Invasion
Invasion Description
1st record: "Atlantic Coast of the United States" (MD or NJ, Say 1817)
Geographic Extent
Eastham/MA/Nauset Marsh (2003, de Rivera et al. 2005); Chatham/MA/Atlatnic Ocean (1904, MCZ 62319, Museum of Comparative Zoology 2009); Falmouth/MA/Waquoit Bay (2003, de Rivera et al. 2005); MA/Waquoit Bay (1903, MCZ 7436, Museum of Comparative Zoology 2009); Marthas Vineyard/MA/Vineyard Sound (Verrill and Smith 1873); Woods Hole/MA/Vineyard Sound-Buzzards Bay (Verrill and Smith 1873); MA/"various connecting ponds and estuaries"; Woods Hole/MA/Eel Pond (Vineyard Sound) (Verrill and Smith 1873); Tripp Marina, Westport/MA/Westport River (Buzzards Bay) (MIT Sea Grant 2002); New Bedford/MA/Buzzards Bay (MIT Sea Grant 2002); New Bedford/MA/Buzzards Bay (MCZ 5411, Museum of Comparative Zoology 2009); Massachusetts Maritime Academy Bourne/MA/Buzzards Bay (MIT Sea Grant 2002); India Point, Providence/RI/Providence River (2000, MIT Sea Grant 2003); Warwick Cove Marina/RI/Warwick Cove, Narragansett Bay (2000, MIT Sea Grant 2003); Roger Williams University, Bristol/RI/Mount Hope Bay (2000, MIT Sea Grant 2003); Prudence Island/RI/Potters Cove (2000, MIT Sea Grant 2003); North Kingstown/RI/Allens Harbor (2000, MIT Sea Grant 2003); Wickford Marina/RI/Wickford Harbor, Narragansett Bay (2000, MIT Sea Grant 2003); Newport/RI/Rhode Island Sound; Fort Getty, Jamestown/RI/Narragansett Bay (2000, MIT Sea Grant 2003); Point Judith/RI/Rhode Island Sound (1851, Leidy 1855); Washington Co./RI/Point Judith Pond (2003, de Rivera et al. 2005); "Long Island" (Rafinesque 1817); Brewer Yacht Yard, Mystic/CT/Fishers Island Sound (2003, MIT Sea Grant 2003); Milford Yacht Club, Milford/CT/Long Island Sound (2003, MIT Sea Grant 2003); Stirling Harbor Shipyard, Brewer Yacht Haven Marine Center, Stamford/CT/Long Island Sound (2003, MIT Sea Grant 2003); Greenport/NY/Peconic Bay (2003, MIT Sea Grant 2003); Fire Island/NY/Great South Bay (1882, Rathbun 1930); NJ/'Bays and Inlets' (Little Egg Harbor (1817, Say 1817); Great Kills Park, Staten Island/NY/New York Harbor (2003, MIT Sea Grant 2003); NJ/Barnegat Bay (1973, Loveland and Voughliotis 1984); NJ/Barnegat Inlet (1972, Peterson 1979); NJ/"Bays and Inlets" (Little Egg Harbor", Say 1817); NJ/Great Bay (2003, DeRivera et al. 2005); Somers Point/NJ/Atlantic Ocean (~1853, MCZ 5412, Museum of Comparative Zoology 2009, collected by W. Stimpson); Cape May/NJ/Delaware Bay (1900, Rathbun 1930); (2002, de Rivera et al. 2005); Lewes/DE/Delaware Bay (Leathem and Maurer 1980); DE/Indian River Inlet (2003, Miller and Brown 2005); Worcester County/MD/Sinepuxent Bay (2003, de Rivera et al. 2005); MD/Chincoteague Bay; Ocean City/MD/Atlantic Ocean (1995, Hines, personal communication); Worcester County/MD/Sinepuxent Bay (2003, de Rivera et al. 2005); Northampton Co./VA/Hog Island Bay (1876, Kingsley 1879, not established); Somerset County/upper Manokin River (6-25-2007, Kevin Josenhans, MD DNR, personal communication, Lat 38.07.986' N, Long 075.47.899' W, 1 specimen); Save the Bay Docks, Providence/RI/Providence River-Great Kills Marina, Staten Island/NY/New York Bight (2019, Pederson et al. 2021, 3 of 10 sites surveyed)
Vectors
| Level | Vector |
|---|---|
| Probable | Hull Fouling |
| Alternate | Dry Ballast |
Regional Impacts
| Ecological Impact | Predation | |
| Carcinus maenas is a major predator on bivalves in Buzzards Bay-Vineyard Sound, Narragansett Bay and Long Island Sound. Field observations indicate that the abundance of C. maenas and its spread into estuaries decreases south of Long Island (de Rivera et al. 2005b). Carcinus maenas is a major predator in invertebrate communities in Buzzards Bay and Vineyard Sound. Studies of its effects on Mercenaria mercenaria (Quahaug; Hard Clam) populations in coastal lagoons ("salt ponds") on Martha's Vineyard indicate that C. maenas is a major source of mortality to clam populations. Evidence for this includes caging (predator exclusion) and massive removal experiments (Walton et al. 1999; Walton and Walton 2001; Walton et al. 2002). In the Narragansett Bay region, gut content studies indicate that Mytilus edulis was the predominant food of adult C. maenas in the Pettaquamscutt River estuary, while juveniles fed mostly on small crustaceans (Ropes 1989). In field experiments at Avery Point, Long Island Sound, C. maenas fed on young mussels at a higher rate than the recently introduced crab, Hemigrapsus sanguineus (Asian Shore Crab), but the much higher densities of H. sanguineus now make it the more important predator in the rocky intertidal (Lohrer and Whitlach 2002). Predation by adult Carcinus on juvenile Argopecten irradians (Bay Scallop) in Long Island Sound was studied experimentally in laboratory experiments. Carcinus were one of several predators responsible for mortality of young scallops in field tethering experiments, but juvenile mud crabs were considered to be the most important predators, because of their ability to climb eelgrass blades where young Argopecten were attached (Pohle et al. 1991). Taylor (2005) found that Green Crabs in Long Island Sound had a small predatory impact (1-8% of daily mortality) on newly settled juveniles of the Winter Flounder (Pseudopleuronectes americanus). | ||
| Economic Impact | Fisheries | |
| Carcinus maenas is a major predator of commercial shellfish in Buzzards Bay-Vineyard Sound, Narragansett Bay and Long Island Sound (Walton et al. 1999), but its abundance and commercial importance appears to decrease sharply in the southern half of its range (de Rivera et al. 2005b). Carcinus maenas is a major predator on commercial shellfish in Buzzards Bay and Vineyard Sound. Studies of its effects on Mercenaria mercenaria (Quohaug; Hard Clam) populations in coastal lagoons ("salt ponds") on Martha's Vineyard indicate that C. maenas is a major source of mortality to clam populations. Evidence for this includes caging (predator exclusion) and massive removal experiments (Walton et al. 1999; Walton and Walton 2001). This species is well-known as a shellfish pest here. Carcinus maenas preys on bivalves in Long Island Sound. Predation by adult Carcinus on juvenile Argopecten irradians (Bay Scallop) was studied experimentally in laboratory experiments. Carcinus was one of several predators responsible for mortality of young scallops in field tethering experiments, but juvenile mud crabs were considered to be the most important predators, because of their ability to climb eelgrass blades where young Argopecten were attached (Pohle et al. 1991). Intense predation by green crabs on adult scallops has been observed in Connecticut waters (Morgan et al. 1980, cited by Pohle et al. 1991). Carcinus maenas is locally regarded as a serious predator of commercial shellfish (Ropes 1989). It is locally caught and sold as bait for fishing. | ||
| Ecological Impact | Competition | |
| In laboratory trials, C. maenas frequently outcompeted Callinectes sapidus of equal size for food and won fights over food more frequently than C. sapidus or Hemigrapsus sanguineus (MacDonald et al. 2007). However, predation by adult C. sapidus may be limiting the southern range expansion of C. maenas (de Rivera et al. 2005b). | ||