New England MarineMarine InvaderInvader IDID Card Card CrabsCrabs

Arjan Gittenberger WikiCommons Cristina Kennedy Arjan Gittenberger Carcinus maenas Hemigrapsus sanguineus European Green Asian Shore Crab • Typically dark green or green-yellow with dark mottling, but • Oen orange-brown, also olive green, maroon, or purple with sometimes dark brown or red light and dark bands on legs • Carapace up to 3.5 inches wide with five spines on each side and • Square-shaped carapace up to 2 inches wide with three spines on three spines between eyes each side and no spines between eyes • Common in sheltered coastal habitats, including estuaries, salt • Common in the intertidal, tolerant of a wide range of salinities marshes, sandy beaches, and rocky shores and temperatures • Native to the coasts of Europe and North Africa, first observed in • Native to the north Pacific coasts of Asia, first observed in New New England in the mid-1800s England in the 1990s • May reduce shellfish abundance, destabilize creek banks in salt marshes, and disturb eelgrass beds

To differentiate the region’s , it is helpful to take careful note of the shape of the carapace (the shell containing the body of the crab) and the number of spines on each side of the eyes. See the back of this card for an illustration of the carapaces of select . Both C. maenas and H. sanguineus occur throughout New England.

Marine Invader Monitoring and MASSACHUSETTS OFFICE OF Information Collaborative (MIMIC) Established Invaders COASTAL ZONE MANAGEMENT Similar Species

Maria Conchita Adrienne Pappal Arjan Gittenberger Cristina Kennedy spp. Family Blue Crab Jonah and Atlantic Rock Crabs Mud Crabs • Green-blue with long front legs and • C. borealis (Jonah Crab, le) and C. irroratus (Rock Crab, right) • Dark to light brown with large, large, slender blue claws are reddish brown or light purple with nine spines on each side dark-tipped claws, three • Distinct flared carapace up to 9 of their carapace spines on sides of carapace inches wide with a long last spine • Both can grow to a large size (carapace up to 5 inches wide), • Small (carapace width up to • Swimming crab with paddle-like especially in deeper waters 1.5 inches) hind legs • C. borealis has bumpy spines, C. irroratus has smooth spines • Common in muddy habitat • More abundant south of Cape Cod, • Both are found in intertidal to deeper waters throughout New and on docks becoming more common north England • Close inspection is required to distinguish between the Carapaces of Select Crabs of the New England Coast common mud crab species Carcinus maenas Hemigrapsus sanguineus herbstii in New England, including European Green Crab Asian Shore Crab Rock Crab Atlantic Mud Crab sayi (Say Mud (5 spines) (3 spines) (9 spines) (3 spines) Crab) and (Atlantic Mud Crab)

Species are all native.