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The Special Hermit Crab and Sea Anemone Relationship

The Special Hermit Crab and Sea Anemone Relationship

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The purpose of this blog is to share general information and is written to the author's best knowledge. It is not intended to be used in place of veterinary advice. For health concerns, please seek proper veterinary care. In addition, as an Amazon Associate I earn from qualifying purchases.

Hermit crabs are incredibly interesting for a number of different reasons. These creatures are commonly kept as pets by enthusiasts.

You might have heard something about how hermit crabs and sea anemones have a special relationship. Even if you’ve heard this mentioned in the past, you might not truly know that much about it.

This is very much an intriguing topic that every hermit crab fan should learn about. Read on to get all of the information about hermit crabs and sea anemones that you need to know.

By the time you’ve finished reading this article, you’ll gain an even greater appreciation for hermit crabs. This symbiotic relationship between the two creatures is truly something special.

Hermit Crabs and Sea Anemones Have a Symbiotic Relationship

Hermit crabs and sea anemones have formed symbiotic relationships. These two creatures are able to live in harmony, and hermit crabs help sea anemones in various ways.

The sea anemone also helps the hermit crab out. Both hermit crabs and sea anemones benefit from having this special bond.

More specifically, hermit crabs and sea anemones have a commensal relationship. This means that the relationship is beneficial and that there aren’t negative impacts to consider.

The sea anemone is going to cover the shell of the hermit crab. You’ll find that the sea anemone will cover most of the surface of the hermit crab’s shell.

When the hermit crab outgrows its current shell, it’ll usually take the sea anemone with it to a new shell. This is because the hermit crab understands the beneficial nature of having the sea anemone.

Below, you’re going to learn more about some of the ways that this symbiotic relationship works. It’ll help you to understand why these two creatures have formed symbiotic relationships.

The Sea Anemone Protects the Hermit Crab

One of the easiest benefits to understand involves protection. Hermit crabs have to worry about many different types of predators in the wild.

When a predator threatens the hermit crab, the crab is going to signal the anemone somehow. This triggers the sea anemone to attack the predator by stinging it.

This makes it very hard for predatory fish to eat the hermit crab. Sea anemones can extend their stinging threads to provide protection to the hermit crab.

Researchers aren’t entirely sure how the hermit crab communicates with the sea anemone. It’s speculated that it could be some type of chemical communication, but it could be a mechanical communication method.

Many people find it fascinating that hermit crabs have been able to build this relationship with sea anemones. The sea anemones truly do a great job of protecting the hermit crabs.

Sea anemones have even been able to protect hermit crabs from particularly dangerous predators. For example, the presence of a sea anemone might allow a hermit crab to survive an octopus attack.

The Hermit Crab Helps the Sea Anemone to Stay Fed

The sea anemone is going to benefit from this relationship quite a bit as well. As you might know, sea anemones are not considered to be picky eaters.

They will eat pretty much anything in the sea that will give them nutrients. When they have a symbiotic relationship with hermit crabs, they will eat whatever the hermit crabs leave behind.

Hermit crabs will get something to eat and the sea anemone will wind up cleaning up the scraps. Nothing gets wasted this way.

It makes things easy for the sea anemone because it has a constant supply of food from the hermit crab. It helps out a lot since sea anemones aren’t that mobile.

In the wild, being able to find a situation where meals come easy will be hugely beneficial. It makes sense why sea anemones would find being attached to a hermit crab’s shell to be helpful.

Hermit Crabs Help Sea Anemones with Mobility

As mentioned above, sea anemones aren’t exactly the most mobile creatures. Being attached to a hermit crab’s shell makes the sea anemone much more capable of getting around.

This makes it far simpler for the sea anemone to forage for food. The hermit crab moves around the seafloor looking for food all the time.

As the hermit crab moves, the sea anemone will attempt to trap plankton or small fish that swim by. It winds up working out really well for the anemone.

The hermit crab gets the protection from predators that the sea anemone provides. The sea anemone is capable of getting around better due to hitching a ride on the hermit crab’s shell.

It’s definitely interesting how sea anemones and hermit crabs have formed this relationship. There are clear benefits for both creatures.

The hermit crab extends the reach of the sea anemone so much. It’s going to have a much simpler time finding food and thriving thanks to the hermit crab.

How Big Are Anemone Hermit Crabs?

Anemone hermit crabs are not too big actually. These crabs are going to grow to be about four inches at maturity.

These hermit crabs will usually weigh between 7 and 12 ounces. These little hermit crabs scavenge for food and eat many different types of food.

Often, anemone hermit crabs will eat various types of mollusks. They’ll also eat other invertebrates that they can find in the sea.

Will the Hermit Crab Eat the Sea Anemone?

In some cases, a hermit crab might choose to eat the sea anemone on its shell. It’s suspected that a hermit crab would only do so if it felt desperate.

Sometimes, hermit crabs might try to eat the anemones on the shells of other hermit crabs, too. This won’t always happen, but it certainly can.

Sea anemones don’t try to eat hermit crabs, though. It’s more likely that the hermit crab and the sea anemone will get along and continue to help each other out.

Final Thoughts

Hopefully, learning a bit more about hermit crabs and sea anemones will give you a great appreciation of how special their symbiotic relationship can be. It’s certainly interesting to see how much hermit crabs and sea anemones rely on each other.

The hermit crabs benefit from having sea anemones around quite a bit. It helps the crabs to stay protected from large predators.

Without a sea anemone, a hermit crab would have a much harder time with predatory fish and large threats such as an octopus. Sea anemones can sting predators and keep the hermit crabs safe.

It’s interesting how sea anemones can cover the hermit crabs with protective stingers. This will prevent fish and other threats from being able to easily get to the crab.

Hermit crabs benefit sea anemones by giving them access to a steady stream of food. The sea anemone will eat the leftovers from the hermit crab’s meals.

Also, the hermit crab grants the sea anemone greater mobility. By remaining attached to the hermit crab’s shell, the sea anemone is going to be able to get around.

It’ll have opportunities to trap plankton and small types of fish. If the sea anemone didn’t have the hermit crab to rely on, then it would barely be able to move around at all.

Seeing such a relationship is very beautiful in certain ways. If you’re already a bit of a hermit crab fan, then this knowledge of how they have symbiotic relationships with sea anemones will only make you appreciate them more.

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