Date of this Version
The distribution of breeding waterfowl populations on various wetland habitat types was investigated in North Dakota during 1967-69. Data were obtained by stratified random sampling techniques. The total wetland acreage in North Dakota was estimated to be about 3.2 million acres. Natural basin wetlands comprised about 77 percent of the acreage and 91 percent of the number of wetlands in the state and were utilized by about 76 percent of the state's breeding duck population. Among the four biotic regions of the state, numerical and areal composition of wetlands varied considerably. Natural basin wetlands varied from a low of about 4 percent of total wetland acreage in the Southwestern Slope Region to a high of 93 percent in the Prairie Pothole Region. About 84 percent of the statewide duck population occurred in the Prairie Pothole Region. Within the Prairie Pothole Region, seasonal (Class III) ponds comprised 36 and 23 percent, respectively, of the total acreage and number of wetlands, and semipermanent (Class IV) ponds and lakes comprised 18 and 3 percent, respectively, of these totals. Agriculture has had drastic effects on the wetlands in this region as evidenced by the fact that natural basin wetlands with tilled bottom soils (chiefly Class II and Class III wetlands) comprised about 29 percent of area but 52 percent of numbers of all wet- lands. In the Prairie Pothole Region, seasonal ponds and semipermanent ponds and lakes were utilized by about 48 and 27 percent, respectively, of the total breeding ducks. Optimum environmental conditions for breeding dabbling ducks were present during years when large numbers and acreages of seasonal (Class III) pond basins contained surface water. Semipermanent (Class IV) ponds and lakes were the principal habitats for breeding diving ducks, and were also important to dabbling ducks, particularly during dry years.