All four species of Antarctic penguins are in decline as a result of climate change according to a World Wildlife Fund report. The Adelie penguin population has plummeted by two thirds and the chinstrap penguins by one third over the last 25 years.. Population numbers on the Emperor Penguin were not quoted, but their nesting grounds have halved in size during the same period. The shrinking sea ice and its impact on lower krill numbers are two factors reducing penguin numbers. Sometimes whole breeding colonies are lost to the ocean when the ice shelf breaks up earlier in the year than has been normal over the last ten millenium.
