Good riddance to dangerous rodents

After 20 years of hard work, the Chesapeake Bay can finally say goodbye to the exotic, invasive nutria that has wreaked havoc on swamplands for years.

On Friday, September 16, the Chesapeake Bay Nutria Eradication Project invited US Fish and Wildlife Service leadership, state and federal leaders and local partners to celebrate the rodent’s long-deserved eradication and tour the Chesapeake Bay marshes to learn more about the removal efforts.

Coypu and their destructive feeding habits have devastated thousands of acres of swamps since the 1940s, when they were introduced from South America for the fur market on Maryland’s Delmarva Peninsula.

Coypu have ravaged the Chesapeake Bay swamps; This image shows a wetland damaged by coypu before and after its restoration.

Maryland’s Blackwater National Wildlife Refuge has seen some of the worst of this destruction, losing over 5,000 acres of wetlands due to the combined siege of nutria impacts, sea level rise and land subsidence.

In 2004, total annual losses in economic, environmental, and social services due to coypu damage were estimated at US$5.8 million, with forecasts predicting that they would increase dramatically if coypu were not addressed.

To address the issue, we partnered with the US Department of Agriculture’s Wildlife Services and the Maryland Department of Natural Resources to form CBNEP, which works closely with private landowners and other public partners.

Half of the 14,000 nutria removed during the project came from private property, thanks to over 700 participating landowners who ultimately protected over 250,000 acres of swamps on the Delmarva Peninsula.

To track down and remove the rodents, CBNEP used specialized sniffer dogs trained to track down feces. The dogs and their handlers were key in confirming the absence of nutria in previously enclosed areas.

“Traditional tools like trapping and wildlife surveys have been combined with new technology and tracking dogs by wildlife biologists. These tools have been applied by dedicated individuals to put every nutria at risk, every day of the year. Because of that hard work, partnership, and perseverance, we’re excited to announce the destructive

Learn about the invasive species nutria that will no longer damage and destroy the Delmarva swamps,” said Kevin Sullivan, USDA-Wildlife Services State Director.

Specially trained dogs and their handlers were essential in locating coypu and determining their absence from the salt marshes.

The project was the first of its kind – trying to eradicate an aquatic mammal from a location off the island. The group has been working to completely eradicate nutria from the region for 20 years.

In 2015, the project reached a turning point when the last known Maryland nutria was caught.

Since then, CBNEP has monitored and revisited historic nutria areas to ensure eradication through statistical surveillance. The team has entered a slimmed-down biosecurity phase to respond to all reported sightings and to support other states, such as Virginia, that are experiencing increases in nutria that could potentially reenter the Delmarva if left unchecked.

The removal of coypu augments other ongoing efforts to strengthen the resilience of the Chesapeake wetlands, where sea level rise and historic digging and leveeing efforts are rapidly converting acres of wetlands to open water. Managers have also placed native plants, deposited thin-bed sediments, and restored hydrology to help rebuild swamp processes that the landscape can keep up with

Learn more about climate change. These resilience efforts would not be possible if nutria remained on the Delmarva Peninsula.

The project was funded by the National Wildlife Refuge System and Partners for Fish and Wildlife Program and supported by 27 partner organizations. The service’s Chesapeake Bay Field Office and the Chesapeake Bay Marshlands National Wildlife Refuge Complex managed the project, which was conducted by a team of 17 state wildlife specialists from the Department of Agriculture’s APHIS Wildlife Services.

The invasive rodent nutria has plagued the Chesapeake Bay for decades. Now they are gone for good.

“After years of hard work and partnership, we have proven that eradication of this invasive species is possible,” said Maryland DNR Secretary Jeannie Haddaway-Riccio. “Maryland’s wetlands, particularly in this region, are special because of their ecological and economic importance, but also because of their historical and cultural significance, and we have successfully protected them from this threat.”

“The Chesapeake Bay Nutria Eradication Project is an excellent example of forethought and collaboration,” said Service Director Martha Williams. “This project is a powerful case study of how federal and state agencies can work closely together to achieve a common goal that benefits the environment and the community.”