Wetlands are areas where water covers the soil, or is present either at or near the surface of the soil all year, or for varying periods of time during the year including during the growing season. There are many different types of wetlands, but management at Hagerman National Wildlife Refuge focuses primarily on Moist Soil Units (MSU’s).
The refuge has about 300 acres of MSU’s – areas where water is impounded by dikes so depths can be controlled. Vegetation including sedges, rushes, native millet, pondweed, and smartweed is often mowed or disked, and water levels are raised or lowered to prepare for arriving wading birds, shorebirds, or ducks. Flooded MSU’s create lush wetlands and a unique diversity of habitat that is attractive to a variety of resident and migratory birds. Vegetated wetland marshes are perfect for nesting and brood rearing because the abundance of aquatic plants and invertebrates provide valuable forage for adults and young. Birds commonly seen in wetlands include puddle ducks such as mallard, shoveler, pintail and teal; wading birds such as great blue heron, great egret, snowy egret, and white-faced ibis; and shorebirds including greater yellowlegs, killdeer, sandpipers, and plovers.