Starfish Facts

About the starfish

About 1,900 species crawl along the ocean floor, from warm tropical waters to icy polar seas and from the tide line down to 6,000 m deep. Many are red or orange, and others come in blue, gray or brown. The top surface can be smooth, grainy or spiny. Underneath, tube feet driven by a water-based hydraulic system move the animal, and the mouth sits in the center.

Starfish are opportunistic feeders and mostly prey on other bottom-dwelling invertebrates. Some push their stomachs outside their bodies to feed, and others strain food from the water. They can reproduce sexually or asexually. Most can regrow damaged or lost arms and may drop an arm to escape danger.

Did you know?

• The crown-of-thorns starfish preys heavily on coral across the Indo-Pacific.
• Starfish are also called asteroids, after their class Asteroidea.
• Brittle stars are often called starfish but belong to a different group.