Northern Prairie Wildlife Research Center
Duck Populations as Indicators of Landscape
Condition in the Prairie Pothole Region
Selection of Study Areas
EMAP systematically divided North America using a grid of 40 km² hexagons.
From this sample universe, we selected as study areas 45 hexagons in North Dakota
east of the Missouri River using systematic sampling (Figure 1). The study areas
were post-stratified into three regions (Red River Valley, Drift Plain, and Coteau)
based on maps by Kantrud et al. (1989).
|Figure 1. Location of 45 40 km² study
areas in North Dakota used to examine duck populations as indicators of
landscape condition, 1995-1996.
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