Management and Conservation

Staff at the Upper Souris National Wildlife Refuge use a variety of habitat management techniques to maintain, enhance, and restore conditions for plants and wildlife. They evaluate each situation and choose the most appropriate tools to achieve the desired habitat outcomes.

Refuge management goals include conserving and improving habitat for fish and wildlife, sustaining and restoring native prairie, enhancing waterfowl production, and supporting a diverse community of native species.

Wetland plant communities naturally shift in both species and density as water levels rise and fall. During dry periods, vegetation dies back, preventing wetlands from becoming overly dense for waterfowl. To mimic these natural cycles and maintain open areas beneficial to wildlife, Refuge staff may raise or lower water levels, and may burn, mow or disc wetlands when needed.

Haying and Mowing 

Haying and mowing at the appropriate time of year provide several important benefits to grasslands: 

• Increase plant diversity and overall yield 
• Limit the spread of noxious weeds 
• Reduce the need for herbicides 
• Increase plant density, improving habitat for wildlife 

Grazing 

Upper Souris National Wildlife Refuge uses cattle grazing as a tool to improve grassland habitat for wildlife. While Refuge staff apply grazing to achieve specific habitat goals, grazing cooperators benefit by receiving quality forage for their cattle. The Refuge generally uses short‑duration, high‑intensity grazing practices to support healthy grasslands. Grazing provides several important benefits: 

• Stimulates new plant growth 
• Increases native plant diversity and helps reduce invasive weeds 
• Loosens soil and creates a suitable seedbed for native plants 
• Reduces thatch and recycles nutrients back into the soil 

Local cooperators receive permits to graze designated units. If you would like more information about the grazing program or are interested in becoming a cooperator, please contact the Refuge.

Prescribed Fire 

Prescribed burning is used to manage grasslands much like natural fires once did. Historically, lightning‑caused fires swept across grasslands and marshes, recycling nutrients, clearing out old vegetation, and encouraging new growth. Today, Refuge staff apply prescribed burns to mimic these natural processes and maintain healthy habitat conditions. The benefits of prescribed burning include: 

• Improving native habitats and helping control noxious weeds 
• Reducing thatch and promoting seed germination 
• Increasing nesting and escape cover for birds 
• Stimulating the growth of sprouts that provide food for deer and other wildlife 

Invasive Species Control 

Strategic use of herbicides, combined with biological control species, specifically targets invasive plants on the Refuge and helps prevent these weeds from overtaking the landscape. Because invasive weeds have few natural enemies, insects that feed on these plants are introduced to the Refuge as part of a carefully implemented program. These biological controls, including leafy spurge flea beetles and yellow toadflax stem weevils, target only the specific invasive weed species and help reduce the amount of pesticides needed on the Refuge. 

Water Management 

Lake Darling is a 9,600-acre reservoir named in honor of Ding Darling, the political cartoonist who served as the first director of the U.S. Bureau of Biological Survey, the predecessor of today's U.S. Fish and Wildlife Service. It is the largest of several water impoundments on Upper Souris National Wildlife Refuge and is designed to store a two-year supply of water. Its primary purpose is to provide a regulated water supply to smaller downstream marshes, and to the larger wetlands on J. Clark Salyer National Wildlife Refuge, located 110 miles downstream. The lake also helps maintain water supplies for communities in the valley below during droughts and other low-flow periods.

In addition to providing drought protection, the dam plays an important role in flood management by regulating water releases during periods of high water. In 1998, it became an integral component of the Souris River Flood Control Project, which helps provide 100-year flood protection for the city of Minot.