Global Warming Center: Unhappy feet: Global warming and melting sea ice risk wiping out the ...

Wednesday, June 20, 2012

Unhappy feet: Global warming and melting sea ice risk wiping out the ... - Daily Mail

PUBLISHED: 07:59 EST, 20 June 2012 | UPDATED: 08:00 EST, 20 June 2012

Under threat: Global warming risks destroying the sea ice on which Emperor penguins raise their young

The Emperor penguin's future is looking bleak if global temperatures continue to rise and melt sea ice, scientists have warned.

At nearly four feet tall, Antarctica's largest sea bird became a global icon thanks to films like March of the Penguins and Happy Feet, but if temperatures continue to rise, it faces extinction.

Unlike other sea birds, Emperor penguins breed and raise their young almost exclusively on sea ice - if the ice breaks up and disappears early into the breeding season, massive breeding failure will occur.

There is already a huge death rate at the breeding stages because only half of chicks live to the end of the breeding season and then only half the survivors live to see another year.

The Dion Islet penguin colony had a thriving population of 250 breeding pairs in the 70s, but that number was reduced just 20 in 1999 and by 2009, it was wiped out entirely.

Researchers warn disappearing ice may also affect the fish, squid and krill that the penguins eat, which in turn feed on zooplankton and phytoplankton that grow on the ice.

If the ice goes, so will the plankton - causing a ripple effect through the food web that could starve the various species penguins rely on for food.

To work out how bleak the future is for penguins, researchers used various data, including climate models, sea ice forecasts and a demographic model created of the Emperor penguin population at Terre Adilie - a coastal region of Antarctica where French scientists have conducted penguin observations for more than 50 years.

Using climate models, they found if temperatures continue to rise at their current rate, causing sea ice to shrink, penguin numbers will diminish slowly until about 2040 - after which they will plunge at a much steeper rate.

At present, there are about 3,000 breeding pairs, but this could fall to roughly 500 to 600 by 2100.

According to researchers, rising temperatures are not just a penguin problem as the shrinking sea ice will result in changes in the Antarctic marine environment - affecting other species and possibly people.

Stephanie Jenouvrier said: 'Over the last century, we have already observed the disappearance of the Dion Islets penguin colony, close to the West Antarctic Peninsula.

'In the 1970s, scientists recorded more than 250 breeding pairs there. By 1999, the population was down to just 20 pairs, and in 2009, it had vanished entirely.'

Cute: At present, there are about 3,000 breeding pairs, but this could fall to roughly 500 to 600 by 2100, scientists warn

Hal Caswell said: 'If you want to study the effects of climate on a particular species, there are three pieces that you have to put together.

'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.

'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.

'Understanding the effects of climate change on predators at the top of marine food chains - like Emperor Penguins - is in our best interest, because it helps us understand ecosystems that provide important services to us.'

The findings are published in the journal Global Change Biology.