Emperor penguin (Aptenodytes forsteri) feeding journey. This penguin is walking across the ice between the sea and its nesting site during the breeding season. This is the only penguin to breed during the Antarctic winter. Each pair produces a single egg, which the males incubate. Males fast during the two-month incubation period and lose almost half their body mass by the end. After the egg hatches in around mid-July, the male and female take it in turns over the following months to shelter the chick and feed it. This can require long journeys to and from the sea to feed. Photographed in October, in Antarctica.