Eastern Atlantic Ocean, Mediterranean Sea
Benthic or bottom habitats including rocky reefs, seagrass beds and muddy flats
Order Torpediniformes (electric or torpedo rays), Family Torpedinidae (electric or torpedo rays)
The marbled electric ray, also known as the marbled torpedo ray, is one of many ray species that will literally leave prey in shock. Equipped with electric organs, this ray is an advanced ambush predator whose mottled skin color renders it nearly invisible to unsuspecting eyes.
Marbled electric rays are commonly found in the eastern Atlantic Ocean bordering Africa up to Norway, as well as parts of the Mediterranean Sea. In rocky reefs and seagrass beds, the marbled electric ray buries itself in muddy bottoms during the daylight hours. Oftentimes, only the ray’s eyes are visible above the sand. The black and brown speckled skin of these rays, resembling dark marbled floors, is ideal for camouflaging against the seafloor habitats where they live. At night, the marbled electric ray departs from its hiding spot to forage for prey. Marbled electric rays are generally found in waters no more than 100 feet deep.
Electric rays are unique from other rays in that they lack venomous scales or barbs. Instead, electric rays generate a strong, electric discharge from massive and highly specialized electrogenic organs situated at the base of the pectoral fins. As an ambush predator, the marbled electric ray will wait patiently in the dark hours of the night until fish, such as gobies, mackerel or damselfish, swim pass. Then, the ray jumps on prey while emitting electrical shocks to stun it. These shocks may produce a charge up to 200 volts, instantly stunning or killing prey before the ray can distend its jaw for swallowing. Because of this ray’s formidable demeanor, few other predators of the sea dare to hunt electric rays. Some sharks and other large carnivorous fish have been known to confront marbled electric rays. Not much is known about the reproductive strategies of marbled electric rays, but scientists believe that the gestation period lasts up to 10 months and females may release 5 to 32 young. At birth, young marbled electric rays measure less than six inches on average, but already possess fully functional electric organs to capture prey.
The conservation status of the marbled electric ray remains data deficient as defined by the IUCN Red List, but these rays are known to be a product of bycatch in some trawl fisheries and bottom longlines. Marbled electric rays are not commercially important, so are often discarded back at sea if caught. Catch rates and population trends are hard to assess across the ray’s range.
1. Marbled electric rays can be found anywhere from 33 to 328 feet (10 to 100 m) deep.
2. Female marbled electric rays are larger than males, growing to a maximum length of 2 feet (0.6 m), while males grow to be 1.2 feet (0.4 m) long.
3. Marbled electric rays can produce up to 200 volts of electric discharge at a time.
4. The electric organs of marbled electric rays are functional before the rays are born and can be used to stun prey the moment they’re born.1
5. Marbled electric rays are nocturnal, burying themselves during the day and hunting at night.
6. Marbled electric rays can swallow fishes larger than the width of their closed mouths by expanding their jaws.
7. Marbled electric rays are also known as torpedo rays because of their scientific name Torpedo marmorata. In Latin, Torpedo is derived from “torpinus,” which refers to the numbing effect of the animal’s electric shock on other animals.2
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