Six Fascinating Symbiotic Relationships Among Marine Animals

Symbiosis, a phenomenon that occurs in nature, is when two unlikely animals have close physical interaction with one another. There are three types of symbiotic relationships.

  • Mutualism – When both animals benefit from the interaction.
  • Commensalism – When one animals benefits and the other animal neither benefits or is harmed by the interaction.
  • Parasitism – When one animal benefits from the interaction and the other animal is negatively affected by the intereaction.

In the ocean, one of the most famous symbiotic relationships occur between clownfish and sea anemones. This relationship was made popular by the Pixar film Finding Nemo.

Here are six other symbiotic relationships that occur among marine animals:

1. Boxer Crabs and Anemones

The boxer crab carries around two sea anemones on its claws. The anemones help the crab fight off other animals with stinging cells along their tentacles. In return, the anemone feeds on scraps from meals eaten by the crab. This relationship is an example of mutualism.

Boxer Crab and Sea Anemone © Prilfish / CC-BY-2.0

2. Feather Stars and Crinoid Shrimp

In this relationship, the crinoid shrimp receives shelter, protection and feeds off the star’s waste. It is often hard to find the crinoid shrimp on the feather star / crinoid. This is because the shrimp camouflages and adopts the markings and colors of the feather star. This relationship is an example of commensalism.

Crinoid Shrimp on Feather Star © Bernard Dupont / CC-BY-S.A. 2.0

3. Manta Ray and Remora (sucker fish)

In this relationship, the manta ray is cleansed of parasites along it body by the remora. Remoras feed on the parasites found on the manta ray. This is a mutual relationship.

Manta Ray swims with remora fish in Western Australia © Brocken Inaglory / CC-BY-S.A. 3.0

4. Sea Cucumber and Emperor Shrimp

The emperor shrimp seeks out shelter and protection on large, slow moving animals such as the sea cucumber. They also receive scraps from whatever its host eats. This is a commensal relationship.

Close up of Emperor Shrimp on the back of a Sea Cucumbers © Elias Levy / CC-BY- 2.0

5. Moray Eels and Cleaner Shrimp

Cleaner shrimp get their names because they clean parasites off of large animals such as eels. In this relationship, the eel is being relieved of parasites while the shrimp is being fed. This a mutual relationship.

Cleaner shrimp cleaning the mouth of a moray eel © Steve Childs / CC-BY- 2.0

6. Swimming Crab and Barnacle

Barnacles sometimes grow on the reproductive organ of the swimming crab. This prevents the crab from reproducing. This is an example of a parasitic relationship.

Parasitic barnacle on female swimming crab © Hans Hillewaert / CC-BY-S.A 4.0

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s