Photographer: Paul Osmond
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A very large Titan Triggerfish (Balistoides viridescens), at about 2 1/2 feet, guards it territory and nest. These fish have a reputation as being very terratorial and many scuba divers have been nipped and bitten by this fish, often breaking skin.
This image was taken on the coral reef that surrounds Raine Island in far north Queensland, Australia. Raine Island is famous for the presence of a huge nesting population of Green Turtles, but also is home to a variety of other marine species.