The Nature Conservancy has worked to protect the St. Louis River from its headwaters in Minnesota's Northwoods to where it flows into Lake Superior and forms a 12,000-acre freshwater estuary—like none other in the Great Lakes.
The St. Louis River originates north of Two Harbors, Minnesota and flows through some of the region's best lowland conifer forest and peatland for 179 miles before it meets Lake Superior above the twin ports of Duluth and Superior to form the St. Louis River Estuary.
The combination of ecosystems within the Estuary—estuarine wetland and aquatic habitats, baymouth bar complex, its importance to breeding and migratory birds, and its importance to native fish—are very unusual in Lake Superior, the Upper Midwest, the Great Lakes, and around the world.
What TNC Has Done/Is Doing
Threats to the Estuary include loss of habitat due to development, commercial shipping and other sources, increased sedimentation due to development, forest management practices and other sources, competition from undesirable exotic species introduced by commercial shipping and development, exposure to contaminants from historical and current industrial activity, and water quality.
In 2002, TNC assisted the City of Duluth in developing a new law establishing the Duluth Natural Areas Program, which designates for protection special natural areas owned by the city (a major landowner in the Estuary).
To help lake sturgeon recover in the St. Louis River, TNC helped the Minnesota Department of Natural Resources improve spawning habitat for this ancient fish, which can reach a length of more than six feet and live more than 100 years.
In 2010, TNC protected Clough Island, the largest island within the St. Louis River Estuary. The island's size and prominent location make invaluable for wildlife including migratory and breeding birds as well as fish that move between Lake Superior and the river.
TNC also assisted in the effort by Minnesota and Wisconsin fisheries staff to estimate the lake sturgeon population in the river and western Lake Superior by purchasing passive integrated transponder or PIT tags, similar to the ones placed under the skin of pets, that were inserted into approximately 200 adult lake sturgeon. The tags were purchased by TNC thanks to a grant from the Biodiversity Fund of the Duluth Superior Area Community Foundation.
Others that are working to restore the St. Louis River Estuary include:
- St. Louis River Alliance
- Minnesota Department of Natural Resources
- Wisconsin Department of Natural Resources
- Minnesota Land Trust
- Minnesota Sea Grant
- Fond Du Lac Band of Lake Superior Ojibway
- U.S Environmental Protection Agency
- City of Duluth
- City of Superior
- Minnesota Power
- Minnesota Ornithologists’ Union
- U.S. Coast Guard
- U.S. Fish and Wildlife Service
- Natural Resources Research Institute – UMD
- Minnesota Pollution Control Agency
- Carlton County Soil and Water District
- 1854 Authority
- Douglas County
- Numerous private citizens and companies
Today, TNC's work on the St. Louis River is focused largely on its headwaters within the Sand Lake/Seven Beavers landscape. TNC owns and manages more than 6,000 acres and is working with partners to protect and restore more of the region's lowland conifers and sensitive aquatic communities.