Northern Prairie Wildlife Research Center
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Fig. 1. Relation between estimated nest
initiations per pair ( i
) of northern pintails and mallards (Anas platyrhynchos) and
percentage of wetlands containing water in mid-June (PW) at the Woodworth
study area, Stutsman County, North Dakota, 1966-81. |
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| Fig. 2. Percentage of northern pintail (Anas acuta) nest site visual obstruction measurements (VOMs) and percentage of field transect VOMs by vegetative height class in the Koenig study area, McLean County, North Dakota, 1981. |
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| Fig. 3. Percentage of northern pintail and mallard nests in each visual obstruction measurement (VOM) class in the Woodworth study area, Koenig study area, and Central Grasslands Research Station, Stutsman and Kidder counties, North Dakota, 1975-86. |
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| Fig. 4. Regression of the nest site attractiveness index (A) of northern pintails and mallards on visual obstruction measurements (VOMs) in the Woodworth study area, Koenig study area, and Central Grasslands Research Station, North Dakota, 1975-86. |