Flying fish are marine animals known for their extraordinary ability to launch themselves from the water and glide through the air. This remarkable behavior allows them to navigate both aquatic and aerial environments. They are a unique example of the diverse life found in the world’s oceans.
Yes, They Exist!
Flying fish are not mythical creatures, but a diverse group of ray-finned fish belonging to the family Exocoetidae. There are approximately 40 to 70 known species, typically 7 to 12 inches (17 to 30 centimeters) long, though some reach 18 inches (45 centimeters). They possess streamlined, torpedo-shaped bodies, well-suited for rapid movement through water. Their most distinctive features are greatly enlarged pectoral fins, which resemble wings. Some species, known as “four-winged” flying fish, also have enlarged pelvic fins that contribute to their aerial capabilities.
The Mechanics of Their Glide
The aerial movement of flying fish is a glide, not true powered flight, as they do not flap their fins to stay airborne. To initiate a glide, a flying fish first builds up significant speed underwater, often reaching over 35 miles per hour (56 kilometers per hour). They achieve this by rapidly beating their deeply forked caudal (tail) fin, which has a longer lower lobe that provides powerful thrust.
As they approach the surface, they hold their pectoral fins close to their bodies to reduce drag. Upon breaking the water’s surface, the fish spreads its large pectoral fins, which act as airfoils to generate lift. The lower lobe of their tail fin continues to beat rapidly, sometimes up to 70 times per second, providing additional propulsion and steering while the rest of the body is already airborne. Once sufficient speed and lift are achieved, the tail lifts clear of the water, and the fish becomes fully airborne, gliding for considerable distances. Glides typically range from 650 feet (200 meters) and can last for several seconds, with some recorded as long as 45 seconds and covering distances of over 1,300 feet (400 meters), especially when aided by updrafts from waves.
Purpose and Habitat
The primary purpose of their impressive glides is to escape from underwater predators. When faced with threats such as tuna, marlin, swordfish, or dolphins, flying fish can launch themselves into the air, creating a temporary refuge from their pursuers. This aerial escape provides them with an advantage, as many aquatic predators cannot follow them out of the water.
However, this strategy does come with its own risks, as airborne flying fish can become prey for seabirds. Flying fish are found in tropical and subtropical waters across the world’s major oceans, including the Atlantic, Pacific, and Indian Oceans. They typically inhabit the open ocean, staying near the surface in the epipelagic zone, where there is sufficient sunlight. While most prefer the open seas, some species can also be found closer to the outskirts of coral reefs. These warm water environments are ideal for their physiology, as colder temperatures can hinder the muscular function needed for their powerful glides.