Coral Reef Fishes

IJsselstein, Wednesday, 6 June 2001 04:37:14

Corals are a true treasure-chest of colorful tropical fish. When snorkling or diving, you will be overwhelmed by the sheer numbers and varieties you will encouter, but what types are you actually seeing?


Anemonefishes can hardly be mistaken. Most types of anemonefishes are characterised by an orange, red, or black background, with one to three vertical white stripes, and are always found near a host anemone. When threatened, it will seek refuge in its tentacles, which are posionous to most other fishes, but curiously do not harm the anemonefish. This is achieved by a special chemical substance, secreted by the fish' skin mucus, which prevents the stinging cells from firing. Although harmless, their behavour is often quite couragous. In spite of their small size, about 10 to 15 centimeters tall, they will make feigned attacks on divers much larger than themselves.

Anemonefishes can be found on about ten different species of sea anemones. Most have a preference for four or five species of anemones, and some are only found on one specific species, but only the clark's anemonefish is not able to tolerate all types of anemones.

The eggs of the anemone fish are deposited near the foot of their host anemone, well protected by its tentacles. Still, the male will vigorously protect the eggs, until they hatch after six or seven days. For one or two weeks, the larvae will swim freely, after which they will find a host anemone.

Anemonefishes can be found all over the Indo-pacific region, from as far west as the coast of East Africa up to Polynesia in the east.

Jeroen Hellingman