Staff Sgt. Mario Hernandez
Staff Sgt. Mario Hernandez, 374th Security Forces Squadron military working dog handler, and military working dog Demo play after a water-based aggression training at Yokota Air Base, Japan, Sept. 12, 2018. The water aggression training offers a unique opportunity for working dogs to become familiar with water.
(U.S. Air Force photo by Yasuo Osakabe)