Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Emperor penguins threatened by Antarctic sea ice loss

21.06.2012
A decline in the population of emperor penguins appears likely this century as climate change reduces the extent of Antarctic sea ice, according to a detailed projection published this week.
The study, led by the Woods Hole Oceanographic Institution (WHOI), with co-authors from the National Center for Atmospheric Research (NCAR) and other organizations, focuses on a much-observed colony of emperor penguins in Terre Adélie, Antarctica. The authors conclude that the number of breeding pairs may fall by about 80 percent by 2100.

“The projected decreases in sea ice may fundamentally alter the Antarctic environment in ways that threaten this population of penguins,” says NCAR scientist Marika Holland, a co-author of the study.

The study uses a set of sophistical computer simulations of climate as well as a statistical model of penguin demographics. Building on previous work, it examines how the sea ice may vary at key times during the year such as during egg laying, incubation, rearing chicks, and non- breeding season, as well as the potential influence of sea ice concentrations on males and females.

The authors stress that their projections contain large uncertainties, because of the difficulties in projecting both climate change and the response of penguins. However, almost all of their computer simulations pointed to a significant decline in the colony at Terre Adélie, a coastal region of Antarctica where French scientists have conducted penguin observations for more than 50 years.

“Our best projections show roughly 500 to 600 breeding pairs remaining by the year 2100,” says lead author Stéphanie Jenouvrier, a WHOI biologist. “Today, the population size is around 3,000 breeding pairs.”

She noted that another penguin population, the Dion Islets penguin colony close to the West Antarctic Peninsula, has disappeared, possibly because of a decline in Antarctic sea ice.

The new research represents a major collaboration between biologists and climate scientists to assess the potential impacts of climate change on a much-studied species.

Published this week in the journal Global Change Biology, the study was funded in part by the National Science Foundation, NCAR’s sponsor. Other funders include WHOI; the French National Agency for Research (ANR) program on biodiversity; the ANR REMIGE program (Behavioral and Demographic Responses of Indian Ocean Marine Top Predators to Global Environmental Changes); the Zone Research Workshop for the Antarctic and Subantarctic Environment (ZATA); the Paul Emilie Victor Institute (IPEV); Alexander von Humboldt Foundation; Marie-Curie European Fellowship; and the U.S. Cooperative Institute for Research in Environmental Sciences visiting fellowship.

Vulnerable emperors of the ice

At nearly four feet tall, emperors are the largest species of penguin. They are vulnerable to changes in sea ice, where they breed and raise their young almost exclusively. If that ice breaks up and disappears early in the breeding season, massive breeding failure may occur, Jenouvrier says.

Disappearing sea ice may also affect the penguins’ food sources. They feed primarily on fish, squid, and krill, a shrimplike animal that feeds on zooplankton and phytoplankton that grow on the underside of 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 the extent of sea ice in the region will change this century, Holland and another co-author, Julienne Stroeve, a sea ice specialist from the National Snow and Ice Data Center, evaluated 20 of the world’s leading computer-based climate models. They selected the five models that most closely reproduced changes in actual Antarctic sea ice cover during the 20th century.

“When a computer simulation performs well in reproducing past climate conditions, that suggests its projections of future climate conditions are more reliable,” Holland says.

The team evaluated simulations from each of the 20 climate models. The simulations were based on a scenario of moderate growth in greenhouse gas emissions during this century. The moderate growth scenario portrays future reliance by society on a combination of greenhouse-gas emitting fossil fuels as well as renewable energy sources.

The simulations showed a decline in sea ice coverage across a large region by Terre Adélie at key times in the penguin breeding cycle, although they differed in the details.

Jenouvrier used the output from the climate models to determine how changes in temperature and sea ice might affect the emperor penguin population at Terre Adélie, studying such details as how the sea ice was likely to vary during breeding season and how it could affect chicks, breeding pairs, and non-breeding adults. She found that if global temperatures continue to rise at their current rate—causing sea ice in the region to shrink—penguin population numbers most likely 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.

The authors say that more research is needed to determine whether emperor penguins may be able to adapt to changing conditions or disperse to regions where the sea ice is more habitable.

Human reliance on the Antarctic

Rising temperature in the Antarctic isn’t just a penguin problem, according to Hal Caswell, a senior mathematical biologist at WHOI and collaborator on the study. 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,” he says. “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."

Also co-authoring 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.

About the article

Title: Effects of climate change on an emperor penguin population: analysis of coupled demographic and climate models

Authors: Stéphanie Jenouvrier, Marika Holland, Julienne Stroeve, Christophe Barbraud, Henri Weimerskirch, Mark Serreze, and Hal Caswell

Journal: Global Change Biology
*Media & nonprofit use of images: Except where otherwise indicated, media and nonprofit use permitted with credit as indicated above and compliance with UCAR's terms of use. Find more images in the UCAR Digital Image Library.

The University Corporation for Atmospheric Research manages the National Center for Atmospheric Research under sponsorship by the National Science Foundation. Any opinions, findings and conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

David Hosansky | EurekAlert!
Further information:
http://www.ucar.edu

More articles from Life Sciences:

nachricht Bolstering fat cells offers potential new leukemia treatment
17.10.2017 | McMaster University

nachricht Ocean atmosphere rife with microbes
17.10.2017 | King Abdullah University of Science & Technology (KAUST)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>