As one of the most recognizable ocean animals, this creature brings to mind trips to tide pools, walks along the shore and stays in beach houses, but this “fish” isn’t even a fish at all!
Starfish, or more appropriately called Sea Stars, are actually a type of invertebrate known as echidnoderms (from the Ancient Greek word meaning hedgehog, or spiny, skin).
Sea Stars are more similar to sand dollars, sea urchins and their close relatives the brittle stars, than they are to fish. There are around 2,000 species of sea star, most having the iconic five arms, but some species have 10, 20 and even 40 arms!
Found around the world from coral reefs and tidal pools to kelp forests and the sandy sea bed as deep as 20,000 feet (6,000 meters). Sea stars are marine animals living entirely in saltwater, while some may occur in brackish water, there are no freshwater species.
Sea stars walk by using hundreds of suction cup-like tube feet on the bottom of each arm. Their eyes are actually located on the tips of their arms.
Sea stars also possess the ability to regenerate lost limbs. Some species can regrow almost an entire new sea star from just a portion of an arm. This is possible since all or most of their vital organs are housed in their limbs.
Many sea stars prey mainly upon mollusks like clams and oysters. They eat by expelling their stomach through their mouth and enzymes digest prey allowing them to be consumed.