What is the size of the purple sea urchin and where is it typically found?

The purple sea urchin (Strongylocentrotus purpuratus) typically measures about 3 to 4 inches in diameter. It is commonly found along the Pacific coast of North America, particularly in rocky intertidal zones and kelp forests from Alaska to Baja California. These sea urchins thrive in areas with strong wave action, which helps them access their primary food sources, including algae.