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Explorer's Guide
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The Explorer's Guide contains a treasure trove of aquatic science resources developed for use in K-12 classrooms. Back to Explorer's Guide.

Anemone Clownfish Scientific Name: Amphiprion ocellaris
Anemone clownfish make their home inside the dangerous stinging tentacles of anemones. Newborn fish cover themselves with an anemone’s slimy mucus coating. This protects the clownfish against the anemone’s deadly sting, which paralyzes most other small fish.

Region: Philippines

With bright colors like a clown, this fish is orange with three white bars across its body. The anemone clownfish is only up to 4 inches (11 cm) long, but can be a potential threat to predators or even divers looking to collect them. The bright coloring is warning coloration and lets predators know that they will be harmed if they try to eat it. The anemone clownfish carries stinging cells on its skin.

Certain reef creatures form partnerships with other kinds of animals or plants. Partners feed, house or protect one another. Each partner needs the other in order to survive. These relationships are called symbiotic relationships.

Anemone clownfish get their name from their colorful skin, like that of a clown, and from the anemone in which it lives. Anemone clownfish are obligatory symbionts, meaning they probably can’t live without their anemone host. This fish snuggles among the deadly stinging tentacles of an anemone. All anemones have nematocysts or stinging cells in their skin. Most fish avoid anemones, but anemones provide clownfish with a safe haven. In return, the clownfish cleans the anemones, chasing away their predators and dropping scraps of food for the anemone to eat.

Together the anemone and clownfish live in shallow and calm lagoons or coastal reefs to depths of 50 feet (15m). There are only four different kinds of anemones with which this fish will live.

Anemone clownfish have special skin protection that allows them to nestle into the dangerous anemones. When young clownfish settles out of the plankton they search for an anemone to live in. The fish slowly begins to adapt to living in a stinging anemone by making quick contacts with its tentacles. Most sea creatures have a protective mucus or slime coating. The clownfish begins mixing the slime of the anemone, which has stinging cells, with its own skin slime. Every day the fish stays longer and longer among the anemone’s tentacles until all of its slime is completely mixed with the anemone’s. This protects the anemone clownfish from getting stung.

These fish live alone, in pairs, or even in a small group within one anemone. Sticking close to their anemone host, these clownfish rarely move far away.

The sea anemone benefits from this relationship too. Clownfish chase away any other fish, like butterflyfish, that try to eat their anemone. They also clean their anemone, removing parasites and dead skin.

Anemone clownfish live in the warm parts of the Pacific Ocean and Indian Ocean.

Picking zooplankton or tiny animals, phytoplankton or tiny plants, and bits of algae from out of the water, anemone clownfish feed as the current flows past. Anemone clownfish only eat things they can swallow whole.

Anemone clownfish are protandrous hermaphrodites, which means they can start their life as a male and then change to female. These fish are born with both male and female sex organs. Usually a group of anemone clownfish lives in the same anemone or there are a few anemones close together where a group of these fish live. The largest fish in the group is a female and the second biggest is a male. All the other clownfish are neuter, which means they have not fully developed functioning sex organs for either gender. If the female should die, the male will change sex, while the biggest neuter clownfish will develop functioning male sex organs to replace the male.

The eggs of anemone clownfish are a deep reddish orange. Clownfish lay their eggs at the base of their host anemone. To protect the eggs from predators, the clownfish rubs the anemone, getting it to fully open up and cover the eggs with its tentacles.

>A species or group of organisms that is in danger of extinction or disappearing from the face of the earth in the near future if its situation is not improved.

A species that can be found throughout its natural range but is declining in number and may become endangered in the absence of special protection efforts.

A species that is not declining in number but is of special concern because it is sensitive to pressure by particular human activities or natural events.

A species that is not declining in number and is not sensitive to pressures by human activities or natural events.

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Threats and Management
Anemone clownfish are one of the most popular fish in the pet trade. Many home aquarium hobbyists keep these fish. They typically do well, but need a host anemone as well. Purchasing this pair can be quite expensive. The population of anemone clownfish is stable, but over collection of them could threaten these animals.

Did you know?
Anemone clownfish can be quite ferocious. They protect their host anemone so fiercely that they will even chase away and bite at divers which are hundreds of times larger than themselves.

Web Sites:
NOTE: The following Web sites are not maintained by the John G. Shedd Aquarium and will open in a new browser window.


Print Publications:
Cousteau, J.Y. 1979. The Ocean World. New York: Abradale Press / Harry N. Abrams, Inc. 446 p. ISBN# 0-8109-8068-1.

Debelius, H. 1999. Indian Ocean Reef Guide. Frankfurt, Germany: IKAN. 321p.
ISBN# 3-9317-0267-7.

Fautin, D.G. and Allen, G.R. 1992. Anemone Fishes: And Their Host Sea Anemones. Australia: Western Australian Museum. 160p. ISBN# 0-7309-5216-9.

Hoover, J.P. 1993. Hawaii’s Fishes. A Guide for Snorkelers, Divers and Aquarists. Honolulu, Hawaii: Mutual Publishing. 183p. ISBN# 1-56647-001-3.

Kuiter, R.H. 1998. Photo Guide to Fishes of the Maldives. Australia: Atoll Editions. 257p. ISBN# 1-876410-18-3.

Myers, R.F. 1999. Micronesian Reef Fishes. Barrigada, Guam: Coral Graphics. 216p.
ISBN# 0-9621564-4-2.

Perrine, D. 1997. Mysteries of the Sea. Lincolnwood, Illinois: Publications International, Ltd. 312p. ISBN# 0-7853-2430-5.

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Vocabulary Words

Extinction – An organism that has not been present on the face of the earth for over 50 years.

Hermaphrodite – Having the sexual organs of both male and female; able to produce both egg and sperm.

Nematocyst – Stinging cells that release tiny harpoon-like stingers which deliver a paralyzing poison sting to stun or kill prey.

Neuter – Being neither male or female.

Obligatory symbionts – Animals that must live with another animal.

Organism – A living thing.

Pet trade – An industry or business in which animals are taken from the wild and sold to pet stores, zoos, and aquariums.

Phytoplankton – Microscopic plants that float at the mercy of the ocean currents.

Protandrous – Starting life as a male then changing into a female.

Species – A group of organisms capable of breeding and producing fertile offspring; organisms that share the same gene pool.

Symbiotic relationship – Symbiosis – In order to survive, certain creatures form partnerships with other kinds of animals or plants for feeding, housing or protecting one another.

Warning coloration – Bright colors or wild patterns warning other animals of the colorful animal’s poisonous or venomous nature.

Zooplankton – Microscopic animals that float at the mercy of the ocean currents and have weak swimming ability.

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Anemone Clownfish
Anemone Clownfish

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