Observations of the movement of a colony of emperor penguins challenged the idea that the birds return to the same spot to nest every year.

Researchers have long-thought penguins were philopatric, meaning they return to the same nesting location annually. Satellite images of penguin migration suggest they are more likely to relocate and adapt than researchers previously believed, a University of Minnesota news release reported.

The research team found six instances over the course of three years in which emperor penguins did not return to the same location to breed. They also discovered new colonies in Antarctic Peninsula, suggesting these populations may have relocated.  

"Our research showing that colonies seem to appear and disappear throughout the years challenges behaviors we thought we understood about emperor penguins," lead author Michelle LaRue, said in the news release. "If we assume that these birds come back to the same locations every year, without fail, these new colonies we see on satellite images wouldn't make any sense. These birds didn't just appear out of thin air-they had to have come from somewhere else. This suggests that emperor penguins move among colonies. That means we need to revisit how we interpret population changes and the causes of those changes." 

The "March of the Penguins" colony at Pointe Géologie has been studied for 60 years; researchers have been looking closely at them in recent years to see how they are being affected by receding sea ice. Half of the colony died, possibly as a result of warming temperatures.

"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. "If we want to accurately conserve the species, we really need to know the basics. We've just learned something unexpected, and we should rethink how we interpret colony fluctuations."