Govert Schilling, LiveScience Contributor
Date: 06 January 2013
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A colony of Adélie penguins on the West Antarctic Peninsula. CREDIT: Sue & Wayne Trivelpiece |
— Suppose someone monitors your whole life, from the moment you were born through childhood, puberty, adolescence and your midlife crisis, all the way to your ultimate death — recording what you eat, where you go, who you make love to, when you raise children and how your body ages. Pretty scary, right?
But that's exactly what biologist David Ainley is doing. Not with humans, but with Adélie penguins in Antarctica. If he could put TV cameras in the birds' master bedrooms, he wouldn't hesitate.
No detail too private
For 17 years now, Ainley has studied three penguin colonies in and around McMurdo Sound, located at the southern extent of the Ross Sea. "It's rare in science to collect data throughout the whole age structure of a population," Ainley told LiveScience, noting Adélie penguins live, on average, about 20 years. Some of the sedate, elderly colony members were just "screaming" newborn chicks when he first arrived here in 1996.
Don't ask these guys to tap dance. Adelie penguins in Antarctica.
CREDIT: Dr. Robert Ricker, NOAA/NOS/ORR
CREDIT: Dr. Robert Ricker, NOAA/NOS/ORR
Back then, the three colonies were growing rapidly, at a rate of about 10 percent per year. "My original goal was to find out what caused this increase, and why the smaller colonies grew even faster than the larger ones," said Ainley, who is a biologist at H.T. Harvey & Associates, an ecological consultancy in San Jose, Calif.
Surprisingly, the baby boom turned out to be a side effect of the Antarctic ozone hole (an opening in the protective atmospheric layer), which reached huge dimensions in the 1990s. "A larger ozone hole means a cooler stratosphere, a more powerful polar vortex and, as a result of stronger winds, more open water in the immediate neighborhood of the colonies," he said. The penguins need the open water for finding their favorite foods — krill and fish.
With funding from the U.S. Antarctic Program, through the National Science Foundation, Ainley has discovered a lack of competition for scarce food resources is what drives the smaller colonies to grow faster than larger ones. Also, predator leopard seals, which aren't very efficient hunters, are more interested in the bigger colonies, where they have a better chance to catch their nourishing penguin snack.
Along the way, penguin privacy has gone out the window: To keep track of a representative selection of individual penguins, Ainley has banded them on one of their flippers, making it easy to identify each from afar through binoculars. [Image Gallery: Private Sex Lives of Penguins]
Moreover, at the exit of the colonies, Ainley has mounted electronic weigh bridges, over which the penguins have to pass when they go foraging in the open sea, and again when they return to feed their newborn chicks from their own stomachs. Radio-frequency chips identify the penguins, and the automatic measurements provide a detailed record of their foraging and feeding behaviors during the austral summer season.
An icy obstacle
All was going well with Ainley's research. But in March 2000, catastrophe struck. A huge part of the Ross Ice Shelf broke loose. The iceberg, nearly the size of the state of Connecticut, blocked access to the open waters of the Ross Sea, effectively cutting off the penguins' preferred route to their winter habitat, farther away from the pole. To reach these slightly warmer and less gloomy regions with their fish and krill in tow, the poor birds now had to take a 50-mile (80 kilometers) detour. Eventually, the iceberg would remain stuck for a period of five years, and the penguin colonies diminished markedly. [Album: Stunning Photos of Antarctic Ice]
"At first, I was very disappointed," said Ainley, as it looked as if the iceberg had wrecked his research program. "But then it turned out that there was a lot of new information to gain from the whole episode." In particular, Ainley discovered many penguins from the small colony at Cape Royds did not return home at all in the summer season, but started a new life at one of the other two Adélie colonies at Ross Island — at Cape Crozier and Cape Bird.
This was completely unexpected, said Ainley. "The scientific gospel was that penguins live in the same colony for their entire life, and that they never migrate elsewhere. But the gospel was written by people who had never witnessed an iceberg event like this one."
Contemplating the universe
By now, everything is pretty much back to normal again. Together with his colleague Jean Pennycook, Ainley started his 17th field expedition in early December. Every other day at Cape Royds, he walks through the penguin colony, armed with a pair of binoculars, keeping track of what the birds are doing. "There's not very much to do, really,” he said. “Actually, I spend most of my time at my laptop." Research results, as well as daily pictures from breeding nests, are published at a special website, www.penguinscience.com, partly for educational reasons.
The small colony at Cape Royds has a population of about 2,000 penguin pairs, as opposed to Cape Bird, with some 50,000 pairs, and Cape Crozier, the biggest colony in the world, with a staggering 280,000 pairs. "At the other colonies, there's more than enough work to keep two people busy for seven days a week," he said.
But despite the cold, Ainley doesn't seem to mind the relative lack of work. Pointing at the male penguins that are solemnly breeding two fresh-laid eggs each, he notes: "They're just sitting there, contemplating the universe."
To many researchers in Antarctica, the combination of utter remoteness and overwhelming natural beauty is the main atttraction of the frozen continent. In fact, Ainley admits he choose penguin research for his doctoral work just to get a chance to go to Antarctica. "I just had to go there," he said. "I could've chosen geology instead, since I also majored in that discipline."
Then again, monitoring the full life cycle of a mountain or a glacier, from birth to death, is a bit beyond human scope. In the case of the Adélie penguins, Ainley almost accomplished this feat. "I'll return two more times on my current grant," he said. "If I'm creative enough to come up with a new research project, I may receive another five-year grant."
The penguins aren't likely to mind. Who knows, they might start to miss their human friend if he weren't to show up anymore.
Dutch freelance science writer Govert Schilling visited McMurdo Station and the Amundsen-Scott South Pole Station in early December as a selected member of the National Science Foundation's Antarctic media visit program.
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