Physical Description

  • A ray with a very round disk, measuring up to 4.5 feet in length.
  • Has a tall dorsal (back) fin near its large caudal (tail) fin, on a very stocky tail.
  • Dark gray coloration on top, with irregular dark spots, and a pale white belly underneath.
  • Males grow up to 36 inches long, and females up to almost 54 inches long.


  • Northern British Columbia, Canada to Magdalena Bay, Baja California, Mexico.


  • Lives over sandy bottoms around rocky reefs and kelp beds.
  • Found at depths of 10-100 feet off of California; off of Baja often found at depths of 330-650 feet.


  • Males mature at 7 years old and females at 9 years old
  • Pups are born inside eggs within the mother’s uterus.
  • Gestation lasts 8-10 months.
  • Litters are usually 17-20 pups, that are 7-9 inches long. The young will double their size in the first year of life.
  • There is no definitive birthing season but males are thought to mate every year and females every other year.


  • Halibut, mackerel, flatfish, kelp bass, anchovies, hake, herring, cephalopods.
  • They slowly drift over unsuspecting fishes and stun them with their electrical charge.


  • Has few natural predators due to large size and electrical shock capabilities.
  • Predators include large sharks and large carnivorous fish.

Interesting Facts

  • The Pacific electric ray has two kidney-shaped electric organs on sides of its head, that it uses for hunting and defense. Its shock can be as strong as 45 volts or more! 
  • The ancient Greeks and Romans used the electric current of the electric ray to treat ailments like gout and headaches. Their current is still used for biological and medical research. The word narcotic comes from the Greek word for this fish, “narke,” meaning “numbfish.”
  • These rays are known to be aggressive with divers and even pursue them, so watch out! However, there are no recorded cases of them harming humans. 

Sources: Florida Museum; Monterey Bay Aquarium

Photo: Howard Hall