A large bull walrus returns to the shores of Prins Karl Forland after diving and feeding on clams. (Photo by Paul Nicklen/National Geographic). Svalbard, Norway, 2011

Looking toward an uncertain future, a huge male bear triggers a camera trap, taking his own picture. (Photo by Paul Nicklen/National Geographic). Leifdefjorden, Spitsbergen, Norway, 2011

Arctic fox. The photo was taken near the town of Churchill, Canada. Fox listens to Piscu mice, who paved their tunnels under the snow. Upon occurrence of the Arctic winter Arctic fox changes color with brown to ashy, merging with the surrounding tundra snow. (Photo by Paul Nicklen)

Language bubbles. “After an unsuccessful attempt to feed me dead penguins”, – Says Paul, who worked at the Anvers Island, Antarctica, – “A female leopard sea began to show his frustration, blowing bubbles in my direction”. (Photo by Paul Nicklen)

Lyuriki (species of birds), nesting on the rocky shores of Svalbard (Svalbard). (Photo by Paul Nicklen)

Bear, Gudzonov diarrhea, Nunavut, Canada. (Photo by Paul Nicklen)

Svetlospinny sooty albatross nest on the shore of the island of South Georgia, in Golden Bay. It is known, albatrosses lived up to that 40 years, possibly, that this albatross was a witness to the changes on the island. On 1985 , the glacier retreated inland a few miles. (Photo by Paul Nicklen)

Arctic ice is rapidly melting away. (Photo by Paul Nicklen)

The sea leopard. Antarctic. (Photo by Paul Nicklen)

King penguins off the coast of the island of South Georgia, in Golden Bay. (Photo by Paul Nicklen)

The sea leopard. The Antarctic Peninsula. (Photo by Paul Nicklen)

Paul Nickle photographing polar bears in Svalbard. (Photo by Paul Nicklen)