Flying fish are marine creatures known for launching themselves from water to glide through the air. This adaptation allows temporary escape from the aquatic environment. They do not engage in powered flight like birds, but their aerial excursions are a fascinating spectacle in the open ocean. Specialized physical traits enable these impressive aerial feats.
How Flying Fish Achieve Flight
Becoming airborne involves coordinated movements and specialized anatomy. It begins underwater, where the fish builds significant speed by rapidly oscillating its body and tail, reaching over 35 mph (56 km/h) before breaking the surface. Their streamlined, torpedo-shaped bodies minimize drag during this acceleration.
Upon surfacing, the fish extends its large, wing-like pectoral fins as gliding surfaces. Some species, known as “four-winged” flying fish, also deploy enlarged pelvic fins, providing additional lift and stability. The lower lobe of their unevenly forked tail remains submerged, beating vigorously up to 70 times per second to provide the final thrust needed for full liftoff. This tail-flicking provides momentum as their body lifts.
Once airborne, these fish primarily glide, using rigid fins to generate lift, similar to an airplane’s wings. They can also exploit a phenomenon called ground effect, which increases lift and decreases drag when flying close to a surface, often 50-60 centimeters above the water. The microscopic structure of their fins also helps reduce drag, enhancing gliding efficiency.
Typical Flight Distances
Flying fish typically glide for around 160 feet (50 meters) in a single burst. Under optimal conditions, they can cover greater distances. They have been observed utilizing updrafts at the leading edge of waves to extend their glides, reaching distances of up to 1,300 feet (400 meters). Consecutive glides up to 1,300 feet (400 meters) are possible by dipping their tail back into the water for additional thrust.
The longest documented flight duration is 45 seconds (May 2008), with the fish traveling at an estimated 19 mph (30 km/h), surpassing a 1920s record of 42 seconds. During these glides, flying fish can reach speeds exceeding 43 mph (70 km/h) and heights of up to 20 feet (6 meters) above the water’s surface.
Distance and duration are influenced by several factors. Wind speed and direction play a role, as strong winds provide favorable updrafts for longer glides. Species variations also contribute, as different species have varying body sizes and fin shapes affecting aerodynamic capabilities. Initial underwater speed is also a factor, as greater launch speed translates to more gliding momentum.
Why Flying Fish Fly
Flying fish primarily engage in aerial behavior to evade predators. When threatened by fast-swimming marine hunters like tuna, mackerel, swordfish, and marlin, taking to the air provides a temporary escape route these aquatic pursuers cannot follow. This allows them to disappear from detection and potentially confuse attackers.
While predator evasion is the main driver, some studies suggest additional benefits, such as energy efficiency. Gliding through the air presents less resistance than swimming through water, potentially allowing them to cover greater distances with less energy expenditure. However, the considerable energy cost of initial acceleration for takeoff tempers the overall energy-saving argument.
Gliding also exposes them to new risks, as they become vulnerable to avian predators like seabirds. Despite this, the advantage of escaping marine predators appears to outweigh the risk of aerial predation, supporting this adaptation’s evolutionary success in tropical and subtropical waters worldwide.