Photograph by Scott Tuason

Barracudas, family Sphyraenidae, all belong to one genus - Sphyraena. These streamlined fish have a projecting lower jaw with several large, sharp-edged teeth and an elongate body with two widely separated dorsal fins. Barracuda are predatory fish that patrol sunlit, open waters, relying on sharp eyesight and great speed to catch its prey. When a school of fish comes within striking range, the barracuda passes through it in a single rush, slashing and tearing with knife-like teeth. Then the barracuda returns at leisure to feed on the fragments.

Barracuda are highly adapted to their open ocean habitat - as they hover motionless near the surface their presence is made less conspicuous by a type of camouflage known as obliterative shading. Seen from above the barracuda's grey-green, slightly dappled back matches the tone and texture of the water; from below, its silvery belly blends equally well with the brightly lit surface water. Virtually all fish that spend much time in open water have this dark-above, light-below shading.

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