The Crown of Thorns sea star (Acanthaster pianci) is best known for its voracious appetite for coral. In other parts of the tropical Pacific, periodic population explosions of Crown of Thorns stars have left large patches of reef white and lifeless. In Hawaii, it has not caused problems. Be careful with the Crown of Thorns: its venomous spines can cause painful swelling.

This sea star was photographed in about 25 feet of water off the south Kohala Coast near Puako Beach on the Big Island of Hawaii.