Atlantic Hermit Crab

§ Quick facts

§ Encyclopedia

Pagurus longicarpus, the long-wristed hermit crab or the long-clawed hermit crab, is a common hermit crab found along the Atlantic and Gulf coasts of the United States and the Atlantic coast of Canada.

Source: Wikipedia — Pagurus longicarpus · Licensed under CC BY-SA 4.0

§ Identification

Field marks. Small crab with elongated asymmetrical abdomen tucked into snail shell. Two large claws (right typically larger); long antennae; eyes on stalks.

Similar species. Other hermit crab species (different sizes, shell preferences). True crabs (symmetrical, no shell-dwelling).

Voice. N/A

§ Diet & behavior

Diet. Detritus, algae, dead animal matter, small invertebrates. Important shoreline scavengers.

Behavior. Soft asymmetrical abdomen requires protection of an empty gastropod shell. As crab grows, it must find progressively larger shells — when a new desirable shell appears, hermit crabs form "vacancy chains," lining up by size to swap shells in sequence. Threatened by plastic pollution: crabs sometimes try to occupy plastic bottle caps and become trapped.

§ Range

Atlantic coast from Nova Scotia to Florida

§ Habitat

Sandy and muddy intertidal areas, shallow bays

§ Threats

Coastal development, plastic pollution (hermit crabs sometimes shelter in plastic caps that trap them), warming oceans.

§ Conservation status

According to the IUCN Red List, the atlantic hermit crab is currently classified as Least Concern.

§ What helps

Skip beach plastic. Don't collect from tidepools. Support coastal habitat protection.

§ Further reading

• Wikipedia — Pagurus longicarpus
• www.nwf.org — authoritative profile of Pagurus longicarpus
• iNaturalist · taxon 51416
• IUCN Red List — search for Pagurus longicarpus
• GBIF occurrence records
• Encyclopedia of Life — Pagurus longicarpus

§ Sources cited

• Smithsonian Marine Station Fort Pierce
• Mote Marine Laboratory
• iNaturalist