Northern Prairie Wildlife Research Center
Moist-soil management has been integrated with traditional crop management for Canada geese at Swan Lake NWR. Refuge fields were classified according to drainage and flooding propensity. Flood prone fields are managed primarily for moist-soil plants. One-quarter of these units are disked and planted to a crop such as milo or millet each year to maintain productivity of annuals and prevent encroachment of woody vegetation. The less frequent tillage of these flood-prone lands also minimizes soil erosion. Native seed production on these lands is promoted by carefully timed draw-downs during the years they are not in row crop production (Fredrickson and Taylor 1982). Availability of moist-soil foods, and subsequent goose use, is enhanced by shallow flooding (≤15 cm) timed to goose arrival.
Production and availability of foods can be highly variable among years depending on the timing and severity of drought or flooding. In dry years, production of moist-soil foods occurs despite failure of upland crops; however, food availability may be limited unless dependable water sources allow timely flooding. During moderately wet years, production and availability of moist-soil foods and crops is usually ensured. In wet years, crop production may be poor due to flooding during the growing season, but moist-soil habitats at higher elevations should provide at least moderate food production. During severe fall or spring flooding, wetlands are flooded too deep for foraging; however, foods become available in the flooded agricultural fields. By incorporating moist-soil management with crop management, a diversity of foods and habitats can be provided each year under a variety of environmental conditions.
Corn likely will remain a staple for geese in many areas, but a diversity of foods and habitat should be available to optimize land management capabilities and for optimal benefits to geese. Also, integration of moist-soil areas with upland crops increases the diversity of habitat and foods available in all seasons and conditions, and would be compatible with management needs for other wetland species such as ducks and shorebirds. In this way, management for Canada geese need not be exclusive of other wetland values.