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Mitten crab (Eriocheir sinensis)
Credit: Christian Fischer
Chinese Mitten Crab
Eriocheir sinensis

• Between 2005-2008, 19 individuals were confirmed along the U.S. Atlantic coast in the Chesapeake Bay (2005-2007), Delaware Bay (2007), Hudson River (2007-2008), and Raritan Bay and Toms River, New Jersey (2008)
• In Quebec, specimens have been collected from St. Lawrence River at Notre-Dame-de-Pierreville in 2004 and Quebec City in 2005
• Both females and males have been found, but an established reproductive population in eastern U.S. has not been confirmed as of the summer of 2008

• Light brown to olive green
• Carapace (shell) up to 4 in (10 cm) wide
• 4 lateral spines on each side of carapace
• Notch between the eyes
• Claws hairy with white tips
• Claws normally equal in size
• Legs longer than twice the carapace width

• Estuaries, lakes, riparian zones, water courses, wetlands
• Burrows in the bottom and banks of freshwater rivers and estuaries
• Tolerates wide range of temperatures
• Catadromous life cycle: begins as estuarine larva, migrates into
freshwater streams for 1-4 years, then returns to coast to reproduce
• Able to survive in highly polluted aquatic habitats
• Adept at walking on land and around barriers

Known Distribution:
• Native to east Asia
• Chesapeake Bay, Delaware Bay, Hudson River, New Jersey, Quebec

• Efficient predator and competitor for foodl; may have a profound effect on native biological communities
• Damage to fishing gear
• Clogged pumps, screens, and intake pipes
• Burrowing activity may accelerate erosion of banks and levees

Common Vector(s):
Shipping: Ballast water