Marine life identification guide>Surgeonfish & unicornfish

Surgeonfish & unicornfish species identification guide


A peaceful herbivorous fish, hiding a redoubtable scalpel-like spine

Acanthuridae (a family comprising surgeonfish -or tangs- and unicornfish) have in common a scalpel-like thin sharp blades located at the base of their tail. In case of danger, they draw those blades and use their tail to defend themselves. Though middle-sized (15 to 40 cm at most), they are some of the most colorful reef fish. They mostly feed on algae and play a crucial part in the reef ecosystem as they leave room for coral to grow. Surgeonfish can be observed alone, in small groups and even in impressive schools of hundreds of fish.

Where are surgeonfish found?

The most famous surgeonfish undoubtedly is the blue tang (or palette surgeonfish). Kids and grown-ups know it as Dory, unforgettable yet forgetful sidekick in Pixar’s “Finding Nemo”. The best places to spot palette surgeonfish while snorkeling are the Western Indian Ocean (Zanzibar Island, Coromos, Madagascar and Seychelles) and the Great Barrier Reef. You’re most likely to spot the convict surgeonfish with its black vertical stripes, very common from Eastern Africa to the Pacific area. In Hawaii, the yellow tang is unmissable, while the razor surgeonfish can be easily spotted in the eastern Pacific, including the Galápagos Islands. Only 3 surgeonfish species live in the Caribbean, including the Atlantic blue tang that can be seen in most spots.

Caribbean & Western Atlantic surgeonfish

Indian & Pacific Oceans surgeonfish

Eastern Pacific Ocean surgeonfish

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