Green Crab

Carcinus maenas

Biology 3

The shore crab feeds on invertebrates including worms, molluscs and crustaceans Small molluscs and barnacles are taken by young crabs (2). Breeding peaks in summer, and mating can only take place shortly after the female moults; the male finds a female before she is due to moult, and carries her around underneath his body for a number of days (2). After the moult, copulation occurs. The female creates a cavity by burrowing in the sand; she lays the eggs whilst positioned over this cavity, attaches them to her walking legs and carries them around for several months (2). After hatching, the larvae are planktonic for 2-3 years. They then settle as young crabs, and reach maturity after around a year (2).

Description 4

 The shore crab has a shell (carapace) that is much broader than long (up to 8 cm across). The front of the carapace is serrated with five teeth on either side and three rounded lobes between the eyes. The first pair of legs (pereopods) have well developed pincers (chelae). Its colour is highly variable from dark green to orange and red. Variation in colour may be due to the stage of the life cycle or the habitat. Juveniles in particular display a wide range of mottled patterns.

Food habits 5

The green crab enjoys a variety of different foods. These foods include clams, oysters, mussels, and other small crabs. The green crab is very dexterous and has many ways in which to open up the shellfish on which it feeds. The green crab is known as a very vicious carnivore that will consume anything it can get its claws on.(Holden 1997, Washington Dept. 1997)

Geographic range 6

The green crab is native to the Atlantic Ocean off of the coast of Europe. Around the early eighteen hundreds the green crab was first seen on the Atlantic coast of North America. The crab can now be found from ranging from as far north as Nova Scotia and to the southern state of Virginia. In the late eighties, the crab mysteriously showed up in the San Francisco Bay area, and has since been spotted as far north as Oregon. This crab has also been found in such areas as far reaching as the continent of Australia.(Deegan, et al 1999, Holden 1997)

Biogeographic Regions: atlantic ocean (Native ); pacific ocean (Native )

Habitat 7

The green crab resides among tidal marshes, sandflats, and coasts with a rocky terrain. They tend to stay around these areas for protection from predators, and to be close to a readily available food supply.(Holden 1997, Deegan, et al 1999)

Aquatic Biomes: coastal

Sources and Credits

  1. (c) Nuno Barreto, some rights reserved (CC BY-NC-SA), http://www.flickr.com/photos/95962912@N00/80843042
  2. (c) Biopix, some rights reserved (CC BY-NC), http://www.biopix.com/photos/Carcinus-maenas-00016.JPG
  3. (c) Wildscreen, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/5670850
  4. (c)  The Marine Biological Association of the United Kingdom, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/16196738
  5. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18638373
  6. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18638369
  7. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18638370

More Info

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