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The Interesting Hermit Crab and Sea Anemone Relationship

The Interesting Hermit Crab and Sea Anemone Relationship

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This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addition, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Hermit crabs are such interesting creatures. They’re truly fascinating once you start to observe them.

There are different types of hermit crabs that you might want to keep at home. Land hermit crabs are commonly kept as pets, but marine hermit crabs are also fairly commonly kept in home aquariums.

You can keep marine hermit crabs with certain types of fish. Of course, you need to ensure that the fish have the same water parameter requirements as the hermit crabs.

What about sea anemones? Can you keep sea anemones in the same tank as hermit crabs?

Keep reading to learn about the relationship between sea anemones and hermit crabs. This will ensure that you understand what you can do in the tank.

Hermit Crabs and Sea Anemones Have Symbiotic Relationships

The relationship between hermit crabs and sea anemones is rather interesting. You see, hermit crabs and sea anemones have a symbiotic relationship.

It’s common for hermit crabs to carry sea anemones around with them. The sea anemones attach themselves to the shells of the hermit crabs.

The two have an interesting relationship that stands out from other symbiotic relationships that you might be familiar with. The two creatures get along well and help each other out.

They have a relationship that is known as “commensalism.” This is a term that describes a relationship where one creature benefits while the other isn’t harmed in any way.

Below, you’ll learn a bit more about how sea anemones and hermit crabs work together. It’s very interesting and it might make you want to see the relationship in action for yourself.

Hermit Crabs Are Protected By Sea Anemones

Hermit crabs gain protection by having sea anemones attached to their shells. The hermit crabs are somehow able to communicate with the sea anemones to alert them to threats.

At this time, researchers aren’t sure how they communicate with the anemones. It’s believed that hermit crabs use either a chemical method of communication or a mechanical communication method.

Either way, it’s noted that sea anemones respond to protect the hermit crab. Sea anemones possess long stinging tentacles that can kill many types of predators.

A hermit crab that has a symbiotic relationship with a sea anemone is going to be much safer than one that is by itself. Predatory fish that might want to eat the hermit crab will be taken out easily by the sea anemone.

Seeing a sea anemone protect a hermit crab is rather interesting. It makes total sense why hermit crabs would want to have sea anemones onboard.

The Sea Anemone Gets Food for Its Troubles

So what’s the benefit for the sea anemone? Well, it gets food for protecting the hermit crab.

Sea anemones aren’t picky eaters and they will consume pretty much anything that they can in the sea. They will feed off of bits of food that are left behind by the hermit crab.

The hermit crab will find food and the sea anemone will also get a meal. This winds up working out nicely for the sea anemone.

Sea anemones get a reliable food source by attaching themselves to hermit crabs. It keeps them fed and that’s enough to make the relationship worthwhile.

Of course, there might be other benefits that haven’t been discussed yet. There’s another big reason why sea anemones like to hitch a ride on hermit crabs’ shells.

It Also Helps Sea Anemone to Get Around Better

You may or may not know that sea anemones have limited mobility. They don’t move around a lot.

Their lack of mobility makes it tougher for them to get around and find food. By attaching to a hermit crab’s shell, the sea anemone is going to get around a lot better.

The hermit crab will carry the sea anemone to many different places. It’ll give it a chance to eat more often and it’s generally very beneficial to the sea anemone.

Without the help of the hermit crab, a sea anemone would have a very limited area where it would explore. The symbiotic relationship with the hermit crab allows it to travel the sea floor.

The sea anemone can kill and consume many things while riding on the back of a hermit crab. It’ll kill and eat plankton as well as various types of small fish.

Will They Ever Kill Each Other?

It’s very unlikely that a sea anemone and a hermit crab will kill each other. However, there could come a time when a hermit crab will get desperate.

If a hermit crab is unable to find food, it might choose to eat the sea anemone on its shell. This doesn’t happen often because hermit crabs benefit quite a bit from keeping the sea anemones around.

A hermit crab would often prefer to keep its sea anemone above all else. Even so, there have been instances where hermit crabs have eaten sea anemones.

There could be a situation where a hermit crab might try to eat a sea anemone that is present on the shell of another crab. It’s not very common, though.

Generally, this isn’t something that you need to worry about. It’s just interesting to know that it happens.

Can You Keep Hermit Crabs and Anemones in the Same Tank?

Yes, you can keep hermit crabs in a fish tank with sea anemones. However, you need to pick the right type of marine hermit crab and the right type of anemone.

Take some time to pick compatible anemones and marine hermit crabs. Ensure that you give them the ideal tank situation.

Many enthusiasts have kept hermit crabs and anemones in the same tanks for years without issues. Be sure to follow the care requirements of each and everything should go okay.

It might be interesting to be able to see these creatures interact in your home tank. Just as many people are interested in seeing the symbiotic relationship between clownfish and anemones, people are also keen to see hermit crabs and sea anemones.

Final Thoughts

You should feel like you know a lot more about hermit crabs and sea anemones now. These creatures form symbiotic relationships in the wild.

They help each other out in various ways. Hermit crabs gain significant protection from having sea anemones on their shells.

The sea anemones will sting predators that try to attack the hermit crabs. Anemones are excellent protectors that will keep hermit crabs safe from many threats.

Hermit crabs help sea anemones to get around better. Under normal circumstances, the mobility of sea anemones is limited.

They can only cover small areas due to not being able to get around well. Hermit crabs change this for them and allow them to get around and hunt for food by hitching a ride.

The sea anemones will also eat leftover food when hermit crabs are finished eating. It gives them access to an easy meal.

If you want to, it’s possible to keep marine hermit crabs and anemones in the same tank. Just pick the right kinds of marine hermit crabs and anemones so you’ll get good results.

Now that you know everything that you need to know about this topic, you can decide how to proceed. You can find marine hermit crabs and anemones being sold at local pet stores.

It’s also very easy to get what you need online. Take care of your aquarium well and be sure to watch the water parameters.

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