THE ANIMAL FILES

Orange clownfish

Amphiprion percula

The largest fish in the group is the breeding female.

Orange clownfish live with host anemones in small groups. A size hierarchy controls reproductive roles, and a male can change sex when the breeding female disappears. Their orange bodies and three pale bars also resemble another clownfish species.[2]

Follow the evidence ↓
Orange clownfish
Image: CrisisRose · Commons · CC BY-SA 3.0
The size hierarchy
The female is the largest group member.[2]
Preparing an egg site
A cleaned surface lies close to the anemone.[2]
Identifying the orange fish
Three pale bars have dark margins.[2][1]

The size hierarchy

A functional breeding pair shares an anemone with smaller non-breeders. When the female dies, the largest male can become female and the largest non-breeder becomes the breeding male. The sequence concerns social position as well as sexual development.[2]

Preparing an egg site

Before spawning, the male selects a nearby site and clears algae and debris, sometimes with help from the female. Eggs are placed on that surface. The anemone is shelter, while the adjacent cleaned substrate is the egg-deposition site.[2]

Identifying the orange fish

Three white bars often bulge forwards and have broad dark margins. That pattern helps describe the fish, but similar orange-and-white markings also occur in other anemonefish, so colour alone can leave identification uncertain.[2][1]

A COMMON MIX-UP

Does every group member breed at the same time?

No. The group contains a breeding pair and smaller non-breeders.[2]

TRY A LITTLE REASONING

Why can loss of one fish change more than the number of residents?

Reveal the explanation

Loss of the dominant female can trigger a change of sex and reproductive roles within the hierarchy.[2]

Sources & editorial notes

Original explanations, checked against the sources below. The image has its own credit and licence above.

  1. NCBI Taxonomy — Amphiprion percula
  2. Fishes of Australia, Museums Victoria — Amphiprion percula

Last fact check:

One discovery leads to another

GuppyColour can attract a mate and catch a predator’s eye.Poecilia reticulata ↗Flathead grey mulletA fish can use river water and still return to sea to spawn.Mugil cephalus ↗Allmouth goosefishThe fishing rod is part of the fish.Lophius piscatorius ↗