Devil fish

What it is

The devil fish, also known as the giant devil ray, is a large member of the Mobulidae family. It is the third-largest species in its genus, surpassed only by oceanic and reef manta rays. This ray is distinct for possessing a spiny tail, a feature unique among devil fishes. Adults typically reach a disk length of 3.5 metres. Its cephalic flaps roll up to resemble horns, creating a silhouette that inspired its common name. While some records suggest a width of 5.2 metres, these figures are likely misidentified giant oceanic manta rays.

Where it lives

This species is most abundant in the Mediterranean Sea, particularly in the eastern basin and Adriatic Sea. Large groups in the Levantine basin may indicate key mating grounds. It also inhabits the Eastern Atlantic near Ireland and Portugal, plus parts of the Pacific. The rays live in offshore and neritic waters, diving as deep as 700 metres but mostly staying within the top 50 metres. They prefer warm temperatures between 20 and 29 degrees Celsius and migrate seasonally across the Mediterranean to follow productive waters.

How it lives

Giant devil rays are epipelagic creatures with an average lifespan of 20 years. They feed on planktonic crustaceans like northern krill and small mesopelagic or clupeid fishes. Cephalic flaps help funnel food into their mouths. Observations show they usually swim in small clusters, though groups of up to 18 have been seen. Deep dives occur at random times rather than specific daily intervals. Their low reproductive capacity makes them sensitive to environmental shifts and population declines.

Breeding and life cycle

The species is ovoviviparous, meaning eggs hatch inside the mother before live young emerge. This internal development allows pups to be more mature at birth. Females give birth to a single offspring, though the time between births remains unknown. Records from the Osaka Aquarium note that newborn pups have a disk width of approximately 1.03 metres. This slow reproductive rate limits the population's ability to recover from losses.

Fish and people

Fisheries in Gaza and Egypt catch these rays for local consumption. However, most mortality results from bycatch in swordfish nets, longlines, and tuna traps. Industrial waste and pollution in the Mediterranean also threaten their survival. The species has been targeted by commercial and recreational fishers for centuries. Its horn-like appearance and large size make it a notable, though often accidental, catch in various global fisheries.

Status and threats

Listed as critically endangered as of 2025, the population is decreasing rapidly. Threats include high bycatch mortality and a naturally slow reproduction rate. Models predict a further 50 per cent decline over the next 60 years. Legal protections exist in Italy, Croatia, and Albania, where trade and landing are forbidden. The species is also covered by the Bern and Barcelona conventions. New Zealand classifies it as data deficient but secure overseas.

Questions people ask about Devil fish

Good reading and sources

• Devil fish on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data