Cabrillo Marine Aquarium

Bat Star

Asterina miniata


Fun Facts

    When two bat stars bump into each other they begin a slow-motion “arm wrestling” match. Each sea star tries to get its arm on top of the other’s arm.

    Bat stars are scavengers, eating dead and decaying animals on the sea floor.



  The bat sea star is found from Alaska to Baja California in the low intertidal zone to about 950 feet on rocky and sandy bottoms. Bat stars usually have five webbed arms with suction-cup tube feet that allow it to move and hold onto rocks. They are capable of growing back lost arms. Although most commonly orange or light red, bat sea stars' colors vary from tan, orange, red or maroon and attain lengths of up to 20 cm. 

A bat sea star will eat almost anything (plant or animal) and is capable of turning its stomach inside out. The food is then actually digested externally. Bat sea stars reproduce by spawning and have separate sexes. Other sea stars include the ochre sea star.

Bat stars are usually found at the Aquarium in tank number 6 and in the Tidepool Touch Tank.