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. During the moult, subadult male Elephant Seals often play-fight, testing each other’s strength to establish a dominance hierarchy. This subadult male Southern Elephant Seal was lying huddled with other moulting young seals on a bed of Tussac grass at Gold Harbour, South Georgia. Behind him were Gentoo Penguins at their nests – one pair had two chicks. The young male Elephant Seal raised his head, made his amazing gurgling call, stretched his tail flippers then settled back into the Tussac to doze.