Invasive species management

Nutria Eradication Project

Protecting and Conserving Communities of the Delmarva Peninsula

Nutria (Myocastor coypus) are invasive, semi-aquatic, South American rodents first released into Dorchester County, Maryland in 1943. Nutria are not native to Maryland's wetland ecosystems; therefore, there are few predators or natural conditions to control their population. Since their release, nutria have destroyed thousands of acres of wetlands through their damaging feeding habitats. In the Chesapeake Bay, nutria are primarily limited to the Delmarva Peninsula, where they have been found in six Maryland counties and portions of Delaware and Virginia.

Nutria eat the roots and above ground vegetation of marsh plants, resulting in the loss of thousands of acres of marsh habitat. Scientific studies have shown that damage to marsh and shallow water habitat has resulted in the decline of oysters, crabs, fish, and waterfowl. 

The effort to rid nutria from Maryland began in 2002, following a 2-year pilot project to determine if they could be eradicated from the Chesapeake Bay and, if they could be, determine whether nutria damaged marshlands could be restored. The Chesapeake Bay Nutria Eradication Project, under a management team initially composed of representatives from the U.S. Fish and Wildlife Service, Maryland Department of Natural Resources, Tudor Farms, U.S. Department of Agriculture, and University of Maryland, began the first phase in April 2002. The USDA's Animal and Plant Health Inspection Service, (APHIS) Wildlife Services, assumed primary responsibility for project implementation.

Biologists utilized a variety of techniques to locate nutria and monitor the success of trapping and removal. These included: releasing sterilized nutria outfitted with tracking devices to locate additional nutria; boat, shoreline, wetland, and platform surveys; hair snares; and most recently detector dogs.

As of 2018, all the known nutria populations have been removed from over a quarter million acres of the Delmarva Peninsula. No nutria have recently been detected. The Chesapeake Bay Nutria Eradication Project is continuing monitoring efforts to detect any residual animals and coordinating with Landcare Research to analyze data to apply statistical confidence when eradication is declared.

The Chesapeake Bay Nutria Eradication Project also includes restoration and protection efforts. Damage to wetlands and waters must be repaired to conserve fish and wildlife habitats, as well as sustain commercial and recreational activities. Marshes on the Delmarva Peninsula are evaluated and prioritized for conservation efforts. Biologists from Maryland, Delaware, and Virginia; Federal agencies; and non-government organizations are partnering with coastal engineers to use the newest scientific techniques for marsh restoration.

Habitat protection improves the Chesapeake Bay landscape's resiliency to climate change climate change
Climate change includes both global warming driven by human-induced emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. Though there have been previous periods of climatic change, since the mid-20th century humans have had an unprecedented impact on Earth's climate system and caused change on a global scale.

Learn more about climate change
by protecting corridors for marshes to migrate as sea level rises. Federal, state, local, and non-governmental organizations protect habitat through tools such as conservation easements. By combining the strengths of all partners, we can conserve the wildlife and public use of the Delmarva Peninsula for the future.

Go to Saving the Bay: The Chesapeake Bay Nutria Eradication Project to view the entire story.

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