Mississippi River Priority Site

Lower Yazoo River, Mississippi

The Yazoo River basin covers about 13,355 square miles of northwestern Mississippi and is the state's largest drainage basin. The Conservancy has designated approximately 1.13 million acres in the lower part of the basin, from about 30 miles northwest of Jackson to the Yazoo's confluence with the Mississippi River near Vicksburg, as a priority conservation site.

The site harbors one of the few remaining large-remnant bottomland hardwood forests along the lower Mississippi. It provides suitable habitat for many species, such as black bear and some songbirds that require sizable blocks of unfragmented woods to thrive.

The pondberry is one of many plant species of concern occurring within the site and is listed as endangered by the U.S. Fish and Wildlife Service. Two endangered species, the pallid sturgeon and interior least tern, as well as rock pocketbook mussels and alligator snapping turtles, have been recorded in the area.

In addition to its endangered and rare plants and animals, the lower Yazoo basin shelters approximately 16 plant communities representative of the Mississippi River's alluvial plain. The Delta National Forest is the only national forest in the United States that preserves a bottomland ecosystem of significant size.

Dredging and bank clearing along the Sunflower River, a major Yazoo tributary, along with alteration of the area's natural water patterns by flood-control projects are negatively impacting many of the site's aquatic species. In some areas, fragmentation of the forest wetlands and forest management practices that have affected the structure and composition of existing forests have rendered wild habitat less attractive, especially for neotropical songbirds seeking to nest.

Through extensive levee construction and ditching, many of the remaining sloughs and oxbow lakes in the lower Yazoo basin have been "cut-off," and the natural hydrology of the area has been critically altered. Agricultural practices such as disking and fertilization threaten freshwater bodies in the region by contributing excessive sediment and nutrient loading.

Strategies and Progress

To promote conservation of the lower Yazoo basin, the Conservancy is seeking to use carbon sequestration funding to encourage the conversion of marginal agricultural land to bottomland hardwood and forested wetland habitat types to expand and connect existing remnant bottomland hardwood forests. Under this model, individual and corporate donations to the Conservancy are used to reforest former agricultural lands, providing more trees to help capture and store carbon from greenhouse gas emissions.

Additionally, Conservancy staff is working with agricultural landowners in the area to promote environmentally-friendly best management practices on production farmland to keep nutrients and sediment on the land and out of the rivers and streams. The Conservancy is also exploring opportunities to restore and enhance some of the services once provided by wetlands and natural river flows, such as nutrient filtering and water retention during major rainfall events, without negatively impacting crop production.

Other Conservancy strategies include:

  • completion of a science-based conservation plan for the site;
  • participation in the Lower Delta Partnership, a coalition of public and private partners dedicated to improving the economic and environmental conditions in the lower Mississippi delta;
  • promoting the reforestation of marginal farmlands adjacent to critical natural areas through government-funded conservation programs containing incentives for landowners; and
  • working with the U.S. Army Corps of Engineers to replicate aspects of the basin's natural water patterns.