Melting sea ice threatens emperor penguins, study finds (w/ Video)

June 20, 2012, Woods Hole Oceanographic Institution
These are emperor penguins. Credit: Photo courtesy Glen Grant, US Antarctic Program, National Science Foundation.

At nearly four feet tall, the Emperor penguin is Antarctica's largest sea bird—and thanks to films like "March of the Penguins" and "Happy Feet," it's also one of the continent's most iconic. If global temperatures continue to rise, however, the Emperor penguins in Terre Adélie, in East Antarctica may eventually disappear, according to a new study by led by researchers from the Woods Hole Oceanographic Institution (WHOI). The study was published in the June 20th edition of the journal Global Change Biology.

"Over the last century, we have already observed the disappearance of the Dion Islets penguin colony, close to the West Antarctic Peninsula," says Stephanie Jenouvrier, WHOI biologist and lead author of the new study. "In 1948 and the 1970s, scientists recorded more than 150 breeding pairs there. By 1999, the population was down to just 20 pairs, and in 2009, it had vanished entirely." Like in Terre Adélie, Jenouvrier thinks the decline of those penguins might be connected to a simultaneous decline in Antarctic due to warming temperatures in the region.

Unlike other sea birds, Emperor penguins breed and raise their young almost exclusively on sea ice. If that ice breaks up and disappears early in the breeding season, massive breeding failure may occur, says Jenouvrier. "As it is, there's a huge mortality rate just at the breeding stages, because only 50 percent of chicks survive to the end of the breeding season, and then only half of those fledglings survive until the next year," she says.

Disappearing sea ice may also affect the penguins' food source. The birds feed primarily on fish, squid, and krill, a shrimplike animal, which in turn feeds on zooplankton and phytoplankton, tiny organisms that grow on the underside of the ice. If the ice goes, Jenouvrier says, so too will the plankton, causing a ripple effect through the food web that may starve the various species that penguins rely on as prey.

To project how penguin populations may fare in the future, Jenouvrier's team used data from several different sources, including climate models, sea ice forecasts, and a demographic model that Jenouvrier created of the Emperor penguin population at Terre Adélie, a coastal region of where French scientists have conducted penguin observations for more than 50 years.

This video is about emperor penguins and climate change. Credit: Woods Hole Oceanographic Institution

Combining this type of long-term population data with information on climate was key to the study, says Hal Caswell, a WHOI senior mathematical biologist and collaborator on the paper.

"If you want to study the effects of climate on a particular species, there are three pieces that you have to put together," he says. "The first is a description of the entire life cycle of the organism, and how individuals move through that life cycle. The second piece is how the cycle is affected by climate variables. And the crucial third piece is a prediction of what those variables may look like in the future, which involves collaboration with climate scientists."

Marika Holland of the National Center for Atmospheric Research is one such scientist. She specializes in studying the relationship between sea ice and global climate, and helped the team identify climate models for use in the study.

Working with Julienne Stroeve, another sea ice specialist from the National Snow and Ice Data Center, Holland ultimately recommended five distinct models. "We picked the models based on how well they calculated the sea ice cover for the 20th century," she says. "If a model predicted an outcome that matched what was actually observed, we felt it was likely that its projections of sea ice change in the future could be trusted."

Jenouvrier used the output from these various climate models to determine how changes in temperature and sea ice might affect the population at Terre Adélie. She found that if greenhouse gas emissions continue to rise at levels similar to today—causing temperatures to rise and Antarctic sea ice to shrink—penguin population numbers will diminish slowly until about 2040, after which they would decline at a much steeper rate as sea ice coverage drops below a usable threshold.

"Our best projections show roughly 500 to 600 breeding pairs remaining by the year 2100. Today, the population size is around 3000 breeding pairs," says Jenouvrier.

The effect of rising temperature in the Antarctic isn't just a penguin problem, according to Caswell. As sea ice coverage continues to shrink, the resulting changes in the Antarctic marine environment will affect other species, and may affect humans as well.

"We rely on the functioning of those ecosystems. We eat fish that come from the Antarctic. We rely on nutrient cycles that involve species in the oceans all over the world," he says. "Understanding the effects of climate change on predators at the top of marine food chains—like Emperor —is in our best interest, because it helps us understand ecosystems that provide important services to us."

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1.7 / 5 (6) Jun 20, 2012
@feldagast; fishy chicken!
3.9 / 5 (11) Jun 20, 2012
It's terrible situation in the vast Antarctic, with summer temperatures actually hitting 40F and some of the highest high temp recorded for the area for millions of years. The penguins are dying, sadly. All thanks to mankind and our creation of global warming from burning fossil fuels.

Sad to see for such a beautiful bird.
1.7 / 5 (11) Jun 20, 2012
"We present a population projection for the emperor penguin population of Terre Adelie, Antarctica, by linking demographic models (stage-structured, seasonal, nonlinear, two-sex matrix population models) to sea ice forecasts from an ensemble of IPCC climate models."

IPCC Climate Models have been repeatedly demonstrated to be crap.

No actual data was used in this piece of propaganda.

They used two flawed models to trawl for grant money.
4.1 / 5 (9) Jun 21, 2012

IPCC Climate Models have been repeatedly demonstrated to be crap.
Really? Not in a PropPer peer reviewed journal surely?

No actual data was used in this piece of propaganda.

Wait for it.......

They used two flawed models to trawl for grant money.

last i heard Models flawed or not counts as data.

I see Parker is not using the family braincell today!
2 / 5 (8) Jun 21, 2012

IPCC Climate Models have been repeatedly demonstrated to be crap.
Really? Not in a PropPer peer reviewed journal surely?

No actual data was used in this piece of propaganda.

Wait for it.......

They used two flawed models to trawl for grant money.

last i heard Models flawed or not counts as data.

I see Parker is not using the family braincell today!

Since when is a model real data?
4.3 / 5 (6) Jun 23, 2012
Ahhh, it is so pleasant to read Noparks (he hates parks btw) comments on such a cruel situation as the one mankind has placed on the Emperor Penguins. Noparks (he hates parks btw) always insists on data, on numbers that prove HIS points view without looking at them really. Really, Noparks don't you care about these penguins? Are they just model data?

Noparks, just go ahead an admit that your just one of the paid by the word ($0.05 per 6/letter word) Koch money pulpit. If that's not the case, what's your beef with the birds?

Iqbal Latif
1 / 5 (3) Jun 26, 2012
Nearly 600,000 emperor penguins have been recorded in Antarctica, almost double previous estimates, with satellite mapping technology.

This species breeds in remote, often inaccessible habitats where temperatures can drop down to -50 degrees Celsius and winds can reach 124 miles (200 km) per hour, making it difficult to study these giant birds and monitor any impacts of global warming.
The international study used Very High Resolution (VHR) satellite imagery of each colony along the continents coastline, fine-tuned by a process called pan-sharpening to improve the resolution and distinguish the birds from ice, shadow and guano (poo). Ground counts and aerial photos were used to check for accuracy.

We are delighted to be able to locate and identify such a large number of emperor penguins, said study lead author Peter Fretwell at British Antarctic Survey (BAS) in a press release.

'We counted 595,000 birds, which is almost double the previous estimates of 270,000 to 350,000 birds.'
5 / 5 (3) Jun 26, 2012
Latif; good try for a looser.

We counted 595,000 birds, which is almost double the previous estimates of 270,000 to 350,000 birds.

Sounds good an respectable for an industrial shill does it not?
First, what this article sites is the count at "Terre Adéliet", NOT the whole of the Antarctic. Second, if there are 595,000 birds on the Antarctic you should be concerned that the ecosystem is falling much more rapidly than what we conservatively have estimated.

Bottom-line; your full of yourself.

Iqbal Latif
1 / 5 (2) Jul 02, 2012
Everywhere you look, the "doomed" polar bear's story is illustrated with the classic photo of a mother and cub teetering on an fragile-looking ice floe, the ice full of holes and seemingly about to disappear into the sea.

"The drama is clear: This is truly the tip of an iceberg, the bears are desperately stranded as the water swells around them," according to a recent article in The Observer magazine carrying the photo.

For a species that can swim dozens of kilometres to find a decent seal dinner, a few hundred metres to shore is a leisurely doggie paddle to safety. So much for the optic of a doomed global warming victim on ice.

A new US Senate report says: The U.S. Fish & Wildlife Service estimates that the polar bear population is currently at 20,000 to 25,000 bears, up from as low as 5,000-10,000 bears in the 1950s and 1960s. Not only is the number of polar bears 5 times higher than it was 50 years ago, but the research of the most prestigious scientists is being suppressed.
1 / 5 (1) Jul 02, 2012
Polar Bear numbers are up over the 1960's because shotgun traps and auto-kill/maim traps were outlawed, and hunting restricted.

1,000 killed by hunters a year is not restricted.


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