<h1>Melting sea ice threatens emperor penguins, study finds (w/ Video)</h1><h2><p><small><a class="textTag" href="http://phys.org/archive/20-06-2012/"><font>June 20, 2012</font></a><font> </font></small></p></h2><h2><a href="http://phys.org/news/2012-06-sea-ice-threatens-emperor-penguins.html">http://phys.org/news/2012-06-sea-ice-threatens-emperor-penguins.html</a></h2>
<h2>--------------------</h2><h2><a href="http://www.whoi.edu/page.do?pid=50242&tid=3622&cid=141592">http://www.whoi.edu/page.do?pid=50242&tid=3622&cid=141592</a></h2><h2>Melting Sea Ice Threatens Emperor Penguins, Study Finds</h2>
<div class="news-release"><p><strong>FOR IMMEDIATE RELEASE</strong></p><div>
<p>Media Relations Office</p>
<p><a href="mailto:media@whoi.edu">media@whoi.edu</a></p>
</div>
<p>June 20, 2012</p>
<p>(508) 289-3340</p></div>
<p>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<strong> </strong>Terre Adélie, in East Antarctica<strong> </strong>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 <em>Global Change Biology.</em></p>
<p>“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 sea ice due to warming temperatures in
the region.</p>
<p>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.</p>
<p>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.</p>
<p>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 Antarctica where French scientists have conducted
penguin observations for more than 50 years.</p>
<p>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.</p>
<p>“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.”</p>
<p>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.</p>
<p>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.”</p>
<p>Jenouvrier used the output from these various climate models to
determine how changes in temperature and sea ice might affect the
Emperor penguin 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.</p>
<p>“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.</p>
<p>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.</p>
<p><strong></strong>“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 penguins—is in our best interest,
because it helps us understand ecosystems that provide important
services to us."</p>
<p>Also collaborating on the study were Christophe Barbraud and Henri
Weimerskirch of the Centre d'Etudes Biologiques de Chizé, in France, and
Mark Serreze of the National Snow and Ice Data Center in the United
States.</p>
<p>Funding for the study was provided by the WHOI Ocean Life Institute,
Arctic Research Initiative, and Access to the Sea, the National Science
Foundation, REMIGE (Behavioral and demographic REsponses of Indian ocean
Marine top predators to Global Environmental changes) program, Agence
National de la Recherche Biodiversité, Zone Atelier de Receherches sur
l’Environment Antarctique et Subantarctique, the Institut Paul Emilie
Victor (IPEV), Alexander von Humboldt Foundation, Marie-Curie European
fellowship, and the Cooperative Institute for Research in Environmental
Sciences visiting fellowship.</p>
<p><em>The Woods Hole Oceanographic Institution is a private, non-profit
organization on Cape Cod, Mass., dedicated to marine research,
engineering, and higher education. Established in 1930 on a
recommendation from the National Academy of Sciences, its primary
mission is to understand the oceans and their interaction with the Earth
as a whole, and to communicate a basic understanding of the oceans’
role in the changing global environment. For more information, please
visit <a href="http://www.whoi.edu">www.whoi.edu</a>.</em></p><div class="date"><p>Originally published: June 20, 2012</p><p>--------------------------------------</p><p>Vision2020 Post Ted Moffett</p></div>