Preventing new nonnative and invasive species from becoming established in marine waters has long been a challenge, and the difficulty and cost of erradicating established nonnative species is well documented. Fortunately, we do not yet have documented populations of the invasive Chinese mitten crab, Eriocheir sinensis, in the Gulf of Maine, but it has been advancing steadily toward our coastal waters. A native of Korea and China, the mitten crab was first identified on the eastern seaboard in the Chesapeake Bay and has since spread north to the Delaware and Hudson River systems. The crabs are catadromous, meaning they spend much of their adult lives in freshwater, and migrate to salt water to reproduce, so they can be found throughout coastal watersheds. Potential impacts of the large crabs (up to 12 inches in diameter, including legs) include burrows in estuarine sediments that cause costly erosion, predation on and competition with other marine and estuarine species, and interference with commercial fishing gear.
Northeast Sea Grant Programs are working to coordinate the efforts of citizens and non-profit organizations already monitoring coastal waters for invasive species, with state agencies and other professionals in an early detection network that will document and remove live mitten crabs and work to prevent new introductions to the Gulf of Maine. Preliminary analysis of estuarine habitat data will help to focus citizen scientist monitoring efforts in areas most vulnerable to invasion, and Northeast Sea Grant staff are working in concert with the Northeast Aquatic Nuisance Species Panel and state agency personnel to prepare a Northeast Rapid Response Plan for the region.
This project is funded through a $240,000 National Strategic Investment in research and outreach related to Aquatic Nuisance Species by the NOAA National Sea Grant Program. The three-year project will conclude in Fall 2015.
Alyson Eberhardt, Ph.D.
Coastal Ecosystems Extension Specialist
Rapid Response Plan PDF:
Chinese mitten crab watch card: