Southern Elephant Seals (Mirounga leonina) are massive – mature males grow to 5.8 metres (19 feet) long and weigh up to 4,000 kilograms (8,800 pounds), and are typically five to six times heavier than females. Elephant Seals are true seals, and are unable to walk with their flippers and have no external ear visible. Mature bull Elephant Seals arrive on the beaches of South Georgia island in August, and pregnant females follow in September or October to give birth to a single pup. The “beachmaster” males round up as many females as they can in harems, and aggressively defend them against “bachelor” males. Pups are weaned in about a month, and are left behind as their mothers and dominant bulls return to sea. Immature males and some females remain behind, often to moult. Moulting Elephant Seals are tactile, often huddling together in groups on the beach. Two huddling Elephant Seals were dozing on the beach at Gold Harbour, South Georgia – one was scratching an itch with his front flipper.