Invasion History

First Non-native North American Tidal Record: 1817
First Non-native West Coast Tidal Record: 1990
First Non-native East/Gulf Coast Tidal Record: 1817

General Invasion History:

Carcinus maenas, also known as the Green Crab, is native to European Coasts from Iceland and Norway to Mauritania, West Africa. It has invaded six major regions, the Northwest Atlantic (from Maryland-Newfoundland), the Southwest Atlantic (Patagonia), the Southeast Atlantic (South Africa), the Northeast Pacific (from California-Alaska), the Northwest Pacific (Japan) and the Southwest Pacific (Australia) (Cohen et al. 1995; Carlton and Cohen 2003).

North American Invasion History:

Invasion History on the West Coast:

In 1989, a single Carcinus maenas was collected at Estero Americano, near Bodega Harbor, California. This may have been an isolated introduction (Grosholz and Ruiz 1995). In 1990, a specimen was caught at Redwood City, on South San Francisco Bay (Cohen et al. 1995). By 1993, C. maenas was abundant throughout the Bay (Cohen et al. 1995) and by 1994 it was found from San Francisco Bay north to Bodega Harbour (120 km) (Grosholz and Ruiz 1995). In 1997, C. maenas was collected in Coos Bay, Oregon, in 1998 it was collected in Willapa Bay, Washington, and in 1998, in Barkley Sound, British Columbia (Grozholz and Ruiz 1996; Washington Department of Fish and Wildlife 1997; Fisheries and Oceans Canada 1998). In 2007, its northern limit was Winter Harbour, Quatsino Inlet, on the west coast of Vancouver Island (50.5330 N, Klassen and Locke 2007)..Populations in Barkley Sound show indications of rapid individual growth, characteristic of an expanding population (McGaw et al. 2011). In 2020, Green Crabs were collected in Haida Gwai (Qu  (Queen Charlotte Islands, 53.1 Nº and in 2021, in Ketchikan, Alaska (Miller 2022).  Recruitment in the Oregon-Washington part of the range has been sporadic, depending on favorable currents and warmer water temperatures in 2003, 2005, 2006 and 2010, influenced by the Pacific Decadal Oscillation, and the El Niño Southern Oscillation (Yamada et al. 2015). Expansion into the Strait of Georgia and Puget Sound has  been slow, In 2016-2021, specimens were collected in the San Juan Island/s. Padilla Bay, Dungeness Spit  and Lummi Seafood Hatchery Bay (Yamada et al. 2017, University of Washington 2017; Associated Press 2021). 1n May 2022, one specimen was collected in the Hood Canal;, part of Puget Sound proper (US Geological Survey Nonindigenous Species Database 2022). Establishment in Puget Sound is likely (Carolyn Tepolt, personal communication 2022),  Southward dispersal has been much slower, with C. maenas spreading only to Monterey Bay and Elkhorn Slough in 1993 (Grosholz and Ruiz 1995; Ruiz et al. unpublished data) and Morro Bay in 1998, the current southern limit (USGS Nonindigenous Species Program 2009). Genetic studies indicate that the West Coast populations of C. maenas originated from the East Coast (Bagley and Geller 2000; Tepolt et al. 2009; Darling 2011). The Green Crab was likely introduced to the West Coast through the live-bait trade, or less likely, in the ballast water of ships (Cohen et al. 1995; Grosholz and Ruiz 1995). Surveys in northern California (Bodega Harbor, Bolinas Lagoon, Tomales Bay) suggest that predation by native crabs (Cancer and Metacarcinus spp.) may limit the establishment of this crab to low-salinity habitats (Jensen et al. 2007). Genetic studies suggest that the rapid spread of Green Crabs across 12 degrees of latitude in 10 years, despite low genetic diversity.  Tepolt et al. (2021) suggested that a cluster of genes, in s chromosomal inversion permitted local temperature adaptation despiite rapid overall gene flow,

Invasion History on the East Coast:

One of the first records of Carcinus maenas from the Atlantic Coast was Say (1817), as Cancer granulosus: 'Inhabits bays and inlets near the sea'. Thomas Say is known to have collected on the Atlantic coasts of Maryland and New Jersey, so C. maenas apparently first colonized the Mid-Atlantic region, and spread north of Cape Cod in the late 19th century.

Carcinus maenas was collected by Say (1817) on the Atlantic Coast, probably in New Jersey, but possibly from the Atlantic coast of Maryland. It was also reported, as Portunus maenoides from Long Island, in 1817 (Rafinesque 1817). Other early records are from Martha’s Vineyard, Massachusetts (Gould 1841), Long Island Sound, New York, and Newport, Rhode Island (DeKay 1844). Before 1911, it was abundant at Atlantic City, New Jersey (Fowler 1911). Carcinus maenas was collected at Cape May, New Jersey by 1900 (Almaca 1963). 'Carcinus maenas, the green crab, is not common in Delaware Bay, and has only been collected by us from the Cape Henlopen tidal flat... and from the southernmost tributary entering Delaware Bay' (Leathem and Maurer 1980). Larvae were reported in plankton by Deevey 1960 (cited by Williams 1984). On the Atlantic coast of the Delmarva Peninsula, Carcinus maenas was collected in 1874 in Hog Island Bay, in Northampton Co., Virginia: 'a single male... This is the farthest south on the Atlantic coast of the United States from which this species has been reported' (Kingsley 1879). In recent surveys, this crab was found from Delaware to Virginia, in Indian River, Assawoman, Sinepuxent and Chincoteague Bays (in 2003, de Rivera et al. 2005a; Miller and Brown 2005). In 2007, a Green Crab was caught in Chesapeake Bay, in the upper Manokin River, Somerset County (Kevin Josenhans, Maryland DNR, personal communication). 

From the Gulf of Maine northwards- Carcinus maenas was collected in Provincetown, Massachusetss in 1905, and successively spread to Casco Bay, Maine in 1922-1930; Penobscot Bay (Rockland, Bar Harbor), Maine in 1951-1953; and Passamaquoddy Bay (Maine to New Brunswick Canada) and the Bay of Fundy, Nova Scotia, in 1953 (Almaca 1963; Vermeij 1982b). Contrary to some published reports, C. maenas was not collected in the Gulf of St. Lawrence until 1994, but it is now found on both the Nova Scotia and Prince Edward Island sides of Northumberland Straits, and on the north side of Prince Edward Island (Audet et al. 2003). By 1991, it crossed the Straits of Canso onto Cape Breton Island, Nova Scotia (Audet et al. 2003), and has colonized the Bras d'Or Lakes on the island (Cameron and Metaxas 2005). In 2007, C. maenas was discovered in Placentia Bay, Newfoundland (Canadian Broadcasting Company News 2007; Klassen and Locke 2007; Blakeslee et al. 2010). The expansion from Nova Scotia into the Gulf of St. Lawrence involved an introduction of genetically distinct crabs, probably of Scandinavian origin (Roman 2006; Blakeslee et al. 2010; Darling 2011). Genotypes from this second introduction are transported by currents and are appearing in populations in the Gulf of Maine (Pringle et al. 2011; Darling et al. 2014; Williams et al. 2015). The two genotypes are hybridizing in Nova Scotia and Newfoundland, but the impacts of this introgression on the crab's temperature tolerances are unknown (Jeffery et al. 2017).

In recent decades (1990s to the present), Carcinus maenas has been partially displaced from rocky shore areas, from New Jersey to Massachusetts Bay by Hemigrapsus sanguineus (Asian Shore Crab) through competition and predation on juveniles (Lohrer and Whitlatch 2002; Griffen and Delaney 2007; Griffen 2011). Carcinus maenas has been observed to move into rocky-intertidal areas at high tide, presumably from subtidal regions, or from hiding places under boulders (James Carlton, personal communication). Carcinus maenas remains common in soft-bottom habitats where H. sanguineus is absent.

Invasion History in Hawaii:

In 1873, Carcinus maenas was collected in the Hawaiian Islands (Street 1877, cited by Carlton and Cohen 2003). There are no further records from Hawaii.

Invasion History Elsewhere in the World:

In the Northwest Pacific, Carcinus spp. were recorded at Tokyo Bay in 1984. The date erroneously was given as 1958 by Sakai 1986 (cited by Carlton and Cohen 2003). Both Carcinus aestuarii (from the Mediterranean) and Carcinus maenas are present in Japan. DNA data from Bagley and Geller (2000) suggest that there was a single source population which included both species, possibly from the Iberian Peninsula, where the two species overlap (Carlton and Cohen 2003; Darling 2011). In 1999, Carcinus spp. was present in Sagami and Osaka Bays in Honshu and Dokai Bay in Kyushu, Japan (Carlton and Cohen 2003). In the Southwest Pacific, the Green Crab is established in Australia. Although regular records from New South Wales start in the 1970s, Ahyong (2005) suggests that C. maenas was established, but overlooked or misidentified, in the Sydney area since the late 19th century. In 1900, C. maenas was collected in Port Phillip Bay, Victoria (Fulton and Grant 1900), and by 1998 had spread along much of the coast of Victoria (Thresher et al. 2003). In 1993, this crab was collected on the north shore of Tasmania, and by 1998, was found in many harbors on the north and east coasts of the island. In 1976, C. maenas was collected in Adelaide Harbour, South Australia, and is established there (Furlani 1996; Thresher et al. 2003). It has not, however, become established in Western Australia's major port, Perth, where it was collected in 1965 (Furlani 1996).

In the Southern Atlantic, Carcinus spp. was collected at Table Bay Docks, Cape Town, South Africa in 1983. By 1990, Carcinus spp. ranged from Camps Bay to Cape Saldanha, a distance of 200 km (Griffiths et al. 1992). However, C. maenas failed to become established in Saldanha Bay, so that the current range is limited to Cape Town Bay and its enclosing peninsula (Robinson et al. 2005). Samples included a mix of C. maenas and C. aestuarii genotypes (Geller et al. 1997). In the Southwest Atlantic, C. maenas was collected in 2003 from Camerones Bay, Chubut Province, Patagonia, Argentina, where it is established (Hidalgo et al. 2005). Genetic studies indicate that Argentine populations were introduced from Australia (Darling 2011).

In additon to its six major established populations, Carcinus spp. (probably mostly C. maenas, but could include C. aestuarii) have been collected from many sites around the world, mostly in the tropics, where it has failed to become established, or its establishment is unknown. These sites include the Azores (Drouet 1861; Sampaio 1904, cited by Morton and Britton 2000), Rio de Janeiro and Pernambuco, Brazil (in 1857 and 1899, Carlton and Cohen 2003), the Pacific coast of Panama (in 1866, Carlton and Cohen 2003), Myanmar (Burma) (in 1933, Carlton and Cohen 2003), Ceylon (Sri Lanka) (in 1886, Carlton and Cohen 2003), Pakistan (in 1971, Carlton and Cohen 2003), the Red Sea (in 1817, Carlton and Cohen 2003), and Madagascar (in 1922, Carlton and Cohen 2003). The failure to become established in these warm waters is probably related to temperature tolerances of adult and larval stages.


Description

The carapace of Carcinus maenas is about 3/4 long as it is broad, with a surface finely and unevenly granular, especially in the anterior half. The front has three round lobes or teeth projecting moderately between its eyes. The anterior-lateral border is slightly arched with five strong teeth, directed forward, on each side. The claws are slightly unequal, nearly smooth except for two ridges on the upper surface of the hand. The merus ('forearm') is short, while the carpus ('wrist') has a broad internal tooth or angle. The walking legs are smooth and spineless. The fifth pair of legs is slightly flattened, but is not greatly modified for swimming. The abdomen of male C. maenas is broad and triangular, with segments 3-5 fused. The mature female has a broad abdomen, with free segments. The color is highly variable, but adults are usually multicolored with a dorsal surface ranging from dark green, grayish green, or reddish, while the undersurface is yellowish white to orange. In juveniles, the color is highly variable, often with bold contrasting colors (Williams 1984).

Zoeae and megalopae larvae of C. maenas are illustrated in Roft et al. (1984) and Johnson and Allen (2005), along with additional references on larval development, and comparisons to East Coast crab larvae. Rice and Tsukimura (2007) also provide a description, with comparisons to West Coast (San Francisco Bay) crab larvae.


Taxonomy

Taxonomic Tree

Kingdom:   Animalia
Phylum:   Arthropoda
Subphylum:   Crustacea
Class:   Malacostraca
Subclass:   Eumalacostraca
Superorder:   Eucarida
Order:   Decapoda
Suborder:   Pleocyemata
Infraorder:   Brachyura
Superfamily:   Portunoidea
Family:   Portunidae
Genus:   Carcinus
Species:   maenas

Synonyms

Cancer granulatus (Say, 1817)
Cancer moenas (De Kay, 1842)
Carcinides maenas (Rathbun, 1930)
Carcinus granulatus (Smith, 1873)
Portunus maenoides (Rafinesque, 1817)

Potentially Misidentified Species

Carcinus aestuarii
The status of the Mediterranean Green Crab, C. aestuarii Nardo 1847 (C. mediterraneus Cziernavsky 1884), as a separate species from C. maenas, has been disputed. Morphological differences between the two species include subtle differences in shapes of spines and segments, the shape of the frontal carapace, male pleopod shape, number of segments in the flagellum, and presence/absence of setae on the chelipeds. A morphometric study by Clark et al. (2001) found some overlap between the two populations. However, Yamada and Hauck (2001) listed morphological characteristics for field separation of the two species and they found an intermediate specimen from Rabat, Morocco. Genetic studies by Bagley and Geller (2000) and Roman and Palumbi (2004) support the separation of the two species.

Ecology

General:

Life History- In crabs of the family Portunidae, the male attends the female before molting, and carries the female around, underneath his carapace. He releases the female, allows her to molt, and then copulates with her, inserting the first pair of pleopods, carrying sperm, into the female's seminal receptacles. The eggs are fertilized internally, and then extruded as a 'sponge' or a mass of eggs brooded between the abdomen and the body (Crothers 1968; Barnes 1983; Williams 1984). The number of eggs varies with size of the crab, but typical number of eggs for Carcinus maenas are around 185,000-200,000 (Broekhuysen 1936; Crothers 1966; Berrill 1982). The eggs hatch into zoea, larvae about 1 mm long, armed with long spines, which drift in the plankton. Each zoea goes through six molts, and eventually molts into a post-larval megalopa, with prominent eyes and partially developed appendages. The megalopa is capable of crawling on the bottom and active, directed swimming. After 25 to 90 days from hatching, depending on temperature and food availability, it settles and molts into a miniature 'first crab' which has all the features of an adult crab (Crothers 1968; Barnes 1983; Leignel et al. 2014).

Ecology- Carcinus maenas is most abundant in intertidal and shallow subtidal habitats through most of its range. It is more abundant in shallow, protected bays than on exposed shores (Williams 1984). In the Isles of Shoals, Gulf of Maine, Carcinus maenas is most abundant in the intertidal, while the larger Cancer irroratus (Rock Crab) and C. borealis (Jonah Crab) are most abundant in the subtidal (Donahue et al. 2009). In New South Wales, Australia, C. maenas colonized lagoons that were open to the sea > 60% of the time, and were more abundant in mangroves than in marsh or seagrass habitats (Garside et al. 2014). Fish predation may be a major factor limiting C. maenas in subtidal waters (Donahue et al. 2009).  Green crabs are omnivorous, but their diet ends to be dominated by invetebrates, espeically mollusks, crustaceans, and annelids.  Algae are usually a minor componet of the diet. (Corothers 1968;; Ropes 1989; LeRoux et al. 1990;  Rossong et al. 2011; Wong and Dowd 2014; Quinn and Boudreax 2016; Cornelius,et al. 2021; Corodone et al. 2022

Food:

molluscs; crustaceans; other inverts; algae

Consumers:

Crabs; Lobsters; Fishes, Birds

Competitors:

Trophic Status:

Omnivore

Omni

Habitats

General HabitatUnstructured BottomNone
General HabitatGrass BedNone
General HabitatMarinas & DocksNone
General HabitatRockyNone
General HabitatSalt-brackish marshNone
General HabitatCoarse Woody DebrisNone
General HabitatOyster ReefNone
Salinity RangeMesohaline5-18 PSU
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeSubtidalNone
Tidal RangeLow IntertidalNone
Tidal RangeMid IntertidalNone
Tidal RangeHigh IntertidalNone
Vertical HabitatEpibenthicNone

Life History


Tolerances and Life History Parameters

Minimum Temperature (ºC)-1None
Maximum Temperature (ºC)35Experimental, Critical Temperature Maximum (CTM, rapid gradual temperatyre ncrease) varies from 32-36 C, with season and acclimation temperature (Leignel et al. 2014).Temperature Range- Equatorward distribution limited by average summer surface temperature of ~22C (Cohen et al. 1995).
Minimum Salinity (‰)4Salinity Range- Found in flooded tidepools in salinities as low as 1.4 ppt. 10 ppt is a more usual lower limit (Williams 1984). Larvae require at least 17-19 ppt to metamorphose and settle (Rasmussen 1973, cited by Williams 1984).
Maximum Salinity (‰)54Broekhuysen 1936, Experimental. Elevated salinities are possilbe in isolated tidepools, under a hot sun.
Minimum Reproductive Temperature6Ovigerous females, 6-10 C, Placentia Bay, Newfoundland (Best et al. 2017)
Maximum Reproductive Temperature17Williams 1984
Minimum Reproductive Salinity13Broekhuysen 1936
Maximum Reproductive Salinity54Broekhuysen 1936
Minimum Duration25Release to first crab- Berrill 1982; Lipski, unpublished data
Maximum Duration90Release to first crab- Berrill 1982; Lipski, unpublished data
Minimum Length (mm)19For adult female, 25 mm for males. Broekhuysen 1936; Crothers 1967, Crothers 1968; Berrill 1982
Maximum Length (mm)86For adult male, 70 mm for females, Broekhuysen 1936; Crothers 1967, Crothers 1968; Berrill 1982

General Impacts

Carcinus maenas, also known as the Green Crab, has been listed by the Invasive Species Specialist Group of the World Conservation Union (IUCN) as one of the '100 worst invasive species.'

Economic Impacts:

Fisheries- Carcinus maenas had a major impact on shellfisheries in New England, and may have similar effects on fisheries on the West Coast of North America and Australia. Predation by Green Crabs led to a reduction in Mya arenaria (Soft-Shell Clam) harvests in Maine in the 1940s-1950s (Dow and Wallace 1952). It is also a major predator on Mercenaria mercenaria (Quahog or Hard Clam) in southern New England (Walton et al. 2001). Other commercial shellfish eaten by Green Crabs in New England include blue mussels, the oyster Crassostrea virginica (Miron et al. 2005; Breen and Metaxas 2009) and Bay Scallops (Pohle et al. 1991). On the West Coast, Carcinus maenas is regarded as a potential predator on commercially important clams, including introduced Softshell Clams, Japanese Littlenecks (Venerupis philippinarum), and the Mediterranean Mussel (Mytilus galloprovincialis), as well as the native Pacific Littleneck (Leukoma staminea) (Grosholz et al. 2011). Predation by Carcinus maenas was predicted to adversely affect the fishery for the clam Katelysia scalarina in Tasmania (Walton et al. 2002). Shellfishermen use mesh bags, cultivation on ropes and in cages, to minimize predation, and may use traps to remove crabs (Walton et al. 1999; Grosholz et al. 2001). Planting large seed clams, or altering the timing of planting may also reduce losses due to Green Crab predation (Grosholz et al. 2001). Estimated current losses of bivalve fisheries (Pacific Littleneck, Japanese Littleneck, Softshell Clam, Blue Mussel) in California are negligable, but with future population increases could reach $20,000-60,000 per year (Grosholz et al. 2011).

Predation on juveniles of larger harvested crustaceans, such as American Lobster (Homarus americanus) on the East Coast (Rossong et al. 2006) and Dungeness Crab (Metacarcinus magister) on the West Coast (Cohen et al. 1995) is also a concern. However, Green Crabs are also frequent prey for large crabs and lobsters (Lynch and Rochette 2009), so impacts of the C. maenas invasion on these fisheries are difficult to determine.

In Europe, where it is native, C. maenas has long been used for food, but it is rarely caught or eaten in the United States (Williams 1984). In the US, it is widely shipped and sold as bait (Grosholz and Ruiz 1996). In Maryland and elsewhere, fishermen are encouraged to kill unused bait crabs, rather than release them, by signs posted by state agencies at fishing locations (Paul Fofonoff, personal observation).

Ecological Impacts:

Predation- On the East and West coasts of North America, and in Australia Carcinus maenas has had serious impacts on shore communities; primarily as one of the chief predators of the intertidal zone. It can affect the survival and recruitment of gastropods, bivalves, other crabs, and probably a wide range of other invertebrates (Vermeij 1982a; Vermeij 1982b; Williams 1984; Grosholz and Ruiz 2002). It is a major predator of Mya arenaria (Soft-Shell Clams) in the Gulf of Maine (Dow and Wallace 1952). In cage experiments on a mudflat in Pomquet Harbour, Nova Scotia, Carcinus maenas removed 80% of small Softshell Clams (Mya arenaria) but had negligible impacts on larger clams (Floyd and Williams 2004). In Tasmania, abundance of Carcinus maenas was negatively correlated with that of the native venerid clams Katelysia scalarina, K. rhytiphora, and Fulvia tenuicostata (Walton et al. 2002; Ross et al. 2004). On the Pacific coast, C. maenas has significantly reduced densities of the most abundant benthic taxa in Bodega Bay, California (Grosholz and Ruiz 2002).

Impacts of C. maenas's invasions are complicated by the fact that native crab species are present, and other crab species can invade, functioning as prey, competitors, and/or predators of Green Crabs. Consequently, it is necessary to compare patterns and rates of C. maenas predation to that of other crabs. In Tasmania, caging experiments showed that predation rates of C. maenas greatly exceeded those of native crabs or other predators (Walton et al. 2002). On the Oregon coast, C. maenas fed on native mussels (Mytilus trossulus) at lower rates than the native Metacarcinus magister (Dungeness Crab), but were more efficient than equal-sized Cancer magister at feeding on native Olympia Oysters, Ostrea lurida, because of greater claw strength (Yamada and Kosro 2010). In the Bras d'Or Lakes, Nova Scotia, Breen and Metaxas (2009) measured predation rates of juvenile and adult C. maenas on mussels (Mytilus sp.) and compared them to two species of native crabs Cancer irroratus (Rock Crab) and Dyspanopeus sayi (Say's Mud Crab). Rates of mussel consumption by C. maenas were similar or lower than those of the native species, but a favorable year for recruitment could increase the crabs' impact (Breen and Metaxas 2009). 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 south of Cape Cod (Lohrer and Whitlach 2002).

Interactions among crabs of different sizes often result in predation, either among crabs of the same species or different species. Over an 11-year period in Bodega Harbor, Hemigrapsus oregonensis abundance was negatively correlated with C. maenas abundance, but recovered, with a lag period, when C. maenas declined (de Rivera et al. 2011). Large C. maenas prey on small H. sanguineus and vice versa (Griffen and Byers 2009). Predation, aggression, and interference behavior have the effect of reducing the predation rates of both species when they co-occur. In laboratory experiments, Carcinus maenas was found to consume juvenile lobsters in 6 of 11 trials (Rossong et al. 2006). Further, very small lobsters (under 35 mm carapace length) showed reduced foraging in the presence of Green Crabs. However, field studies and laboratory experiments indicate that rates of predation are low, and that predation on C. maenas by lobsters may be equally or more frequent (Lynch and Rochette 2009).

The invasion of a new predator, such as C. maenas, can also alter the behavior and morphology of prey species. In a system of tidepools at Nahant, Littorina littorea (the common Periwinkle) responded to increased C. maenas density by moving to other pools (Trussell et al. 2004). Softshell Clams (Mya arenaria) in the Damariscotta and Wells estuaries, Maine, burrowed deeper in the bottom sediment in the presence of C. maenas, responding both to chemical and mechanical signals (Whitlow et al. 2003; Flynn and Smee 2010). Whitlow (2010) found that chemical cues induced both deeper burrowing and growth of longer siphons in the clams. In Bodega Harbor, Calfiornia, predation by C. maenas resulted in reduced use of the lower intertidal zone by the native crab Hemigrapsus oregonensis, an effect that persisted, even after the abundance of C. maenas declined (de Rivera et al. 2011).

The invasion of Green Crabs has resulted in evolutionary changes in some prey populations, and in a possible ‘arms race’ as C. maenas has responded to these changes in its prey. For several species of gastropods in the Gulf of Maine, selective predation by C. maenas has apparently resulted in changes in shell morphology which make the shells more resistant to crushing. This has been shown for Littorina obtusata (Seeley 1986; Edgell et al. 2009; Edgell and Hollander 2011) and Nucella lapillus (Vermij 1982a). The picture for N. lapillus has been complicated by an overall increase in shell size over the last 80 years, which accounts for the increase in thickness when corrected for allometry, which could be a response to predation, or due to other causes (Fisher et al. 2009). This increase in shell strength, greatest in more southern populations, which have coexisted with C. maenas for a longer time, has been partially compensated for by an increase in crusher claw size and strength in more southern populations of C. maenas (Smith 2004; Edgell and Rochette 2008). The morphological response of Carcinus' crusher claw may be limited in northern populations by metabolic effects of temperature (Baldridge and Smith 2008).

These temporal and geographical differences have not been found in Littorina littorea, possibly because of the long-range dispersal of its planktonic larvae (Vermeij 1982b) or because of its ancestral co-occurrence with C. maenas (Edgell and Rochette 2008). Edgell and Rochette (2008) found that Carcinus claw scars and shell damage were less frequent on L. littorea than on L. obtusata.

Competition- Carcinus maenas is a potential competitor with native crabs, but this has not been well-studied on the Atlantic coast. In experiments on antagonistic behavior, the largest crab usually wins, which favors Callinectes sapidus (Blue Crab) because of its larger adult size (Ruiz et al. unpublished data; de Rivera et al. 2005). In competition for food, C. maenas may have a disadvantage against the faster-moving swimming crabs (Callinectes sapidus, Ovalipes ocellatus- Calico Crab) (Ropes 1989; Ruiz et al. unpublished data). Competition may restrict the penetration of C. maenas into estuarine habitats favored by C. sapidus. Interference competition and aggression occur between Carcinus maenas and Hemigrapsus sanguineus. In experiments, interference between the two species lowered the predation rates of both species on amphipods (Griffen and Byers 2006). In Tasmania, the invasion of Carcinus maenas apparently resulted in the displacement of the native crab Pachygrapsus gaimardi (Ruiz et al. unpublished). Caging experiments in King Georges Sound, Tasmania, showed apparent competition between C. maenas and the introduced starfish Asterias amurensis. The two species overlapped in depth range, and prey choice, but showed partitioning, with C. maenas preferring shallower water and smaller clams.

Food/Prey- Breen and Metaxas (2009) found little evidence of competition when juvenile C. maenas, and native Rock Crabs (Cancer irroratus) of similar size were reared together. Instead, the growth rate of C. irroratus increased, as a result of feeding on green crabs (Breen and Metaxas 2009).

Trophic Cascades- As a novel top predator in many littoral ecosystems, C. maenas invasions have resulted in effects across several trophic levels, affecting organisms which do not interact directly with the crabs. In a system of tidepools at Nahant, Massachusetts Bay, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools. The reduction of grazing resulted in increased growth of ephemeral red and green algae (Trussell et al. 2004). Similarly, in the Gulf of Maine, Carcinus maenas preyed intensely on the sea slug Placida dendritica, which grazes on the introduced alga Codium fragile, which could favor the growth of the seaweed in Green Crab habitats, such as enclosed harbors and estuaries (Harris and Jones 2005). After the Carcinus maenas invasion in Bodega Bay Harbor, California, several invertebrate species, including the polychaetes Exogene sp. and Lumbrinereis sp. and the tanaid Leptochelia dubia increased in abundance, probably as an indirect effect of reduction in Nutricola spp. populations (Grosholz et al. 2000). The introduced clam Gemma gemma increased dramatically (two orders of magnitude) after the Carcinus invasion, apparently because of decreased competition from native Nutricola clams (Grosholz 2005). In nearby Tomales Bay, the invasion of C. maenas combined with that of the introduced Atlantic Oyster Drill (Urosalpinx cinerea) nearly eliminated the native Olympic Oyster (Ostrea lurida) from the inner, low-salinity, region of Tomales Bay (Kimbro et al. 2009).


Regional Impacts

NA-ET3Cape Cod to Cape HatterasEcological ImpactPredation
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). 
NA-ET3Cape Cod to Cape HatterasEconomic ImpactFisheries
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.
NA-ET2Bay of Fundy to Cape CodEcological ImpactPredation
Carcinus maenas preys on native invertebrate communities in the Gulf of Maine. Its prey in this region include the barnacle Semibalanus balanoides, the native periwinkle Littorina obtusataNucella lapillus (Dogwhelk) (Rangely and Thomas 1987), egg capsules of Nassarius obsoletus, and probably those of other snails, as well as Mya arenaria (Soft-Shelled Clam) (Dow and Wallace 1952; Glude 1955; Brenchley 1982; Rangely and Thomas 1987). In the tidal Damariscotta River estuary, and the exposed Pemaquid Point, predation by C. maenas limited recruitment of Blue Mussels (Mytilus edulis), in areas with slow current flow (Bertness et al. 2002; Bertness et al. 2004). Since the arrival of C. maenas, populations of the poorly dispersing N. lapillus and L. obtusata have developed thicker shells, increasing resistance to predation (Vermeij 1982a; Seeley 1986). [However, overall shell length of N. lapillus also increased sufficiently to account for increased shell thickness, suggesting that factors other than predation- including, temperature, wave action, etc, may have influenced this trend (Fisher et al. 2009).] Evidence for the impacts of C. maenas include observed declines in clam populations after its arrival (Glude 1955), gut contents examination, and laboratory experiments (Rangeley and Thomas 1987).

Shells of Littorina obtusata (Smooth Periwinkle) from the northern and southern Gulf of Maine show differences in shell thickness related to Carcinus maenas abundance and the length of exposure to the invader (~100+ years for southern Gulf, ~50 years for northern Gulf). These differences are indicative of natural selection by Carcinus predation. These temporal and geographical differences have not been found in Littorina littorea, possibly because of the long-range dispersal of its planktonic larvae (Vermeij 1982b). In L. obtusata, shell thickness is increased after the snail is exposed to odors of C. maenas and is larger when accompanied by the odor of crushed L. obtusata (Trussell and Nicklin 2002). This response is greater in southern Gulf populations than those from Quoddy Bay (Trussell and Nicklin 2002). A similar difference in antiipredator responses to C. maenas between northern and southern Maine populations was seen in the Dogwinkle Nucella lapillus (Large and Smee 2013). In a system of tidepools at Nahant, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools (Trussell et al. 2004).

Interactions among crabs of different sizes often result in predation, either among crabs of the same species or different species. Large C. maenas prey on small Hemigrapsus sanguineus and vice versa (Griffen and Byers 2009). Predation, aggression, and interference behavior have the effect of reducing the predation rates of both species when the co-occur.  Experiments and modeling indicate that predation by Carcinus maenas and Hemigrapsus sanguineus is likely to reduce the use of intertidal habitats by the native Cancer irroratus (Rock Crab) in the Gulf of Maine (Griffen and Riley 2015). In laboratory experiments, Carcinus maenas was found to consume juvenile lobsters in 6 of 11 trials (Rossong et al. 2006). However, field and laboratory experiments (in Passamquoddy Bay, New Brunswick and the Isles of Shoals, Maine) indicate that rates of predation are low, and that predation on Green Crabs by lobsters may be equally or more frequent (League-Pike and Shulman 2009; Lynch and Rochette 2009).

Predation by Carcinus maenas has affected the behavior and morphology of Softshell Clams (Mya arenaria) in the Gulf of Maine. In the Wells estuary, clams burrow deeper in the presence of crabs. This is triggered by chemical clues, which also induce growth of longer siphons (Whitlow et al. 2003; Whitlow 2010). High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. This population growth was associated with an absence of young Softshell Clams (Mya arenaria) (Neckles 2015).
NA-ET2Bay of Fundy to Cape CodEconomic ImpactFisheries
Carcinus maenas preys on commercial shellfish in the Gulf of Maine. Its primary prey there has been Mya arenaria (Soft-Shell Clam). Decreased landings and rapid mortality of newly planted clams has been observed as C. maenas invaded new localities in the Gulf of Maine (Dow and Wallace 1952; Glude 1955; Smith et al. 1955). Tan and Beal (2015) tested various types of netting used to exclude Green Crabs, and found that significant predation occurred, even when small clams were protected by netting, Crab predation can be underestimated, because some clams are consumed without damage to the shells (Tan and Beal 2015). Carcinus maenas does have minor commercial value as a bait animal.
NEP-VNorthern California to Mid Channel IslandsEcological ImpactPredation
In Bodega Harbor CA, abundances of the clams Nutricola tantilla and N. confusa and the native crab Hemigrapsus oregonensis were sharply reduced after the invasion of Carcinus maenas. Experiments indicated high rates of feeding on the native clams and crabs (Grosholz et al. 2000). Over an 11-year period in Bodega Harbor, H. oregonensis abundance was negatively correlated with C. maenas abundance, but recovered, with a lag period, when C. maenas declined. However, C. maenas predation had persisting effects on the size and intertidal distribution of H. oregonensis (de Rivera et al. 2011). In Tomales Bay, Carcinus maenas is a less effective predator than the native crab (Cancer antennarius), on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009).
NEP-VNorthern California to Mid Channel IslandsEcological ImpactCompetition
In laboratory experiments, Carcinus maenas spent more time around bivalve bait than the native crab Hemigrapsus oregonensis, and was more successful at approaching competitors surrounding the bait than H. oregonensis, in Bodega Bay Harbor CA (Jensen et al. 2002). Carcinus maenas also displaces Metacarcinus magister (Dungeness Crabs) of equal size in feeding trials, and causes M. magister to emigrate from shelters in laboratory trials (McDonald et al. 2001). In enclosure experiments, Green Crabs reduced the abundance and quality of food available for wintering shorebirds (Dunlin, Calidris alpina) (Estelle and Grosholz 2012).
NEP-VNorthern California to Mid Channel IslandsEcological ImpactTrophic Cascade
After the Carcinus maenas invasion in Bodega Bay Harbor, California, several invertebrate species, the polychaetes Exogene sp. and Lumbrinereis sp. and the tanaid Leptochelia dubia increased in abundance, probably as an indirect effect of reduction in Nutricola spp. populations (Grosholz et al. 2000). The introduced clam Gemma gemma increased dramatically (two orders of magnitude) after the Carcinus invasion, apparently because of decreased competition from native Nutricola clams (Grosholz 2005). In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius, on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009). The increased abundance of U. cinerea, also more tolerant of low salinity than native whelks, has resulted in increased mortality and a near-absence of the native Olympia Oyster (Ostrea lurida).
WA-IVNoneEcological ImpactCompetition
Competition with native crabs is expected to be limited because of differences in habitat use (Griffiths et al. 1992).
AUS-IXNoneEcological ImpactPredation
Abundance of Carcinus maenas was negatively correlated with that of the native venerid clam Katelysia scalarina. In caging experiments, predation rates of C. maenas greatly exceeded those of native crabs or other predators. Predation was concentrated on the smallest size-class of K. scalaris (Walton et al. 2002). Subtidal caging experiments in King Georges Sound, Tasmania, also showed that C. maenas had a major predatory impact on the bivalves Fulvia tenuicostata and Katelysia rhytiphora (Ross et al. 2004).
AUS-IXNoneEcological ImpactCompetition
The invasion of Carcinus maenas apparently resulted in the displacement of the native crab Pachygrapsus gaimardi (Ruiz et al. unpublished). Caging experiments in King Georges Sound, Tasmania, showed apparent competition between C. maenas and the introduced starfish Asterias amurensis. The two species overlapped in depth range, and prey choice, but showed partitioning, with C. maenas preferring shallower water and smaller clams (Ross et al. 2004).
AUS-IXNoneEconomic ImpactFisheries
Predation by Carcinus maenas is expected to adversely affect the fishery for the clam Katelysia scalarina in Tasmania (Walton et al. 2002).
N195_CDA_N195 (Cape Cod)Economic ImpactFisheries
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).
N195_CDA_N195 (Cape Cod)Ecological ImpactPredation
Carcinus maenas is a major predator on commercial shellfish 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). This species is well-known as a shellfish pest in this area.
NA-ET1Gulf of St. Lawrence to Bay of FundyEcological ImpactPredation
Breen and Metaxas (2008) measured predation rates of juvenile and adult C. maenas on mussels (Mytilus sp.) and compared them to two species of native crabs (Cancer irroratus and Dyspanopeus sayi). Rates of mussel consumption were similar to or lower than native species. However, warm years can result in high recruitment, causing juvenile C. maenas to greatly outnumber native crabs, resulting in increased predation impacts (Breen and Metaxas 2008). Matheson and Gagnon (2012) compared feeding rates of C. maenas and C. irroratus and found that C. maenas had a preference for smaller mussels, compared to C. irroratus. In Kejimkujik National Park Seaside, Nova Scotia, modeling of a removal of Green Crabs from a sandflat resulted in a prediction of increased abundance of a variety of benthic invertebrates. However, these changes were predicted to be small, compared to the impact of migrating shorebirds (Wong and Dowd 2014). In citizen science field samples at 29 sites in the southern Gulf of St. Lawrence, there was a negative correlation between C. maenas and Say's Mud Crab (Dyspanopeus sayi). Large (70-80 mm diameter) Green Crabs fed on Mud Crabs at about twice the rate as on similarly sized juvenile Green Crabs (25-30 mm) in unstructured sand habitats, but preyed on both types of small crabs at about the same rate in oyster beds. Habitat complexity appears to affect the impact of Green Crab predation (Gehrels et al. 2016). In sandy and muddy sediments on Prince Edward Island, Carcinus maenas digs numerous pits in sandy and muddy sediments. Pits in muddy sediiment have reduced numbers of polychaetes and small bivalves (Lutz-Collins et al. 2016).
P110Tomales BayEcological ImpactPredation
In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius (California Rock Crab), on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009).
P110Tomales BayEcological ImpactTrophic Cascade
In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius, on native (Acanthinucella spirata, Angular Unicorn Whelk) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009). The increased abundance of U. cinerea, also more tolerant of low salinity than native whelks has resulted in increased mortality and a near-absence of the native Olympia Oyster (Ostrea lurida).
N180Cape Cod BayEcological ImpactPredation
Carcinus maenas was the most voracious predator of egg capsules of Ilyanassa obsoleta (Brenchley 1982).
NA-S3NoneEconomic ImpactFisheries
In cage experiments on a mudflat in Pomquet Harbour, Nova Scotia, Carcinus maenas removed 80% of small Softshell Clams (Mya arenaria), but had negligable impacts on larger clams (Floyd and Williams 2004). In experimental trials on Prince Edward Island, Green Crabs preyed on juvenile quahogs (Mercenaria mercenaria), blue mussels (Mytilus edulis), soft-shell clams (Mya arenaria), and oysters (Crassostrea virginica), and preferred mussels and clams in choice experiments (Miron et al. 2005). In predation experiments, large and medium C. maenas caused high mortality among small (35-55 mm long) Eastern Oysters, posing a problem for oyster aquaculature (Pickering et al. 2017; Poirier et al. 2017). The possibility of a managed fishery, on Prince Edward Island, has been studied, but its success would be determined by market prices (St. Hilaire et al. 2016). Large numbers of Green Crabs and naitve Rock Crabs (Cancer irroratus) decrease the number of American lobsters entering lobster traps, but it is not related to invasion status (
NA-S3NoneEcological ImpactPredation
In cage experiments on a mudflat in Pomquet Harbour, Nova Scotia, Carcinus maenas removed 80% of small Softshell Clams (Mya arenaria), but had negligable impacts on larger clams (Floyd and Williams 2004). In experimental trials on Prince Edward Island, Green Crabs preyed on juvenile quahogs (Mercenaria mercenaria), blue mussels (Mytilus edulis), soft-shell clams (Mya arenaria), and oysters (Crassostrea virginica), and preferred mussels and clams over oysters in choice experiments (Miron et al. 2005). Pickering and Quijon (2011) also found a similar pattern, with a strong preference for soft-shell clams (Mya arenaria) over mussels and oysters, particularly for small crabs (35-45 mm), which did not feed on large mussel and oysters at all, in choice experiments. Feeding rates of small, medium, and large C. maenas were highest on small bivalves, especially soft-shell clams (Pickering and Quijon 2011). In predation experiments, large and medium C. maenas caused high mortality among small (35-55 mm long) Eastern Oysters (Pickering et al. 2017; Poirier et al. 2017).
P112_CDA_P112 (Bodega Bay)Ecological ImpactPredation
In Bodega Harbor CA, abundances of the clams Nutricola tantilla and N. confusa and the native crab Hemigrapsus oregonensis were sharply reduced after the invasion of Carcinus maenas. Experiments indicated high rates of feeding on the native clams and crabs (Grosholz et al. 2000). Over an 11-year period in Bodega Harbor, H. oregonensis abundance was negatively correlated with C. maenas abundance, but recovered, with a lag period, when C. maenas declined. However, C. maenas predation had persisting effects on the size and intertidal distribution of H. oregonensis (de Rivera et al. 2011).
P112_CDA_P112 (Bodega Bay)Ecological ImpactCompetition
In laboratory experiments, Carcinus maenas spent more time at bivalve baits than the native crab Hemigrapsus oregonensis, and was more successful at approaching competitors surrounding bait than H. oregonensis, in Bodega Harbor California (Jensen et al. 2002). Carcinus maenas also displaces Metacarcinus magister (Dungeness Crabs) of equal size in feeding trials, and causes M. magister to emigrate from shelters in laboratory trials (McDonald et al. 2001). In enclosure experiments, Green Crabs reduced the abundance and quality of food available for wintering shorebirds (Dunlin, Calidris alpina) (Estelle and Grosholz 2012).
P112_CDA_P112 (Bodega Bay)Ecological ImpactTrophic Cascade
After the Carcinus maenas invasion in Bodega Bay Harbor, California, several invertebrate species, specifically the polychaetes Exogene sp. and Lumbrinereis sp. and the tanaid Leptochelia dubia increased in abundance, probably as an indirect effect of reduction in Nutricola spp. populations (Grosholz et al. 2000). The introduced clam Gemma gemma increased dramatically (two orders of magnitude) after the Carcinus invasion, apparently because of decreased competition from native Nutricola clams (Grosholz 2005).
NEP-VNorthern California to Mid Channel IslandsEconomic ImpactFisheries
In Bodega Bay, Caliornia, Manila Clams (Venerupis philippinarum) planted in mesh bags, were prone to heavy predation by Carcinus maenas. Predation was reduced by planting the clams later in the season, when the clams were larger (Grosholz et al. 2001). Estimated current losses of bivalve fisheries (Pacific Littleneck, Japanese Littleneck, Softshell Clam, Blue Mussel) in California are negligable, but with future population increases of C. maenas, could reach $20,000-60,000 per year (Grosholz et al. 2011).
P112_CDA_P112 (Bodega Bay)Economic ImpactFisheries
In Bodega Bay, California, Manila Clams (Venerupis philippinarum) planted in mesh bags, were prone to heavy predation by Carcinus maenas. Predation was reduced by planting the clams later in the season, when the clams were larger (Grosholz et al. 2000).
M040Long Island SoundEcological ImpactPredation
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 more 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 the Niantic River, Long Island Sound had a small predatory impact (1-8% of daily mortality) on newly settled juveniles of the Winter Flounder (Pseudopleuronectes americanus). This predation rate is probably less than that of other predators.
M040Long Island SoundEconomic ImpactFisheries
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 more important predators, because of their ability to climb eelgrass blades where young Argopecten were attached (Pohle et al. 1991).
N170Massachusetts BayEcological ImpactPredation
Shells of Littorina obtusata (Smooth Periwinkle) collected in Nahant, Massachusetts Bay, before 1900, and in 1982-84, show a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986). In L. obtusata, the shell thickness is increased after the snail is exposed to odors of C. maenas and is larger when accompanied by the odor of crushed L. obtusata, and this response is greater in southern Gulf populations (Trussell and Nicklin 2002). In a system of tidepools at Nahant, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools (Trussell et al. 2004).
N135_CDA_N135 (Piscataqua-Salmon Falls)Ecological ImpactPredation
Shells of Littorina obtusata (Smooth Periwinkle) collected in Appledore Island, Gulf of Maine, before 1900, and in 1982-84, showed a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986).
N045_CDA_N045 (Maine Coastal)Ecological ImpactPredation
Shells of Littorina obtusata (Smooth Periwinkle) collected at Isle au Haut, Gulf of Maine, before 1900, and in 1982-84, show a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986).
N010Passamaquoddy BayEcological ImpactPredation
Shells of Littorina obtusata (Smooth Periwinkle) at Gleason Point and Sipp Bay show differences in shell morphology (high-spired and low-spired), related to Carcinus maenas abudance, indicative of natural selection by Carcinus predation (Seeley 1986). In L. obtusata, the shell thickness is increased after the snail is exposed to odors of C. maenas and is larger when accompanied by the odor of crushed L. obtusata, and this response is greater in southern Gulf populations than those from Quoddy Bay (Trussell and Nicklin 2002).
M020Narragansett BayEcological ImpactPredation
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).
NA-ET2Bay of Fundy to Cape CodEcological ImpactTrophic Cascade
In a system of tidepools at Nahant, Massachusetts, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools. The reduction of grazing resulted in increased growth of ephemeral red and green algae (Trussell et al. 2004). Although it had a direct predatory effect on mussls and barnacles in community experiments, Carcinus maenas had an indirect positive effect by preying on the dogwhelk Nucella lapillus (Griffen and Byers 2009). In laboratory experiments, C. maenas preyed intensely on the sea slug Placida dendritica, which grazes on Codium fragile, which could favor the growth of the seaweed in favorable habitats for C. maenas, such as enclosed harbors and estuaries (Harris and Jones 2005). Caging experiments show that compettion by Carcinus maenas reduces abudances of the Marsh Crab (Sesarma reticulum) by evicting the smaller crabs from their burrows, and exposing the Marsh Crabs to predation. The reduction in Marsh Crab hebivory has resulted in increased growth and recovery of Spartina alterniflora saltmarshes. The previous decline of the Spartina marshes has been attrributed to an increase in the herbivorous Marsh Crab, triggered by heavy fishing fot predatory fishes (Coverdale et al. 2013).
NA-ET2Bay of Fundy to Cape CodEcological ImpactCompetition
Interference competition and aggression occur between Carcinus maenas and Hemigrapsus sanguineus. In experiments, interference between the two species lowered the predation rates of both species on amphipods (Griffen and Byers 2006). In laboratory experiments, Carcinus maenas was found to compete with juvenile lobsters for food and shelter (Rossong et al. 2006). However, in field studies in Passamaquoddy Bay, the two species did not seem to interact (Lynch and Rochette 2009). In Lynch and Rochette's experiments, agonistic behavior was rare. Carcinus maenas did compete with the native Dogwhelks (Nucella lapillus in Passamaquoddy Bay, interfering with whelks feeding on mussels (Mytilus edulis), and stealing prey from them. This kleptoparasitism may enable crabs to feed on mussels larger than they can open by themselves (Quinn et al. 2012).
N130Great BayEcological ImpactPredation
Interactions among crabs of different sizes often result in predation, either among crabs of the same species or different species. Large C. maenas prey on small Hemigrapsus sanguineus and vice versa (Griffen and Byers 2009). Predation, aggression, and interference behavior have the effect of reducing the predation rates of both species when they co-occur. Crabs for these experiments were collected at Odiorne Point, New Hampshire.
N130Great BayEcological ImpactCompetition
Interference competition and agression occur between Carcinus maenas and Hemigrapsus sanguineus. In experiments, interference between the two species lowered the predation rates of both species on amphipods (Griffen and Byers 2006). Crabs for these experiments were collected at Odiorne Point, New Hampshire.
NA-ET3Cape Cod to Cape HatterasEcological ImpactCompetition
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).
NA-ET1Gulf of St. Lawrence to Bay of FundyEcological ImpactCompetition
In laboratory experiments, juvenile C. maenas initially reduced the growth rate of small (below 19-22 mm carapace width) Cancer irroratus (Rock Crabs) (Breen and Metaxas 2009). In experiments, Green Crabs reduced foraging of Rock Crabs, especially at warmer temperatures (Matheson and Gagnon 2012). Modelling of the impacts of removal of Green Crabs in Kejimkujik National Park Seaside, Nova Scotia,predicted an an increase of small shorebirds (eg. Black-bellied Plover, Pluvialis squatarola), because the increase in small prey (polychaetes, bivalves, small crustaceans) offset the decreased availabilty of Green Crabs as prey. However, these impacts were predicted to be small (Wong and Dowd 2014).
NA-ET1Gulf of St. Lawrence to Bay of FundyEcological ImpactFood/Prey
Breen and Metaxas (2009) found that when C. maenas and Cancer irroratus of similar size (above 19-22 mm carapace width) were reared together, the growth rate of C. irroratus increased, as a result of feeding on green crabs (Breen and Metaxas 2009). In modeling of the foodweb inl ejimkujik National Park Seaside, Nova Scotia, potential removal of Green Crabs resulted in a decreased in gull (Larus spp.) biomass due to the decrease of a major prey item (Wong and Dowd 2014).
NA-ET2Bay of Fundy to Cape CodEcological ImpactFood/Prey
Field and laboratory experiments in Passamquoddy Bay, New Brunswick and the Isles of Shoals, Maine indicate that Green Crab are frequent prey for American Lobsters (Homarus americanus) and their vulnerability to predation limits C. maenas subtidal distribution (League-Pike and Shulman 2009; Lynch and Rochette 2009).
N135_CDA_N135 (Piscataqua-Salmon Falls)Ecological ImpactFood/Prey
Field and labooratory experiments on the Isles of Shoals, Maine indicate that Carcinus maenas are frequent prey for American Lobsters (Homarus americanus) and that their vulnerability to predation limits C. maenas subtidal distribution (League-Pike and Shulman 2009).
N070Damariscotta RiverEcological ImpactPredation
Softshelll Clams (Mya arenaria) in the Damariscotta estuary, Maine, burrowed deeper in the bottom sediment in the presence of C. maenas, responding both to chemical and mechanical signals (Flynn and Smee 2010). In the tidal Damariscotta River estuary, predation by C. maenas limited recruitment of Blue Mussels (Mytilus edulis), in areas with slow current flow (Bertness et al. 2002). On exposed Pemaquid Point, exclusion of C. maenas by cages from cleared areas of rocky shore led to much more rapid colonization by mussels than from control areas (Bertness et al. 2004).
NEP-IVPuget Sound to Northern CaliforniaEcological ImpactPredation
Carcinus maenas fed at lower rates overall than native Metacarcinus magister (Dungeness Crab), collected from the Oregon coast (no location specified), when feeding on native mussels (Mytilus trossulus), but were more efficient than equal-sized M. magister at feeding on native Olympia Oysters, Ostrea lurida, because of greater claw strength (Yamada et al. 2010). Palacios and Ferraro (2003) found that Carcinus maenas preferred O. lurida to 3 other species of bivalves (introduced Venerupis philippinarum (Japanese Littleneck) and native Macoma nasuta (Bent-nose Macoma) and Cryptomya californica (California Softshell), when offered in equal amounts.
N120Wells BayEcological ImpactPredation
Predation by Carcinus maenas has affected the behavior and morphology of Softshell Clams (Mya arenaria) in the Gulf of Maine. In the Wells estuary, clams burrow deeper in the presence of crabs. This is triggered by chemical cues, which also induce growth of longer siphons (Whitlow et al. 2003; Whitlow 2010).
N170Massachusetts BayEcological ImpactTrophic Cascade
In a system of tidepools at Nahant, Massachusetts, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools. The reduction of grazing resulted in increased growth of ephemeral red and green algae (Trussell et al. 2004). Carcinus maenas, although it had a direct predatory effect on mussels and barnacles, in community experiments, had an indirect positive effect by preying on the dogwhelk Nucella lapillus (Griffen and Byers 2009).
WA-IVNoneEcological ImpactPredation
Carcinus maenas could be an important predator in protected waters (Griffiths et al. 1992).
P210Yaquina BayEcological ImpactPredation
Palacios and Ferraro (2003) found that Carcinus maenas preferred O. lurida to 3 other species of bivalves (introduced Venerupis philippinarum (Japanese Littleneck) and native Macoma nasuta (Bent-nose Macoma) and Cryptomya californica (California Softshell), when offered in equal amounts.
N070Damariscotta RiverEcological ImpactTrophic Cascade
In the tidal Damariscotta River estuary, predation by C. maenas limited growth of mussels (Mytilus edulis), in areas with slow current flow, leading to the domination of the large seaweedAscophyllum nodosum (Bertness et al. 2002).
N080Sheepscot BayEcological ImpactPredation
Dogwinkles (Nucella lapillus from protected locations Bootbay Harbor showed a sharp reduction in movements, and an increase in shell thickness, when exposed to odors from C. maenas, a response not seen in snails feom exposed locations, or form northern Maine, with less exposure, or a shorter history of exposure to Green Crab predation (Large and Smee 2013).
N020Englishman/Machias BayEcological ImpactPredation
Predation on commercially important Mya arenaria (Soft Shell Clam) was studied experimentally in Holmes Bay, Cutler ME. Recruitment was greatly reduced in open versus protected areas (Tan and Beal 2015).
N020Englishman/Machias BayEconomic ImpactFisheries
Tan and Beal (2015) tested various types of netting used to exclude Green Crabs, and found that significant predation occurred, even when small clams were protected by netting, Crab predation can be underestimated, because some clams are consumed without damage to the shells (Tan and Beal 2015).
NA-S3NoneEcological ImpactHabitat Change
Severe declines in an Eelgrass (Zostera marina) bed in Antigonish Harbour, Gulf of St. Lawrence, Nova Scotia, were associated with foraging by abundant Green Crabs (Carcinus maenas uprooting and and damaging the plants. Enclosure experiments supported the role of the crabs in the damage to Eelgrass beds (Garbary et al. 2014).
NA-ET1Gulf of St. Lawrence to Bay of FundyEcological ImpactHabitat Change
In sandy and muddy sediments on Prince Edward Island, Carcinus digs numerous pits. The pits in sandy sediment fill rapidly, and do not differ from undisturbed areas, while pits in muddy sediments fill more slowly, and differ in their infauna, mostly in having smaller numbers of small polychaetes (Lutz-Collins et al. 2016). In Placentia and Bonaventure Bays, Newfoundland, disturbance due to foraging Green Crabs, has resulted in a reduction of Eelgrass (Zostera marina) cover, up to 50% removal, based on Before-After-Control Impact studies (Matheson et al. 2016).
N100Casco BayEcological ImpactHabitat Change
High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. The population explosion was associated with a sharp reduction of Eelgrass (Zostera marina) in upper Casco Bay, due to damage to the plants during foraging. Exclosure experiments found that survival of eelgrass shoots was 82% inside the exclosures, but 24% outside (Neckles 2015).
N100Casco BayEcological ImpactPredation
High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. This population growth was associated with an absence of young Softshell Clams (Mya arenaria) (Neckles 2015).
NA-ET2Bay of Fundy to Cape CodEcological ImpactHabitat Change
High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. The population explosion was associated with a sharp reduction of Eelgrass (Zostera marina) in upper Casco Bay, due to damage to the plants during foraging. Exclosure experiments found that survival of eelgrass shoots was 82% inside the exclosures, but 24% outside (Neckles 2015).
NA-ET1Gulf of St. Lawrence to Bay of FundyEcological ImpactTrophic Cascade
In Placentia and Bonaventure Bays, Newfoundland, disturbance due to foraging Green Crabs, has resulted in a reduction of Eelgrass (Zostera marina), up to 50% removal. The loss of eelgrass has led to a sharp reduction in fish biomass and abundance, probably due both to the loss of shelter and the associated invertebrate community (Matheson et al. 2016).
N180Cape Cod BayEcological ImpactCompetition
Caging experiments show that predation by Carcinus maenas reduce abudances of the Marsh Crab (Sesarma reticulum) by evicting the smaller crabs from their burrows. The Green Crabs use these burrows as a refuge from predation (Coverdale et al. 2013).
N180Cape Cod BayEcological ImpactTrophic Cascade
Caging experiments show that compettion by Carcinus maenas reduces abudances of the Marsh Crab (Sesarma reticulum) by evicting the smaller crabs from their burrows, and exposing the Marsh Crabs to predation. The reduction in Marsh Crab hebivory has resulted in increased growth and recovery of Spartina alterniflora saltmarshes. The previous decline of the Spartina marshes has been attrributed to an increase in the herbivorous Marsh Crab, triggered by heavy fishing fot predatory fishes (Coverdale et al. 2013).
NEP-IIIAlaskan panhandle to N. of Puget SoundEcological ImpactHabitat Change
In enclosure experiments, in Barkely Sound, Briitsh Columbia, high densities of Green Crabs resulted in rapid declines of Eelgrass (Zostera marina density (Howard et al. 2019).
NEP-IIIAlaskan panhandle to N. of Puget SoundEcological ImpactHerbivory
In experiments, in Barkely Sound, Briitsh Columbia, Green Crabs shredded Eelgrass blades, but also directly consumed rhizomes (Howard et al. 2019).
NA-S3NoneEcological ImpactFood/Prey
American Lobsters (Homarus americanus) in lobster traps prey on both Green Crabs and Rock Crabs (Cancer irroratus) (Zargarpour et al. 2020).
SA-INoneEcological ImpactFood/Prey

Carcinus maenas is a food item (though not a major one) for the native Kelp Gull (Larus dominicus,(Yorio et al. 2020).

NEP-IIIAlaskan panhandle to N. of Puget SoundEcological ImpactCompetition
In experiments, Green Crabs showed a type II feeding response, while native Red Rock Crabs (Cancer productus) have a type III response, meaning that Green Crabs feed at a higher rate on Pacific Oysters (Magallana gigas) at low prey densites (Ens et a.1. 2021).
OROregonEcological ImpactPredation
Palacios and Ferraro (2003) found that Carcinus maenas preferred O. lurida to 3 other species of bivalves (introduced Venerupis philippinarum (Japanese Littleneck) and native Macoma nasuta (Bent-nose Macoma) and Cryptomya californica (California Softshell), when offered in equal amounts.
CACaliforniaEcological ImpactCompetition

In laboratory experiments, Carcinus maenas spent more time around bivalve bait than the native crab Hemigrapsus oregonensis, and was more successful at approaching competitors surrounding the bait than H. oregonensis, in Bodega Bay Harbor CA (Jensen et al. 2002). Carcinus maenas also displaces Metacarcinus magister (Dungeness Crabs) of equal size in feeding trials, and causes M. magister to emigrate from shelters in laboratory trials (McDonald et al. 2001). In enclosure experiments, Green Crabs reduced the abundance and quality of food available for wintering shorebirds (Dunlin, Calidris alpina) (Estelle and Grosholz 2012).  In laboratory experiments, Carcinus maenas spent more time at bivalve baits than the native crab Hemigrapsus oregonensis, and was more successful at approaching competitors surrounding bait than H. oregonensis, in Bodega Harbor California (Jensen et al. 2002). Carcinus maenas also displaces Metacarcinus magister (Dungeness Crabs) of equal size in feeding trials, and causes M. magister to emigrate from shelters in laboratory trials (McDonald et al. 2001). In enclosure experiments, Green Crabs reduced the abundance and quality of food available for wintering shorebirds (Dunlin, Calidris alpina) (Estelle and Grosholz 2012).

CACaliforniaEcological ImpactPredation
In Bodega Harbor CA, abundances of the clams Nutricola tantilla and N. confusa and the native crab Hemigrapsus oregonensis were sharply reduced after the invasion of Carcinus maenas. Experiments indicated high rates of feeding on the native clams and crabs (Grosholz et al. 2000). Over an 11-year period in Bodega Harbor, H. oregonensis abundance was negatively correlated with C. maenas abundance, but recovered, with a lag period, when C. maenas declined. However, C. maenas predation had persisting effects on the size and intertidal distribution of H. oregonensis (de Rivera et al. 2011). In Tomales Bay, Carcinus maenas is a less effective predator than the native crab (Cancer antennarius), on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009)., In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius (California Rock Crab), on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009)., In Bodega Harbor CA, abundances of the clams Nutricola tantilla and N. confusa and the native crab Hemigrapsus oregonensis were sharply reduced after the invasion of Carcinus maenas. Experiments indicated high rates of feeding on the native clams and crabs (Grosholz et al. 2000). Over an 11-year period in Bodega Harbor, H. oregonensis abundance was negatively correlated with C. maenas abundance, but recovered, with a lag period, when C. maenas declined. However, C. maenas predation had persisting effects on the size and intertidal distribution of H. oregonensis (de Rivera et al. 2011).
CACaliforniaEcological ImpactTrophic Cascade
After the Carcinus maenas invasion in Bodega Bay Harbor, California, several invertebrate species, the polychaetes Exogene sp. and Lumbrinereis sp. and the tanaid Leptochelia dubia increased in abundance, probably as an indirect effect of reduction in Nutricola spp. populations (Grosholz et al. 2000). The introduced clam Gemma gemma increased dramatically (two orders of magnitude) after the Carcinus invasion, apparently because of decreased competition from native Nutricola clams (Grosholz 2005). In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius, on native (Acanthinucella spirata) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009). The increased abundance of U. cinerea, also more tolerant of low salinity than native whelks, has resulted in increased mortality and a near-absence of the native Olympia Oyster (Ostrea lurida)., In Tomales Bay, Carcinus maenas is a less effective predator than the native crab, Cancer antennarius, on native (Acanthinucella spirata, Angular Unicorn Whelk) and introduced whelks (Urosalpinx cinerea, Atlantic Oyster Drill), resulting in an increased abundance and habitat range of whelks in the inner Bay, where C. maenas better tolerates low salinities (Kimbro et al. 2009). The increased abundance of U. cinerea, also more tolerant of low salinity than native whelks has resulted in increased mortality and a near-absence of the native Olympia Oyster (Ostrea lurida)., After the Carcinus maenas invasion in Bodega Bay Harbor, California, several invertebrate species, specifically the polychaetes Exogene sp. and Lumbrinereis sp. and the tanaid Leptochelia dubia increased in abundance, probably as an indirect effect of reduction in Nutricola spp. populations (Grosholz et al. 2000). The introduced clam Gemma gemma increased dramatically (two orders of magnitude) after the Carcinus invasion, apparently because of decreased competition from native Nutricola clams (Grosholz 2005).
CACaliforniaEconomic ImpactFisheries
In Bodega Bay, Caliornia, Manila Clams (Venerupis philippinarum) planted in mesh bags, were prone to heavy predation by Carcinus maenas. Predation was reduced by planting the clams later in the season, when the clams were larger (Grosholz et al. 2001). Estimated current losses of bivalve fisheries (Pacific Littleneck, Japanese Littleneck, Softshell Clam, Blue Mussel) in California are negligable, but with future population increases of C. maenas, could reach $20,000-60,000 per year (Grosholz et al. 2011)., In Bodega Bay, California, Manila Clams (Venerupis philippinarum) planted in mesh bags, were prone to heavy predation by Carcinus maenas. Predation was reduced by planting the clams later in the season, when the clams were larger (Grosholz et al. 2000).
MAMassachusettsEcological ImpactCompetition
Caging experiments show that predation by Carcinus maenas reduce abudances of the Marsh Crab (Sesarma reticulum) by evicting the smaller crabs from their burrows. The Green Crabs use these burrows as a refuge from predation (Coverdale et al. 2013).
MAMassachusettsEcological ImpactPredation
Carcinus maenas is a major predator on commercial shellfish 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). This species is well-known as a shellfish pest in this area., Carcinus maenas was the most voracious predator of egg capsules of Ilyanassa obsoleta (Brenchley 1982)., Shells of Littorina obtusata (Smooth Periwinkle) collected in Nahant, Massachusetts Bay, before 1900, and in 1982-84, show a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986). In L. obtusata, the shell thickness is increased after the snail is exposed to odors of C. maenas and is larger when accompanied by the odor of crushed L. obtusata, and this response is greater in southern Gulf populations (Trussell and Nicklin 2002). In a system of tidepools at Nahant, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools (Trussell et al. 2004).
MAMassachusettsEcological ImpactTrophic Cascade
Caging experiments show that compettion by Carcinus maenas reduces abudances of the Marsh Crab (Sesarma reticulum) by evicting the smaller crabs from their burrows, and exposing the Marsh Crabs to predation. The reduction in Marsh Crab hebivory has resulted in increased growth and recovery of Spartina alterniflora saltmarshes. The previous decline of the Spartina marshes has been attrributed to an increase in the herbivorous Marsh Crab, triggered by heavy fishing fot predatory fishes (Coverdale et al. 2013)., In a system of tidepools at Nahant, Massachusetts, Littorina littorea (Common Periwinkle) responded to increased C. maenas density by moving to other pools. The reduction of grazing resulted in increased growth of ephemeral red and green algae (Trussell et al. 2004). Carcinus maenas, although it had a direct predatory effect on mussels and barnacles, in community experiments, had an indirect positive effect by preying on the dogwhelk Nucella lapillus (Griffen and Byers 2009).
MAMassachusettsEconomic ImpactFisheries
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).
MEMaineEcological ImpactHabitat Change
High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. The population explosion was associated with a sharp reduction of Eelgrass (Zostera marina) in upper Casco Bay, due to damage to the plants during foraging. Exclosure experiments found that survival of eelgrass shoots was 82% inside the exclosures, but 24% outside (Neckles 2015).
MEMaineEcological ImpactPredation
High densities of Green Crabs were reported by shellfishers in Casco Bay, coinciding with higher water temperatures in 2013. This population growth was associated with an absence of young Softshell Clams (Mya arenaria) (Neckles 2015)., Shells of Littorina obtusata (Smooth Periwinkle) at Gleason Point and Sipp Bay show differences in shell morphology (high-spired and low-spired), related to Carcinus maenas abudance, indicative of natural selection by Carcinus predation (Seeley 1986). In L. obtusata, the shell thickness is increased after the snail is exposed to odors of C. maenas and is larger when accompanied by the odor of crushed L. obtusata, and this response is greater in southern Gulf populations than those from Quoddy Bay (Trussell and Nicklin 2002)., Softshelll Clams (Mya arenaria) in the Damariscotta estuary, Maine, burrowed deeper in the bottom sediment in the presence of C. maenas, responding both to chemical and mechanical signals (Flynn and Smee 2010). In the tidal Damariscotta River estuary, predation by C. maenas limited recruitment of Blue Mussels (Mytilus edulis), in areas with slow current flow (Bertness et al. 2002). On exposed Pemaquid Point, exclusion of C. maenas by cages from cleared areas of rocky shore led to much more rapid colonization by mussels than from control areas (Bertness et al. 2004)., Shells of Littorina obtusata (Smooth Periwinkle) collected at Isle au Haut, Gulf of Maine, before 1900, and in 1982-84, show a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986)., Predation by Carcinus maenas has affected the behavior and morphology of Softshell Clams (Mya arenaria) in the Gulf of Maine. In the Wells estuary, clams burrow deeper in the presence of crabs. This is triggered by chemical cues, which also induce growth of longer siphons (Whitlow et al. 2003; Whitlow 2010)., Dogwinkles (Nucella lapillus from protected locations Bootbay Harbor showed a sharp reduction in movements, and an increase in shell thickness, when exposed to odors from C. maenas, a response not seen in snails feom exposed locations, or form northern Maine, with less exposure, or a shorter history of exposure to Green Crab predation (Large and Smee 2013)., Predation on commercially important Mya arenaria (Soft Shell Clam) was studied experimentally in Holmes Bay, Cutler ME. Recruitment was greatly reduced in open versus protected areas (Tan and Beal 2015).
MEMaineEcological ImpactTrophic Cascade
In the tidal Damariscotta River estuary, predation by C. maenas limited growth of mussels (Mytilus edulis), in areas with slow current flow, leading to the domination of the large seaweedAscophyllum nodosum (Bertness et al. 2002).
MEMaineEconomic ImpactFisheries
Tan and Beal (2015) tested various types of netting used to exclude Green Crabs, and found that significant predation occurred, even when small clams were protected by netting, Crab predation can be underestimated, because some clams are consumed without damage to the shells (Tan and Beal 2015).
NHNew HampshireEcological ImpactFood/Prey
Field and labooratory experiments on the Isles of Shoals, Maine indicate that Carcinus maenas are frequent prey for American Lobsters (Homarus americanus) and that their vulnerability to predation limits C. maenas subtidal distribution (League-Pike and Shulman 2009).
NHNew HampshireEcological ImpactPredation
Shells of Littorina obtusata (Smooth Periwinkle) collected in Appledore Island, Gulf of Maine, before 1900, and in 1982-84, showed a change in morphology (high-spired to low-spired) indicative of natural selection by Carcinus predation (Seeley 1986).
NA-S3NoneEcological ImpactHerbivory

Green Crabs (Carcinus maenas) were implicated in a decline of a protected population of Chondrus crispus (Irish Moss).  Removal programs were undertaken in two Prince Edward Island harbors, Murray Bay and Basin Head.  Populations were reduced to 30-40& of the initial level, with short-term crab reductions, and Irish Moss recovery (Tummon Flynn et al. 2023).

NA-S3NoneEcological ImpactHerbivory

Green Crabs (Carcinus maenas) were implicated in a decline of a protected population of Chondrus crispus (Irish Moss).  Removal programs were undertaken in two Prince Edward Island harbors, Murray Bay and Basin Head.  Populations were reduced to 30-40& of the initial level, with short-term crab reductions, and Irish Moss recovery (Tummon Flynn et al. 2023).

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
NA-ET1 Gulf of St. Lawrence to Bay of Fundy 1960 Def Estab
NA-ET2 Bay of Fundy to Cape Cod 1872 Def Estab
NA-ET3 Cape Cod to Cape Hatteras 1817 Def Estab
NEP-IV Puget Sound to Northern California 1995 Def Estab
NEP-V Northern California to Mid Channel Islands 1990 Def Estab
WA-IV None 1983 Def Estab
AUS-VIII None 1900 Def Estab
AUS-X None 1891 Def Estab
AUS-IX None 1993 Def Estab
AUS-VII None 1976 Def Estab
NWP-3b None 1984 Def Estab
NA-S3 None 1994 Def Estab
NEA-III None 0 Native Estab
NEA-II None 0 Native Estab
WA-I None 0 Native Estab
NEA-V None 0 Native Estab
NEA-IV None 0 Native Estab
AR-V None 0 Native Estab
B-I None 0 Native Estab
B-II None 0 Native Estab
B-III None 0 Native Estab
B-IV None 0 Native Estab
AR-IV None 0 Native Estab
AUS-IV None 1965 Def Failed
NEA-VI None 1861 Def Failed
SP-XXI None 1873 Def Failed
SA-III None 1898 Def Failed
CIO-II None 1886 Def Failed
SA-II None 1857 Def Failed
EA-III None 1922 Def Failed
RS-1 None 1817 Def Failed
IP-1 None 1971 Def Failed
SA-I None 2003 Def Estab
P090 San Francisco Bay 1990 Def Estab
M020 Narragansett Bay 1842 Def Estab
M040 Long Island Sound 1817 Def Estab
P130 Humboldt Bay 1995 Def Estab
M010 Buzzards Bay 1853 Def Estab
M060 Hudson River/Raritan Bay 1817 Def Estab
M080 New Jersey Inland Bays 1817 Def Estab
M090 Delaware Bay 1900 Def Estab
P270 Willapa Bay 1998 Def Estab
P170 Coos Bay 1997 Def Estab
N195 _CDA_N195 (Cape Cod) 1841 Def Estab
M128 _CDA_M128 (Eastern Lower Delmarva) 1876 Def Unk
M120 Chincoteague Bay 1995 Def Estab
M023 _CDA_M023 (Narragansett) 1851 Def Estab
N190 Waquoit Bay 1903 Def Estab
N180 Cape Cod Bay 1872 Def Estab
N170 Massachusetts Bay 1893 Def Estab
N165 _CDA_N165 (Charles) 1884 Def Estab
M050 Great South Bay 1817 Def Estab
M030 Gardiners Bay 1817 Def Estab
M036 _CDA_M036 (Southern Long Island) 1817 Def Estab
M070 Barnegat Bay 1973 Def Estab
N100 Casco Bay 1902 Def Estab
N036 _CDA_N036 (Maine Coastal) 1937 Def Estab
N010 Passamaquoddy Bay 1951 Def Estab
P095 _CDA_P095 (Tomales-Drakes Bay) 1993 Def Estab
P080 Monterey Bay 1993 Def Estab
P110 Tomales Bay 1993 Def Estab
P112 _CDA_P112 (Bodega Bay) 1993 Def Estab
P280 Grays Harbor 1998 Def Estab
N160 Plum Island Sound 1902 Def Estab
N070 Damariscotta River 1907 Def Estab
N060 Muscongus Bay 1912 Def Estab
N055 _CDA_N055 (Maine Coastal) 1907 Def Estab
N045 _CDA_N045 (Maine Coastal) 1930 Def Estab
N030 Narraguagus Bay 1950 Def Estab
N130 Great Bay 1902 Def Estab
N140 Hampton Harbor 2003 Def Estab
NEP-III Alaskan panhandle to N. of Puget Sound 1998 Def Estab
N185 _CDA_N185 (Cape Cod) 1904 Def Estab
N110 Saco Bay 1909 Def Estab
MED-I None 0 Native Estab
B-VII None 1928 Crypto Unk
B-VI None 1969 Crypto Unk
B-V None 0 Native Estab
P200 Alsea River 1998 Def Estab
P226 _CDA_P226 (Wilson-Trusk-Nestuccu) 1998 Def Unk
P230 Netarts Bay 1998 Def Estab
P240 Tillamook Bay 1998 Def Estab
CIO-IV None 1933 Def Failed
SEP-H None 1866 Def Failed
P100 Drakes Estero 1993 Def Estab
M130 Chesapeake Bay 2007 Def Unk
M110 Maryland Inland Bays 1995 Def Estab
M100 Delaware Inland Bays 2003 Def Estab
P070 Morro Bay 1998 Def Unk
P210 Yaquina Bay 1998 Def Estab
N140 Hampton Harbor 0 Def Estab
N135 _CDA_N135 (Piscataqua-Salmon Falls) 1986 Def Estab
P160 Coquille River 1997 Def Unk
N120 Wells Bay 2007 Def Estab
N050 Penobscot Bay 2007 Def Estab
N116 _CDA_N116 (Piscataqua-Salmon Falls) 2009 Def Estab
N125 _CDA_N125 (Piscataqua-Salmon Falls) 2009 Def Estab
N040 Blue Hill Bay 2009 Def Estab
N080 Sheepscot Bay 1907 Def Estab
N020 Englishman/Machias Bay 1976 Def Estab
P292 _CDA_P292 (San Juan Islands) 2016 Def Unk
P293 _CDA_P293 (Strait of Georgia) 2016 Def Unk
PAN_PAC Panama Pacific Coast 1866 Def Failed
P292 _CDA_P292 (San Juan Islands) 2016 Def Unk
P293 _CDA_P293 (Strait of Georgia) 2016 Def Unk
P288 _CDA_P288 (Dungeness-Elwha) 2017 Def Estab
AUS-XII None 1995 Def Failed
EAS-VIII None 2018 Def Failed
P293 _CDA_P293 (Strait of Georgia) 2016 Def None
P294 _CDA_P294 (Nooksack) 2021 Def Estab
P290 Puget Sound 2022 Def Estab
P290 Puget Sound 2022 Def Unk

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude
2490 Gould 1841; Verrill and Smith 1873 1873 1841-01-01 Marthas Vineyard Def 41.4167 -70.6167
2491 Verrill and Smith 1873; Sumner et al. 1913; 1873 1873-01-01 Woods Hole Def 41.5167 -70.6833
2492 MIT Seagrant 2003 2000 2000-08-11 New Bedford Def 41.6361 -70.9347
2493 MIT Seagrant 2003 2000 2000-08-05 Massachusetts Maritime Academy, Bourne Def 41.6539 -70.6592
2494 De Kay 1844 1842 1841-01-01 Newport Def 41.4900 -71.3133
2495 Leidy 1855 1851 1851-01-01 Point Judith Def 41.3632 -71.4842
2496 Rafinesque 1817 1817 1817-01-01 Long Island Def 41.0833 -73.0000
2497 Rathbun 1930 1884 1884-09-27 Fire Island Def 40.6577 -73.1006
2498 Say 1817 (?) 1817 1817-01-01 Little Egg Harbor Def 39.5900 -74.2780
2499 Loveland and Voughliotis 1984 1973 1973-01-01 Barnegat Bay Def 39.7814 -74.1686
2500 Rathbun 1930 1900 1900-01-01 Cape May Def 38.9350 -74.9064
2501 Leathem and Maurer 1980 1976 1976-01-01 Delaware Bay Def 38.7744 -75.1397
2502 Ruiz et al., unpublished data 1996 1996-01-01 Ocean City Def 38.3364 -75.0853
2503 Kingsley 1879 1875 1874-01-01 Hog Island Bay Def 37.4411 -75.7561
2504 MIT Seagrant 2003 2000 2000-08-10 Sandwich Def 41.7589 -70.4944
2505 MIT Sea Grant 2003 2000 2000-08-09 Plymouth Def 41.9583 -70.6678
2506 MIT Seagrant 2003 1893 1893-01-01 Cohasset Def 42.2417 -70.8042
2507 MIT Seagrant 2003 1902 1902-01-01 Nahant Def 42.4264 -70.9194
2508 MIT Seagrant 2003 2000 2000-08-07 Consititution Marina, Boston Def 42.3583 -71.0603
2509 MIT Seagrant 2003 2003 2003-08-03 Salem Def 42.5194 -70.8972
2510 MIT Seagrant 2003 2000 2000-08-08 Gloucester State Pier Def 42.6158 -70.6625
2511 Bryant 1906 1902 1902-01-01 Kittery Def 43.0881 -70.7367
2512 Bryant 1906; Rathbun 1930 1905 1905-01-01 Harpswell Def 43.6333 -70.0500
2513 Glude 1955 1939 1939-01-01 Winter Harbor Def 44.5922 -68.2040
2514 Glude 1955 1951 1951-01-01 Lubec Def 44.8606 -66.9847
2515 Glude 1955 1951 1951-01-01 St. Andrews Def 45.0667 -67.0333
2516 Glude 1955; Audet et al. 2003 1953 1953-01-01 Minas Basin Def 45.2500 -64.1667
2517 Audet et al. 2003 1966 1966-01-01 Halifax Def 44.6500 -63.6000
2518 Audet et al. 2003 1991 1991-01-01 Cape Breton Def 45.5833 -61.3833
2520 Cohen et al. 1995; Grosholz and Ruiz 1995 1989 1989-01-01 Drakes Estero Def 38.3478 -122.9531
2521 Cohen et al. 1995; Grosholz and Ruiz 1995 1990 1990-01-01 Redwood City Def 37.4853 -122.2353
2522 Cohen et al. 1995; Grosholz and Ruiz 1995 1992 1992-10-01 Redwood Creek (South Bay) Def 37.5250 -122.2000
2523 Cohen et al. 1995; Grosholz and Ruiz 1995 1994 1994-01-01 Benicia Def 38.0494 -122.1575
2524 Cohen et al. 1995; Grosholz and Ruiz 1995 1993 1993-01-01 Black Point Def 38.0667 -122.3833
2525 Grosholz and Ruiz 1995; Wasson et al. 2001 1993 1993-10-19 Elkhorn Slough Def 36.8058 -121.7892
2526 Miller 1996; Grosholz and Ruiz 1995 1993 1993-01-01 Bolinas Lagoon Def 37.9183 -122.6800
2528 Miller 1996; Ruiz et al. 1998 1993 1993-06-04 Bodega Harbor Def 38.3236 -123.0467
2530 Miller 1996; Ruiz et al. 1998 1995 1995-06-24 Arcata Bay (Humboldt Bay) Def 40.8022 -124.1625
2531 Grozholz and Ruiz 1998 1997 1997-01-01 Coos Bay Def 43.3988 -124.2222
2532 Washington Department of Fish and Wildlife 1999 1998 1998-01-01 Newport Def 44.6206 -124.0369
2533 Washington Department of Fish and Wildlife 1999 1998 1998-01-01 Willapa Bay Def 46.5538 -124.0172
2534 Washington Department of Fish and Wildlife 1999 1998 1998-01-01 Grays Harbor Def 46.9508 -124.0497
2535 Fisheries and Oceans Canada 2000 1999 1999-01-01 Victoria Def 48.4333 -123.3500
2536 Fisheries and Oceans Canada 2000 1999 1999-01-01 Tofino (Vancouver Island) Def 49.1333 -125.9000
2537 Fisheries and Oceans Canada 2000 1999 1999-01-01 Vancouver Island Def 48.8333 -125.2500
2538 Bryant 1909; Glude 1955; Almaca 1963 1872 1872-01-01 Provincetown Def 42.0583 -70.1792
2778 Audet et al. 2003 1953 1953-01-01 Sandy Cove Def 44.6000 -65.7500
2779 Audet et al. 2003 1956 1956-01-01 Cape Forchu Def 43.8000 -66.1667
2780 Audet et al. 2003 1960 1960-01-01 Lockeport Def 43.7000 -65.1167
2781 Audet et al. 2003 1983 1983-01-01 Tor Bay Def 45.2167 -61.3667
2782 Audet et al. 2003 1994 1994-01-01 Margaree Harbour Def 46.4333 -61.1000
2783 Audet et al. 2003 1997 1997-01-01 Antigonish Def 45.6167 -61.9667
2784 Audet et al. 2003 1998 1998-01-01 Merigomish Def 45.6167 -62.4167
2785 Audet et al. 2003 2001 2001-01-01 Wallace Bay Def 45.8333 -63.5833
2786 Audet et al. 2003 2002 2002-01-01 Port Elgin Def 46.0500 -64.1000
2787 Audet et al. 2003 1998 1998-01-01 Murray Harbour/ Def 46.0167 -62.5333
2788 Audet et al. 2003 1997 1997-01-01 Cardigan Def 46.2333 -62.6167
2789 Audet et al. 2003 2001 2001-01-01 Savage Harbour Def 46.4167 -62.7000
2790 Audet et al. 2003 2000 2000-01-01 Malpeque Bay Def 46.5000 -63.7833
2791 Audet et al. 2003 1999 1999-01-01 Vernon Def 46.1833 -62.8833
2792 Audet et al. 2003 2000 2000-01-01 Charlottetown Def 46.2333 -63.1333
2793 Audet et al. 2003 2001 2001-01-01 Victoria Def 46.2167 -63.4833
3498 Curley et al. 1974 1970 1970-01-01 Mount Hope Bay Def 41.6833 -71.2167
3499 Bryant 1906 1902 1902-01-01 Manomet Point Def 41.9267 -70.5394
3500 Bryant 1906 1902 1902-01-01 Lynn Def 42.4667 -70.9500
3501 Simard et al. 2005 2004 2004-01-01 Madeleine Islands Def 47.5250 -61.6944
3502 Bryant 1906 1902 1902-01-01 Ipswich Def 42.6792 -70.8417
3503 Bryant 1906 1902 1902-01-01 Portland Def 43.6614 -70.2558
3504 Glude 1955 1907 1907-01-01 Boothbay Harbor Def 43.8493 -69.6320
3505 Glude 1955 1907 1907-01-01 Tenants Harbor Def 43.9672 -69.2086
3506 Glude 1955 1912 1912-01-01 Friendship Def 43.9836 -69.3344
3507 Glude 1955 1930 1930-01-01 Brooklin Def 44.2661 -68.5697
3508 Glude 1955 1937 1937-01-01 Bass Harbor Def 44.2400 -68.3444
3509 Glude 1955 1951 1951-06-01 Jonesport Def 44.5983 -67.5508
3511 MIT Sea Grant 2003 2003 2003-08-03 New Castle Def 43.0722 -70.7167
3512 MIT Sea Grant 2003 2003 2003-08-03 Hampton Def 42.9375 -70.8394
3513 MIT Sea Grant 2003 2003 2003-07-03 Halibut Point, Def 42.6917 -70.6292
3514 MIT Sea Grant 2003 2000 2000-08-08 Beverly Def 42.5583 -70.8806
3515 MIT Sea Grant 2003 2000 2000-08-09 Bay Pointe Marina, Quincy Def 42.2528 -71.0028
3516 MIT Sea Grant 2003 2000 2000-08-09 Duxbury Def 42.0417 -70.6728
3517 MIT Sea Grant 2003 2000 2000-08-14 India Point, Providence Def 41.8169 -71.3900
3518 MIT Sea Grant 2003 2000 2000-08-18 Warwick Def 41.6839 -71.3917
3519 MIT Sea Grant 2003 2000 2000-08-15 Roger Williams University, Bristol Def 41.6769 -71.2667
3520 MIT Sea Grant 2003 2000 2000-08-17 Prudence Island Def 41.6422 -71.3419
3521 MIT Sea Grant 2003 2000 2000-08-16 North Kingstown Def 41.6237 -71.4126
3522 MIT Sea Grant 2003 2000 2000-08-15 Wickford Marina Def 41.5739 -71.4619
3523 MIT Sea Grant 2003 2000 2000-08-11 Westport Def 41.5125 -71.0894
3524 MIT Sea Grant 2003 2000 2000-08-16 Fort Getty (Beaverhead) Def 41.4937 -71.3973
3525 MIT Sea Grant 2003 2003 2003-08-07 Brewer Yacht Yard, Mystic Def 41.3542 -71.9669
3526 MIT Sea Grant 2003 2003 2003-08-08 Milford Yacht Club, Milford Def 41.2222 -73.0569
3527 MIT Sea Grant 2003 2003 2003-08-07 Stirling Harbor Shipyard, Greenport Def 41.1033 -72.3597
3528 MIT Sea Grant 2003 2003 2003-08-08 Long Island Sound Def 41.0533 -73.5392
3529 MIT Sea Grant 2003 2003 2003-08-09 Great Kills Park, Staten Island Def 40.5481 -74.1267
3530 de Rivera et al. 2005b 2003 2003-07-01 Sinepuxent Bay Def 38.1300 -75.2800
3531 de Rivera et al. 2005b 2003 2003-07-01 Cape May Def 39.0300 -74.9200
3532 deRivera et al. 2005b 2003 2003-07-01 Great Bay Def 39.5300 -74.3300
3533 de Rivera et al. 2005b 2003 2003-07-01 None Def 41.4000 -71.5100
3534 de Rivera et al. 2005b 2003 2003-07-01 Falmouth Def 41.5700 -70.5300
3535 de Rivera et al. 2005b 2003 2003-07-01 Eastham Def 41.8100 -69.9600
3536 de Rivera et al. 2005b 2003 2003-07-01 Biddeford Def 43.4500 -70.3500
3538 Cohen et al. 1995 1992 1992-03-01 Hayward Def 37.6689 -122.0797
3539 Cohen et al. 1995 1992 1992-03-01 Foster City Lagoon Def 37.5586 -122.2700
3540 Cohen et al. 1995 1992 1992-05-01 Crab Cove, Crown Beach, and Bay Farm Island Def 37.7311 -122.2258
3542 Cohen et al. 1995 1992 1992-07-01 Berkeley Aquatic Par Def 37.8569 -122.2978
3544 Cohen et al. 1995 1992 1992-12-01 Dumbarton Bridge Def 37.5053 -122.1183
3546 Cohen et al. 1995 1993 1993-03-01 Richardson Bay Def 37.8697 -122.4850
3547 Cohen et al. 1995 1993 1993-03-01 China Camp Def 38.0008 -122.4606
3548 Cohen et al. 1995 1993 1993-03-01 Point Pinole Def 38.0121 -122.3666
3549 Cohen et al. 1995 1994 1994-02-01 Berkeley Marina Def 37.8681 -122.3153
3550 ICES Committee on the Marine Environment 2004 2004 2000-07-20 Bligh Island Def 49.6542 -126.5208
3551 ICES Committee on the Marine Environment 2004 2001 2001-08-15 Vancouver Island Def 49.9500 -126.9000
3552 ICES Committee on the Marine Environment 2004 2001 2001-06-01 Port Eliza Def 49.8833 -127.0167
3553 ICES Committee on the Marine Environment 2004 2003 2003-07-11 Klitsis Beach Def 49.9333 -126.9000
3554 U.S. National Museum of Natural History 2002 1983 1983-01-01 Zeebrugge Native 51.3000 3.2000
3555 U.S. National Museum of Natural History 2002 1974 1974-11-09 Faro Native 37.0167 -7.9333
3556 U.S. National Museum of Natural History 2002 1974 1974-10-29 Bahia de Cadiz Native 36.5475 -6.2692
3557 U.S. National Museum of Natural History 2002 1974 1974-10-22 Ksar Es Seghir Native 35.8475 -5.5631
3558 U.S. National Museum of Natural History 2002 1974 1974-10-20 Atlantic Ocean Native 34.0253 -6.8361
3559 U.S. National Museum of Natural History 2002 1992 1992-08-28 Golfe de St. Malo Native 48.8667 -1.8333
3560 Rathbun 1930 1923 1923-01-01 Chatham Native 51.3833 0.5167
3561 Rathbun 1930 1923 1923-01-01 Cowes Native 50.7667 -1.3000
3562 Rathbun 1930 1923 1923-01-01 Jersey Native 50.2000 -2.2000
3563 Rathbun 1930 1923 1923-01-01 Ostende Native 51.2167 2.9167
3564 Rathbun 1930 1930 1930-01-01 Helgoland Island Native 54.2000 7.8833
3565 Roman and Palumbi 2004 2002 2002-08-01 Seltjarnarnes Native 64.1333 -21.9333
3566 Roman and Palumbi 2004 2002 2002-09-01 Torshavn, Faero Islands Native 62.0000 -6.8000
3567 Roman and Palumbi 2004 2001 2001-08-01 Trondheim Native 63.4167 10.4167
3569 Roman and Palumbi 2004 2001 2001-09-01 Mongstadt Native 60.8000 5.0000
3570 Roman and Palumbi 2004 2001 2001-09-01 Oslo Native 59.9167 10.7500
3571 Roman and Palumbi 2004 2001 2001-08-01 Göteborg Native 57.7167 11.9667
3572 Roman and Palumbi 2004 2001 2001-08-01 Bremerhaven Native 53.5500 8.5833
3573 Roman and Palumbi 2004 2001 2001-08-01 Hoek Van Holland Native 52.0000 4.2000
3574 Roman and Palumbi 2004 2001 2001-08-01 Fowey Native 50.3333 -4.6333
3575 Roman and Palumbi 2004 1999 1999-07-01 Roscoff Native 48.7333 -3.9833
3576 Roman and Palumbi 2004 2001 2001-09-01 Bilbao Native 43.2500 -2.9667
3577 Roman and Palumbi 2004 2001 2001-09-01 Aveiro Native 40.6333 -8.6500
3578 Roman and Palumbi 2004 2001 2001-09-01 Cadiz Native 36.5336 -6.2994
3579 Clark et al. 2001 1969 1969-07-08 Mainland, Shetlands Native 60.1500 -1.1500
3580 Clark et al. 2001 2001 1968-09-21 Loch Torridon Native 57.5833 -5.7667
3581 Clark et al. 2001 1996 1996-11-01 Fyn (Island) Native 55.1500 10.0833
3582 Clark et al. 2001 1970 1970-05-20 Menai Bridge Native 53.2167 -4.1500
3583 Clark et al. 2001 2001 1970-07-01 Coulagh Bay Native 51.7036 -10.0067
3584 Clark et al. 2001 1996 1996-11-21 North Sea Native 52.9333 1.3000
3585 Clark et al. 2001 1996 1996-09-29 West Runton Native 52.9333 1.2500
3586 Clark et al. 2001 1970 1970-06-01 Fawley, Native 50.8167 -1.3500
3587 Clark et al. 2001 1997 1997-01-01 Fort Euk, near Rochefort Native 46.0033 -1.1250
3588 Clark et al. 2001 1977 1977-04-01 Porto Native 41.1500 -8.6167
3589 Clark et al. 2001 1997 1997-01-01 Canal de Mira, Ria de Aveiro Native 40.6333 -8.7333
3590 Clark et al. 2001 1986 1986-05-01 Mira Native 40.4333 -8.7333
3591 Clark et al. 2001 1984 1984-02-26 Villa Nova de Milfonte Native 37.8000 -8.8000
3592 Clark et al. 2001 1997 1997-09-14 Palmones Estuary, Algeceiras Bay Native 36.1667 -5.4533
3593 Clark et al. 2001 1997 1997-09-15 Europa Point, Gibraltar Native 36.1106 -5.3458
3594 Clark et al. 2001 1997 1997-09-15 Sandy Bay, Strait of Gibraltar Native 36.1167 -5.3333
3595 University of Tromso 2003 2003 2003-05-17 Sommarøy Native 69.6467 18.0333
3596 University of Tromso 2003 1992 1992-08-01 Oostduinkerke Native 51.5333 3.9417
3597 University of Tromso 2003 2003 2003-04-23 Kattendijke Native 51.5333 3.9417
3600 Christiansen 1969 1969 1969-01-01 Kvaenangen Native 69.9333 21.7167
3601 Dries and Adelung 1982 1982 1982-01-01 Fredericia Native 55.5833 9.7667
3602 Dries and Adelung 1982 1982 1982-01-01 Stige (Fyn) Native 55.4333 10.4167
3603 Dries and Adelung 1982 1982 1982-01-01 Svendborg (Fyn) Native 55.0500 10.6167
3604 Dries and Adelung 1982 1982 1982-01-01 Abenra Native 55.0333 9.4333
3605 Dries and Adelung 1982 1982 1982-01-01 Kappeln Native 54.6667 9.9333
3606 Dries and Adelung 1982 1982 1982-01-01 Kiel Native 54.3333 10.1333
3607 Dries and Adelung 1982 1982 1982-01-01 Neustadt Native 54.1000 10.8167
3608 Dries and Adelung 1982 1982 1982-01-01 Wismar Native 53.9000 11.4667
3609 Dries and Adelung 1982 1982 1982-01-01 Darss Native 54.4333 12.5500
3610 Dries and Adelung 1982 1882 1982-01-01 Gedser Odde Native 54.5667 11.9833
3611 Dries and Adelung 1982 1982 1982-01-01 Dries and Adelung Native 55.6667 12.5833
3612 Geller et al. 1997 1997 1997-01-01 Rio de Betanzos Native 37.0000 -6.0000
3613 Geller et al. 1997 1997 1997-01-01 Cadiz Native 36.0000 -6.0000
3614 Geller et al. 1997 1997 1997-01-01 Texel and Den Helder Native 53.0000 5.0000
3615 Geller et al. 1997 1997 1997-01-01 Isle of Wight Native 51.0000 -1.0000
3616 Poulsen 1922 1922 1922-01-01 Bornholm Native 55.1667 15.0000
3617 Poulsen 1922 1922 1922-01-01 Randers Fjord Native 56.5583 10.2394
3618 McVean 1976 1976 1976-01-01 Whitby Native 54.4867 -0.6306
3619 Milne and Dunnet 1972 1972 1972-01-01 Newburgh Native 57.3000 -2.0000
3620 Monod 1956 1956 1956-01-01 Nouadhibou Native 20.9000 -17.0667
3625 Carlton and Cohen 2003 1998 1998-01-01 Netarts Bay Def 45.4025 -123.9444
3626 Carlton and Cohen 2003 1998 1998-01-01 Tillamook Bay Def 45.5131 -123.9153
3627 Fulton and Grant 1902 1900 1900-01-01 Port Phillip Bay Def -38.1500 144.8667
3628 Ahyong 2003 1891 1891-01-01 Sydney Def -33.8500 151.2500
3629 Thresher et al. 2003 1998 1998-01-01 Queenscliff Def -38.2667 144.6500
3630 Thresher et al. 2003 1998 1998-01-01 Geelong Def -38.1583 144.3500
3631 Thresher et al. 2003 1998 1998-01-01 Point Wilson Def -38.0833 144.5000
3632 Thresher et al. 2003 1998 1998-01-01 Point Cook Def -37.9167 144.8000
3633 Thresher et al. 2003 1998 1998-01-01 Melbourne Def -37.8167 144.9667
3634 Thresher et al. 2003 1998 1998-01-01 Portsea Def -38.3167 144.7167
3635 Thresher et al. 2003 1998 1998-01-01 Quail Island Def -38.2333 145.2833
3636 Thresher et al. 2003 1998 1998-01-01 Wonthaggi Def -38.6167 145.5333
3637 Thresher et al. 2003 1998 1998-01-01 Welshpool Def -38.6667 146.4333
3638 Thresher et al. 2003 1998 1998-01-01 Port Albert Def -38.6667 146.6833
3639 Thresher et al. 2003 1998 1998-01-01 Woodside Def -38.5167 146.8667
3641 Thresher et al. 2003 1998 1998-01-01 Disaster Bay Def -37.2833 150.0000
3642 Thresher et al. 2003 1971 1971-01-01 Twofold Bay Def -37.1000 149.9167
3643 Ahyong 2005 1993 1993-01-01 Bermagui Def -36.4167 150.0500
3644 Ahyong 2005 1996 1996-01-01 Narooma Def -36.2167 150.0500
3645 Ahyong 2005 1985 1985-11-01 Durras Def -35.6667 150.3000
3646 Ahyong 2005 1985 1985-11-01 Burrill Lake Def -35.3833 150.4500
3647 Ahyong 2005 1992 1992-04-01 Lake Conjola Def -35.2667 150.5000
3648 Ahyong 2005 1988 1988-10-27 Plantation Point Def -35.0002 150.7483
3649 Ahyong 2005 1978 1978-03-01 Botany Bay Def -34.0000 151.2000
3650 Furlani 1996 1976 1976-01-01 Adelaide Def -34.9333 138.6000
3651 Thresher et al. 2003 1998 1998-01-01 Willunga Def -35.2833 138.5500
3653 Thresher et al. 2003 1993 1993-01-01 Georges Bay Def -41.3128 148.2900
3654 Thresher et al. 2003 1998 1998-01-01 Stanley Def -40.7667 145.3000
3655 Thresher et al. 2003 1998 1998-01-01 Wynyard Def -41.0000 145.7167
3656 Thresher et al. 2003 1998 1998-01-01 Burnie Def -41.0667 145.9167
3657 Thresher et al. 2003 1998 1998-01-01 Ulverstone Def -41.1500 146.1667
3658 Thresher et al. 2003 1998 1998-01-01 Devonport Def -41.1667 146.3500
3659 Thresher et al. 2003 1998 1998-01-01 Cape Portland Def -40.7500 147.9500
3660 Thresher et al. 2003 1998 1998-01-01 St. Helens Def -41.3203 148.2389
3661 Thresher et al. 2003 1998 1998-01-01 St. Marys Def -41.5792 148.1733
3662 Thresher et al. 2003 1998 1998-01-01 Freycinet National Park Def -42.2167 148.3000
3663 Thresher et al. 2003 1998 1998-01-01 Triabunna Def -42.5069 147.9103
3664 Thresher et al. 2003 1998 1998-01-01 Blackman Bay Def -43.0167 147.3167
3665 Joska and Branch 1986; Griffiths et al. 1992 1983 1983-01-01 Cape Town Def -33.8833 18.4500
3666 Griffiths et al. 1992 1984 1984-01-01 Bloubergstrand Def -33.8000 18.4500
3667 Griffiths et al. 1992 1990 1990-01-01 Camps Bay Def -33.9500 18.3833
3668 Robinson et al. 2005 2005 2005-01-01 Cape Town Def -34.0667 18.3667
3669 Le Roux 1992; Robinson et al. 2004 1990 1990-01-01 Saldanha Bay Def -33.0833 18.0167
3670 Carlton and Cohen 2003 1984 1984-01-01 Tokyo Bay Def 35.4169 139.7836
3671 Carlton and Cohen 2003 1999 1999-01-01 Sagami Bay Def 35.3333 139.2500
3672 Carlton and Cohen 2003 1999 1999-01-01 Osaka Bay Def 34.5000 135.3000
3673 Carlton and Cohen 2003 1999 1999-01-01 Dokai Bay Def 33.9000 130.9000
3682 Hidalgo et al. 2005 2003 2003-11-01 Caleta Carolina, Camerones Bay Def -44.9000 -65.6000
3683 Hidalgo et al. 2005 2004 2004-01-01 Caleta Sara, Camerones Bay Def -44.9000 -65.5667
4021 Vader 1979 1976 1976-06-01 Loppa Native 70.3333 21.4500
4022 Vader 1979 1976 1976-06-01 Fuglen Native 70.6500 21.9667
4023 Vader 1979 1977 1977-07-01 Rolvsøya Native 70.9978 24.0236
4024 Vader 1979 1977 1977-08-01 Russeluft Native 70.0258 23.3700
4025 Vader 1979 1977 1977-07-01 Mehavn Native 71.0333 27.8500
4026 Alamaca 1960 1960 1960-01-01 Ceuta (Spanish enclave, Morocco) Native 35.8903 -5.3075
4027 Alamaca 1960 1960 1960-01-01 Santander, Native 43.4647 -3.8044
4028 Alamaca 1960 1960 1960-01-01 San Sebastian, Native 43.3167 -1.9833
4029 Alamaca 1960 1960 1960-01-01 Biarritz Native 43.4833 -1.5667
4365 Graham Gillespie, 2006, personal communication 2006 2006-07-01 Kyuquot Def 50.0333 -127.2200
4707 CBC News 2007 2007 2007-09-01 Placentia Bay Def 47.8600 -54.1030
6760 Museum of Comparative Zoology 2009 1904 1904-01-01 Chatham Def 41.6821 -69.9597
6761 Museum of Comparative Zoology 2009 1903 1903-04-01 Waquoit Def 41.5501 -70.5278
6776 MIT Sea Grant 2008 2007 2007-07-27 Wells Def 43.3215 -70.5595
6777 MIT Sea Grant 2008) 2007 2007-07-30 Wayfarer Marina, Camden Def 44.2104 -69.0528
6844 Klassen and Locke 2007 2007 2007-01-01 Winter Harbour Def 50.5330 -128.0000
6845 Klassen and Locke 2007 2007 2007-01-01 Brooks Bay Def 50.3000 -127.8330
6846 Klassen and Locke 2007 2007 2007-08-01 Black River Def 47.8800 -54.1690
6847 Klassen and Locke 2007 2007 2007-08-01 Southern Harbour Def 47.7140 -53.9690
6848 Klassen and Locke 200 2007 2007-08-01 Davis Cove Def 47.6350 -54.3400
6864 2010, Fisheries and Oceans 2011 2010 2011-01-01 Fox Harbour Def 47.3194 -53.9150
6865 Fisheries and Oceans 2011 2010 2010-01-01 Spanish Room Def 47.1911 -55.0800
6866 Fisheries and Oceans Canada 2011 2008 2008-01-01 Stephenville Def 48.5476 -58.5476
6867 Fisheries and Oceans Canada 2011 2010 2010-01-01 Rocky Harbour Def 49.5533 -57.9314
6868 Fisheries and Oceans Canada 2011 2011 2011-01-01 Cabot Strait Def 47.6142 -58.8701
6912 Matheson and Gagnon 2012 2009 2009-05-15 Petty Cove Def 47.4680 -52.7038
31803 Cohen and Carlton 1995 1989 1989-01-01 Estero de Americano Def 38.3081 -122.9845
761909 nicolejnk on i-Naturalis 2019 Caleta Olivia Def -46.4600 -67.4900
768493 0 near Seabeck/WA/Nick's Lagoon, Hood Canal (5/2022, USGS Nonindigenous Aquatic Species Database, 47.6409° N, 122.8286° W) Def 47.6400 -122.8300
768495 Miller 2022 2022 Annette Island, Meetakatla Indian Community, Ketchikan area/AK/Bostwick Inlet-Frontal Nichols Passage (7/22/2022, Miller 2022, 55.1288° N, 131.5745° W,) Def 55.1300 -131.5700

References

Feitosa de Padua, Stella Maris; Botter-Carvalho. Monica Lucia; Gomes. Paula Braga; Silva de Oliveira, Camilla; Pacheco dos Santos. Jose´ Carlos; Pe (2022) The alien octocoral Carijoa riisei is a biogenic substrate multiplier in artificial Brazilian shipwrecks, Aquatic Ecology 56: 183–200
doi.org/10.1007/s10452-021-09908-8

Fukuda, Tomoko; Kato, Yukie; Sato, Hiroyuki; Taran , Aleksan; r A. Barkalov, Vyacheslav Yu.; Takahashi, Hideki (2018) Naturalization of Cakile edentula (Brassicaceae) on the Beaches of Kunashiri and Etorofu Islands ― The First Record for the Species from the Kuril Islands, Japanese Journal of Malacology 88: 124-128

Ahyong, Shane T. (2005) Range extension of two invasive crab species in eastern Australia: Carcinus maenas and Pyromaia tuberculata, Marine Pollution Bulletin 50: 460-462

Ahyong, Shane T.; Wilkens, Serena L. (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 451-485

Allee, W. C. (1923) Studies in marine ecology: I. The distribution of common littoral invertebrates of the Woods Hole region, Biological Bulletin 44(4): 167-191

Allen, F. E. (1953) Distribution of marine invertebrates by ships, Australian Journal of Marine and Freshwater Research 4(2): 307-316

Almaca, C. (1962) Sur la distribution geographique du genre Carcinus Leach (Crust. Dec. Brach.), Revista da Faculdade de Ciências, Universidade de Lisboa, series 2^C 10(1): 109-113

Almaca, C. (1963) Sur le probleme de l'origine de Carcinus maenas (L.) du littoral Americain., Revista da Faculdade de Ciências, Universidade de Lisboa, series 2^C 11(2): 121-136

Almaca, Carlos (1960) Variabilidade de alguns caracteres usados na taxonomia do Gen. Carcinus Leach., Revista da Faculdade de Ciéncias de Lisboa 7: 137-153

Almeida, Maria Joao; Flores, Augusto A.V.; Queiroga, Henrique (2008) Effect of crab size and habitat type on the locomotory activity of juvenile shore crabs, Carcinus maenas., Estuarine, Coastal and Shelf Science 80: 509-516

Aronson, Richard B.; Frederich, Markus; Price, Rick; Thatje, Sven (2015) Prospects for the return of shell-crushing crabs to Antarctica, Journal of Biogeography 42: published online

Associated Press 11/24/2011 St Maarten nixes plan to promote lionfish as food after tests show some meat tainted. <missing URL>



Audet, Dominique; Davis, Derek S.; Miron, Gilles; Moriyasu, Mikio; Benhalima, Khadra; Campbell, Robert (2003) Geographical expansion of a nonindigenous crab, Carcinus maenas along the Nova Scotian shore into the Southwestern Gulf of St. Lawrence, Canada., Journal of Shellfish Research 22(1): 255-262

Bagley, M. J., Geller, J. B. (2000) Microsatellite DNA analysis of native and invading populations of European Green Crabs., In: (Eds.) . , Cambridge. Pp. <missing location>

Bakus, Gerald J.; Green, Karen D. (1987) The Distribution of Marine Sponges Collected from the 1976-1978 Bureau of Land Management Southern California Bight Program, Bulletin of the Southern California Academy of Sciences 86(2): 57-88

Baldridge, Ashley K.; Smith, L. David (2008) Temperature constraints on phenotypic plasticity explain biogeographic patterns in predator trophic morphology., Marine Ecology Progress Series 365: 25-34

Baldwin, Andy; Leason, Diane (2016) Potential Ecological impacts of Emerald Ash Borer on Maryland's Eastern Shore, In: None(Eds.) None. , <missing place>. Pp. <missing location>

Banas, Neil S.; McDonald, P. Sean; Armstrong, David A. (2009) Green crab larval retention in Willapa Bay, Washington: an intensive Lagrangian modeling approach, Estuaries and Coasts 32: 893-905

Bandeira-Pedrosa, Maria Elizabeth; Pereira Sonia M. B.; Oliveira Eurico C. (2004) Taxonomy and distribution of the green algal genus Halimeda (Bryopsidales, Chlorophyta) in Brazil, Revista Brasileira de Botânica 27(2): 363-377

Barnes, H.; Barnes, Margaret (1972) Some Cirripedes of the French Atlantic Coast., Journal of Experimental Marine Biology and Ecology 8: 187-194

Berrill, M. (1982) The life cycle of the green crab Carcinus maenas at the northern end of its range, Journal of Crustacean Biology 2(1): 31-39

Bertness, Mark D.; Leonard, George H.; Levine, Jonathan M. Schmidt Paul R.; Ingraham, Aubrey O. (1999) Testing the relative contribution of positive and negative interactions in rocky intertidal communities., Ecology 80(8): 2711-2726

Bertness, Mark D.; Trussell, Geoffrey C.; Ewanchuk, Patrick J.; Silliman, Brian R. (2002) Do alternate stable community states exist in the Gulf of Maine rocky intertidal zone?, Ecology 83(12): 3434-3448

Bertness, Mark D.; Trussell, Geoffrey C.; Ewanchuk, Patrick J.; Silliman, Brian R.; Crain, Caitlin Mullan (2004) Consumer-controlled community states on Gulf of Maine rocky shores, Ecology 85(5): 1321-1331

Blakeslee, A. M. H.; McKenzie, C. H.; Darling, J. A.; Byers, J. E.; Pringle, J. M.; Roman, J. (2010) A hitchhiker’s guide to the Maritimes: anthropogenic transport facilitates long-distance dispersal of an invasive marine crab to Newfoundland, Diversity and Distributions 16: 879-891

Blakeslee, April M. H.; Keogh, Carolyn L.; Byers, James E.; Kuris, Armand M. Lafferty, Kevin D.; Torchin, Mark E. (2009) Differential escape from parasites by two competing introduced crabs, Marine Ecology Progress Series 393: 83-96

Blakeslee, April M. H.; Keogh, Carolyn L.; Fowler, Amy E.; Griffen, Blaine D. (2015) Assessing the effects of trematode infection on invasive green crabs in eastern North America, PLOS ONE Published online: <missing location>

Blakeway, Raven D.; Fogg, Alexander Q.; Johnston, Michelle A.; Rooker, Jay R.; Jones, Glenn A. (2022) Key life history attributes and removal efforts of Iinvasive lionfish (Pterois volitans) in the Flower Garden Banks National Marine Sanctuary, northwestern Gulf of Mexico, Frontiers in Marine Science 9(774407): Published online

Bloch. Philip; Novak, Grant (2011) The 2011 International Conference on Ecology & Transportation, International Conference on Ecology & Transportation, <missing place>. Pp. 400-410

Boyd, Milton J.; Mulligan, Tim J; Shaughnessy, Frank J. (2002) <missing title>, California Department of Fish and Game, Sacramento. Pp. 1-118

Bravo, Monica A.; Cameron, Beth; Metaxas, Anna (2007) Salinity tolerance in the early larval stages of Carcinus maenas (Decapoda, Brachyura), a recent invader of the Bras D'Or Lakes, Nova Scotia, Crustaceana 80(4): 475-490

Breen, Erin; Metaxas, Anna (2008) A comparison of predation rates by non-indigenous and indigenous crabs (juvenile Carcinus maenas, juvenile Cancer irroratus, and adult Dyspanopeus sayi) in laboratory and field experiments., Estuaries and Coasts 31: 728-737

Breen, Erin; Metaxas, Anna (2009) Effects of juvenile non-indigenous Carcinus maenas on the growth and condition of juvenile Cancer irroratus., Journal of Experimental Marine Biology and Ecology 377: 12-19

Breen, Erin; Metaxas, Anna (2012) Predicting the interactions between 'ecologically equivalent' indigenous and nonindigenous brachyurans, Canadian Journal of Fisheries and Aquatic Science 69: 983-995

Bremec, Claudia S.; Giberto, Diego A. (2004) New records of two species of Sabellaria (Polychaeta: Sabellariidae) from the Argentinean Biogeographic Province, Revista de Biologia Marina y Oceanografia 39(2): 101-105

Brenchley, G. A. (1982) Predation on encapsulated larvae by adults: Effects of introduced species on the gastropod Ilyanassa obsoleta, Marine Ecology Progress Series 9(255-262): <missing location>

Brockerhoff, Annette; McLay, Colin (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht. Pp. 27-106

Broekhuysen, G. J. Jr. (1936) On the development, growth, and distribution of Carcinides maenas (L.), Archives Neerlandaises de Zoologie 2: 237-399

Bryant, O. (1906) Recent extension of the range of the green crab, The American Naturalist 40: 382-383

Burden, Catriona T.; Stow, Adam J.; Hoggard, Stephen J.; Coleman, Melinda A.; Bishop, Melanie J. (2014) Genetic structure of Carcinus maenas in southeast Australia, Marine Ecology Progress Series 500: 139-147

Burfeind, Dana D.; Pitt, Kylie A.; Connolly, Rod M.; Byers, James E. (2012) Performance of non-native species within marine reserves, Biological Invasions published online: <missing location>

Byers, James E.; Noonburg, Erik G. (2003) Scale dependent effects of biotic resistence to biological invasion., Ecology 84(6): 1428-1433

Cameron, Beth; Metaxas, Anna (2005) Invasive green crab, Carcinus maenas, on the Atlantic coast and in the Bras d'Or Lakes of Nova Scotia, Canada: larval supply and recruitment, Journal of the Marine Biological Association of the United Kingdom 85: 847-855

Canadian Broadcasting Corporation 8/27/2007 Invasive crab found in N. L. waters. <missing URL>



Cárdenas-Calle, Maritsa and 11 authors (2021) Invasion and current distribution of the octocoral Carijoa riisei (Duchassaing & Michelotti, 1860) in the Ecuadorian coast (Eastern Tropical Pacific), Biological Invasions 16(1): 62-76

Carlton, James T.; Cohen, Andrew N. (2003) Episodic global dispersal in shallow water marine organisms: the case history of the European shore crabs, Carcinus maenas and C. aestuarii, Journal of Biogeography 30: 1809-1820

Carlton, James T.; Newman, William A.; Pitombo, Fábio Bettini (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht. Pp. 159-213

Chaouti, Abdellatif; Belattmania, Zahira; Nadri, Amal; Serrão, Ester A.; Encarnação, Joao; Teodósio, Alexandra; Rean, Abdeltif; BSabour, rahim (2022) The invasive Atlantic blue crab Callinectes sapidus Rathbun, 1896 expands its distributional range southward to Atlantic African shores: first records along the Atlantic coast of Morocco, BioInvasions Records <missing volume>(in press): In press

Christiansen, Marit E. (1969) <missing title>, Universitetsforlaget, Oslo. Pp. <missing location>

Clark, Paul F.: Neale , Michael; Rainbow, Phillip S. (2001) A morphometric analysis of regional variation in Carcinus Leach 1812 (Brachyura:Portununidae:Carcininae) with particular reference fo the status of the two species C. maenas (Linnaeus 1758) and C. aestuarii Nardo 1847., Journal of Crustacean Biology 21(1): 288-303

Cohen, A. N. and 11 authors (2005) Rapid assessment survey for exotic organisms in southern California bays and harbors, and abundance in port and non-port areas., Biological Invasions 7: 995-1002

Cohen, A.N.; Carlton, J.T.; Fountain, M.C. (1995) Introduction, dispersal and potential impacts of the green crab Carcinus maenas in San Francisco Bay, California., Marine Biology 122: 225-237

Cohen, Andrew N. and 10 authors (2005) <missing title>, San Francisco Estuary Institute, Oakland CA. Pp. <missing location>

Cohen, Andrew N.; Carlton, James T. (1995) Nonindigenous aquatic species in a United States estuary: a case study of the biological invasions of the San Francisco Bay and Delta, U.S. Fish and Wildlife Service and National Sea Grant College Program (Connecticut Sea Grant), Washington DC, Silver Spring MD.. Pp. <missing location>

Compton, T. J.; Leathwick, J. R.; Inglis, G. J. (2010) Thermogeography predicts the potential global range of the invasive European green crab (Carcinus maenas), Diversity and Distributions 16: 243-255

Corbett, James J.; Trussell, Geoffrey C. (2023) Local and regional geographic variation in inducible defenses, Ecology 105(1): Published online
DOI: 10.1002/ecy.4207

Cordone, Georgina; Lozada, Mariana; Vilacoba, Elisabet; Thalinger, Bettina; Bigatti; Lijtmaer, Dar?o A.; Steinke, Dirk; Galvan David E. (2022) Metabarcoding, direct stomach observation and stable isotope analysis reveal a highly diverse diet for the invasive green crab in Atlantic Patagonia, Biological Invasions 24: 505–526

Cordone, Georgina; Galván, David E.; Momo, Fernando R. (2023) Impacts of an invasion by green crab Carcinus maenas on the intertidal food web of a Patagonian rocky shore, Argentina, Marine Ecology Progress Series 713: 97-115
https://doi.org/10.3354/meps14336

Cordone,,Georgina; and 7 authors (2021) Metabarcoding, direct stomach observation and stable isotope analysis reveal a highly diverse diet or the invasive green crab in Atlantic Patagonia, Biological Invasions Published online: <missing location>

Corsini- Foka, Maria and 8 authors (2021) Invasive portunid crabs in Libyan waters: first record of the Atlantic blue crab Callinectes sapidus Rathbun, 1896 and range expansion of the swimming blue crab Portunus segnis (Forskål, 1775), BioInvasiob=ns Records 10: In press

Coutts, Ashley D. M.; Moore, Kirrily M.; Hewitt, Chad L. (2003) Ships' sea-chests: an overlooked transfer mechanism for non-indigenous marine species., Marine Pollution Bulletin 46: 1504-1515

Crafton, R. Eliot (2015) Modeling invasion risk for coastal marine species utilizing environmental and transport vector data, Hydrobiologia 746: 349-362

Crothers, J. H. (1968) The biology of the shore crab Carcinus maenas (L.) 2. The life of the adult crab., Field Studies 2: 579-614

Crothers, J.H. (1967) The biology of the shore crab Carcinus maenas (L.) 1. The background- anatomy, growth and life history, Field Studies 2: 407-434

Curley, John R., Lawton, Robert P., Chadwick, David L., Reback, Kenneth, Hickey, John M. (1974) A study of the marine resources of the Taunton River and Mount Hope Bay, Massachusetts Department of Natural Resources, Division of Marine Fisheries 15: 1-37

Currie, D. R.; McArthur, M. A.; Cohen, B. F. (1999) Exotic Marine Pests in the Port of Geelong, Victoria, In: Hewitt, Campbell, Thresher & Martin(Eds.) Marine Biological Invasions of Port Phillip Bay, Victoria. , Hobart, Tasmania. Pp. 227-246

Danziger, Ariella; Frederich, Markus (2022) Challenges in eDNA detection of the invasive European green crab, Carcinus maenas, Biological Invasions <missing volume>: https://link.springe

Darbyson, Emily A.; Hanson, John Mark; Locke, Andrea; Willison, J. H. Martin (2009) Survival of European green crab (Carcinus maenas L.) exposed to simulated overland and boating-vector transport conditions, Journal of Shellfish Research 28(2): 377-382

Darbyson, Emily; Locke, Andrea; Hanson, John Mark; Willison, J. H. Martin (2009) Marine boating habits and the potential for spread of invasive species in the Gulf of St. Lawrence., Aquatic Invasions 4(1): 87-94

Darling, John A. (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 661-685

Darling, John A. (2011) Interspecific hybridization and mitochondrial introgression in invasive Carcinus shore crabs, PLOS ONE 6(3): e17828

Darling, John A.; Bagley, Mark J.; Roman, Joe; Tepolt, Carolyn K; Geller, Jonathan B.. (2008) Genetic patterns across multiple introductions of the globally invasive crab genus Carcinus., Molecular Ecology 17: 4992-5007

Darling, John A.; Tsai, Yi-Hsin Erica; Blakeslee, April M. H.; Roman, Joe (2014) Are genes faster than crabs? Mitochondrial introgression exceeds larval dispersal during population expansion of the invasive crab Carcinus maenas, Royal Society Open Science 1: 140202

De Kay, James E. (1844) Crustacea, In: (Eds.) Zoology of New-York. , Albany. Pp. <missing location>

de Oliveira Soares, Marcelo Salani, Sula Paiva, Sandra Vieira Andrade Braga, Marcus Davis (2020) Shipwrecks help invasive coral to expand range in the Atlantic Ocean, Marine Pollution Bulletin 158(111394): Published online
https://doi.org/10.1016/j.marpolbul.2020.11139

de Rivera, Catherine E.; Grosholz, Edwin D.; Ruiz, Gregory M. (2011) Multiple and long-term effects of an introduced predatory crab, Marine Ecology Progress Series 429: 145-155

de Rivera, Catherine E.; Hitchcock, Natasha Gray; Teck, Sarah J.; Steves, Brian P. Hines, Anson H. Ruiz, Gregory M. (2007) Larval development rate predicts range expansion of an introduced crab., Marine Biology 150: 1275-1288

de Rivera, Catherine, and 27 authors (2005) Broad-scale non-indigenous species monitoring along the West Coast in National Marine Sanctuaries and National Estuarine Research Reserves report to National Fish and Wildlife Foundation, National Fish and Wildlife Foundation, Washington, D.C.. Pp. <missing location>

de Rivera, Catherine; Ruiz, Gregory M.; Hines, Anson H.; Jivoff, Paul (2005b) Biotic resistance to invasion: Native predator limits abundance and distribution of an introduced crab., Ecology 86(12): 3364-3376

DeGraff, James D.; Tyrrell, Megan C. (2004) Comparison of the feeding rates of two introduced crab species, Carcinus maenas and Hemigrapsus sanguineus, on the blue mussel, Mytilus edulis., Northeastern Naturalist 11(12): 163-167

Delaney, David G.; Edwards, Paul K.; Leung, Brian (2012) Predicting regional spread of non-native species using oceanographic models: validation and identification of gaps, Marine Biology 159: 269-282

DeRoy, Emma M.; Crookes, Steven; Matheson, Kyle; Scott, Ryan; McKenzie, Cynthia H.; Alexander, Mhairi E.; Dick, Jaimie T. A.; MacIsaac, Hugh J. (2022) Predatory ability and abundance forecast the ecological impacts of two aquatic invasive species, Neobiota 71: 91–112

Dexter, Ralph W. (1947) The marine communities of a tidal inlet at Cape Ann, Massachusetts: a study in bio-ecology, Ecological Monographs 17: 261-294

Dexter, Ralph W. (1947) The marine communities of a tidal inlet at Cape Ann, Massachusetts: a study in bio-ecology, Ecological Monographs 17(3): 261-294

Doi, Waturu; Watanabe, Seiichi; Carlton, James T. (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 419-449

Donahue, Megan J. and 6 authors (2009) Predation risk, prey abundance, and the vertical distribution of three brachyuran crabs on Gulf of Maine shores, Journal of Crustacean Biology 29: 523-531

Dow, R. L.; Wallace, D. E. (1952) Observations on green crabs (C. maenas) in Maine., Maine Department of Sea and Shore Fisheries Circular 8: 11-15

Dries, M.; Adelung, D. (1982) Die Schlei, ein modell fur die verbreitung der strandkrabbe Carcinus maenas., Helgoländer Meereseuntersuchungen 35: 65-77

Edgar, G. J.; Barrett, N. S.; Last, P. R. (1999) The distribution of macroinvertebrates and fishes in Tasmanian estuaries., Journal of Biogeography 26(6): 1169-1189

Edgell, Timothy C.; Brazeau, Christian; Grahame, John W.; Rochette, Rémy (2008) Simultaneous defense against shell entry and shell crushing in a snail faced with the predatory shorecrab Carcinus maenas., Marine Ecology Progress Series 371: 191-198

Edgell, Timothy C.; Brazeau, Christian; Grahame, John W.; Rochette, Rémy (2009) Simultaneous defense against shell entry and shell crushing in a snail faced with the predatory shorecrab Carcinus maenas, Marine Ecology Progress Series 371: 191-198

Edgell, Timothy C.; Hollander, John (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 641-655

Edgell, Timothy C.; Rochette, Remy (2008) Differential snail predation by an exotic crab and the geography of shell-claw covariance in the Northwest Atlantic., Evolution 62(5): 1216-1228

Ens, Nicholas J.; Lim, Emily G.: Howard , Brett R.; Eastham, Tao M. (2021) A comparison of the predatory impacts of an invasive and native crab species using a functional response approach, Biological Invasions 23(7): 2329- 2336

Estelle, Veronica; Grosholz, Edwin D. (2012) Experimental test of the effects of a non-native invasive species on a wintering shorebird, Conservation Biology 26(3): 472-481

Fell, Paul E. (1978) Variation in the Time of Annual Degeneration of the Estuarine Sponge, Haliclona loosanoffi, Estuaries 1(4): 281-284

Fisher, Jonathan A. D.; Rhile, Erika C.; Harrison, Liud; Petraitis, Peter S. (2009) An intertidal snail shows a dramatic size increase over the past century, Proceedings of the National Academy of Sciences 106(13): 5209-5212

Fisheries and Oceans Canada 1998 European Green Crab. <missing URL>



Fisheries and Oceans Canada 2011 Aquatic invasive species identification Booklet. <missing URL>



Fisheries and Oceans Canada 2011 Aquatic invasive species: Green Crab in Newfoundland waters. <missing URL>





Floyd, Trevor; Williams, Jim (2004) Impact of green crab (Carcinus maenas L.) predation on a population of soft-shell clams (Mya arenaria L.) in the southern Gulf of St. Lawrence., Journal of Shellfish Research 23(2): 457-462

Flynn, A.M.; Smee, D.L. (2010) Behavioral plasticity of the soft-shell clam, Mya arenaria (L.), in the presence of predators increases survival in the field, Journal of Experimental Marine Biology and Ecology 383: 32-38

Fofonoff, Paul W.; Ruiz, Gregory M.; Hines, Anson H.; Steves, Brian D. Carlton, James T. (2009) Biological Invasions in Marine Ecosystems., Springer-Verlag, Berlin Heidelberg. Pp. 479-505

Food and Agricultural Organization 1998-2012 Database on Introductions of Aquatic Species. <missing URL>



Fowler, Henry (1911) The Crustacea of New Jersey, Annual Report of the New Jersey State Museum, part 2 <missing volume>: 29-610

Freeman, Aaren S.; Wright, Jeffrey T.; Hewitt, Chad L.; Campbell, Marnie L.; Szeto, Kaylene (2013) A gastropod’s induced behavioral and morphological responses to invasive Carcinus maenas in Australia indicate a lack of novelty advantage, Biological Invasions published online: <missing location>

Freeman, Aaren S.; Byers, James E. (2006) Divergent induced responses to an invasive predator in marine mussel populations., Science 313: 831-833

Freeman, Aaren S.; Dernbach, Emily; Marcos, Candice; Koob, Elise (2014) Biogeographic contrast of Nucella lapillus responses to Carcinus maenas, Journal of Experimental Marine Biology and Ecology 452: 1-8

Freeman, Aaren, and 5 authors (2011) Biogeographic comparisons of prey responses to the invasive marine crab Carcinus maenas?, Integrative and Comparative Biology 51: E44

Frizzera, Antonella; Bojko, Jamie;, Cremonte; ´Vazquez, Florencia Nuria (2021) Symbionts of invasive and native crabs, in argentina: the most recently invaded area on the southwestern, Journal of Invertebrate Pathology 184: 107650

Fulton, S.W., Grant, F.E. (1900) Note on the occurrence of the European crab, Carcinus maenas, Leach, in Port Phillip, Victorian Naturalist 17(8): 147

Furlani, Dianne M. (1996) A guide to the introduced marine species in Australian waters., In: (Eds.) . , Hobart, Australia. Pp. <missing location>

Garbary, David J.; Miller, Anthony G.; Williams, Jim; Seymour, Norm R. (2014) Drastic decline of an extensive eelgrass bed in Nova Scotia due to the activity of the invasive green crab (Carcinus maenas), Marine Biology 161: 3-15

Garside, C. J.; Bishop, M. J. (2014) The distribution of the European shore crab, Carcinus maenas, with respect to mangrove forests in southeastern Australia, Journal of Experimental Marine Biology and Ecology 461: 173-178

Garside, C. J.; Glasby, T. M.; Coleman, M. A.; Kelaher, B. P.; Bishop, M. J. (2014) The frequency of connection of coastal water bodies to the ocean predicts Carcinus maenas invasion, Limnology and Oceanography 59(4): 1288-1296

Garside, C. J.; Glasby, T. M.; Stone, L. J.; Bishop, M. J. (2016) The timing of Carcinus maenas recruitment to a south-east Australian estuary differs to that of native crabs, Hydrobiologia 762: 41-53

Geller, J. B.; Walton, E. D.; Grosholz, E. D.; Ruiz, G. M. (1997) Cryptic invasions of the crab Carcinus detected by molecular phylogeography, Molecular Ecology 6: 901-906

Glude, John B. (1955) The effects of temperature and predators on the abundance of the soft-shell clam, Mya arenaria, in New England., Transactions of the American Fisheries Society 84: 13-26.

Goddard, Jeffrey H.; Torchin, Mark E.; Kuris, Armand M.; Lafferty, Kevin D. (2005) Host specificity of Sacculina carcini, a potential biological control agent of the introduced European green crab Carcinus maenas in California., Biological Invasions 7: 895-912

Gould, Augustus A. (1841) <missing title>, Folsom, Wells, and Thurston, Cambridge. Pp. <missing location>

Grabowski, Michal; Jazdewski, Kryzystof; Konopacka, Alicia, (2005) Alien Crustacea In Polish waters - Introduction and Decapoda., Oceanological and Hydrobiological Studies 34(2): 43-61

Green, Stephanie J.; Grosholz, Edwin D. (2021) Functional eradication as a framework for invasive species control, Frontiers in Ecology and the Environment 19(2): 98-107

Griffen, Blaine D. (2006) Detecting emergent effects of multiple predator species., Oecologia 148: 702-709

Griffen, Blaine D. (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 687-699

Griffen, Blaine D.; Altman, Irit; Hurley, Joan; Mosblack, Hallie (2011) Reduced fecundity by one invader in the presence of another: A potential mechanism leading to species replacement, Journal of Experimental Marine Biology and Ecology 406: 6-13

Griffen, Blaine D.; Byers, James E. (2006) Intraguild predation reduces redundancy of predator species in multiple predator assemblage., Journal of Animal Ecology 75: 959-966

Griffen, Blaine D.; Byers, James E. (2006) Partitioning mechanisms of predator interference in different habitats., Oecologia 146: 608-614

Griffen, Blaine D.; Byers, James E. (2009) Community impacts of two invasive crabs: the interactive roles of density, prey recruitment, and indirect effects., Biological Invasions 11: 927-940

Griffen, Blaine D.; Delaney, David G. (2007) Species invasion shifts the importance of predator dependence., Ecology 88(12): 3012-3021

Griffen, Blaine D.; Guy, Travis; Buck, Julia C. (2008) Inhibition between invasives: a newly introduced predator moderates the impacts of a previously established invasive predator., Journal of Animal Ecology 77(1): 32-40

Griffen, Blaine D.; Riley, Megan E. (2015) Potential impacts of invasive crabs on one life history of invasive rock crabs in the Gulf of Maine, Biological Invasions 17(9): 2533-2544

Griffen; Blaine D.; Williamson, Blaine D. (2008) Influence of predator density on nonindependent effects of multiple predator species., Oecologia 155: 151-159

Griffiths, C. L., Hockey, P. A. R., van Erkom Schurink, C., le Roux, P. J. (1992) Marine invasive aliens on South African shores: implications for community structure and trophic functioning, South African Journal of Marine Science 12: 713-722

Griffiths, Charles, Robinson, Tamara; Mead, Angela (2011) In the wrong place- Alien marine crustaceans: Distribution, biology, impacts, Springer, Dordrecht, Netherlands. Pp. 269-282

Grosholz, E.D.; Ruiz, G.M. (1995) Spread and potential impact of the recently introduced European green crab, Carcinus maenas, in central California, Marine Biology 122: 239-247

Grosholz, Edwin (2002) Ecological and evolutionary consequences of coastal invasions., Trends in Ecology and Evolution 17(1): 22-27

Grosholz, Edwin (2011) Encyclopedia of Biological Invasions, University of California Press, Berkeley and Los Angeles. Pp. 125-128

Grosholz, Edwin D. (1996) Contrasting rates of spread for introduced species in terrestrial and marine systems, Ecology 77(6): 1680-1686

Grosholz, Edwin D. (2005) Recent biological invasion may hasten invasion meltdown by accelerating historical introductions., Proceedings of the National Academy of Sciences of the U.S.A. 102(4): 1088-1091

Grosholz, Edwin D.; Ruiz, Gregory M. (2009) Biological Invasions in Marine Ecosystems., Springer-Verlag, Berlin Heidelberg. Pp. 305-323

Grosholz, Edwin D.; Ruiz, Gregory M.; Dean, Cheryl A.; Shirley, Kim A.; Maron, John L.; Connors, Peter G. (2000) The impacts of a nonindigenous marine predator in a California bay., Ecology 81(5): 1206-1224

Grosholz, Edwin; Lovell, Sabrina; Besedin, Elena ; Katz, Marilyn (2011) Modeling the impacts of the European green crab on commercial shellfisheries, Ecological Applications 21(3): 915-924

Grosholz, Edwin; Olin, Paul; Williams, Briar; Tinsman, Rico (2001) Reducing predation on manila clams by nonindigenous European green crabs., Journal of Shellfish Research 20(3): 913-919

Grosholz, Edwin; Ruiz, Gregory (2002) Management plan for the European green crab., In: None(Eds.) None. , <missing place>. Pp. 1-55

Grosholz, Edwin; Ruiz, Gregory M. (1996) Predicting the impacts of introduced marine species: Lessons from the multiple invasions of the European green crab., Biological Conservation <missing volume>: 59-66

Grosholza, Edwin; Ashton, Gail; Bradley, Marko; Brownb, Chris; Ceballos-Osun, Lina; Chang, Andrew; de Rivera, Catherine; Gonzaleza, Julie; Heinekea, (2021) Stage-specific overcompensation, the hydra effect, and the failure to eradicate an invasive predator, Proceedings of the National Academy of Sciences of the U.S.A. 118(12): e2003955118

Haarr, Marthe Larsen; Rochette, Rémy (2012) The effect of geographic origin on interactions between adult invasive green crabs Carcinus maenas and juvenile American lobsters Homarus americanus in Atlantic Canada, Journal of Experimental Marine Biology and Ecology 422-423: 88-100

Hadlock, Robin P. (1980) Alarm response of the intertidal snail Littorina littorea (L.) to predation by the crab Carcinus maenas (L.), Biological Bulletin 159: 269-279

Hardwick-Witman, Morgan; Mathieson, Arthur C. (1983) Intertidal macroalgae and macroinvertebrates: seasonal and spatial abundance patterns along an estuarine gradient., Estuarine Coastal and Shelf Science 16: 113-129

Harris, Larry G.; Jones, Adam C. (2005) Temperature, herbivory and epibiont acquisition as factors controlling the distribution and ecological role of an invasive seaweed., Biological Invasions 7: 913-924.

Harvard Museum of Comparative Zoology 2008-2021 Museum of Comparative Zoology Collections database- Malacology Collection. <missing URL>



Haupt, T. M.; Griffiths, C. L.; Robinson, T. B.;Tonin, A. F. G. (2010) Oysters as vectors of marine aliens, with notes on four introduced species associated with oyster farming in South Africa, African Zoology 45: 52-62

Heger, Tina; Trepl, Ludwig (2003) Predicting biological invasions., Biological Invasions 5: 313-321

Hewitt, C.L.; Campbell, M.L.; Thresher, R.E.; Martin, R.B. (1999) Marine Biological Invasions of Port Phillip Bay, Victoria, In: (Eds.) . , Hobart, Tasmania. Pp. <missing location>

Hidalgo, Fernando J.; Baron, Pedro J.; Orensanz, Maria (2005) A prediction come true: the green crab invades the Patagonian coast., Biological Invasions 7: 547-552

Hines, Anson H.; Ruiz, Gregory M.; Hitchcock, Natasha Gray; de Rivera, Catherine (2004) <missing title>, <missing publisher>, <missing place>. Pp. <missing location>

Hoagland, Porter; Jin, Di (2006) Science and economics in the management of an invasive species., BioScience 56(11): 931-935

Howard, Brett R.; Wong, Dickson T. S.; Aguiar, Veronica, Desforges, Jessica; Oishi, Elizabeth M.; Stewart, Jordan; Côté, Isabelle M. (2022) Effects of perceived competition and water temperature on the functional responses of invasive and native crabs, Marine Ecological Progress Series 684: 69-79
https://doi.org/10.3354/meps13974

Hudson, D. M.; Sexton, D. J.; Wint, D.; Crivello, J. F. (2011) Invasive crab salinity preference: effects of acclimation and implications for estuarine distribution, Integrative and Comparative Zoology 51(1): 203

Hutchings, P., van der Velde, J., Keable, S. (1986) Colonisation of NSW by foreign marine species, Australian Fisheries 45(4): 40-42

Hutchings, P., van der Velde, J., Keable, S. (1988) Baseline survey of the benthic macrofauna of Twofold Bay, New South Wales (Australia) with a discussion of the marine species introduced into the Bay, Proceedings of the Linnean Society of New South Wales 110(3-4): 339-368

ICES Advisory Committee on the Marine Environment (2004) <missing title>, International Council for the Exploration of the Seas, Copenhagen. Pp. <missing location>

ICES Advisory Committee on the Marine Environment (2012) <missing title>, International Council for the Exploration of the Seas, Copenhagen. Pp. <missing location>

Jamieson, G. S., Grosholz, E. D., Armstrong, D. A., Elner, R. W. (1998) Potential ecological implications from the introduction of the European Green Crab, Carcinus maenas (Linnaeus) to British Columbia, Canada, and Washington, USA., Journal of Natural History 32: 1587-1598

Jamieson, Glen S. (2002) Alien invaders: In Canada's waters, wetlands, and forests, Natural Resources Canada, Ottawa, Ontario. Pp. 179-186

Jazdzewski, Krzysztof; Konopacka, Alicja; Grabowski, Michal; (2005) Native and alien malacostracan Crustacea along the Polish Baltic Sea coast In the twentieth century., Oceanological and Hydrobiological Studies 34(Suppl. 1.): 175-193

Jenkins, Stuart R. and 9 authors (2008) Comparative ecology of North Atlantic shores: do differences in players matter for process?, Ecology 89(11): S3-S23

Jensen, G.C.; McDonald, P. S.; Armstrong, D. A. (2002) East meets west: competitive interactions between green crab Carcinus maenas, and native and introduced shore crab Hemigrapsus spp., Marine Ecology Progress Series 225: 151-262

Jensen, Gregory C.; McDonald, P. Sean; Armstrong, David A. (2007) Biotic resistance to green crab, Carcinus maenas, in California bays., Marine Biology 151: 2231-2243

Johnson, William S.; Allen, Dennis M. (2005) <missing title>, Johns Hopkins Press, Baltimore. Pp. <missing location>

Joska, M. A. P., Branch, G. M. (1986) The European shore-crab - another alien invader?, African Wildlife 40(2): 63-65

Kanary, Lisa; Musgrave, Jeffrey; Tyson, Rebecca C.; Locke, Andrea; Lutscher, Frithjof (2014) Modelling the dynamics of invasion and control of competing green crab genotypes, Theoretical Ecology 7: 391-406

Keller, Abigail G.; Grason, Emily W.; McDonald, P. Sean; Ramón-Laca, Ana; Kelly, Ryan P. (2021) Tracking an invasion front with environmental DNA, Ecological Applications <missing volume>: https://esajournals.

Kelley, Amanda L.; de Rivera, Catherine E.; Buckley, Bradley A. (2011) Intraspecific variation in thermotolerance and morphology of the invasive European green crab, Carcinus maenas, on the west coast of North America, Journal of Experimental Marine Biology and Ecology 409: 70-78

Kilian, Jay V. and 6 authors (2012) An assessment of a bait industry and angler behavior as a vector of invasive species, Biological Invasions 14: published online

Kilian, Jay V. and 6 authors (2010) The status and distribution of Maryland crayfishes, Southeastern Naturalist 9(Special Issue 3): 11-32

Kim, Daemin; Taylor, Andrew T.; Near, Thomas J. (2022) Phylogenomics and species delimitation of the economically important Black Basses (Micropterus), Scientific Reports 12(9113): Published online
https://doi.org/10.1038/s41598-022-11743-2

Kimbro, David L. and 6 authors (2009) Invasive species cause large-scale loss of native California oyster habitat by disrupting trophic cascades., Oecologia 160: 563-575

Kingsley, J.S. (1879) On a collection of Crustacea from Virginia, North Carolina, and Florida, with a revision of the genera of Crangonidae and Palaemonidae., Proceedings of the Academy of Natural Sciences of Philadelphia 31: 383-427

Klassen, Greg; Locke, Andrea (2007) A biological synopsis of the European Green Crab, Carcinus maenas, Canadian Manuscript Report of Fisheries and Aquatic Sciences 2818: 1-75

Kuris, Armand M. (2000) Can biological control be developed as a safe and effective mitigation against established introduced marine pests?, In: (Eds.) Marine Bioinvasions. , <missing place>. Pp. <missing location>

Kuris, Armand; Sadeghian, Patricia S.; Carlton, James T. (2007) The Light and Smith Manual: Intertidal Invertebrates from Central California to Oregon, University of California Press, Berkeley CA. Pp. 636-656

Lages, B. G. Fleury, B. G. Menegola, C. Creed, J. C. (2011) Change in tropical rocky shore communities due to an alien coral invasion, Marine Ecology Progress Series 438: 85-96

Lange, Rolanda; Marshall, Dustin J. (2016) Relative contributions of offspring quality and environmental quality to adult field performance, Oikos 125: 210-217

Large, Scott I.; Smee, Delbert L. (2013) Biogeographic variation in behavioral and morphological responses to predation risk, Oecologia 171: 961-969

Larsen, Peter Foster (2012) The macroinvertebrate fauna of rockweed (Ascophyllum nodosum) dominated low-energy rocky shores of the northern Gulf of Maine, Journal of Coastal Research 28(1): 36-42

Le Roux, P.J., G.M. Bauch, M.A.P. Joska. (1990) On the distribution, diet and possible impact of the invasive European shore crab Carcinus maenas (L.) along the South African coast., South African Journal of Marine Science 9: 85-93

League-Pike, Paloma E.; Shulman, Myra, J. (2009) Intraguild predators: behavioral changes and mortality of the green crab (Carcinus maenas) during interactions with the American lobster (Homarus americanus) and jonah crab (Cancer borealis), Journal of Crustacean Biology 29(3): 350-355

Leathem, Wayne; Maurer, Don (1980) Decapod crustaceans of the Delaware Bay area, Journal of Natural History 14(6): 813-828

Leidy, Joseph (1855) Contributions towards a knowledge of the marine invertebrate fauna, of the coasts of Rhode Island and New Jersey, Journal of the Academy of Natural Sciences of Philadelphia <missing volume>: 135-151

Leignel, V.; Stillman, J. H.; Baringou, S.; Thabet, R.; Metais, I. (2014) Overview on the European green crab Carcinus spp. (Portunidae, Decapoda), one of the most famous marine invaders and ecotoxicological models, Environmental Science and Pollution Research International 21(15): 9129-9144

Lins, Daniel M.; de Marco, Paulo Jr.; Andrade, Andre F. A.; Rocha, Rosana M. (2023) Predicting global ascidian invasions, Diversity and Distributions 24: 692–704
https://onlinelibrary.wiley.com/doi/full/10.1111/ddi.12711

Lohrer, Andrew M., Whitlatch, Robert B. (1997) Ecological studies on the recently introduced Japanese shore crab (Hemigrapsus sanguineus), in eastern Long Island Sound., In: Balcom, Nancy C.(Eds.) Proceedings of the Second Northeast Conference on Nonindigenous Aquatic Nuisance Species.. , Groton. Pp. 49-60

Lohrer, Andrew M.; Whitlatch, Robert (2002a) Relative impacts of two exotic brachyuran species on blue mussel populations in Long Island Sound., Marine Ecology Progress Series 227: 135-144.

Lohrer, Andrew; Whitlatch, Robert B. (2002b) Interactions among aliens: apparent replacement of one exotic species by another., Ecology 83(3): 719-732

Loveland, Robert E.; Vouglitois, James J. (1984) Benthic fauna., In: Kennish, Michael J./, and Lutz, Richard A.(Eds.) Ecology of Barnegat Bay, New Jersey.. , Berlin. Pp. 135-170

Luiz, Osmar J. and 7 authors (2021) Multiple lionfish (Pterois spp.) new occurrences along the Brazilian coast confirm the invasion pathway into the Southwestern Atlantic, Biological Invasions Published online: <missing location>

Lutz-Collins, Vanessa; Quijon, Pedro A. (2014) Animal-sediment relationships in an Atlantic Canada marine protected area: Richness, composition and abundance in relation to sediment food indicators, Marine Biology Research 10(6): 577-588

Lynch, Brian R.; Rochette, Rémy (2009) Spatial overlap and interaction between sub-adult American lobsters, Homarus americanus, and the invasive European green crab Carcinus maenas, Journal of Experimental Marine Biology and Ecology 369: 127-135

Mabin, Clova A. Robinson, Tamara B. Wilson, John R. U. · Heidi Hirsch · Castillo, Maria L. · Jooste, Michelle Le Roux, Johannes J. (2022) Molecular insights into the invasion dynamics of Carcinus crabs in South Africa, None <missing volume>: Published online
https://doi.org/10.1007/s10530-022-02865-9

MacDonald, James A.; Roudez, Ross; Glover, Terry; Weis, Judith S. (2007) The invasive green crab and Japanese shore crab: behavioral interactions with a native crab species, the blue crab., Biological Invasions 9: 837-848

Malpass, Wendy, Geist, Margaret A. (1996) Chapter III: Habitats and communities of the Waquoit Bay reserve., In: Geist, Margaret A.(Eds.) Waquoit Bay National Estuarine Research Reserve. , Massachusetts. Pp. <missing location>

Marculis, Nathan G.; Lui, Roger (2015) Modelling the biological invasion of Carcinus maenas (the European green crab), Journal of Biological Dynamics 10(1): 140-163

Marquez, Federico M.; Zabala, Soledad; Bokenhans, Verena; Cumplido, Mariano; Espinosa, Free; Bigatti, Gregorio; Averbuj, Andres (2024) Predation of the invasive green crab Carcinus maenas on the edible snail Buccinastrum deforme, targeted as the most important nearshore marine gastropod fishery from Patagonia, Argentina, Regional Studies in Marine Science 69(103299): Published online
https://doi.org/10.1016/j.rsma.2023.103299

Massachusetts Office of Coastal Zone Management (2013) Rapid assessment survey of marine species at New England floating docks and rocky shores, Massachusetts Office of Coastal Zone Management, Boston MA. Pp. <missing location>

Matheson, Kyle; Gagnon, Patrick (2012) Temperature mediates non-competitive foraging in indigenous rock (Cancer irroratus Say) and recently introduced green (Carcinus maenas L.) crabs from Newfoundland and Labrador, Journal of Experimental Marine Biology and Ecology 414-415: 6-18

Matheson, Kyle; Gagnon, Patrick (2012) Effects of temperature, body size, and chela loss on competition for a limited food resource between indigenous rock crab (Cancer irroratus Say) and recently introduced green crab (Carcinus maenas L.), Journal of Experimental Marine Biology and Ecology 428: 49-56

Mathieson, Arthur C.; Dawes, Clinton J. (2017) Seaweeds of the Northwest Atlantic, University of Massachusetts Press, Amherst MA. Pp. <missing location>

McDonald, P. Sean; Holsman, Kirsten K., Beauchamp, David A.; Dumbauld, Brett R., and Armstrong, David A (2006) Bioenergetics modeling to investigate habitat use by the nonindigenous crab, Carcinus maenas, in Willapa Bay, Washington., Estuaries and Coasts 29(6B): 1132-1149

McDonald, P. Sean; Jensen, Gregory C.; Armstrong, David A. (2001) The competitive and predatory impacts of the nonindigenous crab Carcinus maenas (L.) on early benthic phase Dungeness crab Cancer magister Dana., Journal of Experimental Marine Biology and Ecology 258: 39-54

McGaw, Iain J.; Edgell, Timothy C.; Kaiser, Michel J. (2011) Population demographics of native and newly invasive populations of the green crab Carcinus maenas, Marine Ecology Progress Series 430: 235-240

McKenzie, Cynthia H.; Matheson, Kyle; Sargent, Philip S.; Piersiak, Michael; Bernier. Renee Y.; Simard, Nathalie; Therriault, Thomas W. (2022) Trapping methods for the Invasive European Green Crab in Canada, DFO Can. Sci. Advis. Sec. Res. Doc <missing volume>: 1-53

McKnight, Aly, (2000) Distribution is correlated with color phase in green crabs in southern New England, Crustaceana 73(6): 763-768

McNaught, Douglas C.; Norden, Wendy S. (2011) Generalized regional spatial patterns of larval recruitment of invasive ascidians, mussels, and other organisms along the coast of Maine, Aquatic Invasions 6(4): 519-523

McVean, Alistair M. (1976) The incidence of autotomy in Carcnius maenas, Journal of Experimental Marine Biology and Ecology 24: 177-187

Mead, A.; Carlton, J. T.; Griffiths, C. L. Rius, M. (2011b) Introduced and cryptogenic marine and estuarine species of South Africa, Journal of Natural History 39-40: 2463-2524

Miller, Douglas; Brown, Jill. (2005) Maryland’s Coastal Bays: Ecosystem Health Assessment., Maryland Department of Natural Resources., Annapolis. Pp. 8/100-8/105

Miller, Raegan KRBD - Ketchikan 7/29/2022 For the first time, live invasive green crabs have been found in Alaska. https://www.ktoo.org/2022/07/28/live-invasive-european-green-crabs-found-in-alaska/#:~:text=When%20M



Miller, Todd W. (1996) First record of the green crab Carcinus maenas, in Humboldt Bay, California., California Fish and Game 82(2): 93-96

Milne, H.; Dunnet, G. M. (1972) The Estuarine Environment., Applied Science Publishers, London. Pp. 86-106

Miron, Gilles; Audet, Dominique; Landry, Thomas; Moriyasu, Mikio (2005) Predation potential of the invasive green crab
Carcinus maenas
and other common predators on commercial bivalve species found on Prince Edward Island., Journal of Shellfish Research 24(2): 579-586

MIT Sea Grant 2003-2008 Introduced and cryptogenic species of the North Atlantic. <missing URL>



MIT Sea Grant 2009-2012 Marine Invader Tracking and Information System (MITIS). <missing URL>



Monod, T. H. (1956) Hippidea et Brachyruea ouest-africains, Memoires de lInstitut Francais dAfrique Noire 45: 1-674

Morton, B.; Britton, J.C. (2000) Origins of the Azorean intertidal biota: the significance of introduced species, survivors of chance events., Arquipelago. Life and Marine Sciences supplement 2 (part A): 29-51

Murphy, N. E.; Goggin, C. L. (2000) Genetic discrimination of sacculinid parasites (Cirripedia, Rhizocephala): implication for control of introduced green crabs (Carcinus maenas), Journal of Crustacean Biology 20(1): 153-157

Museum of Comparative Zoology 2008-2015 Invertebrate Zoology Collections Database http://mczbase.mcz.harvard.edu/SpecimenSearch.cfm. <missing URL>



Newsom, Amanda J.; Williams, Susan L. (2014) Predation and functional responses of Carcinus maenas and Cancer magister in the presence of the introduced cephalaspidean nPhiline orientalis, Estuaries and Coasts 37: 1284-1294

Nizinski, Martha S. (2003) Annotated checklist of decapod crustaceans of Atlantic coastal and continental shelf waters of the United States., Proceedings of the Biological Society of Washington 116(1): 96-157

O’Connor, Nancy J. (2013) Invasion dynamics on a temperate rocky shore: from early invasion to establishment of a marine invader, Biological Invasions published online: <missing location>

Orlova-Bienkowskaja, Marina J. Volkovitsh, Mark G. (2018) Are native ranges of the most destructive invasive pests well known? A case study of the native range of the emerald ash borer, Agrilus planipennis (Coleoptera: Buprestidae), Biological Invasions 20: 1275–1286

Palacios, Kelly C.; Ferraro, Stephen P. (2003) Green crab consumption rates on and prey preferences among four bivalve prey species, Journal of Shellfish Research 22(3): 265-271

Pascoal, Sonia; Creer, Simon; Taylor, Martin I.; Queiroga, Henrique; Carvalho, Gary; Mendo, Sonia (2009) Development and application of microsatellites in Carcinus maenas: genetic differentiation between northern and central Portuguese populations, PLOS ONE 4(9): e7268

Pearce, John B. (1974) Invertebrates of the Hudson River estuary, Annals of the New York Academy of Sciences 250: 137-173

Peck, Stewart B.; Heraty, John; Landry, Bernard; Sinclair, Bradley J. (1998) Introduced insect fauna of an oceanic archipelago: The Galapagos Islands, Ecuador, American Entomologist 44: 218-237

Pederson, Judith, and 13 authors (2021) 2019 Rapid Assessment Survey of marine bioinvasions of southern New England and New York, USA, with an overview of new records and range expansions, Bioinvasions Records 10(2): 22-–237

Percy, J. A. 2003 Alien Invasions: introduced species to the Bay of Fundy and environs. <missing URL>



Perez, Bianca J.;Segrest, Averi Harp; Campos, Sofia R.; Minton, Russell L.; Burks, Romi L. (2016) First record of Japanese Mystery Snail Cipangopaludina japonica (von Martens, 1861) in Texas, Check List 12(1973): Published online
http://dx.doi.org/10.15560/12.5.1973

Perkins, E. J., Gribbon, E., Murray R. B. (1969) Some aspects of biology of Carcinus maenas (L) II. Survival at low salinity, Transactions of the Dumfrieshire and Galloway Natural History Antiquarian Society 46: 27-28

Peterson, Charles H. (1979) The importance of predation and competition in organizing the intertidal epifaunal communities of Barbegat inlet, New Jersey, Oecologia 39: 1-24

Pickering, Timothy D.;Skelton, Posa; Sulu, Reuben J. (2007) Intentional introductions of commercially harvested alien seaweeds., Botanica Marina 50: 338-350

Pickering, Tyler; Quijon, Pedro (2011) Potential effects of a non-indigenous predator in its expanded range: assessing green crab, Carcinus maenas, prey preference in a productive coastal area of Atlantic Canada, Marine Biology 158: 2065-2078

Pilsbry, H.; Vanatta, E. G. (1902) Papers from the Hopkins Stnaford Galapagos Expedtion, 1898-1899, prceedings of the Washington Academy of Science 4: 549-560

Pohle, David G., Bricelj, V. Monica, García-Esquivel, Zaúl (1991) The eelgrass canopy: an above-bottom refuge from benthic predators for juvenile bay scallops Argopecten irradians, Marine Ecology Progress Series 74: 47-59

Popp, Teresa; Dwilber, ara H. (2021) Associations between winter temperatures and the timing and duration of annual larval recruitment of a non-native anomuran crab, Biological Invasions 44: 1074-1082

Poulsen, Erik M. (1922) On the frequency and distribution of Crangon vulgaris, Carcinus maenas and Portunus holstatus in the Danish coastal waters., Meddelelser Fra Kommissionen for Havundersøgelser, Serie: Fiskeri. 6(7): 1-18

Pringle, James M.; Blakeslee, April M. H.; Byers, James E.; Roman, Joe (2011) Asymmetric dispersal allows an upstream region to control population structure throughout a species’ range, Proceedings of the National Academy of Sciences 108: 15288-15293

Queiroga, Henrique, Costlow, John D., Moreira, Maria Helena (1994) Larval abundance patterns of Carcinus maenas (Decapoda: Brachyura) in Canal de Mira (Ria de Aveiro, Portugal), Marine Ecology Progress Series 111: 63-72

Quinn, Brady K.; Boudreau, Melanie R.; Hamilton, Diana J. (2012) Inter- and intraspecific interactions among green crabs (Carcinus maenas) and whelks (Nucella lapillus) foraging on blue mussels (Mytilus edulis), Journal of Experimental Marine Biology and Ecology 412: 117-125

Radashevsky,Vasily I.; Pankova, Victoria V.; Malyar, Jose Cerca;; StruckTorsten H. (2021) A review of the worldwide distribution of Marenzelleria viridis, with new records for M. viridis, M. neglecta and Marenzelleria sp. (Annelida: Spionidae), Zootaxa 5081(3): 353-372

Rafinesque, Constantine S. (1817) Synopsis of four new genera and ten new species of Crustacea, found in the United States., American Monthly Magazine 2: 40-43

Rangeley, R.W., Thomas, M.L.H. (1987) Predatory behaviour of juvenile shore crab Carcinus maenas (L.), Journal of Experimental Marine Biology and Ecology 108: 191-197

Rathbun, Mary J. (1930) The cancroid crabs of America of the families Euryalidae, Portunidae, Atelecyclidae, Cancridae, and Xanthidae, United States National Museum Bulletin 152: 1-609

Rice, Ammon; Tsukimura, Brian (2007) A key to the identification of brachyuran zoeae of the San Francisco Bay estuary., Journal of Crustacean Biology 27: 74-79

Ro, Hyejoo; Fowler, Amy E.; Wood, Chelsea L.; Blakeslee, April M. H. (2022) Trematode parasites have minimal effect on the behavior of invasive green crabs, Aquatic Invasions 17(2): 238–258

Robertson, Robert (1980) Phillippia (Psilaxsis) radiata: Another Indo-Pacific Architectonia newly found in the Indo-Pacific (Colombia), Veliger 22(2): 22

Robinson, April; Cohen, Andrew N.; Lindsey, Brie; Grenier, Letitia (2011) Distribution of macroinvertebrates across a tidal gradient, Marin County, California, San Francisco Estuary and Watershed Science 9(3): published online

Robinson, C. B. (1904) The distribution of Fucus serratus in North America, Torreya 3: 132-134

Robinson, T. B.; Griffiths, C. L.; Kruger, N. (2004) Distribution and status of marine invasive species in and bordering the West Coast National Park., Koedoe 47: 79-87

Robinson, T. B.; Griffiths, C. L.; McQuaid, C. D.; Rius, M. (2005) Marine alien species of South Africa-- status and impacts, African Journal of Marine Science 27(1): 297-306

Roft, John C.; Davidson, Kevin G.; Pohle, Gerhard; Dadswell, Michael J. (1984) A guide to the marine flora and fauna of the Bay of Fundy and Scotian shelf: larval Decapoda: Brachyura, Canadian Technical Report of Fisheries and Aquatic Sciences 1322: 1-57

Roman, Joe; Palumbi, Stephen R. (2004) A global invader at home: population structure of the green crab, Carcinus maenas, in Europe., Molecular Ecology 13: 2891-2898

Roman, Joe. (2006) Diluting the founder effect: cryptic invasions expand a marine invader's range., Marine Ecology Progress Series 311: 251-262

Ropes, John W. (1989) The food habits of five crab species at Pettaquamscutt River, Rhode Island, Fishery Bulletin 87(1): 197-204

Ross, D. J.; Johnson, C. R.; Hewitt, C. L.; Ruiz, G. M. (2004) Interaction and impacts of two introduced species on a soft-sediment marine assemblage in SE Tasmania., Marine Biology 144: 747-756

Rossong M. A.; Williams, P. J.; Comeau, M.; Mitchell, S.C.; Apaloo, J. (2006) Agonistic interactions between the invasive green crab, Carcinus maenas (Linnaeus) and juvenile American lobster, Homarus americanus (Milne Edwards)., Journal of Experimental Marine Biology and Ecology 329: 281-288

Rossong, M. A.; Quijon, P. A.; Williams, P. J.; Snelgrove, P. V. R. (2011) Foraging and shelter behavior of juvenile American lobster (Homarus americanus): the influence of a non-indigenous crab, Journal of Experimental Marine Biology and Ecology 403: 75-80

Rossong, Melanie A. and 5 authors (2011) Regional differences in foraging behaviour of invasive green crab (Carcinus maenas) populations in Atlantic Canada, Biological Invasions 13: published online

Roudez, Ross J.; Glover, Terry; Weis, Judith S. (2008) Learning in an invasive and a native predatory crab., Biological Invasions 10: 1191-1196

Ruiz, Gregory M., Miller, Whitman, Walton, William C. (1998) Bi-coastal invasion of North America by the European green crab: Impacts and management strategies, In: (Eds.) . , Washington, D.C.. Pp. <missing location>

Ruiz, Gregory M.; Geller, Jonathan (2018) Spatial and temporal analysis of marine invasions in California, Part II: Humboldt Bay, Marina del Re, Port Hueneme, and San Francisco Bay, Smithsonian Environmental Research Center & Moss Landing Laboratories, Edgewater MD, Moss Landing CA. Pp. <missing location>

Sanchez-Telumbre,, N. A.; Torreblanca-Ramírez, C.1 ; Padilla Serrato, J. G.1,2 , Flores Rodríguez, P.; , Flores-Garza, R.; , Kuk-Dzul. J. G (2021) Mollusks associated to the rock oyster Striostrea prismatica Gray, 1825 in Corrales Beach, Jalisco, Mexico, Revista Bio Ciencias 9: e1072.

Savoya, Verónica; Schwindt, Evangelina (2010) Effect of the substratum in the recruitment and survival of the introduced barnacle Balanus glandula (Darwin 1854) in Patagonia, Argentina, Journal of Experimental Marine Biology and Ecology 382: 125-130

Say, Thomas (1817) An account of the Crustacea of the United States., Journal of the Academy of Natural Sciences of Philadelphia 1(1,2): 57-63, 65-80, 97-101

Scattergood, Leslie W. (1952) The distribution of the green crab (Carcinides maenas) in the Northwest Atlantic, Maine Department of Sea and Shore Fisheries Circular <missing volume>(8): 1-7

Schaefer, Gesa; Zimmer, Martin (2013) Ability of invasive green crabs to handle prey in a recently colonized region, Marine Ecology Progress Series 483: 221-229

Scuchert, Peter (2010) The European athecate hydroids and their medusae (Hydrozoa, Cnidaria): Capitata Part 2, Revue Suisse de Zoologie 117(3): 337-355

Seattle Times Staff 5/12/2022 Invasive European green crab found in Hood Canal for first time. https://www.seattletimes.com/seattle-news/environment/invasive-european-green-crab-found-in-hood-can



Secord, David (2003) Biological control of marine invasive species: cautionary tales and land-based lessons., Biological Invasions 5: 117-131

See, Kevin E.; Feist, Blake E. (2010) Reconstructing the range expansion and subsequent invasion of introduced European green crab along the west coast of the United States, Biological Invasions 12: 1305-1318

Seeley, Robin Hadlock (1986) Intense natural selection caused a rapid morphological transition in a living marine snail., Proceedings of the National Academy of Sciences of the U.S.A. 83: 6897-6901

Sigwart, Julia D.;; Wong, Nur Leena W. S.; Esa, Yuzine (20201) Global controversy in oyster systematics and a newly described species from SE Asia (Bivalvia: Ostreidae: Crassostreinae), Marine Biodiverisity 51(83): Published online

Simard, Par Nathalie; McKindsey, Chris; Archambault, Philippe; Cyr, Charley (2005) Decouverte d'especes marine envahissantes aux iles de la Madeleine., Naturaliste Canadienne 129(2): 62-64

Smith, L. David (2004) Biogeographic differences in claw size and performance in an introduced crab predator Carcinus maenas, Marine Ecology Progress Series 276: 209-222

Smith, L. David (2009) Biological Invasions in Marine Ecosystems., Springer-Verlag, Berlin Heidelberg. Pp. 177-202

Spaargaren, D. H. (1989) Adaptation to estuarine conditions in shore crabs Carcinus maenas (L.) in relation to body size, Journal of Experimental Marine Biology and Ecology 129: 251-263

St-Hilaire, Sophie; Krause, Juergen; Wight, Karen; Poirier, Luke; Singh, Kehar (2016) Break-even analysis for a green crab fishery in PEI, Canada, Management of Biological Invasions 7: In press

Strauss, Sharon Y.; Lau, Jennifer A.; Carroll, Scott P. (2006) Evolutionary responses of natives to introduced species: what do introductions tell us about natural communities?, Ecology Letters 9: 357-374

Streit, Olivia T; Lambert, Gretchen; Erwin, Patrick M.; Lopez-Legentil, Susanna (2021) Diversity and abundance of native and non-native ascidians in Puerto Rican harbors and marinas, Marine Pollution Bulletin 167(112262): Published online

Sumner, Francis B., Osburn, Raymond C., Davis, Bradley M. (1913a) A biological survey of the waters of Woods Hole and vicinity. Part I. Section I. Physical and Zoological. Section II. Botanical, Bulletin of the Bureau of Fisheries 31: 1-544

Sumner, Francis B.; Osburn, Raymond C.; Cole, Leon J.; Davis, Bradley M. (1913b) A biological survey of the waters of Woods Hole and vicinity Part II. Section III. A catalogue of the marine fauna Part II. Section IV. A catalogue of the marine flora, Bulletin of the Bureau of Fisheries 31: 539-860

Tan, Eric Bryan P.; Beal, Brian F. (2015) Interactions between the invasive European green crab, Carcinus maenas (L.), and juveniles of the soft-shell clam, Mya arenaria L., in eastern Maine, USA, Journal of Experimental Marine Biology and Ecology 462: 62-73

Tanner, Colby J.; Salali, Gül Deniz; Jackson, Andrew L. (2011) Feeding and non-feeding aggression can be induced in invasive shore crabs by altering food distribution, Behavior, Ecology and Sociobiolgy 65: 249-256

Taylor, David (2005) Predatory impact of the green crab (Carcinus maenas Linnaeus) on post-settlement winter flounder (Pseudopleuronectes americanus Walbaum) as revealed by immunological dietary analysis., Journal of Experimental Marine Biology and Ecology 324: 112-126

Taylor, Graeme M.; Keyghobadi, Nusha; Schmidt, Paul S. (2009) The geography of crushing: Variation in claw performance of the invasive crab Carcinus maenas, Journal of Experimental Marine Biology and Ecology 377: 48-53

Tepolt, C. K.; Darling, J. A.; Bagley, M. J.; Geller, J. B.; Blum, M. J.; Grosholz, E. D. (2009) European green crabs (Carcinus maenas) in the northeastern Pacific: genetic evidence for high population connectivity and current-mediated expansion from a single introduced source population, Diversity and Distributions 15: 997-1009

Tepolt, Carolyn; Somero, George M. (2014) Master of all trades: thermal acclimation and adaptation of cardiac function in a broadly distributed marine invasive species, the European green carb, Carcinus maenas, Journal of Experimental Biology 217: 1129-1138

Thresher, R.; Proctor, C.; Ruiz, G.; Gurney, R.; MacKinnon, C.; Walton, W.; Rodriguez, L.; Bax, N. (2003) Invasion dynamics of the European shore crab, Carcinus maenas, in Australia., Marine Biology 142: 867-876

Torchin, M. E.; Lafferty, K. D.; Kuris, A. M. (2002) Parasites and marine invasions., Parasitology 124: S137-S151

Troxel, Daniel J. (2010) Parasites of Largemouth Bass (Micropterus salmoides) in northern California , Humboldt State University, Arcata, California. Pp. <missing location>

Trussell, Geoffrey C.; Ewanchuk, Patrick J.; Bertness, Silliman, Brian R. (2004) Trophic cascades in rocky shore tide pools: distinguishing lethal and nonlethal effects., Oecologia 139: 427-432

Trussell, Geoffrey C.; Ewanchuk, Patrick J.; Catherine M. Matassa (2006) Habitat effects on the relative importance of trait and density-mediated indirect interactions., Ecology Letters 9: 1245-1252

Trussell, Geoffrey; Nicklin, Matthew O. (2002) Cue sensitivity, induced defense, and trade-offs in a marine snail., Ecology 83(6): 1635-1647

Tummon Flynn, Paula; Poirier, Luke A.; Beaulieu, Gabrielle ; Barrett, Timothy J. ; Cairns, David K.; Quijón, Pedro A. (2023) On the rebound: removal programs yield local‑scale benefits but do not sustainably suppress populations of invasive European green crabs (Carcinus maenas), Biological Invasions <missing volume>: Published online
https://doi.org/10.1007/s10530-023-03183-4

Turner, B. C.; de Rivera, C. E.; Grosholz, E. D.; Ruiz, G. M. (2016) Assessing population increase as a possible outcome to management of invasive species, Biological Invasions Published online: <missing location>

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/



USGS Nonindigenous Aquatic Species Program 2003-2022 Nonindigenous Aquatic Species Database. https://nas.er.usgs.gov/



Vader, Wim (1979) Strandkrabben Carcinus maenas in Finnmark., Fauna 32: 27-29

Veiga, Puri and 5 authors (2011) Does Carcinus maenas facilitate the invasion of Xenostrobus securis?, Journal of Experimental Marine Biology and Ecology 406: 14-20

Vera-Escalona, Iván; LGimenez, Lucas H.; Brante, Antonio (2023) Short-Term and Long-Term Predictions: Is the Green Crab Carcinus maenas a Threat to Antarctica and Southern South America under a Climate-Change Scenario?, Diversity 15: Published online
https://doi.org/10.3390/d15050632

Verdcourt, Nernard (1954) The Cowries of the East African Coast (Kenya, Tanganyika, Zanzibar and Pemba), Journal of the East African Society of Natural History 22: 129-147

Vermeij, G. J. (1982a) Phenotypic evolution in a poorly dispersing snail after arrival of a predator., Nature 299: 349-350

Vermeij, G. J. (1982b) Environmental change and the evolutionary history of the periwinkle (Littorina littorea) in North America, Evolution 36(3): 561-580

Verrill, A.E.; Smith, S.I. (1873) <missing title>, 1 Report of the United States Commission of Fish and Fisheries, <missing place>. Pp. 1-757

Wails, Christy N. and 11 authors (2021) Assessing changes to ecosystem structure and function following invasion by Spartina alterniflora and Phragmites australis: a meta-analysis, Biological Invasions 23: 2695-2709

Walton, William C.; MacKinnon, Craig; Rodriguez, Laura F.; Proctor, Craig; Ruiz, Gregory M. (2002) Effect of an invasive crab upon a marine fishery: green crab, Carcinus maenas, predation upon a venerid clam, Katelysia scalarina, in Tasmania (Australia)., Journal of Experimental Marine Biology and Ecology 272: 171-189

Walton, William C.; Ruiz, Gregory M.; Starr, Bethany A. (1999) Mitigating predation by the European green crab, Carcinus maenas, upon publicly maricultured quahogs, Mercenaria mercenaria., Journal of Shellfish Research <missing volume>: 305

Walton, William Cameron & Walton, William Charles (2001) Problems, predators, and perception: management of quahog (hardclam), Mercenaria mercenria, stock enrichment programs in southern New England, Journal of Shellfish Research 20(1): 127-134

Walton, William Cameron; Walton, William Charles (2001) Problems, predators and perception: management of Quahog (hardclam), Mercenaria, stock enhancement programs in southern New England., Journal of Shellfish Research 20(1): 127-134

Want, Andrew; Kakkonen, Jenni E. (2021) A new range-extending record of the invasive sea squirt S. clava in the north of Scotland, Marine Biodiversity Records 14(15): Published online

Ware, Chris et al. (2015) Biological introduction risks from shipping in a warming Arctic, Journal of Applied Ecology Published online: <missing location>

Washington Department of Fish and Wildlife 1997-1999 Green Crabs. <missing URL>



Wasson, Kerstin; Zabin, C. J.; Bedinger, L.; Diaz, M. C.; Pearse J. S. (2001) Biological invasions of estuaries without international shipping: the importance of intraregional transport, Biological Conservation 102: 143-153

Welch, Walter R. (1968) Changes in abundance of the green crab, Carcinus maenas (L.) in relation to recent temperature changes, Fishery Bulletin 67(2): 337-345

Wells, Christopher D. and 23 authors (2014) Report on the 2013 rapid assessment survey of marine species at New England bays and harbors, Massachusetts Office of Coastal Zone Management, Boston MA. Pp. 32

Wells, Fred E.; McDonald, Justin I.; Travers, Michael J. (2010) Absence of the European shore crab, Carcinus maenas, from the Fremantle marine area, Western Australia, Records of the Western Australia Museum 25: 378-381

Westfall, Kristen Marie; Therriault, Thomas W.; Abbott, Cathryn L. (2018) A new approach to molecular biosurveillance of invasive species using DNA metabarcoding, None <missing volume>: <missing location>
doi.org/10.1111/gcb.14886

White, K. L.; Townsend, S. M.; Reynolds, A. S. Barrington, E. B. (2010) Intertidal invertebrates of Scatarie Island: a preliminary species inventory and habitat description, Proceedings of the Nova Scotian Institute of Science 45(1): 9-17

Whitlatch, Robert B.; Osman, Richard (2000) Geographical distributions and organism-habitat associations of shallow water introduced marine fauna in New England., In: Pederson, Judith(Eds.) Marine Bioinvasions. , Cambridge MA. Pp. 61-65

Whitlow, Lindsay; Rice, Neil A.; Sweeney, Christine (2003) Native species vulnerability to introduced predators: testing an inducible defence and a refuge from predation., Biological Invasions 5: 23-31

Whitlow, W. Lindsay (2010) Changes in survivorship, behavior, and morphology in native soft-shell clams induced by invasive green crab predators, Marine Ecology 31: 418-430

Williams, Austin B. (1984) Shrimps, Lobsters, and Crabs of the Atlantic Coast of the Eastern United States, Maine to Florida, Smithsonian Institution Press, Washington, DC. Pp. <missing location>

Williams, Larissa M.; Nivison, Camilla L.; Ambrose, William G. Jr.; Dobbin, Rebecca; Locke, William L. V (2015) Lack of adult novel northern lineages of invasive green crab Carcinus maenas along much of the northern US Atlantic coast, Marine Ecology Progress Series 532: 153-159

Williams, P.J.; Floyd, T.A.; Rossong, M. A. (2006) Agonistic interactions between invasive green crabs, Carcinus maenas (Linnaeus), and sub-adult American lobsters, Homarus americanus (Milne Edwards)., Journal of Experimental Marine Biology and Ecology 329: 66-74.

Wiltshire, K.; Rowling, K.; Deveney, M. (2010) <missing title>, South Australian Research and Development Institute, Adelaide. Pp. 1-232

Wong, Melisa C.; Dowd, Michael (2014) Role of invasive green crabs in the foodweb of an intertidal sand flat determined from field observations and a dynamic simulation model, Estuaries and Coasts 37: 1004-1016

Yamada, Sylvia Behrens; Fisher, Jennifer L.; Kosro, P. Michael (2021) Relationship between ocean ecosystem indicators and year class strength of the invasive European green crab (Carcinus maenas), Progress in Oceanography 196(102618): Published online

Yamada, Sylvia Behrens; Davidson, Timothy Mathias; Fisher, Sarah (2010) Claw morphology and feeding rates of introduced European green crabs (Carcinus maenas L, 1758) and native Dungeness crabs (cancer magister Dana, 1852), Journal of Shellfish Research 29(2): 471-477

Yamada, Sylvia Behrens; Dumbauld, Brett R.; Kalin, Alex; Hunt, Christopher E.; Figlar-Barnes, Ron; Randall (2005) Growth and persistence of a recent invader Carcinus maenas in estuaries of the northeastern Pacific., Biological Invasions 7: 309-321

Yamada, Sylvia Behrens; Gillespie, Graham (2008) Will the European green crab (Carcinus maenas persist in the Pacific Northwest?, ICES Journal of Marine Science 65: 725-729

Yamada, Sylvia Behrens; Hauck, Laura (2001) Field identification of the European green crab species: Carcinus maenas and Carcinus aestuarii., Journal of Shellfish Research 20(3): 905-912

Yamada, Sylvia Behrens; Kosro, P. Michael (2010) Linking ocean conditions to year class strength of the invasive European green crab, Carcinus maenas, Biological Invasions 12: 1791-1804

Yamada, Sylvia Behrens; Peterson, William T.; Kosro, Michael (2015) Biological and physical ocean indicators predict the success of an invasive crab, Carcinus maenas, in the northern California Current, Marine Ecology Progress Series 537: 175-189

Zarrella-Smith, Katrina A.; Woodall, Jessica N.; Ryan, Athena ; Furey, Nathan B.; S.Goldstein, Jason (2022) Seasonal estuarine movements of green crabs revealed by acoustic telemetry, Marine Ecology Progress Series 681: 129-143

Zenetos, Argyro Golani, Dani (2003) CIESM Atlas of Exotic Species in the Mediterranean: Molluscs, CIESM Publishers, <missing place>. Pp. <missing location>

Zetlmeisel, C.; Hermann, J.; Petney, T.; Glenner, H.; Griffiths, C.; Tarachewski, H. (2011) Parasites of the shore crab Carcinus maenas: implications for reproductive potential and invasion success, Parasitology 138: 398-401

Zhang, Junlong; Yurchenko, Olga V.; Konstantin, A.; Kalachev, Alexander V. Nekhaev, Ivan O. Aguilar, Robert Zhan, Zifeng Ogburn, Matthew B. (2018) A tale of two soft-shell clams: an integrative taxonomic analysis confirms Mya japonica as a valid species distinct from Mya arenaria (Bivalvia: Myidae), Zoological Journal of the Linnean Society 184: 605-622