Hermit crabs and sea anemones often work together in a symbiotic relationship to provide each other with survival support in the ocean. The creatures can work together for food and protection, but it's important to take note of the characteristics of the creatures to understand why they can help one another.
Sea anemones often stay in one place in the ocean and attach themselves to a surface using a basal disc. Sea anemones are generally between 5 cm and 17 cm long, are very colorful and have the appearance of ocean flowers. The diet of sea anemones consists of shrimp, plankton, fish, isopods and amphipods. Sea anemones are related to jellyfish and corals.
Hermit crabs protect their bodies with empty seashells. Hermit crabs move to larger shells to accommodate their bodies as they grow larger. Hermit crabs can range in size from 2 cm to 100 cm. Hermit crabs are usually found in groups and usually live in colonies of 100 crabs or more. The diet of hermit crabs consists of what they scavenge from the ocean floor.
Both hermit crabs and sea anemones are ocean creatures, but the creatures have different biological classifications. Hermit crabs are members of the Crustacea subphylum and the Malacostraca class; sea anemones are part of the Cnidaria phylum and the Anthozoa class. Hermit crabs live inside and move between shells; sea anemones use an adhesive "foot" to attach themselves to surfaces on the ocean floor, as well as to hermit crabs.
Since sea anemones sometimes attach themselves to the shell of hermit crabs, sea anemones can then eat the food particles that are left floating when a hermit crab eats. Hermit crabs can benefit from the sea anemones that attach themselves to the shell of hermit crabs and can sting predators that put the hermit crabs in danger.