Facts About Polar Bears

Polar bear populations are declining.
The number of polar bear populations that are declining has increased. In 2005, a group of scientists and managers from five Arctic nations unanimously concluded that two of Canada’s 13 populations were depleted and five were declining. This is in contrast to a 2001 assessment that only one to two populations were in decline.

In the Western Hudson Bay, published peer-reviewed studies show that the population declines and other changes - such as reduced weight, decreased reproductive success, and decreased size - are clearly linked to the decline in sea ice.

Since 2002, many polar bear populations in Alaska have shown increasing signs of stress, including drownings, malnutrition, and cannibalism. The U.S. Geological Survey estimates that all polar bears in Alaska may be extinct as early as 2050.

The best available science shows that polar bears are facing extinction due to the loss of their sea ice habitat.
The U.S. Fish and Wildlife has concluded that polar bears are threatened with extinction, based on the best available science as required by the Endangered Species Act. The agency reached this conclusion based not only on the well-documented, severe decline of the Western Hudson Bay population -- which is directly linked to the early break-up and loss of seasonal sea ice -- but on other empirical, peer-reviewed, scientific studies demonstrating changes in denning behavior and prey availability. This finding was also based on well-documented, and often unusual, incidences of polar bear drowning, cannibalism, and malnourishment. Finally, modeling has long been used in making population forecasts for wildlife, and the climate models used by the U.S. Fish and Wildlife Service and the U.S. Geological Survey are robust and generally accepted within the scientific community.

In addition, the majority of climate models have, to date, underestimated the actual observed sea ice loss. In fact, the 2007 record low sea ice extent is far below that predicted by any of the 10 climate models used by the USGS. Therefore, the assessment of risk to the polar bear is actually conservative.

Global warming will harm biodiversity in the Arctic.
There is overwhelming scientific evidence that warming temperatures not only will lead to the extinction of the polar bear, but will affect other ice-dependent species in the Arctic and lead to widespread and highly disruptive shifts in the entire Arctic ecosystem.

Federal protection for polar bears would not affect subsistence hunting.
Some indigenous peoples in Canada have expressed concern that protecting polar bears under the Endangered Species Act could limit subsistence hunting. This is not the case. The Endangered Species Act contains an explicit exception for subsistence hunting.

Polar bear protection is not a substitute for global warming legislation.
Protection of the polar bear under the Endangered Species Act would require federal agencies to “consult” with the U.S. Fish and Wildlife Service before proceeding with industrial development and other actions that may cause harm to the species. While endangered species protection could result in additional consideration for proposed sources of global warming pollution, and would provide agencies with an important new lens through which to assess global warming pollution, dramatic cutbacks in this pollution can only be achieved through the passage of national global warming legislation.

   

The Polar Bears Need Our Help…and Fast…Help Stop the Melt

Without federal protection, the polar bear could become the first mammal to lose 100 percent of its habitat to global warming. Global warming is the leading threat to our planet as a whole.  A rise in global temperature of one degree Fahrenheit has already caused the polar ice cap to shrink, malaria and other illnesses to afflict more people, and heat waves, wildfires, droughts, and hurricanes to intensify.  Allowing temperatures to rise more than another 2 degrees Fahrenheit threatens to trigger the irreversible melting of the Greenland ice sheet, a 20-foot rise in sea levels, and the extinction of species, including the polar bear. 

• Polar bears, the world's strongest swimmers, are being forced to swim further and further to ever-distant ice flows. Four were found drowned in the Bering Strait.
• Newborn cubs were crushed to death when their snowy dens collapsed from unseasonable rains.
• More than 25 percent of the world's polar bear populations are already in decline.
• The polar bear is considered a marine mammal -- like walruses, seals and whales -- because its main habitat is sea ice.
• The arctic may be virtually free of summer sea ice by 2040 -- and without sea ice, polar bears cannot survive.
• As sea ice decreases, polar bear females may not gain enough weight to reproduce cubs with enough insulating fat -- jeopardizing their ability to survive.

May 2008
While there are an estimated 20,000 to 25,000 polar bears now in the Arctic, scientists from the U.S. Geological Survey predict two thirds of the world's polar bears will disappear in the next 50 years because of a decline in Arctic sea ice.

Controversy over the status of the polar bear is tied to the fact that this is the first time a species has been considered for listing specifically because its habitat is threatened by global warming.

"This decision is a watershed event because it has forced the Bush administration to acknowledge global warming's brutal impacts," said Kassie Siegel, climate program director at the Center for Biological Diversity.

The Center for Biological Diversity was one of three environmental groups, including Greenpeace and the Natural Resources Defense Council, which sued the federal government to force a decision on the status of the polar bears.

"The polar bear is a compelling symbol. What is happening to the polar bear is happening to the Arctic. And it's happening more rapidly and more severely than anywhere in the world. It is a signal we are in deep trouble, that we need to take action on climate change", said Margaret Williams, managing director of the Kamchatka-Bering Sea Ecoregion for the World Wildlife Fund U.S.

Western Antarctic Ice Chunk Collapses

March 2008

Washington- A chunk of Antarctic ice about seven times the size of Manhattan suddenly collapsed, putting an even greater portion of glacial ice at risk, scientists said Tuesday. 

Satellite images show the runaway disintegration of a 160-square-mile chunk in western Antarctica, which started Feb. 28. It was the edge of the Wilkins ice shelf and has been there for hundreds, maybe 1,500 years.

This is the result of global warming, said British Antarctic Survey scientist David Vaughan. Because scientists noticed satellite images within hours, they diverted satellite cameras and even flew an airplane over the ongoing collapse for rare pictures and video.  "It's an event we don't get to see very often," said Ted Scambos, lead scientist at the National Snow and Ice Data Center in Boulder, Colo. "The cracks fill with water and slice off and topple... That gets to be a runaway situation."

While icebergs naturally break away from the mainland, collapses like this are unusual but are happening more frequently in recent decades, Vaughan said. The collapse is similar to what happens to hardened glass when it is smashed with a hammer, he said.  The rest of the Wilkins ice shelf, which is about the size of Connecticut, is holding on by a narrow beam of thin ice. Scientists worry that it too may collapse. Larger, more dramatic ice collapses occurred in 2002 and 1995.

Vaughan had predicted the Wilkins shelf would collapse about 15 years from now. The part that recently gave way makes up about 4 percent of the overall shelf, but it's an important part that can trigger further collapse.  There's still a chance the rest of the ice shelf will survive until next year because this is the end of the Antarctic summer and colder weather is setting in, Vaughan said.

Scientists said they are not concerned about a rise in sea level from the latest event, but say it's a sign of worsening global warming.  Such occurrences are "more indicative of a tipping point or trigger in the climate system," said Sarah Das, a scientist at the Woods Hole Oceanographic Institute.  "These are things that are not re-forming," Das said. "So once they're gone, they're gone."

Climate in Antarctica is complicated and more isolated from the rest of the world.  Much of the continent is not warming and some parts are even cooling, Vaughan said. However, the western peninsula, which includes the Wilkins ice shelf, juts out into the ocean and is warming. This is the part of the continent where scientists are most concern about ice-melt triggering sea level rise.