Male Koalas Raise their Voices to Avoid Conflict (image) University of Queensland Share Print E-Mail Caption San Diego Zoo's Ric Schwartz (left) and UQ's Dr. Bill Ellis with a koala participating in the radio tracking study. Credit Ken Bohn - San Diego Zoo. Usage Restrictions Usage only with credit supplied to Ken Bohn, San Diego Zoo Share Print E-Mail 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.