European hermit crab
The European hermit crab is a coastal marine species found in the waters of Europe, known for its unique behavior of inhabiting the empty shells of other sea creatures. This crab, which can grow between 1 1/3 to 4 inches in length, features a combination of soft and hard body parts, with a slender form resembling that of shrimp. Young hermit crabs typically reside along rocky shorelines, while adults tend to move further offshore. They are omnivorous, feeding on both plant matter and flesh, and are primarily solitary, though they may sometimes gather to feed.
Reproduction occurs year-round, with females carrying hundreds of sticky eggs attached to their tails. The larval stage lasts about 43 days before they settle on the ocean floor and begin their maturation process. While the shells provide protection from most predators, they remain vulnerable to larger species, such as octopuses and squids, as well as threats from environmental pollution and human activities. Additionally, hermit crabs face competition for shells, as larger crabs may forcibly displace them. The European hermit crab also engages in symbiotic relationships, allowing certain worms to share its shell and hosting sea anemones that can offer some protection from predators.
On this Page
European hermit crab
The European hermit crab lives in the empty shells of other sea creatures. Although it does not live with other hermit crabs, it may share the inside of its shell with certain species of worms and other crustaceans and let a sea anemone attach to the outside of the shell.
Kingdom: Animalia
Phylum: Arthropoda
Class: Malacostraca
Order: Decapoda
Family: Paguridae
Genus: Pagurus
Species: Bernhardus
The European hermit crab is one of several hermit crab species that makes its home in the coastal waters of Europe. When it is young it lives along rocky shorelines under stones, in crevices, and in tidal pools. As an adult, it moves farther offshore. Both young and adult hermit crabs make their homes in the empty shells of other marine, or ocean-dwelling, creatures.
Unlike other crab species, the European hermit crab has soft and hard body parts. The abdomen, or tail section, is soft, while the thorax, or mid-body section, the legs, and the head have hard, shell-like coverings. It is a slender creature with a small head joined to its rounded thorax, which connects to a long, round, narrow tail with several flexible segments. In general, it looks similar to many species of shrimp. The European hermit crab may be different shades of red or pink with white and is between 1 1/3 and 4 inches (35 and 100 millimeters) long. Its antennae and eyes, at the ends of short stalks, extend from its head.
A male and female European hermit crab may mate year-round, and the female carries hundreds of eggs on her tail. The sticky eggs attach to the tiny leg-like swimmerets on her abdomen and tail. When the eggs hatch 43 days later, they are free-swimming larvae. After they molt, or shed, their skins four times, the young become adults and settle to the bottom. Only a few crabs survive to this point in their lives. The surviving crabs search for empty shells in which to live, since their soft bodies are without defense against attack. They can mate for the first time when they are around one year old.
The adult European hermit crab is safe in its shell from most predators, but octopuses and squids can crush its shell to eat the crab. Sometimes, a larger and stronger hermit crab may pull a smaller and weaker crab from its shell so it can take the shell for itself. The crab is most in danger when it outgrows one shell and must move to a larger shell. Threats common to all hermit crabs are pollution and people. Natural predators include North Pacific octopus (Octopus apollyon), red rock crab (Cancer productus), ballan wrasse (Labrus bergylta), and lingcod (Ophiodon elongates).
The European hermit crab is an omnivore, or an animal that eats plant matter and flesh. It lives and feeds alone both during the day and at night. Sometimes it gathers with other hermit crabs to feed at particular sites. The European hermit crab may share the inside of its shell with certain worms and let a sea anemone attach to the outside. The anemone may provide some protection since other predators stay away from the stinging tentacles of the anemone.
Bibliography
"Common Hermit Crab." British Sea Fishing, britishseafishing.co.uk/common-hermit-crab. Accessed 15 Apr. 2024.
Wang, Kathleen. "Pagurus Bernhardus." Animal Diversity Web, animaldiversity.org/accounts/Pagurus‗bernhardus. Accessed 15 Apr. 2024.