The orange clownfish (Amphiprion percula) also known as percula clownfish and clown anemonefish, is widely known as a popular aquarium fish. Although popular, keeping this species in captivity is quite complex. Like other clownfishes, it often lives in association with sea anemones. The fish feed on algae, zooplankton, worms, and small crustaceans.
The symbiosis between orange clownfish and anemones depends on the presence of the fish drawing other fish to the anemone, where they are stung by its tentacles. The anemone helps the fish by giving it protection from predators, which include brittle stars, wrasses, and other damselfish, and the fish helps the anemone by feeding it.
Various hypotheses exist about the fish’s ability to live within the anemone without being harmed. One study carried out at Marineland of the Pacific by Dr. Demorest Davenport and Dr. Kenneth Noris in 1958 revealed that the mucus secreted by the orange clownfish prevented the anemone from discharging its lethal stinging nematocysts. A second hypothesis is that the orange clownfish has acquired immunity towards the sea anemone, and a combination of the two has been shown to be the case.