Chesapeake Bay Nutria Eradication Project
Northeast Region


History of Chesapeake Bay Nutria Eradication Project

Efforts to control nutria began in the mid-1950’s, shortly after animals introduced for research and fur-farming were released or escaped from captivity. Varying levels of seasonal control were achieved over the next twenty years, but were generally unsuccessful at keeping populations from expanding into the tens of thousands.

In 1993, the Maryland Department of Natural Resources (MD DNR) and the U.S. Fish and Wildlife Service (USFWS) established the first multi-agency task force to investigate potential approaches to combat nutria populations. In 1994, Dr. Morris Gosling visited from Great Britain where he had successfully led a program to eradicate nutria. Dr. Gosling assessed the problem and affirmed that eradication was an achievable goal if additional information was collected on how nutria behave and reproduce in Maryland’s habitats, which are distinctly different from habitats found in Great Britain. Two major questions needed to be answered before Congress would appropriate funding: Were nutria a major factor in causing marsh loss? And if nutria were eradicated, would the marsh recover? In 1995, the MD DNR and USFWS, with assistance and direction from the U.S. Geological Survey (USGS), initiated a study that statistically addressed these two questions, provided scientific support that nutria were the primary cause of recent marsh loss, and determined that the damaged marshes would recover within one year if nutria were removed.

In June 1997, the MD DNR and USFWS convened the “Nutria Control Summit” in which representatives from 17 federal, state, and private organizations were invited to develop ideas for nutria eradication in Maryland. This effort culminated in July 1998 with the development of a three year pilot plan entitled Marsh Restoration: Nutria Control in Maryland to Evaluate Nutria Eradication. The objectives of the plan were to: 1) Develop methods and strategies to reduce nutria in Chesapeake Bay wetlands to the point where they are unable to maintain a sustainable population; 2) Restore marsh habitats; and 3) Promote public understanding of the importance of preserving Maryland’s wetlands. Strategies included development of accurate population estimates, determining effective trapping strategies to maximize nutria harvest and minimize the impact on non-target species, evaluating the effects of population control on nutria home range and movement patterns, determining how population control affects nutria reproductive behavior, and determining if the health of nutria populations would be influenced by intense harvest pressure.

On October 20, 1998, H.R. 4337 was introduced by Congressman Wayne Gilchrest during the 105th Congress and was enacted as Public Law 105-322 . On October 30, 1998, President Clinton signed PL 105-322, which authorized the Department of the Interior to spend up to $2.9 million for the three-year pilot project to investigate the feasibility of nutria eradication in Maryland. The pilot project began on January 1, 2000 and ended in December 2002.

On February 3, 1999, President Clinton signed Executive Order 13112 to control invasive species and to minimize the economic, ecological, and human health impacts that invasive species cause to agricultural crops and natural ecosystems. In 1999, the partners were also successful in obtaining a Capacity Building Grant from the U.S. Department of Agriculture (USDA) of almost $300,000 for a portion of the research component of the nutria plan. In the fiscal year 2000 budget, Congress directed the USFWS to allocate $500,000 from its budget specifically to support the first year of the pilot program. To implement the first year of the three-year pilot program at a reduced scale, the partners agreed to combine these resources (approximately $800,000).

In April 2002, the eradication phase was fully implemented with the formation of the Chesapeake Bay Nutria Eradication Project (CBNEP). The USDA Animal and Plant Health Inspection Service (APHIS) - Wildlife Services, assumed primary responsibility for project implementation. Without this concerted partnership effort, nutria would continue to destroy wetlands throughout the region. Recognizing this concern, President Bush signed the Nutria Eradication and Control Act of 2003, which authorized the expenditure of $4 million per year for five years to eradicate Nutria from the Chesapeake and Delaware Bays.

Before Nutria Removal (left). After Nutria Removal (right).
Before Nutria. After Nutria.

The CBNEP has since expanded its eradication program far beyond the original efforts at Blackwater National Wildlife Refuge. Currently over a quarter million acres of the previously nutria infested, Delmarva Eastern Shore marshes and wetlands are nutria free, and the project is now in its final phase of confirming total eradication. That requires that CBNEP staff revisit previously trapped watersheds multiple times over several years to detect and remove any nutria that were not previously found. This is what is referred to as the “mop-up and verification” phase of eradication and that is where the project has progressed as of 2016.

The CBNEP is overseen by the Nutria Management Team, consisting of representatives from the USFWS’s Chesapeake Bay Field Office, Chesapeake Marshlands National Wildlife Refuge Complex, USDA APHIS Wildlife Services, MD DNR, Delaware Department of Natural resources and Environmental Control, and Virginia Department of Game and Inland Fisheries.

In addition to the Nutria Management Team, the Chesapeake Bay Nutria Eradication Partnership is supported by a coalition of 25 private, local, state, and federal partners that is critical to the success of the nutria eradication project. The partners work together to obtain necessary financial and other types of support for project operations.

Visit our Project Partners page to contact members of this project.

Last updated: March 9, 2016