Nine Polar Bears Make Risky, Open-Ocean Swims In One Day

Nine polar bears were observed in one day swimming in open ocean off Alaska's northwest coast, an increase from previous surveys that may indicate warming conditions are forcing bears to make riskier, long-distance swims to stable sea ice or land.

The bears were spotted in the Chukchi Sea on a flight by a federal marine contractor, Science Applications International Corp.

It was hired for the Minerals Management Service in advance of future offshore oil development. The MMS in February leased 2.76 million acres within an offshore area slightly smaller than Pennsylvania.

Observers Saturday were looking for whales but also recorded walrus and polar bears, said project director Janet Clark. Many were swimming north and ranged from 15 to 65 miles off shore, she said.

Department of Interior Secretary Dirk Kempthorne in May declared polar bears a threatened species because of an alarming loss of summer sea ice and forecasts the trend will continue.

Polar bears spend most of their lives on sea ice, which they use as a platform to hunt their primary prey, ringed seals. Shallow water over the continental shelf is the most biologically productive for seals, but pack ice in recent years has receded far beyond the shelf.

Conservation groups fear that one consequence of less ice will be more energy-sapping, long-distance swims by polar bears trying to reach feeding, mating or denning areas.

Steven Amstrup, senior polar bear scientist for the U.S. Geological Survey in Anchorage, said the bears could have been on a patch of ice that broke up northwest of Alaska's coast.

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"The bears that had been on that last bit of ice that remained over shallow shelf waters, are now swimming either toward land or toward the rest of the sea ice, which is a considerable distance north," he said in an e-mail response to questions.

It probably is not a big deal for a polar bear in good condition to swim 10 or 15 miles, Amstrup said, but swims of 50 to 100 miles could be exhausting.

"We have some observations of bears swimming into shore when the sea ice was not visible on the horizon," he said. "In some of these cases, the bears arrive so spent energetically, that they literally don't move for a couple days after hitting shore."

Only further research can tell the effect of greater swimming distances on polar bear populations, he said.

"Polar bears can swim quite well, but they are not aquatic animals," he said. "Their home is on the surface of the ice."

Satellite data Saturday showed the main body of pack ice about 400 miles offshore with one ribbon about 100 miles off Alaska's coast, said Mark Serreze of the National Snow and Ice Data Center.

Clark said the animals' origin and destination could not be known without radio collar monitoring.

"To go out there and say they were going from this point to this point would be complete speculation," Clark said.

Observers have no indication of the fate of the nine polar bears observed Saturday.

Comments

[yallerdog]

Polar bear aka Sea bear (Ursus maritimus).

[johnnyjust]

Greenland, people, Greenland.

Why was this land covered with ice so named?

I love "truthers," 9/11 or otherwise.

[mamacat]

The dynamic is that polar bears require an ice shelf in order to hunt seals, but they need the ice shelf to be near enough to land that they can raise their young. After a few years of the summer ice shelf being too far away from land for them to make the trip back and forth, we can expect the polar bear population to plummet. Not that I'm in love with Polar Bears, but the loss of one of the largest land mammals known seems like a shame. What do we have to look forward to? An earth where we can't even go outside unless we buy a ticket or win the lottery first? Oh, I know, let's drill more oil instead of developing alternative energy. Big Oil will get to make a few hundred Billion more dollars, and we will lose more species.

[judoka61]

And the saddest part of this story is that they will probably survive the ordeal of being left in the open ocean only to see themseves gunned down by us..

(google for : Iceland bear)

[loonylobo]

What about the mount hermon june beetle, the mission blue butterfly, the ohlone tiger beetle, the redwoods, the banana slugs, the (insert any specialized species here).....with reductions in biodiversity due to climate change (among other things such as invasive species, habitat degradation/destruction, etc. which have been happening for decades)...the world will be populated by ravens, raccoons and roaches within a short time. Polar Bears are great, but we need to not fixate on charismatic megafauna and start thinking about ecosystem functions and trophic structures.

[BassMent]

Global warming deniers are fond of pointing out historical evidence showing previous periods of "natural" warming throughout our planet's history. If species such as polar bears survived those periods, their argument goes, why should we be worried now?

There are at minimum two problems with this argument. The first is that the pace of the change in global temperature that we're experiencing now has rarely been seen in the past, and when it has, radical changes in species populations occurred. What would be the consequence for the human race if more than half of the known species on the planet died off relatively quickly, causing the collapse of entire ecosystems?

The bigger problem is that this is not the same planet that it was 115,000 years ago. We now have a human population that is rapidly approaching 7 billion. We are dependent upon a system of food production that is built around the reliability of the global climate within acceptable limits of variation. Variation outside of the acceptable limits will result in loss of food production capacity, and a consequent reduction through starvation of human population on an unprecedented scale (because the human population is unprecedented, not only in numbers, but in the ratio of our species to others, and the density of population on the land).

Whether a massive human die-out would be a good thing or a bad thing is open to debate. But it's foolishness to pretend that it can't happen.

[rivrgrrl]

A major die off of our species has happened before, I believe it was called something like the 'bottle neck' theory. Very early in our evolution. I'll have to re look that up now.

[ashabot]

When will we get it? When it's too late? This is a drastic, heartbreaking effect of human stupidity and waste.

[ilovemydoggy]

We're doomed. Don't read the ancient native American prophecies if you want to still sleep at night. When the Blue Kachina removes his mask, it is over. There is one ray of hope -- each prophecy says if man changes his ways, the Creator may give us a second change.

Baby boomer viewpoints: http://www.Vaboomer.com

[Ihaveadream]

The polar bears also have extremely high levels of all sorts of toxic chemicals in their bodies since the are at the top of the food chain. All of this is man made and very sad. For you nay-sayers, this is not a natural process - we caused it.

[WilliePilgrim]

Just for the interest of balance; the polar bears prey, ringed seals, feed on fish and crustaceans, wihch in turn feed on plankton which in turn thrive under the ice-free open waters of the north and should do very well for all organisms which are dependent on them. Furthermore, the reduction in ice means that the increased population of ringed seals will be concentrated in smaller areas making it easier for polar bears who are fortunate to be living in those areas to produce abundant offspring. Remember, the biggest threat to polar bears is not melting of ice, or hunting, but starvation...the ecosystem we have created in the northern oceans and seas is a vastly depleted one from the marine environment in which polar bears have adapted...rookeries, fisheries, haul-outs have all been hunted to within a hairs breath of total extinction. If all the ice came back tomorrow in some idealized fantasy world as it resides in the typical mindset of the the uninformed, the population of polar bears would still be imperilled. Forget about the CO2 levels...think about the barely functioning and out of balance ecosystems that are the result of the terribly short sighted resource management the humans have been imposing on these previously super-abundand and productive systems.

[RememberTheAlamo]

Nice!

[mamacat]

Polar Bears hunt the seals by waiting at holes where they come up to breathe. If there is nothing but open water, the Bears have no chance to catch the seals when they come up to breathe. There may be more seals in the open water, but how can the bears catch them?

[TrevorAlan]

Scientists are worried about the survival of polar bears due to global warming. So...

They get in gas-burning airplanes or highly inefficient helicopters, and fly around the bears swimming for their lives, possibly intimidating and disorienting them.

OK.

[rughead23]

eco, eco, ecol? ecol, econ?............................ecology

[VivaZapata]

Before rescue helicopters could reach George Bush and a team of greenhouse gas deniers whose plane went down while showing how safe drilling would prove for the environment, bands of hungry polar bears ate them. Unfortunately, the killer bears died from the poisoned food despite regurgitating the foul tasting flesh.

[LeftLeanWing]

Flesh ?....

Nothing but bone and gristle attacked to a 180 pound booger .

[rocksthedock]

This is a natural process that has occurred many times in the last 3 billion years. The primary impact initially felt on our planet will come as a result of a dramatic change in the ocean's currents; a change that will be felt soon. I would surmise that when new routes for currents open, as is happening due to melting ice sheets and cracks appearing in the arctic land masses, the change will be felt in years .. not thousands of years..

[realpolitic]

"Changes in the ocean and on land, including observed decreases
in snow cover and Northern Hemisphere sea ice extent, thinner sea
ice, shorter freezing seasons of lake and river ice, glacier melt, decreases
in permafrost extent, increases in soil temperatures and
borehole temperature profiles, and sea level rise, provide additional
evidence that the world is warming. {WGI 3.9}

Of the more than 29,000 observational data series, from 75 studies,
that show significant change in many physical and biological
systems, more than 89% are consistent with the direction of change
expected as a response to warming."

http://www.ipcc.ch/pdf/assessment-report/ar4/syr/ar4_syr.pdf

[huffposeur]

i'm no longer worried about polar bears. it is clear to me that as soon as o'bama is sworn in the number of polar bears will increase dramatically.

in fact, i feel certain that years from now, people will look back at his inauguration and say 'finally, the polar bears are safe.'

[realpolitic]

Do polar bears vote Democratic?

[enlighteninglad]

Of course. They are true blue environmentalists.

[WatchIt]

You clearly were home schooled, eh? Schooled in the home of Rush on the Radio...