Elk Migrate in Yellowstone (IMAGE) University of California - Berkeley Caption Yellowstone's migrating elk use climate cues, like melting snow and greening grasses, to decide when to make the trek from their winter ranges in prairies and valleys to their summer ranges in high mountain plateaus, shows a new UC Berkeley-led study. Credit Joe Riis Usage Restrictions Image only to be used in conjunction with Arthur Middleton's work 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.