Which fish has a long, sword-like bill?

Which fish has a long, sword-like bill? The answer is swordfish. Its bill is a distinctive, flattened extension of the upper jaw that gives the species its common name and separates it from other billfish such as marlin and sailfish.

The swordfish (Xiphias gladius) is the only living member of the family Xiphiidae. It is a powerful, highly migratory predator found in tropical and temperate waters of the Atlantic, Pacific, and Indian oceans. The bill is used mainly to slash through schools of fish and stun prey rather than to spear them.

Swordfish can grow to about 4.5 metres and weigh more than 600 kilograms, although most are smaller. Adults lose their teeth and scales, an unusual transformation among fish. They also have specialised muscles that warm their eyes and brain, helping them see in cold, deep water.

Marlin and sailfish also have long bills, which is the common mix-up. Their bills are generally rounder and more spear-like, while the swordfish’s bill is notably broad, flat, smooth, and sword-shaped.