In the 1970s, biologists noticed that the Pointe Géologie colony -- the group made famous by the "March of the Penguins" documentary -- had diminished in size. Scientists assumed that rising ocean temperatures and melting ice had killed off many of the penguins. But new evidence suggests members of the colony branched off and joined other groups.
In recent years, scientists have been better able to track the location of penguin colonies in Antarctica. Using satellite imagery scientists can quickly and easily pick out the stains of the species' dark fecal droppings against the pristine snow and ice.
"They are the only species living on the very white ice and they leave a very brown stain -- it's pretty obvious," said Michelle LaRue, researcher at the Polar Geospatial Center at the University of Minnesota in Minneapolis.
LaRue is the lead author of a new study suggesting the emperor penguin's propensity for movement motivated by climate change.
Detailed satellite imagery revealed that several other colonies are closer to the Pointe Géologie colony than scientists knew. This new knowledge enabled LaRue and her colleagues to entertain the idea that penguins might abandon one colony and move to another in response to warming temperatures.
Penguins are philopatric, which means they meet every year in one spot to mate. But faced with warming temperatures and shrinking ice, LaRue suggests that they may abandon their favored spot for new lovers and new territory.
"It's possible that birds have moved away from Pointe Géologie to these other spots and that means that maybe those banded birds didn't die," LaRue said.
LaRue presented her findings at IDEACITY conference in Toronto last week, and her study will be published in the upcoming edition of the journal Ecography.