck broods through mid-July. It cannot measure or predict the amount of 
brood production for the entire breeding season, but it should serve to predict 
any large scale increase or decrease in brood production. 
The current mid-July survey indicated an observed brood density 
in eastern South Dakota of 0.406 brood per square mile. This is 40 percent below 
the 1954 density of 0.677 brood per square mile, and 42 percent: below the 1953- 
1954, two-year average of 0.69 brood per square mile in mid-July. Since the 
current hatch appears to be considerably earlier than that of 1954, it would appear 
that total brood production for the current season will be at least 50 percent 
below that of 1954. 
Duck Brood Distribution 
The physiographic distribution of duck broods in mid-July is indicated 
in Table V. Brood production at that time was apparently ahead of 1954 production 
in the Minnesota Valley (plus 70 percent), and Missouri Hills (plus 43 percent) 
and behind 1954 production in the Prairie Hills (minus 42 percent) and James 
River Valley (minus 60 percent). 
