By Jacob Buckholz
The fish that can “fly” through the air for long distances is called the flying fish. It takes to the air with two winglike fins that are attached to either side of its body. These are known as pectoral fins. They are really elastic membranes that, when spread, serve as “wings.”
The flying fish does not fly for pleasure. Usually it leaves the water only when it is pursued by its enemies. Chief among the ocean creatures who prey on it are sharks, tuna, porpoises, and dolphin
To escape its pursuers, the flying fish first increases its swimming speed. Its two pectoral fins are kept folded against its body. When it is swimming fast enough, it swoops up out of the water. Sharp blows of its tail on the water’s surface give added power to its take-off, at which time it often attains a speed of 35 miles (56 kilometers) an hour. As it takes off it spreads its fins and soars out of its enemies’ reach. The flying fish can stay aloft from 2 to 15 seconds. In the air it can span from 45 to 200 yards (41 to 183 meters).
The flying fish is found only in warm-water or tropical seas. It is deep blue on its back and sides and silvery underneath. Some 65 species are known. Depending upon species, body lengths range from 2 to 18 inches (5 to 46 centimeters). The most common species is called Exocoetus volitans. It is found in the warm waters of the Atlantic Ocean. A larger species is found off California. It is called Cypselurus californicus.
Flying Fish, any of a family of marine fishes that have well-developed pectoral fins and are known for their ability to "fly." They are inhabitants of the surface of the open seas of the tropics and are most common far from land. Flying fish are considered excellent eating and are commercially important in many places.
Flying fish have torpedo-shaped bodies. Their maximum length is about 11/2 feet (45 cm). The lower lobe of the caudal fin is longer than the upper. All the fins are spineless and soft-rayed. In some flying fish, known as biplane flying fish, the pelvic fins as well as the pectoral fins are enlarged; in others, known as monoplane flying fish, the pelvic fins are relatively small.
Flying fish do not fly in the normal sense of the term. Their pectoral fins, which correspond to birds' wings, are held rigid against air currents and are gliding rather than propulsive structures.
A monoplane flying fish gains momentum under water by rapidly beating its caudal fin until it shoots up out of the water. Then the fish extends its pectoral fins rigidly to act as gliding wings. The flight tends to be erratic and is greatly influenced by air currents. It rarely lasts for more than about 5 to 8 seconds.
The flight of biplane flying fish is more complex. The biplane fish builds up momentum under water in the same way as the monoplane flying fish does, but upon breaking into the air it usually remains near the surface with its pectoral fins extended and the enlarged lower caudal fin lobe in the water. With this caudal lobe it makes rapid sculling motions to propel itself along the surface, increasing its speed until it rises into the air by extending its enlarged pelvic fins.
The flight of the biplane fish may be a single glide of up to 13 seconds' duration, but very often it is a composite flight in which the first glide ends with the caudal lobe once again entering the water to beat in sculling motions until momentum is gained for the beginning of the next glide. One such composite flight involving several such touchdowns was clocked at 42 seconds. Most flights are within about 5 feet (1.5 meters) of the surface, but some fish may soar up to about 35 feet (10.5 meters) from the surface. Composite flights of as long as 1,000 feet (300 meters) have been recorded, but 200 to 300 feet (60–90 meters) is a normal flight length.
About 50 species of flying fish make up the family Exocetidae. Together with needlefish and halfbeaks, they are classified in the order Atheriniformes.