The sailfish is a type of fish that is found across much of the world's temperate and tropical oceans. There are two species of the fish, the Indo-Pacific sailfish and the Atlantic sailfish, although two two are extremely similar in size, behavior and appearance. Both fish are of the Istiophorus genus, which is part of the Istiophoridae family of fish.
This is a very large fish. The Indo-Pacific sailfish will commonly grow to approximately 9 feet (2.7 meters) in length and weigh more than 220 pounds (100 kg). The smaller Atlantic variety is still very large, and usually grows to about 8 feet (2.4 meters) in length and weighs upwards of 132 pounds (60 kg). Both share common physical and behavioral characteristics.
The most notable physical characteristics of the sailfish is its long bill that resembles that of a swordfish, and the feature that is is named after; its large dorsal fin which resembles a sail. The fin stretches across the back of the fish, although it is usually kept folded to the side. When the fish is either excited or in danger the fin will become erect. This defensive posture makes the fish appear much larger than it actually is.
The sail also serves another purpose when the fish is hunting. Sailfish primarily eat smaller fish and squid, and the sail can be used to help "herd" large groups of small prey into compact schools or packs, making it easier for the sailfish, which usually hunt in groups, to pick off the fish one by one. The two species of fish are found in the oceans they are named after, usually in any area with temperate to tropical climates. Both species prefer to swim and hunt in the upper depths, but they h ave been spotted as deep as 220 yards (200 meters). There appears to be some overlap between the species' habitat, so much so that some scientists consider them to be a singular species. This point has not been agreed on by many who study the animal.
The sailfish is an extremely popular commercial and game fish. Sport fishermen consider sailfish to be one of the most difficult fish to successfully catch, thanks to its incredible power and speed. When leaping the speed of the fish has been measured at 68 mph (110 kph). Commercial fisheries often sell the fish fresh and is is usually prepared smoked, broiled or baked. Sashimi and sushi restaurants also often serve the fish raw.