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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