CBS News Sunday Morning Correspondent Jerry Bowen reports from the home of hundreds of thousands of Adelie penguins. For millions of years the birds have mated here, evolving into a sophisticated society - until now. Adelie penguins are suddenly being caught in a struggle for survival.
Nearly every year, David Ainley goes where few humans have been; a tiny corner of Antarctica called Cape Crozier, home to the world's largest concentration of Adelie penguins.
There you can find a half million of penguins on a three-mile stretch of coastline. Each one looks like a haberdasher's dream come true in black and white, in wingtips and tails.
"Maybe this is Adelie penguin heaven around here," says Ainley. "If you're an Adelie penguin, this is really the part of the world where you want to be." Or it used to be. This year Ainley discovered something disturbing.
"I've noticed something that I've never known to occur here, and that is there's a whole segment of what should have been breeding birds that did not breed this year."
The birth rate recently plunged 70 percent at Cape Crozier. But the clue may lie just offshore. Where there should be miles of pack ice there is only open water.
"Ice to the Adelie penguin is like trees to a songbird," explains Ainley. "If you chop down all the trees, then the songbirds will go away. If you lose pack ice in the southern ocean, then you lose the Adelie penguin."
"It's good to have a world with penguins in it," he says.
And so does Connie Adams, one of Ainley's researchers working 100 miles up the coast at Cape Royds.
"I consider it an incredible joy every day to come down here," she says. "We're among penguins! And I leave here every day with this incredible joy inside of me."
The Cape Royds penguins may also be in trouble, just like the ones at Cape Crozier. They, too, are experiencing unusually hot weather.
"For the chicks, it's too warm," says Adams pointing to penguins splayed out to keep cool. "They're trying to lose heat through their feet! Their feet are in back and their wings are stretched out and they're panting!"
In some ways the birds are very much like us. They work very hard, commuting long distances, swimming up to 50 miles a day to bring home the bacon (the shrimp they feed to their chicks). And like us, they are vulnerable to the weather, especially susceptible to climate change.
While climatic change is a politically charged issue, it's a matter of record that the earth has been slowly warming for a full century. In parts of Antarctica, temperatures have increased by 5 degrees Fahrenheit over the last 50 years. In those regions, Adelie penguin colonies have vanished.
Even in the best of times, life for an Adelie penguin is a struggle. Start with a hopeful male trying to attract the attention of a willing mate over the sounds of thousands of others. The bid builds a sturdy nest to woo a mate. Rocks and pebbles keep the eggs off the wet ground. And in the penguin world, where bigger is also better, neighbors constantly rob each other to make home improvements.
Once the couple produces a chick, their life becomes a nonstop effort to keep the youngster full and happy. Think of it like feeding a teenager. And coming up with meals has just become more difficult.
The sea ice harbors tiny shrimp known as krill, the penguin's main food source. Less ice means the birds must swim greater distances to find the krill. It also means less for their chicks. With the parents gone longer, the chicks are more exposed to scavengers like the skua, a sea bird that quickly makes meals of eggs and chicks alike.
This is part of the natural order of things, says researcher Ian Gaffney. "It tends to teach you about life and death on a more massive scale than you are familiar with as a human," he says. "And it's part of the ebb and flow you have down here in Antarctica."
"These birds are sort of the ultimate little denizens of this environment," says Gaffney.
One need only travel to Robert Falcon Scott's hut at nearby Cape Evans to realize penguins have been studied since the first explorers' arrival on the continent. Scott's hut served as a staging area for his ill-fated 1911 expedition to the South Pole. At Scott's hut everything is perfectly preserved, freeze-dried, including an emperor penguin.
Back then, penguins were regarded both as a biological curiosity and emergency cuisine. Running after the birds was considered a harmless diversion. This is documented in a rare film, made at Scott's hut in 1911, and in another 1928 film of Admiral Richard Byrd's crew herding the birds with sled dogs and teasing them with hand puppets.
Harassment of wildlife is now banned on the continent. These days a kinder, gentler science is practiced. "We're actually getting information about the comings and goings of the birds," says researcher Denise Hardesty, who operates a computerized monitoring station connected to a small bridge that weighs birds leaving the nest and upon their return from the sea with food.
Each parent inside a particular fence has been implanted with a bar-code capsule, like the marking on a grocery product, so they can be tracked. Their weight records reveal how far they must swim to find sea ice and food. This is one more indicator of the penguin's changing environment - as well as our own.
Antarctica is recognized as the Earth's thermostat, churning out cold winds and waters that influence temperatures worldwide. It is the place scientists scan for an early warning of changes in a climate that is getting warmer. What is happening to the Adelie penguins will tell part of the story.
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