Carcinus maenas

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

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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 (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 occurring 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 Islands, Padilla Bay, Dungeness Spit  and Lummi Seafood Hatchery Bay (Yamada et al. 2017, University of Washington 2017; Associated Press 2021). In 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 chromosomal inversion permitted local temperature adaptation despite 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.

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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.

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Taxonomy

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

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Habitats

General Habitat	Unstructured Bottom	None
General Habitat	Grass Bed	None
General Habitat	Marinas & Docks	None
General Habitat	Rocky	None
General Habitat	Salt-brackish marsh	None
General Habitat	Coarse Woody Debris	None
General Habitat	Oyster Reef	None
Salinity Range	Mesohaline	5-18 PSU
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Tidal Range	Low Intertidal	None
Tidal Range	Mid Intertidal	None
Tidal Range	High Intertidal	None
Vertical Habitat	Epibenthic	None

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Life History

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Tolerances and Life History Parameters

Minimum Temperature (ºC)	-1	None
Maximum Temperature (ºC)	35	Experimental, 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 (‰)	4	Salinity 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 (‰)	54	Broekhuysen 1936, Experimental. Elevated salinities are possilbe in isolated tidepools, under a hot sun.
Minimum Reproductive Temperature	6	Ovigerous females, 6-10 C, Placentia Bay, Newfoundland (Best et al. 2017)
Maximum Reproductive Temperature	17	Williams 1984
Minimum Reproductive Salinity	13	Broekhuysen 1936
Maximum Reproductive Salinity	54	Broekhuysen 1936
Minimum Duration	25	Release to first crab- Berrill 1982; Lipski, unpublished data
Maximum Duration	90	Release to first crab- Berrill 1982; Lipski, unpublished data
Minimum Length (mm)	19	For adult female, 25 mm for males. Broekhuysen 1936; Crothers 1967, Crothers 1968; Berrill 1982
Maximum Length (mm)	86	For 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).

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Regional Impacts

NA-ET3	Cape Cod to Cape Hatteras		Ecological Impact	Predation
Carcinus maenas is a major predator on bivalves in Buzzards Bay-Vineyard Sound, Narragansett Bay and Long Island Sound. Field observations indicate that the abundance of C. maenas and its spread into estuaries decreases south of Long Island (de Rivera et al. 2005b). Carcinus maenas is a major predator in invertebrate communities in Buzzards Bay and Vineyard Sound. Studies of its effects on Mercenaria mercenaria (Quahaug; Hard Clam) populations in coastal lagoons ("salt ponds") on Martha's Vineyard indicate that C. maenas is a major source of mortality to clam populations. Evidence for this includes caging (predator exclusion) and massive removal experiments (Walton et al. 1999; Walton and Walton 2001; Walton et al. 2002). In the Narragansett Bay region, gut content studies indicate that Mytilus edulis was the predominant food of adult C. maenas in the Pettaquamscutt River estuary, while juveniles fed mostly on small crustaceans (Ropes 1989). In field experiments at Avery Point, Long Island Sound, C. maenas fed on young mussels at a higher rate than the recently introduced crab, Hemigrapsus sanguineus (Asian Shore Crab), but the much higher densities of H. sanguineus now make it the more important predator in the rocky intertidal (Lohrer and Whitlach 2002). Predation by adult Carcinus on juvenile Argopecten irradians (Bay Scallop) in Long Island Sound was studied experimentally in laboratory experiments. Carcinus were one of several predators responsible for mortality of young scallops in field tethering experiments, but juvenile mud crabs were considered to be the most important predators, because of their ability to climb eelgrass blades where young Argopecten were attached (Pohle et al. 1991). Taylor (2005) found that Green Crabs in Long Island Sound had a small predatory impact (1-8% of daily mortality) on newly settled juveniles of the Winter Flounder (Pseudopleuronectes americanus).
NA-ET3	Cape Cod to Cape Hatteras		Economic Impact	Fisheries
Carcinus maenas is a major predator of commercial shellfish in Buzzards Bay-Vineyard Sound, Narragansett Bay and Long Island Sound (Walton et al. 1999), but its abundance and commercial importance appears to decrease sharply in the southern half of its range (de Rivera et al. 2005b). Carcinus maenas is a major predator on commercial shellfish in Buzzards Bay and Vineyard Sound. Studies of its effects on Mercenaria mercenaria (Quohaug; Hard Clam) populations in coastal lagoons ("salt ponds") on Martha's Vineyard indicate that C. maenas is a major source of mortality to clam populations. Evidence for this includes caging (predator exclusion) and massive removal experiments (Walton et al. 1999; Walton and Walton 2001). This species is well-known as a shellfish pest here. Carcinus maenas preys on bivalves in Long Island Sound. Predation by adult Carcinus on juvenile Argopecten irradians (Bay Scallop) was studied experimentally in laboratory experiments. Carcinus was one of several predators responsible for mortality of young scallops in field tethering experiments, but juvenile mud crabs were considered to be the most important predators, because of their ability to climb eelgrass blades where young Argopecten were attached (Pohle et al. 1991). Intense predation by green crabs on adult scallops has been observed in Connecticut waters (Morgan et al. 1980, cited by Pohle et al. 1991). Carcinus maenas is locally regarded as a serious predator of commercial shellfish (Ropes 1989). It is locally caught and sold as bait for fishing.
NA-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Predation
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 obtusata, Nucella 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-ET2	Bay of Fundy to Cape Cod		Economic Impact	Fisheries
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-V	Northern California to Mid Channel Islands		Ecological Impact	Predation
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-V	Northern California to Mid Channel Islands		Ecological Impact	Competition
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-V	Northern California to Mid Channel Islands		Ecological Impact	Trophic 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-IV	None		Ecological Impact	Competition
Competition with native crabs is expected to be limited because of differences in habitat use (Griffiths et al. 1992).
AUS-IX	None		Ecological Impact	Predation
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-IX	None		Ecological Impact	Competition
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-IX	None		Economic Impact	Fisheries
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 Impact	Fisheries
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 Impact	Predation
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-ET1	Gulf of St. Lawrence to Bay of Fundy		Ecological Impact	Predation
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).
P110	Tomales Bay		Ecological Impact	Predation
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).
P110	Tomales Bay		Ecological Impact	Trophic 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).
N180	Cape Cod Bay		Ecological Impact	Predation
Carcinus maenas was the most voracious predator of egg capsules of Ilyanassa obsoleta (Brenchley 1982).
NA-S3	None		Economic Impact	Fisheries
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-S3	None		Ecological Impact	Predation
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 Impact	Predation
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 Impact	Competition
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 Impact	Trophic 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-V	Northern California to Mid Channel Islands		Economic Impact	Fisheries
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 Impact	Fisheries
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).
M040	Long Island Sound		Ecological Impact	Predation
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.
M040	Long Island Sound		Economic Impact	Fisheries
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).
N170	Massachusetts Bay		Ecological Impact	Predation
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 Impact	Predation
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 Impact	Predation
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).
N010	Passamaquoddy Bay		Ecological Impact	Predation
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).
M020	Narragansett Bay		Ecological Impact	Predation
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-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Trophic 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-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Competition
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).
N130	Great Bay		Ecological Impact	Predation
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.
N130	Great Bay		Ecological Impact	Competition
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-ET3	Cape Cod to Cape Hatteras		Ecological Impact	Competition
In laboratory trials, C. maenas frequently outcompeted Callinectes sapidus of equal size for food and won fights over food more frequently than C. sapidus or Hemigrapsus sanguineus (MacDonald et al. 2007). However, predation by adult C. sapidus may be limiting the southern range expansion of C. maenas (de Rivera et al. 2005b).
NA-ET1	Gulf of St. Lawrence to Bay of Fundy		Ecological Impact	Competition
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-ET1	Gulf of St. Lawrence to Bay of Fundy		Ecological Impact	Food/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-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Food/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 Impact	Food/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).
N070	Damariscotta River		Ecological Impact	Predation
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-IV	Puget Sound to Northern California		Ecological Impact	Predation
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.
N120	Wells Bay		Ecological Impact	Predation
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).
N170	Massachusetts Bay		Ecological Impact	Trophic 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-IV	None		Ecological Impact	Predation
Carcinus maenas could be an important predator in protected waters (Griffiths et al. 1992).
P210	Yaquina Bay		Ecological Impact	Predation
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.
N070	Damariscotta River		Ecological Impact	Trophic 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).
N080	Sheepscot Bay		Ecological Impact	Predation
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).
N020	Englishman/Machias Bay		Ecological Impact	Predation
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).
N020	Englishman/Machias Bay		Economic Impact	Fisheries
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-S3	None		Ecological Impact	Habitat 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-ET1	Gulf of St. Lawrence to Bay of Fundy		Ecological Impact	Habitat 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).
N100	Casco Bay		Ecological Impact	Habitat 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).
N100	Casco Bay		Ecological Impact	Predation
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-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Habitat 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-ET1	Gulf of St. Lawrence to Bay of Fundy		Ecological Impact	Trophic 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).
N180	Cape Cod Bay		Ecological Impact	Competition
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).
N180	Cape Cod Bay		Ecological Impact	Trophic 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-III	Alaskan panhandle to N. of Puget Sound		Ecological Impact	Habitat 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-III	Alaskan panhandle to N. of Puget Sound		Ecological Impact	Herbivory
In experiments, in Barkely Sound, Briitsh Columbia, Green Crabs shredded Eelgrass blades, but also directly consumed rhizomes (Howard et al. 2019).
NA-S3	None		Ecological Impact	Food/Prey
American Lobsters (Homarus americanus) in lobster traps prey on both Green Crabs and Rock Crabs (Cancer irroratus) (Zargarpour et al. 2020).
SA-I	None		Ecological Impact	Food/Prey
Carcinus maenas is a food item (though not a major one) for the native Kelp Gull (Larus dominicus,(Yorio et al. 2020).
NEP-III	Alaskan panhandle to N. of Puget Sound		Ecological Impact	Competition
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).
OR	Oregon		Ecological Impact	Predation
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.
CA	California		Ecological Impact	Competition
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).
CA	California		Ecological Impact	Predation
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).
CA	California		Ecological Impact	Trophic 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).
CA	California		Economic Impact	Fisheries
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).
MA	Massachusetts		Ecological Impact	Competition
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).
MA	Massachusetts		Ecological Impact	Predation
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).
MA	Massachusetts		Ecological Impact	Trophic 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).
MA	Massachusetts		Economic Impact	Fisheries
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).
ME	Maine		Ecological Impact	Habitat 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).
ME	Maine		Ecological Impact	Predation
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).
ME	Maine		Ecological Impact	Trophic 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).
ME	Maine		Economic Impact	Fisheries
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).
NH	New Hampshire		Ecological Impact	Food/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).
NH	New Hampshire		Ecological Impact	Predation
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-S3	None		Ecological Impact	Herbivory
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-S3	None		Ecological Impact	Herbivory
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).

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

Anderson, Dean P.; Pepper, Margaret A.; Travers, Shelby; Michaels, Trevor A.; Sullivan, Kevin · Ramsey, David S. L. (2022) Confirming the broadscale eradication success of nutria (Myocastor coypus) from the Delmarva Peninsula, USA , Biological Invasions 24: 509–3521

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 2003-2024 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

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