U.S. Navy Electrician's Mate 2nd Class Andrei Krkun and Sonar Technician 3rd Class Mason Stickley, both search and rescue swimmers aboard the guided missile destroyer USS Donald Cook, participate in a swim call in the Mediterranean Sea July 9, 2014. The Donald Cook was underway in the U.S. 6th Fleet area of responsibility supporting maritime security operations and theater security cooperation efforts.