U. Minnesota concluded the first-ever complete population count of emperor penguins in Antarctica, with unexpected results.

Using high-resolution satellite imagery technology called QuickBird, researchers at the University’s Polar Geospatial Center counted almost 600,000 penguins –– twice the amount expected, including seven previously unknown colonies.

The PGC, in collaboration with the British Antarctic Survey, the Australian Antarctic Division and Scripps Institution of Oceanography collected the data by monitoring images taken by a satellite, which passed over Antarctica about five times per day. A computer algorithm translated the images into a total population count.

“I’m floored; we’re talking about counting an entire species from orbit,” said Paul Morin, PGC’s director.

Founded in 2007, the PGC provides mapping services for the United States Antarctic Program. In 2009, Peter Fretwell, a geographer with the British Antarctic Survey, approached one of the center’s graduate students, Michelle LaRue, to help with the survey because of her previous work using QuickBird to map dry valleys in Antarctica.

Fretwell’s work on penguin research began in 2008, when his team realized they could identify the locations of emperor penguin colonies by looking for excrement stains on the ice.

But the low-resolution imagery he was using only provided the locations of colonies, not of individual birds, LaRue said. Collaborating with the PGC allowed for a more thorough and complete count. Using the locations of colonies that Fretwell had found, the team was able to zoom in on those locations and see individual birds.

LaRue, who has visited Antarctica four times to conduct field research, described the continent as surreal.

“There’s no sense of scale. I was in the dry valleys, and I was looking up to the top of this nice little hill –– what I thought was a hill –– and it was actually, I believe, deeper than the Grand Canyon,” she said.

But because the survey utilized QuickBird, very little field work was needed for the population count. Traveling to Antarctica by air or by ship is costly, and certain areas are unreachable, LaRue said.

“Having a satellite image really fixes that problem,” she said.

Images used for the population count were taken during the birds’ mating season in October and November of 2009, LaRue said. During mating season, the birds are in a large group that remains more or less in the same place, making them easy to count, she said.

The discovery of twice as many penguins as expected was astounding for the team.

Previous population counts were based on annual visits to a handful of penguin colonies, LaRue said. Field researchers would take the number of penguins they counted and extrapolate to create an estimate of the population’s total size. Before the completion of the survey, researchers believed the emperor penguin population totaled 300,000 at most.

Thanks to the accurate count of the survey, researchers can now monitor population trends over time. There are also plans to observe changes in sea ice due to climate change. Penguins lay their eggs on the ice, and the team is curious to see if the population will be affected by these changes, LaRue said.

The PGC will continue to use QuickBird for other mapping purposes. Cole Kelleher, one of the students working on Antarctic mapping, said a major part of the work is assisting field researchers.

“They can be more efficient and more prepared for what’s out there,” he said.

The PGC has also received funding to expand its research to the Arctic. This will be different, Morin said, because unlike Antarctica, the Arctic is inhabited by about 4 million people, including 2 million in urban areas.

“We forget about this, but the U.S. is an Arctic nation. We have Alaska. … It’s easy to forget that here as we’re sitting outside in Minnesota drinking iced tea,” Morin said.