BIOTIC

BIOTIC Species Information for Cancer pagurus

Researched by

Ken Neal & Emily Wilson

Data supplied by

MarLIN

Refereed by

This information is not refereed.

Taxonomy

Scientific name

Cancer pagurus

Common name

Edible crab

MCS Code

S1566

Recent Synonyms

None

Phylum

Crustacea

Subphylum

Superclass

Class

Eumalacostraca

Subclass

Eucarida

Order

Decapoda

Suborder

Pleocyemata

Family

Cancridae

Genus

Cancer

Species

pagurus

Subspecies

Additional Information

Also known as the brown crab.

Taxonomy References

Howson & Picton, 1997, Anosov, 2000.,

General Biology

Growth form

Articulate

Feeding method

Predator

Mobility/Movement

Crawler

Environmental position

Epibenthic

Typical food types

A variety of live molluscs and crustaceans as well as carrion.

Habit

Free living

Bioturbator

Not relevant

Flexibility

None (< 10 degrees)

Fragility

Intermediate

Size

Medium-large(21-50cm)

Height

Insufficient information

Growth Rate

0.1-1 cm/year

Adult dispersal potential

1km-10km

Dependency

Independent

Sociability

Solitary

Toxic/Poisonous?

General Biology Additional Information

Feeding
Cancer pagurus is a large crab typical of hard and soft bottom communities. It is an active predator and consumes a variety of crustaceans (e.g. the green shore crab Carcinus maenas, the broad clawed porcelain crab Porcellana platycheles, the long clawed porcelain crab Pisidia longicornis, the hairy crab Pilumnus hirtellus and the squat lobster Galathea squamifera) and will also eat smaller members of their own species (conspecifics) (Lawton, 1989). Cancer pagurus also consumes a variety of molluscs e.g. the dog whelk Nucella lapillus, the winkle Littorina littorea (Lawton & Hughes, 1985), razor shells Ensis spp. (Hall et al., 1991), the blue mussel Mytilus edulis, the common cockle Cerastoderma edule and the oyster Ostrea edulis (Mascaro & Seed, 2001). Motile prey may be stalked and pounced upon, trapped under the abdomen and crushed with the chelae. Some prey is also ambushed from shelters under rocks (Lawton, 1989). In sediments Cancer pagurus may dig large pits to access bivalve molluscs such as Ensis sp. (Hall et al., 1991) and Lutraria lutraria. Cancer pagurus is mainly nocturnal, presumably to reduce predation by wolf fish, seals and cod (Skajaa et al., 1998).

Growth
Juveniles settle in the intertidal zone in late summer/ early autumn (Bennett, 1995) and remain there until they reach a carapace width (CW) of 6-7 cm (which takes about 3 years) before they move to subtidal areas (Regnault, 1994). Growth rate varies with age and gender. Between years 4-8 of a male crabs life, it grows at about 1 cm CW per year. After the 8th year, growth rate slows gradually to about 2 mm per year between its 16th and 20th years. Female growth rate is less, at about 0.5 cm per year between years 4 and 8, declining to 0.1 cm per year between years 16 and 20 (Bennett, 1979).

Size can be related to depth. In less than 25 m of water, males and females have a mean CW of 14 cm. Between 25 and 55 m, males are on average 17 cm CW and females 15.8 cm, over 55 m these sizes increase to 18 cm CW for males and 17 cm CW for females (Brown & Bennett, 1980).

Biology References

Edwards, 1979, Bennett, 1995, Lawton, 1989, Lawton & Hughes, 1985, Hall et al., 1991, Mascaro & Seed, 2001, Skajaa et al., 1998, Regnault, 1994, Bennett, 1979, Brown & Bennett, 1980, Bennett & Brown, 1983,

Distribution and Habitat

Distribution in Britain & Ireland

All British and Irish coasts.

Global distribution

From Norway throughout the North Sea and English Channel to the coast of Portugal. Cancer pagurus may penetrate into the Mediterranean Sea and occur in the Black Sea (Anosov, 2000) but this is yet to be confirmed.

Biogeographic range

Not researched

Depth range

From intertidal down to 100m

Migratory

Non-migratory / Resident

Distribution Additional Information

Adult Cancer pagurus cannot tolerate salinities of 17 psu or lower whereas young (5-10 cm CW) can tolerate reduced salinities for extended periods (Wanson et al., 1983).

Substratum preferences

Cobbles
Gravel / shingle
Pebbles
Sandy mud
Muddy sand
Fine clean sand
Coarse clean sand
Bedrock
Muddy gravel

Physiographic preferences

Offshore seabed
Strait / sound

Biological zone

Mid Eulittoral
Lower Eulittoral
Sublittoral Fringe
Upper Infralittoral
Lower Infralittoral
Upper Circalittoral
Lower Circalittoral

Wave exposure

Exposed
Moderately Exposed

Tidal stream strength/Water flow

Moderately Strong (1-3 kn)
Weak (<1 kn)

Salinity

Variable (18-40 psu)
Full (30-40 psu)

Habitat Preferences Additional Information

Distribution References

Wanson et al., 1983, Bennett & Brown, 1983, Anosov, 2000.,

Reproduction/Life History

Reproductive type

Gonochoristic

Developmental mechanism

Planktotrophic

Reproductive Season

Winter

Reproductive Location

As adult

Reproductive frequency

Annual episodic

Regeneration potential

Life span

21-50 years

Age at reproductive maturity

6-10 years

Generation time

11-20 years

Fecundity

250,000 - 3,000,000 eggs per female

Egg/propagule size

Insufficient information

Fertilization type

Internal

Larvae/Juveniles
Larval/Juvenile dispersal potential	>10km	Larval settlement period	Insufficient information
Duration of larval stage	1-6 months

Reproduction Preferences Additional Information

Mating is by copulation in spring and summer and occurs shortly after the female has moulted (Brown & Bennett, 1980). Females are 'berried' (carrying eggs under the abdomen) for 6-9 months after copulation and release the larvae in late spring/early summer (Thompson et al., 1995). Berried females do not feed, remaining in pits dug in the sediment or under rocks and are unlikely to be caught in a baited pot. As a result, fishing pressure does not affect larval supply (Howard, 1982). Fecundity is between 0.25 and 3 million eggs per female depending on size (Bennett, 1995). Females can store sperm and berried females retained after an experiment went on to produce viable larvae in the following reproductive season without moulting or copulating (Naylor et al., 1999). In the North Sea, berried females migrate offshore to release larvae and then move back inshore to feed (see larval general biology; Nichols et al., 1982).

Reproduction References

Edwards, 1979, Bennett, 1995, Nichols et al., 1982, Brown & Bennett, 1980, Howard, 1982, Thompson et al., 1995, Naylor et al., 1999,