The technicians record the location of the nest, the number of eggs, their estimated hatching date, and the height and density of the surrounding upland cover. Then Stephens pushes a long willow branch flagged with orange tape into the ground a few yards from the nest to serve as a visual marker. The researchers will return to check the nest within a week to see if the eggs have hatched or if they have been lost to a predator.
While searching the remainder of the 160-acre pasture, we find more than a dozen duck nests, including those of mallards, blue-winged teal, gadwall, scaup, and shovelers. As we move to other study sites throughout the morning, we find dozens more. By the end of July, Stephens and his research crews will monitor the fate of more than 2,000 duck nests scattered across more than 33,000 acres of native prairie and planted Conservation Reserve Program (CRP) cover.
This monumental effort is part of an ongoing study examining how the abundance of upland nesting cover influences waterfowl nest success across vast prairie landscapes. Stephens' research has significant implications for DU's Grasslands for Tomorrow initiative, which is working to permanently protect 2 million acres of the most productive waterfowl habitat in coteau regions of North and South Dakota.
Dr. Jim Ringelman, director of conservation planning at DU's Great Plains Regional Office (GPRO), explains, "The main objective of our research is to test our assumption that duck nest success and the amount of grassland habitat are directly related. We are particularly interested in native prairie because of our programs that are targeted at protecting these critical grasslands."
Before beginning his field research, Stephens used satellite land-cover imagery to select 18 different study sites-each encompassing an area of four square miles-in five counties in the Missouri Coteau of northwestern North Dakota. Sites were chosen with varying levels of upland cover, ranging from intensively farmed landscapes with very little natural vegetation to nearly solid tracts of native prairie and planted CRP cover. Stephens also considered the abundance of upland cover in a larger, 36-square-mile block surrounding the study areas.