US Geological Survey


Date of this Version



Published in THE WILSON BULLETIN Vol. 89, No. 1.


The reproductive strategy of the Pintail (Anas acuta) shows several adaptations to the semi-arid variable climate of the prairie pothole region of north central North America where the species is a common breeder. By nesting early and using temporary and seasonal water areas replenished by snow melt waters or early spring rains, the species has successfully occupied broad areas containing limited permanent and semi-permanent water. The Pintail is prone to select new breeding grounds during periods of drought. Smith (J. Wildl. Manage. 34:9@-946, 19701 has shown that part of the population moves northward from the prairies and parklands when widespread drought conditions occur there. Though well-suited for the natural prairie pothole environment, this reproductive strategy makes the Pintail vulnerable to spring snowstorms and modern agricultural practices. In recent years, high cereal grain prices have caused most of the prime Pintail breeding areas of eastern North Dakota to be placed under annual cultivation. Because the Pintail is prone to nest on cultivated lands, it is particularly vulnerable to spring farming operations. The magnitude of direct nest loss attributable to agriculture varies with the chronology of planting operations, size of the nesting population, and timing of nesting. These factors are affected by precipitation patterns. A recent study indicated few Pintail and other duck nests survive when nests are initiated on cropland prior to spring planting operations (K. Higgins, J. Wildl. Manage. in press). Field observations of Pintail hens and examination of reproductive tracts of sampled specimens during the spring of 1970 in eastern North Dakota provided an opportunity to identify nesting patterns and to study their relationship to precipitation, including snowfall, and to agricultural operations.