Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Polar bear headed for extinction, says University of Alberta scientist

08.01.2003


Unless the pace of global warming is abated, polar bears could disappear within 100 years, says a University of Alberta expert in Arctic ecosystems.



While it has been known for some time that the polar bear is in trouble, new research shows that Arctic ice--the polar bear’s primary habitat--is melting much faster than scientists had believed, says U of A biologist Dr. Andrew Derocher.

"The climate predictions coming out are showing massive changes in sea-ice distribution," said Derocher, who follows polar bears to see how they adapt to changing conditions. If the predictions are correct, he says, "we’ll certainly lose polar bears in a lot of areas where we currently have them." Ice conditions in the Beaufort Sea, for example, are already changing dramatically.


The world’s largest terrestrial carnivores, polar bears rely on sea ice to survive, using it to pass between forest dens and hunting grounds where they prey on seals. There are about 15,000 polar bears in northern Canada, accounting for about two-thirds of the world’s total population.

Derocher shared his views Jan. 6 at a symposium on Arctic biology in Toronto. It was the biggest gathering of Canadian Arctic biologists in more than a decade, says co-chair Dr. David Hik, also of the U of A. Many of the talks addressed the impact of climate change on northern ecosystems.

Derocher says if global warming continues unchecked, some remnant populations of polar bears may manage to hang on in the high Canadian archipelago or on permanent polar ice at very high latitudes. But the potential for extinction is still a cause for concern: "You don’t have to be a polar scientist to see that if you take away all the sea ice, you don’t have polar bears any more."

To make matters worse, sea-ice melting is accelerated by "positive feedback loops." Sea ice acts as a reflector of solar energy, but when the ice disappears, the ocean absorbs that heat energy, which in turn prevents ice from freezing.

"Once climate warming initiates, you get into a self-warming cycle," said Derocher, who earned international renown as a polar bear and northern studies expert at the Norwegian Polar Institute in Tromso before returning to the University of Alberta, where he completed his doctorate. "That’s why the urgency on the issue for polar bears now."

He adds that it is possible a warmer climate will improve polar bear and seal habitats in the short term, mainly in higher latitudes where ice is too thick for seal hunting. But these areas are small, he says, and will only support a fraction of the bear population.

Polar bears can tolerate some environmental variation from year to year, foregoing reproduction in any given year if conditions are poor." With too much variation, however, reproduction will fall off dramatically, and populations will quickly decline. Scientists have no evidence yet of a drop in polar bear populations, but body weights and reproductive rates of bears in the Hudson Bay are on the decline," said Derocher.

Hik says there is also new research looking at the harmful effect of drought-related forest fires on polar bear dens, which are built in mature forests.

"When you burn the forest down, it blackens the earth, and these dens burrowed into the permafrost collapse," said Hik. "Many of them are created over centuries by successive generations of bears scraping deeper and deeper in." The area around Churchill, Manitoba is one such area that has been losing these dens.


The U of A in Edmonton, Alberta is one of Canada’s premier teaching and research universities serving more than 30,000 students with 6,000 faculty and staff. It continues to lead the country with the most 3M Teaching Fellows, Canada’s only national award recognizing teaching excellence.

Phoebe Dey | EurekAlert!
Further information:
http://www.ualberta.ca/

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Designer cells: artificial enzyme can activate a gene switch

22.05.2018 | Life Sciences

PR of MCC: Carbon removal from atmosphere unavoidable for 1.5 degree target

22.05.2018 | Earth Sciences

Achema 2018: New camera system monitors distillation and helps save energy

22.05.2018 | Trade Fair News

VideoLinks
Science & Research
Overview of more VideoLinks >>>