979-7139 - Chinstrap penguin (Pygoscelis antarctica) chick head detail at colony on Useful Island near the Antarctic Peninsula. There are an estimated 2 million breeding pairs of chinstrap penguins in the Antarctic peninsula region alone, perhaps as many as 7.5 million breeding pairs in all of Antarctica. Their name derives from the narrow black band under their heads which makes it appear as if they are wearing black helmets, making them one of the most easily identified types of penguin. Other names for them are "Ringed Penguins", "Bearded Penguins", and "Stonecracker Penguins" due to their harsh call. They grow to 68 cm (27 in). The average adult weight of a Chinstrap Penguin is 4.5 kg (10 lbs). Weight can range from 3 to 6 kg (6.6-13.2 lbs), with males being slightly larger and weight varying based on where the penguin is in the breeding cycle. Their diet consists of krill, shrimp, and fish. On land they build circular nests from stones, and lay two eggs, which are incubated by both the male and the female for shifts of five to ten days. They can also breed on icebergs, though they prefer non-icy conditions. The chicks hatch after about 35 days, and have fluffy gray backs and white fronts. The chicks stay in the nest for 20?30 days before they go to join a creche. At around 50?60 days old, they moult, gaining their adult plumage and go to sea. The Chinstrap Penguin was first described by German naturalist Forster in 1781. Its specific epithet was often seen as antarctica, however a 2002 review determined the genus Pygoscelis was masculine, and hence the correct binomial name is Pygoscelis antarcticus.
979-7564 - Guests from the Lindblad Expedition ship National Geographic Explorer enjoy a hot asado sandwich prepared by staff at BBQ on an ice floe near Adelaide Island, Antarctica
979-7428 - Adult female leopard seal (Hydrurga leptonyx) stalking, then killing and eating an adult gentoo penguin in Paradise Bay, Antarctica, Southern Ocean
979-7177 - The Lindblad Expedition ship National Geographic Explorer in late evening light as the sun sets in the northwest side of the Antarctic Peninsula in Antarctica.
979-7048 - Brown Bear (Ursus arctos) fishing for pink salmon near the salmon weir at Pavlof Harbor on Chichagof Island in Southeast Alaska, USA. Pacific Ocean.
979-7053 - Brown Bear (Ursus arctos) fishing for pink salmon near the salmon weir at Pavlof Harbor on Chichagof Island in Southeast Alaska, USA. Pacific Ocean.
979-7774 - Reflections in calm water photographed from the Lindblad Expedition Ship National Geographic Explorer operating in Antarctica, Southern Ocean.
979-7412 - Adult female leopard seal (Hydrurga leptonyx) stalking, then killing and eating an adult gentoo penguin in Paradise Bay, Antarctica, Southern Ocean
979-7763 - Guests from the Lindblad Expedition ship National Geographic Explorer take the Polar Plunge off ice floe in the Weddell Sea, Antarctica, Southern Ocean
979-7376 - Full moon (plus 1 day) rising over icebergs in the Weddell Sea, Antarctica. MORE INFO This moonrise occurred on January 1, 2010, the night after the blue moon full of December 31, 2009.
979-7009 - Adult humpback whales (Megaptera novaeangliae) co-operatively "bubble-net" feeding along the west side of Chatham Strait in Southeast Alaska, USA. Pacific Ocean.
979-7759 - Guests from the Lindblad Expedition ship National Geographic Explorer take the Polar Plunge off ice floe in the Weddell Sea, Antarctica, Southern Ocean
979-7187 - Black-browed albatross (Thalassarche melanophrys) chick on nest at breeding colony on New Island in the Falkland Islands, Southern Atlantic Ocean
979-7322 - Adult Fin Whale (Balaenoptera physalus) power lunging in the Drake Passage between South America and the Antarctic Peninsula, Southern Ocean
979-7056 - Brown Bear sow (Ursus arctos) with coy (cubs-of-year) fishing for pink salmon near the salmon weir at Pavlof Harbor on Chichagof Island in Southeast Alaska, USA. Pacific Ocean.
979-7325 - The Lindblad Expeditions ship National Geographic Explorer pushes through ice in Crystal Sound, south of the Antarctic Circle, Antarctica, Southern Ocean
979-7035 - Brown Bear sow (Ursus arctos) with coy (cubs-of-year) fishing for pink salmon near the salmon weir at Pavlof Harbor on Chichagof Island in Southeast Alaska, USA. Pacific Ocean.
979-7030 - Brown Bear sow (Ursus arctos) with coy (cubs-of-year) fishing for pink salmon near the salmon weir at Pavlof Harbor on Chichagof Island in Southeast Alaska, USA. Pacific Ocean.
979-7422 - Adult female leopard seal (Hydrurga leptonyx) stalking, then killing and eating an adult gentoo penguin in Paradise Bay, Antarctica, Southern Ocean
979-7379 - Blizzard conditions cause the ocean's surface to begin to freeze in Dahlmann Bay, Antarctica, Southern Ocean. MORE INFO First signs of grease ice as the surface of the sea begins to freeze.