Cabrillo Marine Aquarium

Swell Shark

Cephaloscyllium ventriosum


Fun Facts

    When stressed, the swell shark can “swell” by inflating its stomach by swallowing water.

    Swell sharks are nocturnal; they are inactive during the day and become active at night.




The swell shark is a type of catshark that lives on the bottom of the sea floor. They live on rocky reefs, particularly in and around kelp beds and algae-covered bottoms. Swell sharks occur from Monterey Bay, California to southern Mexico. The body is yellow-brown with seven or eight saddlelike bars and numerous dark brown spots. The head is flattened with a short snout. The rounded dorsal fins are set far back on the body.

Swell sharks feed on a variety of crustaceans, such as crabs and shrimps, and small fishes. Most species of sharks give birth to live young, however, approximately 30% of shark species lay eggs. Two local species, the horn shark (Heterodontus francisci) and the swell shark, are egg-layers. Swell shark egg cases are amber-green, smooth, and purse shaped, with tapering horns and long tendrils. The eggs hatch in seven to ten months. The color and texture of the eggs serve to camouflage them as they rest among the debris and rubble of the bottom.

Swell sharks are usually found at the Aquarium in tank number 15 and 35.