Flying fish are planktivores that feed primarily on tiny crustaceans called copepods, along with other small organisms drifting near the ocean surface. A detailed gut-content study of eight species in the eastern tropical Pacific found that six of them had diets composed of 58 to 97 percent copepods by number, though each species targeted different copepod families.1PubMed. Flyingfish feeding ecology in the eastern Pacific: prey partitioning within a speciose epipelagic community The remaining species had broader diets that included amphipods, small molluscs, and larval fish. Their habitat spans warm tropical and subtropical oceans worldwide, and the specifics of where they concentrate and what they eat reveal a more interesting story than “small fish eats small things.”
The Copepod-Heavy Diet
If you could peer inside the stomach of most flying fish, you would find it packed with copepods, the rice-grain-sized crustaceans that swarm in almost every ocean. Copepods are among the most abundant multicellular animals on earth, and for flying fish they are the dietary staple. The eastern Pacific study examined gut contents of 359 individual flying fish collected during nighttime dip-net fishing and found copepods dominating the diets of six out of eight species analyzed.1PubMed. Flyingfish feeding ecology in the eastern Pacific: prey partitioning within a speciose epipelagic community This makes flying fish functionally similar to many other small pelagic planktivores: they occupy the lower-middle rungs of the open-ocean food web, converting zooplankton into fish biomass that larger predators then consume.
Beyond copepods, the secondary items on the menu include amphipods (another small crustacean), pteropods and other tiny molluscs, and the larvae of other fish species. These supplementary prey items matter more for some species than others. Two species in that same study, the whitetip flyingfish and the mirrorwing flyingfish, had notably generalized diets, consuming roughly equal proportions of amphipods, copepods, molluscs, and larval fish rather than fixating on copepods alone.1PubMed. Flyingfish feeding ecology in the eastern Pacific: prey partitioning within a speciose epipelagic community So while “copepods” is the safe one-word answer to what flying fish eat, the full picture depends on which species you are asking about.
How Different Species Split the Menu
One of the more surprising findings from flying fish diet research is how neatly species that live in the same waters avoid competing with each other for food. Even among the copepod specialists, each species zeroes in on different copepod families. The barbel flyingfish, for instance, focused heavily on euchaetid copepods, which made up over half its diet by number. The banded flyingfish preferred pontellid copepods. The tropical two-wing flyingfish and the bigwing halfbeak both favored calanoid copepods.1PubMed. Flyingfish feeding ecology in the eastern Pacific: prey partitioning within a speciose epipelagic community
This kind of resource partitioning is a well-known phenomenon in ecology, but it had not been documented in detail for flying fish communities before the 2013 eastern Pacific study. The researchers hypothesized that this prey partitioning helps stabilize the community: multiple flying fish species can coexist in the same patch of ocean because they are not all fighting over exactly the same food. It is a bit like several restaurants sharing a food court, each serving a different cuisine from the same set of ingredients.
The practical implication is that flying fish diversity and diet cannot be treated as a single story. The family Exocoetidae contains roughly 70 recognized species worldwide, spread across warm oceans. Differences in body size, gill-raker spacing (the comb-like structures that filter food from water), and feeding depth all contribute to which tiny organisms end up in which species’ stomach. Lumping them all together as “plankton eaters” is technically correct but obscures the ecological nuance that keeps these communities functioning.
When and How They Feed
Flying fish are surface-dwelling (epipelagic) animals that spend their lives in the upper layer of the open ocean, generally within the top few meters. Their feeding behavior is closely tied to this habitat. Many of the zooplankton they eat migrate vertically each day, rising toward the surface at night and descending to deeper water during daylight. This pattern means flying fish often do their heaviest feeding after dark, which is why the eastern Pacific diet study collected specimens during hour-long nighttime fishing sessions.
Their feeding method is essentially filter-feeding at small scales. Flying fish swim through patches of plankton with their mouths open, using their gill rakers to strain out prey items. They do not chase down individual copepods the way a bass might strike at a minnow. This passive style of feeding is efficient in plankton-rich waters, but it also means flying fish are vulnerable to ingesting anything plankton-sized that happens to be suspended in the water column, a detail that becomes important when we get to the issue of microplastics.
It is also worth noting that flying fish do not use their famous gliding ability to catch food. The spectacular launches out of the water, where they spread their enlarged pectoral fins and glide for distances that can exceed 50 meters, are an escape strategy. When a predator closes in from below, a flying fish taxies along the surface, beats its tail to gain speed, and takes to the air. Feeding happens entirely underwater, in the normal way fish feed.
Where Flying Fish Live
Flying fish are found in tropical and subtropical oceans around the world, roughly between 35 degrees north and 35 degrees south latitude. They are open-ocean animals, meaning they spend most of their lives far from coastlines over deep water. You are unlikely to see them in shallow bays or estuaries; they belong to the blue-water realm.
Temperature is the single biggest factor determining where specific flying fish species turn up. Habitat modeling of 12 species in the eastern tropical Pacific found that mean sea surface temperature was the most important predictor for 11 of them, contributing anywhere from about 19 to 42 percent of each model’s explanatory power.2PubMed Central. Flyingfish (Exocoetidae) species diversity and habitats in the eastern tropical Pacific Ocean Salinity and phosphate levels were the next most important variables. One species, the banded flyingfish, was the exception: salinity ranked as its top predictor, with temperature a close second.2PubMed Central. Flyingfish (Exocoetidae) species diversity and habitats in the eastern tropical Pacific Ocean
What this means in practical terms is that flying fish track warm water. As ocean temperatures shift seasonally, so do flying fish populations. Fishers in the Caribbean, Southeast Asia, and the western Pacific have long known this, timing their flying fish seasons to coincide with warm-water currents. Climate-driven changes to sea surface temperature are a concern for flying fish distribution, though the research on long-term shifts is still limited.
The Connection to Floating Debris and Sargassum
Flying fish have an unusual relationship with floating objects. Many species deposit their eggs on drifting material like seaweed, palm fronds, feathers, or even discarded rope. Research in the eastern Caribbean found that eggs and floating substrata at the surface were surprisingly rare, leading to the suggestion that flying fish may typically spawn on floating material until it becomes waterlogged and sinks, or that they spawn directly on submerged substrata below the surface.3Marine Ecology Progress Series. Distribution and relative abundance of flyingfish (Exocoetidae) in the eastern Caribbean. II. Spawning substrata, eggs and larvae Either way, the availability of drifting material in the open ocean appears to be important for their reproductive cycle.
This reliance on floating substrata connects flying fish to another ocean phenomenon: Sargassum seaweed. Surveys across the entire North Atlantic documented that fish were observed more frequently when holopelagic Sargassum was present and when it was aggregated together in mats, with statistically significant associations in the Tropical Atlantic and the Sargasso Sea.4PeerJ. In situ observation of holopelagic Sargassum distribution and aggregation state across the entire North Atlantic from 2011 to 2020 While that survey counted fish broadly rather than flying fish specifically, Sargassum mats are well-known nursery habitats for a range of pelagic species, and flying fish are frequently associated with them. The mats provide both spawning substrate and shelter for larvae, and the plankton communities that cluster around Sargassum offer a concentrated food source.
The recent dramatic increase in Sargassum blooms across the tropical Atlantic is a double-edged development for species that rely on floating weed. More Sargassum could mean more spawning habitat, but massive beach strandings and decomposition events can degrade nearshore water quality. For an offshore species like flying fish, the net effect remains unclear.
Flying Fish as Prey for Larger Animals
Understanding what flying fish eat is only half the ecological picture. They are themselves a critical food source for some of the ocean’s most commercially and ecologically important predators. Tuna, dolphinfish (mahi-mahi), swordfish, and marlins all feed heavily on flying fish in tropical waters. Research on larval fish diets identified flying fish as a principal prey item for both tuna and seabirds.5PubMed Central. Prey-size plastics are invading larval fish nurseries
Seabirds are perhaps the most visually dramatic flying fish predators. Red-footed boobies, for example, have evolved a specific active hunting behavior for chasing flying fish, taking advantage of wind to reduce their own energy expenditure through extensive gliding while pursuing these fast-moving targets.6PubMed Central. The three-dimensional flight of red-footed boobies: adaptations to foraging in a tropical environment? Frigate birds, terns, and other tropical seabirds also take flying fish, sometimes catching them mid-glide as the fish try to escape underwater predators only to find airborne ones waiting.
This position in the food web, converting plankton into prey for commercially valuable fish and charismatic seabirds, gives flying fish outsized ecological importance relative to their small body size. They are a kind of bridge species: what happens to flying fish populations ripples both downward (affecting plankton communities through reduced grazing) and upward (affecting predator populations that depend on them). Stable isotope analysis of flying fish tissue has been used to trace these trophic relationships, with nitrogen isotope ratios in flying fish correlating with body size, likely reflecting subtle dietary shifts as individuals grow larger and can consume slightly bigger prey.7Oceanological and Hydrobiological Studies. Correlation between δ13C and δ15N in flying fish (Exocoetus volitans) muscle and scales from the South China Sea
The Microplastic Problem
Because flying fish feed by filtering small particles from the water column, they are especially vulnerable to ingesting microplastics, the tiny fragments of degraded plastic waste that now pervade the world’s oceans. Several studies have documented this contamination across different regions and species.
Near Easter Island in the southeastern Pacific, researchers examined a flying fish species endemic to the island (Cheilopogon rapanouiensis) and found that about 16 percent of individuals had ingested microplastics. Most of the plastic pieces resembled the planktonic prey the fish normally eat, suggesting the fish cannot distinguish between food and debris of the same size and shape.8PubMed. Plastic ingestion and trophic transfer between Easter Island flying fish (Cheilopogon rapanouiensis) and yellowfin tuna (Thunnus albacares) from Rapa Nui (Easter Island) That same study examined trophic transfer, documenting the pathway by which plastics move from flying fish into the yellowfin tuna that eat them. If the flying fish has plastic in its gut and a tuna eats that flying fish, the plastic moves up the food chain.
A separate investigation of flying fish (Parexocoetus mento) sold at a fish market in Lombok, Indonesia, detected five types of microplastics in their edible tissue: fragments, filaments, film, foam, and pellets. Fragment-type particles were the most abundant, averaging over 360 particles per fish.9IOP Conference Series: Earth and Environmental Science. Microplastics evaluation in edible tissues of flying fish (Parexocoetus mento) from the Bintaro fish market, Lombok, Indonesia This is concerning because in many parts of Southeast Asia and the Caribbean, flying fish are a regular part of the human diet. Barbados, for instance, is sometimes called “the land of the flying fish” and features the species prominently in its cuisine and national identity.
Larval flying fish face the same problem at an even earlier stage. A study of larval fish nurseries off Hawaii found plastics in seven out of eight fish families examined, including flying fish, and noted that the plastic pieces were sized to match the prey that larvae feed on.5PubMed Central. Prey-size plastics are invading larval fish nurseries Larval fish are even less equipped than adults to avoid ingesting plastic, and the developmental consequences of doing so are still being studied. The fact that flying fish nursery areas overlap with zones of high plastic accumulation, both tend to concentrate at ocean convergence zones where floating material aggregates, makes this a particularly stubborn problem.
Flying Fish in Human Fisheries
Flying fish are commercially harvested in several parts of the world. The Caribbean is probably the best-known region for flying fish fisheries, with Barbados and Trinidad and Tobago historically landing the largest catches. In the western Pacific, Taiwan has a significant flying fish fishery, and the Tao people of Orchid Island (Lanyu) have built an entire cultural tradition around the seasonal arrival of flying fish. Japanese fisheries also harvest flying fish, where the roe (known as tobiko) is widely used as a sushi garnish.
The economics of flying fish fisheries are tightly linked to the animals’ ecology. Because flying fish are attracted to light, many fisheries use lights at night to draw them to the surface, where they can be scooped up with dip nets. This method works precisely because flying fish feed at or near the surface after dark, concentrating where plankton density is highest. The same feeding behavior that makes copepods their primary food source makes them catchable by relatively low-technology methods.
Overfishing is a concern in some regions. In the Caribbean, catches of the fourwing flyingfish have declined in some areas over recent decades, prompting management discussions. Because flying fish depend on specific temperature and salinity conditions, and because their reproductive cycle relies on the availability of floating spawning substrata, they are sensitive to environmental changes on multiple fronts simultaneously. A warming ocean might shift their range, while increasing plastic debris could simultaneously degrade their spawning habitat and contaminate their food supply.
Why the Glide Has Nothing to Do with Dinner
A common misconception about flying fish is that their aerial ability is somehow related to feeding, perhaps catching insects above the surface or diving from height onto prey below. There is no evidence for this. Flying fish are not aerial feeders. Their wing-like pectoral fins evolved under intense predation pressure: being able to leave the water for several seconds and glide dozens of meters is an extremely effective way to escape underwater predators like tuna and dolphinfish. Some four-winged species also have enlarged pelvic fins that provide additional lift.
The glide is purely defensive. Underwater, flying fish are ordinary small planktivorous fish. They feed in the same manner as many other comparably sized species, filtering small organisms from the water column. Their eyes are adapted for underwater vision, and while they may have some ability to orient during a glide, they are not scanning the surface for food while airborne. The jaw structure of flying fish is consistent with planktivory: relatively small mouths, fine gill rakers, and no significant dentition for seizing large prey.
This disconnect between their most famous trait and their actual feeding ecology is part of what makes flying fish so interesting to biologists. Their evolutionary story is about predator evasion, not foraging innovation. The dietary niche they fill, converting zooplankton into biomass available to large pelagic predators, is one shared by many small open-ocean fish. What sets flying fish apart is not how they eat but how they avoid being eaten.