Flying fish are marine animals known for their ability to launch themselves out of the water and soar through the air. While their name suggests true flight, these creatures do not “fly” like birds with sustained wingbeats. Instead, they are exceptional gliders, using specialized fins to perform aerial maneuvers above the ocean’s surface. This unique adaptation allows them to cover considerable distances in tropical and subtropical waters worldwide.
The Mechanics of Their Aerial Movement
Flying fish begin their aerial movement by building speed underwater, often exceeding 35 miles per hour (56 kilometers per hour). As they near the surface, they propel themselves upwards, breaking free from the water. Their powerful, unevenly forked caudal (tail) fin generates initial thrust, vibrating rapidly at 50-60 beats per second even as the body becomes airborne. Once out of the water, they spread their large, wing-like pectoral fins, which act as airfoils for lift and gliding. Some species also have enlarged pelvic fins, providing additional lift and stability for steering during their airborne trajectory. Their streamlined bodies and rigid vertebral columns further enhance aerodynamic efficiency, reducing drag and increasing glide duration.
Why Flying Fish Take to the Air
Flying fish primarily take to the air to escape predators that pursue them beneath the surface. Predators like tuna, marlin, and dolphins hunt these fish, and launching into a glide allows flying fish to quickly evade immediate danger. This sudden aerial departure can confuse underwater predators, giving the fish a momentary advantage. Gliding also enables them to cover distances faster than swimming, helping them reach safer areas. However, this aerial escape exposes them to a new threat: avian predators such as frigatebirds, which can snatch them from the air.
Distinguishing Gliding from True Flight
The aerial movement of flying fish is a form of gliding, distinct from the powered flight seen in birds or bats. True flight involves continuous, active flapping of wings to generate both lift and thrust, allowing an animal to sustain airborne movement and gain altitude. Flying fish, conversely, do not flap their fins once airborne. They rely on an initial burst of speed and propulsion from their tail in the water to launch. Their specialized fins then act as fixed wings, allowing them to coast on air currents. Their glides are ballistic, meaning they gradually lose altitude unless they dip their tail back into the water for another propulsive burst to extend their flight.