• Penguins have flightless wings, all the better to swim with, my dear

    Michael Bulhozer / Reuters

    A king penguin swims in a pool at the zoo in Zurich August 15, 2012.

    By Nidhi Subbaraman

    Penguins have evolved into champion divers and graceful swimmers, but somewhere along the way, they lost the ability to fly. It now looks like birds are built to do one or the other — fly or swim. Penguin ancestors chose one path a long time ago and just stuck to it. 

    "To be an efficient swimmer you want a wing that is more like an oar — that makes it impossible to fly," Robert Ricklefs, professor of biology at the University of Missouri, told NBC News. A penguin wing designed to shove aside water, shortened for diving and swimming, comes with a price-tag: terminal inefficiency of flight. 

    By studying two bird species which can both dive and swim, Ricklefs and an international group of researchers are adding evidence to the theory that penguins sacrificed the ability to fly so they could move better under water.

    Kyle H. Elliot

    Murres are the most inefficient flying birds of all.

    The researchers studied murres, which roost in cliffs overlooking Arctic waters, and cormorants. Because both species are small, their wings can carry them through the air and in the sea, but bigger birds can't pull that off, the authors explain in Monday's edition of the Proceedings of the National Academy of Sciences. 

    Penguins have been studied aplenty. But diving fliers like the murres or cormorants haven't made the leap into flightlessness, are "getting closer to the lifestyle of a penguin," and could provide clues to how penguins got where they are now, Ricklefs says. 

    The group studied 41 murres roosting on the cliff-faces of Nanavuk, Canada and 22 cormorants, dwellers of Middleton Island, Alaska, for a few weeks each. They recorded energy efficiencies as the birds swam and dived and flew. The diving swimmers were just-okay fliers — and they took wing, the murres were the most energetically inefficient fliers of any known flying vertebrate. 

    The authors argue that penguins took that tradeoff one step further: they lost all ability to fly, but padded their bodies with muscles that would increase the power in their wingstrokes when they swam. "There aren't many flying things that are the weight of large penguins," Ricklefs said. The larger, now extinct cousins of the murres and cormorants were also flightless. 

    More about penguins: 

    In addition to Robert Ricklefs, the authors of High flight costs, but low dive costs, in auks support the biomechanical hypothesis for flightlessness in penguins include Kyle Elliott, Anthony Gaston, Scott Hatch, John Speakmane and Gail K. Davoren.

    Nidhi Subbaraman writes about science and technology. Follow her on Facebook, Twitter and Google+.

  • Humans visit and confirm existence of penguin colony

    International Polar Foundation

    The newly discovered 9,000-strong emperor penguin colony on the East Antarctic coast.

     

    By Douglas Main
    Our Amazinig Planet

    The existence of a 9,000-strong colony of emperor penguins in East Antarctica has been confirmed by three people who visited it for the first time.

    Signs of the penguins were spotted by satellite, which took images of large stains on the snow in 2009 that scientists suspected were penguin feces. But it wasn't until early December 2012 that three people from Belgium's Princess Elisabeth Antarctica polar research station visited the colony to glimpse the penguins for themselves, according to a statement from the International Polar Foundation, which runs the station.

    The first three visitors were the station's expedition leader Alain Hubert, mechanic Kristof Soete and Swiss mountain guide Raphael Richard.

    The explorers decided not to chance a trip to the suspected colony earlier due to bad weather. But in early December the weather let up, and they arrived at the colony in the dead of night.

    "It was almost midnight when we succeeded in finding a way down to the ice through crevasses and approached the first of five groups of more than a thousand individuals, three quarters of which were chicks," said Hubert in the statement. "This was (an) unforgettable moment!" [ See photos of the penguin colony.]

    The trio was part of a team supporting scientific research on the Derwael Ice Rise, about 30 miles (50 kilometers) from the colony. Here, researchers are looking to see how quickly ice from the East Antarctic Ice Sheet is being lost to the sea due to warming-fueled melt.

    International Polar Foundation

    Some of the elegant occupants of the colony that was confirmed in East Antarctica.

    Scientists estimate the population of emperor penguins of Antarctica is larger than once thought; satellite imagery has helped to find previously unknown colonies like this one, by pinpointing stains from penguin feces as well as spotting the penguins themselves.

    Nevertheless, the fate of these and other penguins remains uncertain, and penguin numbers are likely to decline if the continent continues to warm.

    The Antarctic Peninsula, where emperor penguins are plentiful, is one of the fastest-warming places on Earth, with air temperatures rising between 4 and 4.5 degrees Fahrenheit (2.2 and 2.5 degrees Celsius) in the last 50 years.

    Emperor penguins are the largest penguin species and stand on average about 45 inches (114 centimeters) tall  and weigh 90 pounds (41 kilograms).

    Reach Douglas Main at dmain@techmedianetwork.com. Follow him on Twitter @Douglas_Main. Follow OurAmazingPlanet on Twitter @OAPlanet. We're also on Facebook and Google+.

  • Penguins' private lives recorded in Antarctica

    Sue & Wayne Trivelpiece

    A colony of Adélie penguins on the West Antarctic Peninsula.

    By Govert Schilling, LiveScience

    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.

    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

    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 ]

    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.

    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 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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