Family variety
A large family with over 300 species, most Damselfish are small have a broadly similar body shape. There is lots of variety in their patterns and markings, with yellow, black, white and blue being the most common colours.
Size
The Lined Chromis (chromis lineate) is the smallest member of the Damselfish family at around 5cm, while the largest found in Asian Pacific waters is the Indo-pacific Sergeant Major (Abudefduf vaigiensis) at up to 19cm.
Behaviour
Damselfish often live in groups on the reef, either drifting above the water column feeding on passing plankton, or on the reef itself feeding on algae growing on the coral.
Despite their small size they can be very aggressive when protecting feeding territory or their nests. They are not scared of attacking much larger fish or even unsuspecting divers.
Distribution
Found in all tropical and some temperate waters worldwide.
Habitat
Most species are reef dwelling, living in or very close to the shelter that the reef provides for small fish. Anemonefish live their whole lives within the protection of a sea anemoneís stinging tentacles, to which they have developed an immunity.
Diet
Damselfish can be either plankton feeding, filtering passing microscopic life from the water column, or feed on the the reef itself, nibbling on the layer of algae that coats the reef.
Reproduction
Damselfish lay eggs in patches on the reef which are then protected by the breeding couple until they hatch. In some areas where species breed in unison, the reef can turn purple from the patches of purple eggs everywhere.
Defences
Damselfish are generally shy, quickly retreating to the safety of the reef if they feel threatened. Some species however defend their feeding territory with fierce aggression. Anemonefish use their hostís poisonous tentacles to deter would be predators. The fish themselves are coated in special mucus that protects them against the anemoneís deadly sting.
Threats
Damselfish are not fished as eating fish, a few species are targeted by the aquarium trade but their largest threat is the destruction of their habitat with the decline of coral reefs.
Did You Know?
Anemonefish are also known as clownfish, and are one of the most well known tropical reef fish thanks to the movie Finding Nemo!
Intro
Everybody has heard of Nemo, but not many know that this species is a member of the Damselfish family - a large family that includes many of the smaller fish that make up the numbers on Asia's reefs.
Damselfish are one of the most successful tropical fish families. As well as Anemonefish, the family also includes Sergeant Majors, Humbugs, Fork-tailed Chromis and many other commonly encountered species.
Popular species 1
Western Clownfish
(Amphiprion ocellaris)
Made famous as the star of 'Finding Nemo', these little orange and white fish spend their time dancing among the tentacles of their host anemone.
Popular species 2
Sergeant Major
(Abudefduf vaigiensis)
Often found in large numbers on reefs throughout the region, they school in open shallow water well above the reef, filtering the water for tasty plankton.
Popular species 3
Clark's Anemonefish
(Amphiprion clarkii)
One of the larger anemonefish species, can be very aggressive for their size. They show little fear of larger fish or divers and will protect their territory courageously.
Popular species
Look out for these species of damselfish on your next dive.
FACTFILE
SPECIES: >300
SIZE RANGE: 5-19 cm
DISTRIBUTION:
Found in all tropical and some temperate waters worldwide.
HABITAT:
Reef dwelling. Anemonefish live their whole lives within the protection of their host anemone.
THREATS:
Destruction of habitat.
Identification tips
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Damselfish are generally small fish, growing to no more than 20cm long
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Single continuous dorsal fin.
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Forked, lunate or rounded tails, depending on species.
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Often large, very visible scales in relation to body size..
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Most common colourations within this large family are black, white, yellow and blue.
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Characterised by large prominent mouths.
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Thin flattened bodies with a round or oval side view.
