High Quality Content by WIKIPEDIA articles! Sailfish are two species of fish in the genus Istiophorus, living in warmer sections of all the oceans of the world. They are blue to grey in color and have a characteristic erectile dorsal fin known as a sail, which often stretches the entire length of the back. Another notable characteristic is the elongated bill, resembling that of the swordfish and other marlins. They are therefore described as billfish in sport fishing circles.Both species of sailfish grow quickly, reaching 1.2-1.5 m (4-5 ft) in length in a single year, and feed on the surface or at mid-depths on smaller pelagic forage fish and squid. Individuals have been clocked at speeds of up to 110 km/h (70 mph), which is the highest speed reliably reported in a fish. Generally, sailfish do not grow to more than 3 m (10 ft) in length and rarely weigh over 90 kg (200 lb).