Wolf (IMAGE) Ecological Society of America Caption Wolves were reintroduced to Yellowstone in 1995 and 1996. Credit Credit: Arthur Middleton, University of Wyoming (pictures taken January 2008) Usage Restrictions None 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.