Flying Fish

Flying fish belong to the family Exocoetidae in the bony fish order Atheriniformes. They are close relatives of the needlefish, halfbeaks, and sauries. Flying fish are characterized by a low lateral line, soft fins without spines, and a caudal fin with the lower lobe larger than the upper lobe. The lower jaw of the young flying fish has an extended filament longer than the body, which becomes detached as the fish grows.

Flying fish have large pectoral fins almost as long as the body which serve as wings, helping the fish glide through the air when it leaves the water. The pectoral fin expands and stiffens while in the air for a short distance before the fish reenters the water. A flying fish can remain airborne for at least 30 seconds and can reach a top speed of at least 40 MPH (64 km/h) produced by the rapid movement and vibration of the tail. The tail is the first part of the fish to reenter the water, making it possible for the fish to gain speed rapidly for another thrust into the air. It is estimated that the tail fin may vibrate as rapidly as 50 times per second. By these movements the fish may make several thrusts into the air in rapid succession. Flying fish extend a flight by plunging the vibrating tail into the water to supply added momentum.

When gliding, flying fish barely skim over the surface of the water. Larger fish can leap to a height of 3.3 ft (1 m) above the water and glide for over 330 ft (100 m). A flying fish, however, can be carried to the topmost part of the wave possibly 15 ft (4.5 m) above the trough so that the fish may appear to be high out of the water. It is thought that flying fish fly to escape from predators (such as fish-eating bonitos, albacores, or blue fish), but airborne flying fish are also exposed to fish-eating birds.

Flying fish prefer the warm waters of the Atlantic and Pacific Oceans. Tropical flying fish such as Exocoetus volitans and Hirundichthys speculiger are found in tropical regions of the world where the water temperature is rarely below 68°F (20°C). The flying fish genus Exocoetus includes 22 species found in the Pacific and Atlantic Oceans.

The Atlantic flying fish (Cypselurus heterurus) inhabits the tropical Atlantic and Caribbean, has a black band extending through its wings, and measures less than 10 in (25.4 cm) in length. The California flying fish (Cypselurus californicus) is reputed to be the largest of all the flying fish, growing up to 1.6 ft (0.5 m), and is caught commercially for human consumption. This species is considered a four-winged flying fish, because its pectoral and pelvic fins resemble large wings.

The large margined flying fish (Cypselurus cyanopterus), the bandwing flying fish (Cypselurus exsiliens), and the short-winged flying fish (Parexocoetus mesogaster) are widely distributed throughout the tropical seas. The smallwing flying fish (Oxyporhamphus micropterus) is found in tropical and subtropical waters, and flies only short distance due to its short wings.