The Flying Gurnard (Dactylopterus volitans), also called “Helmet Gurnard” is a peculiar marine creature known for its distinct appearance and behavior. Flying Gurnards are bottom-dwelling fish found in tropical to warm temperate oceans.
Contrary to their name, they don’t fly. Instead, they possess an impressive pair of pectoral fins that open up like wings when they get excited or startled. Although uncommon, they have been reported to glide on the water’s surface at very short distances.
Appearance
The Flying Gurnard typically has a boxy elongated body that tapers towards the tail. Its size can vary, but they generally reach a length of 14.9 inches (38 cm). The body varies in color from yellowish-brown to greenish-brown, often featuring pale or yellow patches.
The Flying Gurnard has a large blunt head that is covered in bony scales. They have large prominent eyes, encircled with a bright orange rim, and a small mouth that opens on the underside of their head rather than at the front like most other fish.
The Flying Gurnard’s Wing-Like Fins
The most remarkable feature of the Flying Gurnard is its large, fan-like pectoral fins that resemble wings. These fins are connected to the fish’s body by a sequel of thin, bony rays. When fully extended, they can reach back to the tail. What makes their “wings” appear so striking is that it is semi-translucent with phosphorescent electric-blue spots along the edges.
However, despite their appearance, these wings aren’t for speed. Instead, the Flying Gurnard relies on its dorsal and anal fins for swift getaways.
Along the edges of the fins, the Flying Gurnard has sharp, bony spines that serve as a form of defense. When threatened, they erect these spines by opening their wing-like fins creating a deterrent for potential predators.
These fish also have pelvic fins resembling fingers which they use to “walk” along the seafloor. The Flying Gurnard truly is a master of both style and surprising adaptations.
Diet
The Flying Gurnard’s diet consists mainly of crustaceans like small crabs and shrimps, small fish and bivalves like clams.
The Flying Gurnard is a bottom feeder. It’s finger-like pelvic fins boast specialized inner rays that act like tiny rakes. By skillfully scratching and probing the seafloor, it stirs up a cloud of buried prey. This commotion attracts opportunistic feeders, like Yellow Jack and Coney, that swoop in to snatch the exposed prey.
Habitat
The Flying Gurnard can be found in tropical to warm temperate regions across the globe. It thrives in warm waters with temperatures ranging from 13 to 28 degrees Celsius.
The Flying Gurnard prefers shallow coastal areas. These areas provide a diverse array of habitat types, including estuaries, rocky reefs, seagrass beds, and sandy beaches.
Flying Gurnard’s favor habitats that have soft, sandy or muddy bottoms like reefs and seagrass beds. These ecosystems offer shelter, ample food sources, and protection from larger predators.
Some populations also inhabit estuaries and mangroves. These environments serve as crucial breeding and nursery grounds for various marine species.
The Flying Gurnard is known to even venture out to continental shelves, those gently sloping underwater extensions of continents, where depths can reach up to 328 feet (100 meters). Unfortunately, these deeper forays expose them to the damaging effects of bottom trawling.
Reproduction
Female Flying Gurnards produce eggs inside their bodies, which are then released into the water. The males then externally fertilize these eggs with their sperm. These fertilized eggs drift freely with the ocean currents.
The eggs hatch into larvae that spend months at sea before settling on the seabed. As they mature, they develop their unique “flying” fins.
Breeding likely occurs in the warmer summer months, but much remains unknown about the specific reproductive behavior of Flying Gurnards.
Flying Gurnards generally become sexually mature at around one or two years, depending on environmental conditions and food availability.
Minor Threats
- Habitat Destruction: Coastal development, pollution, and destructive fishing practices such as bottom trawling can lead to habitat degradation and destruction.
- Bycatch: They are unintentionally caught in trawl nets targeting other fish and as bycatch in artisanal fisheries.
Facts About Flying Gurnard
- Along the edges of their pectoral fins, they have venomous spines that can deliver a painful sting if handled or threatened.
- Like their gurnard cousins, Flying Gurnards can make growling noises. Scientists think these sounds, produced with a special swim bladder and muscles, might be how they communicate.
- They may alter their color to blend in with their environment. This gives them good camouflage from potential predators by allowing them to mix in with the sandy or muddy bottoms where they are frequently found.
- They possess large eyes that provide excellent vision, helping them spot prey and navigate the underwater landscape.
- They are found in warm oceans worldwide, inhabiting regions like the Atlantic, Pacific, and Indian Oceans.
FAQs
Are Flying Gurnards venomous?
They have venomous spines on the edges of their pectoral fins to deter predators but it is not harmful to humans.
Do Flying Gurnards fly in the air?
Flying Gurnards are not part of the flying fish family and cannot leap out of the water to “fly” despite what their name implies. Instead, their large wing-like pectoral fins help them to walk across the ocean floor.
Are Flying Gurnards threatened?
According to the International Union for Conservation of Nature (IUCN) Red List, Flying Gurnards are listed as Least Concern. This means that they are still abundant in their natural habitats. West Africa’s unregulated bycatch trade adds to the pressure on their populations.
Are Flying Gurnards fished?
They are not commercially fished but are often caught unintentionally (bycatch) in trawls and Caribbean and West African artisanal fisheries.
Are Flying Gurnards edible?
Despite being considered “trash fish,” they are edible. They are sometimes caught unintentionally (bycatch) in fishing gear like seines, hooks, and traps. In some areas, particularly off West Africa, this bycatch is then sold in local markets for people to eat. It is also processed into fishmeal, animal feed, and even gelatin.
