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Blue Triggerfish (juvenile)

Pseudobalistes fuscus


This triggerfish, as a juvenile, is identified by its thick ripples of bluish lines across its yellowish brown body. Adults have finer lines and their fins have yellow margins. Adult blue triggerfish are known to mate for life. Females are very aggressive when guarding their nests, and have been known to bite divers. They are highly territorial. This species feeds on sea urchins, crustaceans, mollusks, dead fish, tunicates, coral, and can grow to a maximum of 55cm in males.


P. fuscus occurs in clear, shallow lagoons and seaward reefs, although sandy areas near reef patches are preferred. Adults are found on deep reefs, usually deeper than 30m, while juveniles inshore on rubble reef or small outcrops on open substrate.


Spotted this brightly-colored juvenile triggerfish in about 15m of water at the Dayang Beach dive site. It appeared to be guarding its feeding area as it was constantly chasing other fish from its patch. Unlike other species of triggerfish, this one didn't seem to be very skittish -- still, I maintained a good distance because it looked rather aggressive.

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patty 8 years ago

Cool picture Blogie! Looking at Ron´s diving picture made me wonder where you were, hope you are diving and enjoying nature a lot; we miss the awsome pictures. Greetings =)

Blogie 8 years ago

Gracias, Maria! :)

Maria dB
Maria dB 8 years ago

Great spotting and the video is wonderful showing its behavior!

Spotted by

Davao Del Norte, Philippines

Spotted on Dec 8, 2012
Submitted on Dec 9, 2012

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