Eats on dead organic material. A long foreplay, to ensure the baring of the abdomen was not vain. The mating only lasts less than a minute.

In Britain, small hermit crabs are a common feature of the shore, where they frequently adopt the shells of edible periwinkles (Littorina littorea), flat periwinkles (Littorina obtusata) and dog whelks (Nucella lapidus). In deeper water, the shells of the whelk (Buccinum) are often occupied. Occasionally, if two hermit crabs meet, one will attempt to 'steal' the other's shell by forcibly evicting the current owner. The common hermit crab is an omnivorous scavenger, and can also obtain food by filtering organic particles from the water (4). Reproductive activity tends to peak in January and February in populations dwelling on the shore, but in those living in deeper water, females have been found carrying eggs throughout the year (4). The female carries the eggs for around two months, after which time the pelagic larvae persist for a number of weeks. Maturity is typically reached before one year of age (4). A number of animals are associated with this hermit crab, particularly the sea anemone Calliactis parasitica, which lives on the shell of the hermit crab, and provides increased protection against predators, receiving improved food collection in return (4). This is known as a symbiotic relationship, as both parties benefit from the association (4). A parasitic barnacle (Peltogaster paguri) is often seen under the abdomen of the hermit crab as a yellowish mass, which is often confused with the crab's eggs (4).

 A large hermit crab with a carapace length that reaches 35mm. It is reddish in colour and will occupy any suitable shell such as Buccinum undatum. Both pincers are covered with thick, pointed protrusions, the massive right pincer has two rows of large protrusions and is devoid of bristles.

Despite the common name, hermit crabs are related more closely to lobsters than to crabs. They lack a hard carapace, and adopt the empty shells of gastropod molluscs (such as whelks), carrying them around and swapping them for a larger shell as they grow (3). When seen out of a shell, hermit crabs have a bizarre appearance; the soft abdomen is twisted, which allows it to fit into the coils of the gastropod shell (4). The common hermit crab is typically reddish or brownish in colour, and has two pincers on the first pair of walking legs. The right pincer is larger than the left, and both have a rough, granular surface (4).

Azores Exclusive Economic Zone, Belgian Exclusive Economic Zone, Birkenfels (shipwreck), Bray-Dunes, British Isles, De Haan, De Panne, Dutch Exclusive Economic Zone, European waters (ERMS scope), Irish Exclusive economic Zone, North Sea, North West Atlantic, Norwegian Exclusive Economic Zone, Oostende, Oosterschelde, Portugese Exclusive Economic Zone, United Kingdom Exclusive Economic Zone, Voordelta, Wadden Sea, Westerschelde, Wimereux, Zeebrugge, Zeeland

Common and widespread in north-west Europe, and found around all of the coasts of Britain (2).

Largest and most common heremit crab in our region. An average length of 10 cm, carapace of 3,5 cm. Color: red-orange. Only two out of four legs well developed. Only one cheliped, or scissor (almost always the right one) is much bigger. The pair of scissors always bear length ridges with a row of knobs on top. Eyes positioned on a stalk.

Known from the nearshore.

In the intertidal area and beneath. On rocky shores, shell bottoms and sandy and silty sediments, but never muddy. Among vegetation, as seagrass beds. Adults in shell of whelk, juveniles on beaches, often in shell of (peri)winkle and moonshells

Depth range based on 1728 specimens in 1 taxon.
Water temperature and chemistry ranges based on 742 samples.

Environmental ranges
  Depth range (m): 0 - 375
  Temperature range (°C): 6.433 - 12.348
  Nitrate (umol/L): 1.402 - 16.868
  Salinity (PPS): 22.343 - 35.388
  Oxygen (ml/l): 5.262 - 7.118
  Phosphate (umol/l): 0.239 - 0.890
  Silicate (umol/l): 0.987 - 11.419

Graphical representation

Depth range (m): 0 - 375

Temperature range (°C): 6.433 - 12.348

Nitrate (umol/L): 1.402 - 16.868

Salinity (PPS): 22.343 - 35.388

Oxygen (ml/l): 5.262 - 7.118

Phosphate (umol/l): 0.239 - 0.890

Silicate (umol/l): 0.987 - 11.419
 
Note: this information has not been validated. Check this *note*. Your feedback is most welcome.

 Found on rocky and sandy substrata from mean tide level to 140 m.

Inhabits both rocky and sandy areas from the shore to depths of 140m (4).

In Great Britain and/or Ireland:
Animal / parasite / ectoparasite
Athelges paguri ectoparasitises gill chamber of Pagurus bernhardus
Other: unusual host/prey

Animal / parasite / endoparasite
adult of Peltogaster paguri endoparasitises body of Pagurus bernhardus

Animal / parasite / ectoparasite
Pseudione hyndmanii ectoparasitises branchial cavity of Pagurus bernhardus

Animal / parasite / ectoparasite
Pseudione proxima ectoparasitises branchial cavity of Pagurus bernhardus

The following is a representative barcode sequence, the centroid of all available sequences for this species. 

 
There are 9 barcode sequences available from BOLD and GenBank.  Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.  See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
 

Download FASTA File

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 9
Species: 31
Species With Barcodes: 1

Common and widespread (2).

Not currently threatened.

Specific conservation action has not been targeted at this species.