U.S. Navy Petty Officer 2nd Class Michael Gerstel, a handler assigned to the Marine Mammal Company of Explosive Ordnance Disposal Mobile Unit, rewards a bottlenose dolphin after a successful training program at Joint Expeditionary Base Little Creek-Fort Story, Va., during Frontier Sentinel 2010 on June 8, 2010. An estimated 2,500 Canadian and U.S. military personnel and government civilian agency members are participating in the annual maritime homeland security training exercise.