Pacific Electric Ray (Torpedo californica)

In the video: Several torpedo (electric) rays are depicted. Many of them are large fish, in excess of 50 lbs (they can grow to 90 lbs). Divers are included, giving scale to the size of the fish. Since these fish are known to attack divers and therefore are potentially dangerous, a diver uses a pole spear to keep the ray at bay. When the ray wraps its flippers around the pole spear it is most likely emitting an electrical shock in defense. However, the diver in this scene is NOT attempting to injure or harm the ray in any way..just to have it keep its distance while it sends a charge of electricity into the water. These fishes were filmed at Anacapa Island in the northern chain of California's Channel Islands within the boundaries of the Channel Islands National Park.

Additional scenes include bumping other torpedo rays with the underwater camera to get the fish moving and responding....electric rays will attempt to bite a diver instead of getting in a position to shock the diver (by wrapping its fins around him). Biting is not surprising, since the torpedo ray is a relative of sharks.

Morphology and description of Torpedo californica: a member of elasmobranch class of fishes which are mostly sharks and rays. Torpedo rays give live birth. Their habitat is extensive, from Baja California in Mexico north to British Columbia in Canada, both in shallow water and to depths in excess of 1200 feet!

Torpedo rays lack a venomous spine (as is present in other rays) but are capable of producing an electrical shock of some 80 volts. Electric rays have a pair of electrical organs composed of muscle tissue, one on each side of the rounded body disc. Some 400 stacks of cells work similar to electric plates in car batteries. In addition, nerves are configured to to give the rays operational control over these electrical organs, so the electricity generated can be used for defense or to stun prey. The prey is stunned by the electric ray hovering above the victim and wrapping its round fins over the prey and emitting the shock. Although rays cannot maintain a constant current, the electricity generated is very similar to home electricity. There are some 30 species of electric rays with each one generating different levels of electricity. One species (not local) has been documented to produce up to 220 volts of electricity at 20 amps.

Torpedo rays normally feed on fish, crustaceans, and mollusks. Most prefer to lie on the bottom partially covered with sand. This is either a strategy to perhaps ambush prey or simply to rest between other foraging activities.

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