Marine Hermit Crabs

Hermit crabs are marine crabs of the family Paguridae, the most common being Pagurus bernhardus, and are found off of the coast of Europe and the Americas (“Hermit Crabs”). There are two main families of hermit crabs: marine hermit crabs and land hermit crabs. Marine hermit crabs mostly live underwater in various depths of saltwater, while land hermit crabs mostly live on land, but can also survive under water. Land hermit crabs are found in tropical areas, more specifically those of the Indo-Pacific, western Atlantic, and western Caribbean. These crabs reside close to the shoreline, since they require access to both land and water. Marine hermit crabs are found further away from the shore, as they spend the majority of their time under water.

The front half of the crabs, in contrast, are covered with a hard exoskeleton, similar to those of other crabs, with strong claws used for defense, and food collection (12). Hermit crabs also have eyes with acute vision, and two pairs of antennae, the longer of which is used for feeling, and the shorter pair for smelling and tasting. Their exoskeletons are also covered in tiny sensory hairs that are used as vibration sensors (“Crabs” 1092). These hermit crabs have adapted to their environment through their gills that have highly vascularized areas for gas exchange, which allow them to breathe both on land and in

These sea anemones often adorn the shells of the hermit crabs, and fends off small predators with its stinging cells. In return, the sea anemones obtain food scraps from the crab. The relationship between these two species are so important, that when hermit crabs switch shells, they will coax and remove the anemone from the old shell to their new one (“Crabs” 1093). In addition to sea anemone, many other types of epifauna also adorn the shells of hermit crabs, and it was hypothesized that the type of shell affects the biodiversity of the fauna. Two species of the hermit crab, the Pagurus bernhardus and the Pagurus pubescens in Arctic waters, were studied and the biodiversity of the epifauna on the shells of these hermit crabs were explored. It was determined that the location was an important determining factor in not only the Arctic waters on the Svalbard, but also in Norwegian fjords. It was hypothesized however, that other factors other than location were more integral to the biodiversity of the epifauna on the shells of the Norwegian crabs. Shell area and type were less determining factors, however, larger and more irregular shaped shells contained more diverse species. The species of the crab also served as a determining factor, but it was predicted that the location that these crabs resided was the cause of this