Is Global Warming Killing the Polar Bears?

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Is Global Warming Killing the Polar Bears?

By JIM CARLTON

Staff Reporter of THE WALL STREET JOURNAL

December 14, 2005; Page B1

 

It may be the latest evidence of global warming: Polar

bears are drowning.

 

Scientists for the first time have documented multiple

deaths of polar bears off Alaska, where they likely

drowned after swimming long distances in the ocean

amid the melting of the Arctic ice shelf. The bears

spend most of their time hunting and raising their

young on ice floes.

 

In a quarter-century of aerial surveys of the Alaskan

coastline before 2004, researchers from the U.S.

Minerals Management Service said they typically

spotted a lone polar bear swimming in the ocean far

from ice about once every two years. Polar-bear

drownings were so rare that they have never been

documented in the surveys.

 

But in September 2004, when the polar ice cap had

retreated a record 160 miles north of the northern

coast of Alaska, researchers counted 10 polar bears

swimming as far as 60 miles offshore. Polar bears can

swim long distances but have evolved to mainly swim

between sheets of ice, scientists say.

[polar bear]

Polar bears in Alaska face melting ice floes.

 

 

 

The researchers returned to the vicinity a few days

after a fierce storm and found four dead bears

floating in the water. " Extrapolation of survey data

suggests that on the order of 40 bears may have been

swimming and that many of those probably drowned as a

result of rough seas caused by high winds, " the

researchers say in a report set to be released today.

 

While the government researchers won't speculate on

why a climate change is taking place in the Arctic,

environmentalists unconnected to the survey say U.S.

policies emphasizing oil and gas development are

exacerbating global warming, which is accelerating the

melting of the ice. " For anyone who has wondered how

global warming and reduced sea ice will affect polar

bears, the answer is simple -- they die, " said Richard

Steiner, a marine-biology professor at the University

of Alaska.

 

The environmental group Greenpeace began airing a

30-second commercial yesterday in New York, Los

Angeles, Atlanta and other cities showing an animated

adult polar bear and a cub on a cracking ice floe. The

two bears, nowhere near land, slip underneath the

water. " Polar bears may soon be extinct because of

global warming, " the voice-over states. It ends with

" Global Warming: It's the Real Thing, " a takeoff of a

Coca-Cola Co. commercial featuring polar bears.

 

Some experts say that climate change may indeed be

shrinking the ice pack, but they dispute that

emissions are the main culprit or that significantly

cutting greenhouse gases would really make a

difference. " Whether humans are responsible for some,

most, or all of the current warming trend in the

Arctic, there is no proposal on the table that would

actually prevent continued warming or reverse present

trends, " said Sterling Burnett, a senior fellow at the

National Center for Policy Analysis, a nongovernment

organization based in Dallas. " The question is how to

adapt to future changes in climate, regardless of the

direction or the cause. "

 

In addition to documenting polar-bear deaths, the

Minerals Management Service researchers, Chuck

Monnett, Jeffrey Gleason and Lisa Rotterman, also

found a striking shift in the bears' habits. From 1979

to 1991, 87% of the bears spotted were found mostly on

sea ice. From 1992 to 2004, the percentage dropped to

33%. Most of the remaining bears have been found

either in the ocean or on beaches, congregating around

carcasses of whales butchered by hunters. In the past,

polar bears were rarely seen at such kill sites,

because they spent their time hunting their favorite

meal -- seals -- on sea ice.

[Global Warming ad]

A Greenpeace commercial parodies a Coke ad.

 

 

 

Marine experts consider the findings -- to be

presented at a marine-mammal conference this week in

San Diego -- an ominous sign. Some have warned for

years that a rapid thawing of the Arctic from global

warming could endanger species like the polar bear.

Already, a warmer Alaska over the past half-century

has been linked to increased erosion of rivers and

streams, insect infestations and the undermining of

pipelines and roads as the permafrost thaws.

 

Alarmed by the swift changes, the Alaska Inter-Tribal

Council, a consortium of the state's tribes, earlier

this month passed a resolution urging that the U.S.

government enact a mandatory program to reduce global

warming.

 

Some scientists predict polar bears could become

extinct within the next century because they have

adapted over the millennia to only hunting on ice. If

they try to swim in disappearing ice conditions to

catch seals, more are likely to tire and drown,

scientists say. Polar bears that stay onshore aren't

adapted to hunting land animals like caribou, which

are preyed upon by more-aggressive grizzly bears.

Polar bears also require more fat intake than most

food on land offers them, experts say.

 

" As the sea ice goes, that will direct to a very great

extent what happens to polar bears, " said Steven

Amstrup, a polar-bear specialist with the U.S.

Geological Survey in Anchorage, Alaska.

 

Another study set to be released at the marine-mammal

conference shows what might happen to the Alaskan

polar bears over time. Researchers from the USGS, the

University of Wyoming and the Canadian Wildlife

Service found that the population of polar bears in

Canada's western Hudson Bay -- near the southernmost

habitat for the bears in the world -- fell to 935 in

2004 from 1,194 in 1987, a 22% drop. Researchers said

the decline -- the first recorded for these bears --

came in tandem with an extension by nearly a full

month in the time it takes for Hudson Bay to ice over

after the summer.

 

" Our findings may foreshadow how more northerly

populations will respond to projected warming in the

Arctic ecosystem, " wrote Mr. Amstrup, a co-author of

the report.

 

Previous studies by the U.S. and Canadian governments

support a link between the decline in sea ice in the

Arctic and the ways polar bears try to adapt to their

surroundings. For example, researchers say polar bears

in the Beaufort Sea off Alaska and Canada used to

spend most of their lives jumping from ice floe to ice

floe in pursuit of seals. Only pregnant bears would

occasionally wander onto the mainland, in search of a

den.

 

But weekly aerial surveys by the U.S. Fish and

Wildlife Service show that, over the past five years,

an unusually large number of bears have congregated

along the beaches. Between the coastal town of Barrow,

Alaska and the Canadian border, about 300 miles east,

researchers counted as many as 200 bears on land, said

Scott Schliebe, director of the Fish and Wildlife's

polar-bear project. Many bears could be seen gathered

around whale carcasses near villages like Kaktovik,

which lies in the Arctic National Wildlife Refuge

where the Bush administration is pushing for drilling.

 

Scientists measured the distances from where the bears

were gathered to the nearest ice sheets at sea and

found this correlation: The farther the ice was from

shore, the larger the number of bears were found on

land.

 

Scientists estimate there are 20,000 to 25,000 polar

bears world-wide, including about 2,000 that frequent

the Beaufort Sea off Alaska. The latest population

study by federal officials, in 1997, suggested the

Alaskan bear population wasn't endangered. An update

is expected by the end of next year.

 

Write to Jim Carlton at jim.carlton

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