These slow moving and often colorful intertidal and sub-tidal critters are relatives of the sea urchin, sand dollar, and sea cucumber. They are some of the most conspicuous and brightly colored creatures encountered in tide pools throughout most of the maritime region of Alaska.
Most starfish have spiny or warty skin that is supported by tiny bone-like plates.
Numerous protruding spines keep most predators at arm's reach. There are many common varieties of starfish. Identification can be made with the assistance of a good guide to marine intertidal invertebrates. Starfish range in size from an inch in diameter to nearly a yard in diameter. The more commonly encountered tide pool stars include the purple or orange Pisaster and the mottled star , Evasterias , with its narrower tipped arms.