Paul Nicklen of Canada, a photographer working for the National Geographic magazine, has won the first prize in the Nature Stories category of the World Press Photo Contest 2013 with the series &quot;Emperor Penguins&quot;. The picture shows a group of Emperor Penguins swimming in the Ross Sea, Antarctica, taken on November 18, 2011 and distributed by the World Press Photo Foundation February 15, 2013. (Paul Nicklen/National Geographic via Reuters)