Clown fish in the Andaman Coral Reef.
Clownfish or anemonefish are fishes from the subfamily Amphiprioninae in the family Pomacentridae. Thirty species are recognized: one in the genus Premnas, while the remaining are in the genus Amphiprion. In the wild, they all form symbiotic mutualisms with sea anemones. Depending on species, anemonefish are overall yellow, orange, or a reddish or blackish color, and many show white bars or patches. The largest can reach a length of 18 centimetres (7.1 in), while the smallest barely achieve 10 centimetres (3.9 in).
Bright orange with three distinctive white bars, clown anemonefish are among the most recognizable of all reef-dwellers. They reach about 4.3 inches (11 centimeters) in length, and are named for the multicolored sea anemone in which they make their homes.
Distribution and Habitat[]
Anemonefish are native to warmer waters of the Indian and Pacific oceans, including the Great Barrier Reef and the Red Sea. While most species have restricted distributions, others are widespread. Anemonefish live at the bottom of shallow seas in sheltered reefs or in shallow lagoons. There are no anemonefish in the Atlantic.
Diet[]
Anemonefish are omnivorous and can feed on undigested food from their host anemones, and the fecal matter from the anemonefish provides nutrients to the sea anemone. Anemonefish primarily feed on small zooplankton from the water column, such as copepods and tunicate larvae, with a small portion of their diet coming from algae, with the exception of Amphiprion perideraion, which primarily feeds on algae. They may also consume the tentacles of their host anemone.
Gender and Mating[]
Clownfish perform an elaborate dance with an anemone before taking up residence, gently touching its tentacles with different parts of their bodies until they are acclimated to their host. A layer of mucus on the clownfish's skin makes it immune to the fish-eating anemone's lethal sting. In exchange for safety from predators and food scraps, the clownfish drives off intruders and preens its host, removing parasites.
There are 28 known species of anemonefish, most of which live in the shallow waters of the Indian Ocean, the Red Sea, and the western Pacific. They are not found in the Caribbean, Mediterranean, or Atlantic Ocean. Surprisingly, all clownfish are born male. They have the ability to switch their sex, but will do so only to become the dominant female of a group. The change is irreversible.
