''Pagurus bernhardus'' is the common marine

hermit crab Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an as ...

Europe's Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entire ...

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

coasts. It is sometimes referred to as the common hermit crab or soldier crab. Its

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

reaches long, and is found in both rocky and sandy areas, from the

Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...

waters of

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...

Svalbard Svalbard ( , ), also known as Spitsbergen, or Spitzbergen, is a Norwegian archipelago in the Arctic Ocean. North of mainland Europe, it is about midway between the northern coast of Norway and the North Pole. The islands of the group range ...

and

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

as far south as southern

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

, but its range does not extend as far as the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

. It can be found in pools on the upper shore and at the mean tide level down to a depth of approximately , with smaller specimens generally found in rock pools around the middle shore and lower shore regions, with larger individuals at depth. ''P. bernhardus'' is an

omnivorous An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutri ...

detritivore that opportunistically scavenges for carrion, and which can also

filter feed Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...

when necessary. FMIB 52669 Pagurus bernhardus, the hermit-crab-retouched

''Pagurus bernhardus'' uses shells of a number of

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

species for protection, including ''

Littorina littorea The common periwinkle or winkle (''Littorina littorea'') is a species of small edible whelk or sea snail, a marine gastropod mollusc that has gills and an operculum, and is classified within the family Littorinidae, the periwinkles.Reid, David ...

'', '' Littorina obtusata'', '' Nassarius reticulatus'', ''

Gibbula umbilicalis ''Steromphala umbilicalis'', common name the flat top shell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.MolluscaBase eds. (2020). MolluscaBase. Steromphala umbilicalis (da Costa, 1778). Acces ...

'', ''

Nucella lapillus The dog whelk, dogwhelk, or Atlantic dogwinkle (''Nucella lapillus'') is a species of predatory sea snail, a carnivorous marine gastropod in the family Muricidae, the rock snails. ''Nucella lapillus'' was originally described by Carl Linnaeus ...

'' and ''

Buccinum ''Buccinum'' is a genus of medium-sized sea snails, marine gastropod molluscs in the family Buccinidae, the true whelks.Gofas, S.; Bouchet, P. (2014). Buccinum Linnaeus, 1758. Accessed through: World Register of Marine Species at http://www. ...

''. In the warmer parts of its range, the sea anemone ''

Calliactis parasitica ''Calliactis parasitica'' is a species of sea anemone associated with hermit crabs. It lives in the eastern Atlantic Ocean and Mediterranean Sea at depths between the intertidal zone and . It is up to in size, with up to 700 tentacles, and is ...

'' is often found growing on the shell occupied by ''Pagurus bernhardus''. In colder waters, this role is filled by '' Hormathia digitata''. Hermit crabs fight one another for gastropod shells and have a preference for shells of certain species.

References

External links

* *{{cite news , url=http://www.livescience.com/animals/080312-crab-personality.html , title=Some crabs crabbier than others , publisher=

LiveScience Live Science is a science news website run by Future via Purch, which it purchased from Imaginova in 2009. Stories and editorial commentary are typically syndicated to major news outlets, such as Yahoo!, MSNBC, AOL, and Fox News.{{fact, date=Marc ...

, date=March 12, 2008 , author=Charles Q. Choi Hermit crabs Crustaceans of the Atlantic Ocean Crustaceans described in 1758 Taxa named by Carl Linnaeus