Management Requirements: See Anderson et al. (1974) for bibliography of management findings. See Allen (1986) for habitat suitability index model and information of wetland, timber, and cover type management in relation to winter habitat in Lower Mississippi Valley. See Barker et al. (1990) for information on the effects of different livestock grazing systems on nesting success in North Dakota. See Marcy (1986) for specifications for the construction and placement of wire nest baskets.