Mirounga leonina (southern elephant seals) are found along the coast of Antarctica and on sub-Antarctic islands when breeding or molting. However, before human exploitation they were more common farther north. The largest present population occurs on the island of South Georgia, in the South Atlantic Ocean. Southern elephant seals are also common on Macquarie Island, Heard Island, Kerguelen Island, and the Peninsula Valdez in Argentina. When at sea, M. leonina often journey thousands of miles from their breeding grounds. Despite the occasional sighting, not much is known about their range outside of the breeding season.

Biogeographic Regions: antarctica (Native ); oceanic islands (Native ); indian ocean (Native ); atlantic ocean (Native ); pacific ocean (Native )