Great Rivers Partnership - Mississippi River: Ecological Threats

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Other Priority Sites

Cat Island - Tunica Hills

Cypress Island

Dahomey

Donaldson Point - Reelfoot Lake

Lower St. Croix River

Lower Yazoo Basin

Mackinaw River

Military Ridge Prairie Heritage Area

Mingo Basin

Obion Creek and Bayou de Chien

Pecatonica River

Pine City Natural Area

Root River

Sand Ridge Lands

Spunky Bottoms

St. Francis National Forest

Tensas River Basin

Weaver Dunes - Zumbro River

How We Protect Watersheds

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In the Mississippi River basin, as in other great river systems around the world, our long-term economic welfare and the ecological health of our natural resources are inextricably bound. With woodlands reduced, forestry is no longer a powerhouse of the regional economy. Declining groundwater resources are clouding the future of agricultural production in some areas. Commercial fishing has suffered as fish populations have declined.

Increasing knowledge of the value of wild habitats and the need to protect natural systems to ensure adequate supplies of fresh water is prompting citizens, policymakers and conservationists to seek a balance between the needs of human beings and those of the river.

An initial step in this effort has been the identification of several pervasive threats to the river's historically rich diversity of life. They are:

Altered hydrology. Locks and dams, which maintain water levels at low-flood stage for navigation, are slowly degrading many acres of floodplain, side channel, backwater and island habitats. Other river management practices such as cutoffs, revetments, wing dikes, and dredging are causing the river to incise, or cut down deeper, which is accelerating erosion up almost all of the rivers tributaries.
Isolated floodplains. Levees along the river prevent seasonal floodwaters from reaching much of the river's original floodplains, thus isolating a critical component of riverine habitat. These changes also diminish river function by interrupting and altering the flow of sediment.
Habitat loss and fragmentation. About 66 percent of the river's upper basin has been converted from native prairie, savanna and forest to agricultural use. In the lower basin, forested wetlands have been reduced from more than 24 million acres to less than 5 million acres. The coastal wetlands of Louisiana are disappearing at a rate of 25 to 35 square miles a year due to altered water flows and erosion.
Reduced water quality. Increased sedimentation and run-off of excess nutrients from some converted agricultural fields has reduced water quality, particularly in streams and lakes where adjacent wetlands no longer are present to filter the freshwater flows that renew them. Increased runoff carries sediment and nutrients from agricultural watersheds. This has an impact on local water quality and has cumulative impacts on the Mississippi River and Gulf of Mexico.
Invasive species. Invasive species like zebra mussels and bighead carp place additional stress on declining native species, generally through direct competition. Sometimes they stress habitats themselves through sheer numbers.
Climate change. Human-induced climate change will likely affect freshwater habitats in the region by altering snowfall, rainfall and temperature patterns. These changes could lead to regional extirpations of native plants and animals and dramatic shifts in vegetation types.