Odd Relationships
Clown Fish \ Anemones

Anemones are flowerlike marine animals with neurotoxin filled stinging tentacles. They use these to help them subdue their prey, which are mostly plankton, crabs and fish, though larger species take larger prey such as starfish and jellyfish.

Anemones associate with many fish species, but they are particularly close with one group. Clownfish, also known as anemonefish, are immune to anemone stings, though scientists aren't exactly sure how. It's thought that the layer of mucus on the fish's body is involved in protecting them. This means clownfish can safely nestle into the anemone's tentacles to hide from predators.

In return, clownfish help the anemone in multiple ways. They keep the anemones free of parasites and provide them with nutrients through their faeces, which may also stimulate the growth-beneficial symbiotic algae within the anemone. Clownfish may also drop food onto the anemone and also drive off anemone-eating intruders that stray too close. It's also thought that the movement of clownfish helps to circulate the water, and in turn helps to oxygenate the anemone. It's possible that the bright colours of clownfish also helps to lure meals of small animals to within reach of the anemone.

Anemones that harbour clownfish appear to have faster growth rates, higher rates of asexual reproduction and lower mortality than those without fish.