Clownfish

There are about 300 species of clownfish or damselfish. They live in the western and central Pacific Ocean among the coral reefs, and are especially common in the Australian Great Barrier Reef.

Clownfish are very unique because they are the only fish that can live among the deadly, stinging tentacles of the sea anemone without being killed. A coating of mucus covers the clownfish’s body. This mucus is exchanged between the anemone’s tentacles and the clownfish’s body, resulting in complete protection for the fish.

Although anemones can exist quite happily without their clownfish, it appears that as well as acting as cleaners, these little fish also help, through their fiercely territorial behavior, to protect their host from would-be predators (such as the butterfly fish).

The clownfish actually lures other fish into the anemone and then feeds on the remains. In addition, the clownfish feeds on plankton, algae, and debris from the dead tentacles of its host anemone.

Clownfish live in family groups led by an adult female, which mates with a male from another group. She lays her eggs in batches on a rock near the anemone. The male will guard the eggs, which hatch in four to five days. Sometimes the male will even care for the young until they reach maturity. At that time, they will find their own sea anemone.

Clownfish have both male and female sex organs. When the dominant female dies or is eaten, the dominant male changes into a breeding female to replace her. A juvenile replaces the dominant male.

Clownfish are too small to be hunted for food but are very popular for saltwater aquariums. There is now a restriction on the number of clownfish that can be taken for this purpose.