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Bat starfish

Patiria miniata

Description: Bat starfish (Patiria miniata) get their common name because of the webbing between their arms (rays). They come in many different colors ranging from brown, green, purple, orange, red and yellow. The color can be solid or mottled. They usually have five arms (rays), but can have as many as nine. In order to breath, they have gill-like structures on the back that works like respirators.

Size: Bat starfish can get up to eight inches (20.3 cm) across.

Behavior: Bat starfish may ‘fight’ with one another, but this fighting behavior is usually pushing and laying an arm over the other. When turned over, they can right themselves by using their tube feet and arms to perform a slow somersault.

Diet: They are omnivores (eat both animal and plant) and scavengers. They feed on surfgrass, algae, bryozoans, sea urchins and sponges, to name a few. In order to eat, they cover their prey with their stomach and then ooze digestive juices over it; thus liquefying the food so that it can be digested.

Senses: It has visual sensors at the end of each arm that can detect light and prey.
Reproduction: Bat starfish reproduce through spawning. The male discharges sperm and the female drops eggs. The sperm and egg unite at sea and are carried away by ocean currents.

Habitat/range: They can be found along the Pacific coast from Alaska to Mexico on rocks, sand bottoms, and among surf grass and kelp forests.

Status: Bat starfish are common; not listed or evaluated.