King penguins, Aptenodytes patagonicus are the second largest penguin species in the world after the Emperor penguin that inhabits the frozen south. There are two sub-species, the South Atlantic group being Aptenodytes patagonicus patagonicus. The penguins weigh about 11-16kg (24-35lb) and stand about 95cm (3.1 feet) tall.

The brown fluffy ones in this picture are unfledged chicks and the ones in the orange-highlighted black and white finery are the adults. The first people to see king penguins identified the youngsters and adults as two distinct species, the young were called the "Woolly Penguin". Unlike most species, kings don't feed on krill, instead their diet consists mainly of fish and squid.

This breeding colony on Salisbury Plain, South Georgia is home to about a quarter of a million individuals, even so, this only makes it the second largest colony on the island.

They have an usual reproductive cycle where they raise 1 chick every 2 years, or at most 2 chicks every 3 years.

These are pictures from a trip to Antarctica in the summer of 2010 - 2011 for the purpose of researching former whaling stations and companies by Ulf Gustafsson of the University of Groningen in the Netherlands.

Pictures copyright Ulf Gustafsson.