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
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MCMURDO SOUND, Antarctica
— 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
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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