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Billfish

Xiphiidae | Istiophoridae

Billfish are large, fast pelagic predatory fishes defined by an elongated upper jaw (a “bill” or rostrum). The group typically includes marlins, sailfishes, and spearfishes (family Istiophoridae) plus the swordfish (family Xiphiidae). Billfishes are primarily inhabitants of warm seas, often in the upper water layers above the thermocline, but they can follow prey into temperate waters and undertake long (sometimes transoceanic) migrations. Their bill is used in feeding to slash, stun or injure prey.

Billfish are large, fast pelagic predatory fishes defined by an elongated upper jaw (a “bill” or rostrum). The group typically includes marlins, sailfishes, and spearfishes (family Istiophoridae) plus the swordfish (family Xiphiidae). Billfishes are primarily inhabitants of warm seas, often in the upper water layers above the thermocline, but they can follow prey into temperate waters and undertake long (sometimes transoceanic) migrations. Their bill is used in feeding to slash, stun or injure prey.