West Coast Sea Stars

Sea Stars or Starfish are marine animals called echinoderms, found in many of the world's coastal areas. Seastars are often found in the middle and low littoral zones (the areas furthest from the high tide mark on the shoreline) because their bodies are not designed to be out of the water for extended periods of time.


Most species are generalist predators, eating mollusks such clams, oysters, some snails, or any other animal too slow to evade the attack (e.g. other echinoderms, or dying fish)
Sea stars move using a water vascular system. Water comes into the system via the madreporite. It is then circulated from the stone canal to the ring canal and into the radial canals. The radial canals carry water to the ampullae and provide suction to the tube feet. The tube feet latch on to surfaces and move in a wave, with one body section attaching to the surfaces as another releases. Most sea stars cannot move quickly. However, some burrowing species from the genera Astropecten and Luidia are capable of rapid, creeping motion: "gliding" across the ocean floor. This motion results from their pointed tubefeet adapted specially for excavating patches of sand.

Several types of toxins and secondary metabolites have been extracted from several species of sea star. Research into the efficacy of these compounds for possible pharmacological or industrial use occurs worldwide.
Sea stars are not considered endangered, however, like other marine life, their existence depends on healthy oceans. Recent reports about coastal dead zones along the West Coast, ocean areas that lack oxygen, also include reports of dead sea stars.


1 - Pyloric stomach 2 - Intestine and anus 3 - Rectal sac 4 - Stone canal 5 - Madreporite 6 - Pyloric caecum 7 - Digestive glands 8 - Cardiac stomach 9 - Gonad 10 - Radial canal 11 - Tube feet