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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).

Location map of study areas.
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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