Urchin barren (IMAGE) University of California - Santa Cruz Caption In this urchin barren in Monterey Bay, grazing by purple sea urchins has removed kelp and other algae from the rocky reef. Credit Photo by Michael Langhans Usage Restrictions For use only with news coverage of this research License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.