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Today on Animal Fact Files we’re discussing electric rays. Technically speaking, all animals produce electricity. Your brain right now is powered by natural electricity that your body produces. There are some animals, however, that can produce far greater quantities of electricity and some of these animals are today’s subjects. There are approximately 60 species of electric rays living today, though this number can fluctuate based on most recent information. Electric rays are found in marine waters around the world. They mostly inhabit tropical and subtropical shallow waters specifically living in areas with sandy or muddy bottoms, but some species may live in cooler temperate waters, some may live in deep water more than 3,000 feet (914m) down, and others are known to travel in the open ocean. Most electric rays, however, are benthic, meaning they stay towards the bottom of the water column.

Electric rays rest during the day. They may bury themselves in sand and be nearly imperceptible, but they can quickly strike any would-be predator or potential meal if one swims close by. At night, electric rays swim along the ocean floor in search of food. They are related to sharks and can thus utilize electroreceptors, called ampullae of lorenzini, to find invertebrates and fish hidden in rock crevices or under the sand. An electric ray is typically a sluggish swimmer, but they are able to catch fast swimming fish by numbing them with electrical charges released from specialized muscles in the ray’s body which store electricity. These muscles are kidney bean shaped, appear on each side of the electric ray’s head, and can make up ⅙ of the ray’s body weight. In size, electric rays range from 1 to 6 feet (30.5-183cm) long and can weigh up to 200 pounds (90.7kg) - which in the case of the largest electric rays would be over 30 pounds (13.6kg) of shocking muscle. The charges produced by an electric ray can be strong enough to knock out a human and are the reason these fish don’t have natural predators - no one in the ocean wants to mess with them! Still, their voltage doesn’t quite match up to the electric eel. An electric rays voltage ranges from 8 to 220 volts; an electric eel’s voltage can reach over 800 volts! We encourage you to check out our electric eel episode to learn more!

Electric rays are classified into four different families and may also be known as numbfishes, sleeper rays, coffin rays, and torpedo rays - though we wouldn’t necessarily say they look like torpedoes. These fish are more like big, swimming pancakes. Pancakes with tails to be precise. Electric rays don’t have stingers because they have their electricity to keep them safe. They may have no to two dorsal fins and their caudal, or tail fins, can be quite large! They actually use these tail fins to swim the same way a shark would! Electric rays have small eyes and sometimes their eyes are completely covered by their skin. Considering they’re nocturnal animals and they use other senses to hunt, they don’t really need their eyes to find food! They also have holes in their heads called spiracles which are used for bringing in water over the rays’ gills - we talked about these in our freshwater stingray episode as well.

There isn’t much information on how electric rays go about finding a mate. It is known that the females, who are often larger than the males, produce eggs. These eggs remain in the body until they hatch at which point the electric ray babies are born live. An electric ray mother may give birth to two to 60 pups at a time! These little rays are able to produce electricity as soon as they are born so they can take care of themselves as they set off to live their lives which may be more than a decade long!

For more facts on electric rays, check out the links in the description. Thank you to Jayson Sumner for today’s request! Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files!