Wildlife & Habitat
Tewaukon National Wildlife Refuge (NWR) was established to provide native habitat for prairie and wetland wildlife while providing opportunities for the public to get outside and enjoy the natural beauty of the area.
Changing seasons bring dramatic variations in temperatures, precipitation, sunlight, and plant growth. As the seasons change, so do the species and abundance of wildlife present on the Refuge. As the ice and snow melt, the days begin to lengthen in the spring, and migrating waterfowl start to arrive. In some years, winter gives way readily and many early season plants green up. Other years, winter hangs on well into April. It is certain, however, that spring will bring many migratory birds to the Refuge to feed and rest before moving north. Some birds will nest and raise young in the Refuge grasslands and wetlands. Resident species including mink, muskrat, white-tailed deer, coyotes, and ring-necked pheasants respond to the seasonal weather changes as well.
By early June, spring has faded into summer. Spring migration is complete, and the species that remain are busy raising young. Plants actively grow through the summer months, producing tall native grasses and colorful wildflowers that will feed the visiting wildlife until the coming winter. Summer begins to fade into fall during the month of September. Some years, the heat of summer remains until the end of September, and in others the cooler fall temperatures arrive early. The fall migrants begin to move ahead of the winter that is to come. The first flights of hawks and shorebirds arrive in September to feed on the abundant food resources before heading south. The first snow of the season announces the arrival of winter and signals the migratory bird species that it is time to move on. Some species, such as mallards, Canada geese, bald eagles, and rough legged hawks arrive to spend the long winter with us.
The concentration of wetlands and grasslands found on Tewaukon NWR provides habitat for a very diverse bird population. Over 245 different bird species common to the Great Plains can be found here, along with some unique North Dakota species. Great egrets, upland sandpipers, and prairie sparrows can be observed from April through August. Many species of waterfowl, pelicans, cormorants, herons, and geese use the Refuge for migration and/or nesting. Rails, plovers, sandpipers, and terns have been documented on the Refuge. Of those, many are observed to nest here. Hawks, falcons, eagles, and owls hunt an abundance of prey supported by Refuge habitats. Tewaukon NWR provides habitat that sustains a wide diversity of mammals found on the Great Plains. The wetlands host species such as muskrat, beaver, mink, raccoon and meadow voles. The grasslands support species such as red fox, badger, jumping mice, ground squirrels, and coyote.
Two lakes on the Refuge are open for fishing. Anglers can catch northern pike, walleye, perch, and bullheads on Lake Tewaukon and Sprague Lake. The remainder of the Refuge’s wetlands are managed for migratory birds and are periodically drawn down and allowed to dry out in the summer months. These fish species plus the native fathead minnow are a common prey item for herons, egrets, grebes, pelicans, cormorants, mergansers, terns, and bald eagles.
A diverse array of insects typically found in prairie and wetland environments are present at Tewaukon NWR. Many of our management practices include increasing or maintaining our abundance of insects for prairie and wetland birds. Research has shown that insects are a crucial dietary item for many birds by providing nutrients necessary for egg laying, feather replacement, and muscle tissue growth. Reseeding a diverse mix of grassland plant species provides more opportunities for insects to complete their lifecycles as well as managing our native grasslands through prescribed burning, grazing, and restoring native plants. Managing water level increases the amount of aquatic plants available for insects to feed on and complete lifecycles.
Butterflies are a diverse group of insects and are often very showy. Numerous species of butterflies have been documented on Tewaukon NWR. They are attracted to colorful wildflowers such as milkweed and goldenrods. Many butterflies are tiny and rarely noticed, living out their life grasslands. Some species such as the Dakota skipper and Poweshiek skipperling are very rare and are only found on unbroken tracts of native prairie.
The long cold winters of the Northern Great Plains limit the abundance and diversity of reptile and amphibian species which can survive here. Some snake species do thrive here due to the abundant prey base. The plains garter snake is common throughout the Refuge. Other species include the hognose snake and the smooth green snake. Several species of frogs and toads can be heard more often than they are seen. The chorus frog, northern leopard frog, and plains spadefoot toad are the most common. The painted turtle and the snapping turtle are found in refuge wetlands where they survive the winter by burrowing into the mud bottoms of the wetlands.