Great Rivers Partnership - LMR Tensas River Basin

Tensas River Basin

The Tensas River basin covers approximately 718,000 acres of the Mississippi River’s alluvial plain in northeastern Louisiana and was once about 90 percent forested. Now, more than 70 percent of it, much of which has been cleared and drained, produces economically valuable crops of food and fiber. The basin still contains some 65,000 acres of forested bottomlands, most of which are protected within the federal Tensas River National Wildlife Refuge and the state Big Lake Wildlife Management Area.

The Nature Conservancy’s Lower Mississippi River Program has designated as a priority conservation site some 1.5 million acres that includes the Tensas basin and additional habitat identified as critical to the recovery of the Louisiana black bear, a subspecies of the American black bear listed as threatened by the U.S. Fish and Wildlife Service. Also located within the site are nine priority bird conservation areas.

Despite extensive alterations, the Tensas basin remains an ecosystem of significant biodiversity, sheltering the largest known population of the Louisiana black bear among its more than 400 mammal, bird, reptile, amphibian and fish species. Among its rare and endangered mussels are the pyramid pigtoe, fat pocketbook and ebonyshell.

Strategies and Progress

Land-use changes within the Conservancy’s designated Tensas basin site have resulted in considerable losses and fragmentation of wild habitat, while stream alterations have brought about declines in the populations of many aquatic species. Specifically, altered streams have contributed to lower water quality, including increased sedimentation. Past forestry practices have altered tree ages and species composition within the area’s forests.

Between the early 1970s and early 1990s, 12 percent of the forests remaining in the Tensas basin disappeared, and the rapid change sparked a concentrated effort to restore the basin. Along with numerous local, state and federal partners, the Nature Conservancy participated in the formulation of a comprehensive watershed restoration plan, including measures to improve water quality and restore bottomland habitat. The Conservancy is also a participant in the area Partners for Fish and Wildlife Program and the Black Bear Conservation Committee.

Results achieved by these and other programs have been substantial. More than 56,000 acres of agricultural lands have been reforested and about 48,000 acres have been enrolled in the federal Wetlands Reserve Program. Almost 4,000 acres of bottomland habitat and some 15 miles of streamside vegetation zones have been restored. In addition, sustainable management practices are being implemented on agricultural and forest lands, erosion-control structures have been built to reduce sedimentation, water-quality monitoring has been improved and ongoing educational programs are aimed at increasing public participation in efforts to conserve the Tensas basin.

The Conservancy is also working to expand the amount of publicly held land within its Tensas basin conservation site.

What's to Gain?

In addition to benefiting a host of species in need of conservation attention, the numerous efforts under way in the Tensas basin evidence an existing impetus for restoration of a large-scale watershed within the Mississippi River alluvial plain, the success of which could serve as an example for other lower Mississippi watersheds of similar size and biological significance.

Tensas River Basin

LMR Program

Priority Sites

Quick Links

TensasRiver Map

The Nature Conservancy and its partners work at sites along the entire length of the Mississippi River, from its headwaters in Minnesota to the Gulf of Mexico.