WISCONSIN—Observed on Feb. 2, World Wetlands Day 2024 is a reminder that wetlands are a source of numerous benefits for people and other living creatures — and that human activities are a major factor in their loss. These sensitive ecosystems, where water covers the soil or sits at or near its surface, provide habitat for unique species and improve water quality by filtering out pollutants and absorbing and storing water. 

Protecting wetlands is a big concern during any project on a national forest, but this depends first and foremost on knowing where they are. In the northern forests of the Great Lakes states, dense forest cover and the sheer multitude of small wetlands have made it particularly difficult to obtain complete wetland maps. 

That’s why national forests in Wisconsin, Minnesota and Michigan are leveraging partnerships and technology to accurately map these challenging landscapes. What’s at stake is their ability to protect wetlands while still meeting the USDA Forest Service’s multiple use mission. With improved mapping, wetlands can be protected during vegetation management, timber sales and other activities, even when deep snow cover makes them invisible on the ground. 

Over the last three years, the Chequamegon-Nicolet National Forest has worked with the Wisconsin Department of Natural Resources to map wetlands across the forest using light detection and ranging, or LiDAR, visualization techniques. Under a Good Neighbor Authority agreement, the partners mapped 78,028 acres of wetlands in 2023. Field reviews indicated that the mapping results were highly detailed and accurate, leading to a 38% increase in mapped wetland acreage for those watersheds. The improved maps are available to the public through State and National Wetland Inventory databases. This effort builds on work supported by GNA to inventory road-stream crossings, assess risk and replace structures with high risk and environmental impact.

Meanwhile, efforts are underway in Minnesota to map seasonal ponds in forested areas. These are small, hydrologically isolated wetlands that dry up at some point in the year. Seasonal ponds are particularly important as a refuge and breeding area for unique species, while also storing water and enhancing water quality like other wetlands. Yet they often exist under forest cover and may not be identified on existing maps. 

To refine seasonal pond mapping and management, Northern Research Station scientists have worked with the Chippewa and Superior national forests and the University of Minnesota Natural Resources Research Institute. A published review article lead authored by a Michigan Technological University scientist supports identification and practical protection measures for seasonal ponds in the western Great Lakes states.

Both the Chippewa and Superior are engaging in efforts to map and verify seasonal pond locations. For example, over 640 ponds have been mapped and verified within the Pike Bay Experimental Forest on the Chippewa, with an additional 65 mapped ponds remaining to be verified. Unmapped ponds are also being located to test the accuracy of mapping methods. 

In Michigan, the Hiawatha National Forest is mapping seasonal ponds through a partnership agreement with The Nature Conservancy and Michigan Technological University. Inventories and field validation are planned for out-year timber sales to ensure that these unique aquatic habitats are protected during vegetation management. The project is currently in its mapping stage, with field inventories by Michigan Tech students planned for spring 2024. The Hiawatha hopes to secure additional funds for the critical work to continue and expand across the forest.  

This collaborative work taking place across the Eastern Region is an investment in the future, explained regional hydrologist Sheela Johnson. 

“With all the benefits wetlands provide to humans and other living beings, it’s good to know that Forest Service staff and partners are looking out for them,” Johnson said. “Thanks to their work, these benefits will exist for years to come.”