The black seadevil: a rare sighting off the coast of Tenerife

The melanoceto or black devil was spotted on the surface near the coast of Tenerife, an unusual behavior given that it usually lives at depths between 650 to 6,600 feet where sunlight does not reach

The black seadevil (Melanocetus johnsonii), one of the deep-sea fish with a positively ghostly appearance, is one of the most fascinating and mysterious of sea creatures. Typically existing between 650 and 6,600 feet below the surface, where light never penetrates, it was recently spotted on the surface off the coast of Tenerife in the Canary Islands.

The sighting has caught the interest of the scientific community due to its uniqueness. The sighting was photographed by nature photographer David Jara Boguñá and uploaded along with Condrik Tenerife, an organization dedicated to the study of cartilaginous fish.

It is the first video evidence of a live adult black seadevil in daylight near the surface. They are usually only observed using submersible vehicles at deep depths or dead, caught in fishing nets or stranded on beaches.

The features of the black seadevil

Black seadevils belong to the order Lophiiformes, and they are defined by how they hunt, using a bioluminescent appendage known as an illicium that is used as bait to lure victims in. The organ that produces light is located in the head and lures victims in with interest before being consumed in an instantaneous snapping of the jaws. Bioluminescence is a common survival mechanism among the deep-sea dwellers, where sunlight never reaches and it’s dark all over.

The female black seadevils grow to a length of 8 inches and have large, pointed-tooth mouths. The males are much smaller, and in other animals such as these, they are sexual parasites that fuse into the females. With the black seadevil, though, the males separate after they mate and go on to seek out additional mates.

While it appears dangerous, the black seadevil never hurts human beings. It was named after James Yates Johnson, a naturalist who initially wrote about the species in 1863 based on Madeira waters.

Though they are rarely seen, the black seadevil is not endangered. Blasted by an extensive range in temperate, tropical, and subtropical oceans, the species has a secure conservation status. Previously, members have even been seen in Antarctic oceans, demonstrating their adaptability.

Why this bizarre behavior?

So why was this animal seen in shallow waters? Experts have determined several explanations for such bizarre behavior:

• Disease or physiological stress: The fish could have been injured or diseased, causing it to lose control of its position in the water column.
• Upwelling currents: The sea could have had a very strong current, pushing it up towards the surface, an effect which occurs on other deep-sea animals from time to time.
• Escape from predators: The fish could have wandered away from its habitat in a bid to escape being attacked by a predator.