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Fig. 15. Number of produced recruits per km² by mallards (Anas platyrhynchos), gadwalls (Anas strepera), blue-winged teals (Anas discors), northern shovelers (Anas clypeata), and northern pintails (Anas acuta) during 1987-90 in the prairie pothole region of the United States, based on model projections from aerial videography and ground counts. Landownership classes include easements (easement) where the U.S. Fish and Wildlife Service has easements on wetlands to prevent draining, filling, or leveling; land owned by the U.S. Fish and Wildlife Service (service); privately owned land (private); andall landownerships combined (all). 1987-90. Error bars= 1 standard error.

Fig. 16. Number of produced recruits per mi² of bluewinged teals (Anas discors), gadwalls (Anas strepera), mall ards (Anas platyrhynchos), northern shovelers (Anas clypeata), and northern pintails (Anas acuta) during 1987-90 in the prairie pothole region of the United States, based on model projections from aerial videography and ground counts. Error bars = 1 standard error.

Fig. 17. Recruitment rate of five species of dabbling ducks during 1987-90 in the prairie pothole region of the United States, based on model projections from aerial videography and ground counts. Species include mallards (Anas platyrhynchos), gadwalls (Anas strepem), blue-winged teals (Anas discors), northern shovelers (Anas clypeata), and northern pintails (Anas acuta) and all species combined.

Fig. 18 Average number of successful nesting attempts per km² by mallards (Anas platyrhynchos), gadwalls (Anas strepera), blue-winged teals (Anas discors), northern shovelers (Anas clypeata), and northern pintails (Anas acuta) by landownership class in the prairie pothole region of the United States, based on model projections from aerial videography and ground counts. Landownership classes include easements (easement) where the U.S. Fish and Wildlife Service has easements on wetlands to prevent draining, filling, or leveling; land owned by the U.S. Fish and Wildlife Service (service); and privately owned land (private).