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Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:04pm PT
The mind (my mind, anyway) boggles at trying to follow this exchange, but I gather that something or other is being claimed about polar bears? It's easy enough to check current research, e.g.

A tale of two polar bear populations: ice habitat, harvest, and body condition
Rode et al., Population Ecology (2011)

One of the primary mechanisms by which sea ice loss is expected to affect polar bears is via reduced body condition and growth resulting from reduced access to prey. To date, negative effects of sea ice loss have been documented for two of 19 recognized populations. Effects of sea ice loss on other polar bear populations that differ in harvest rate, population density, and/or feeding ecology have been assumed, but empirical support, especially quantitative data on population size, demography, and/or body condition spanning two or more decades, have been lacking. We examined trends in body condition metrics of captured bears and relationships with summertime ice concentration between 1977 and 2010 for the Baffin Bay (BB) and Davis Strait (DS) polar bear populations. Polar bears in these regions occupy areas with annual sea ice that has decreased markedly starting in the 1990s. Despite differences in harvest rate, population density, sea ice concentration, and prey base, polar bears in both populations exhibited positive relationships between body condition and summertime sea ice cover during the recent period of sea ice decline. Furthermore, females and cubs exhibited relationships with sea ice that were not apparent during the earlier period (19771990s) when sea ice loss did not occur. We suggest that declining body condition in BB may be a result of recent declines in sea ice habitat. In DS, high population density and/or sea ice loss, may be responsible for the declines in body condition.
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:07pm PT
Effects of climate warming on polar bears: a review of the evidence
Sterling & Derocher, Global Change Biology (2012)

Climate warming is causing unidirectional changes to annual patterns of sea ice distribution, structure, and freeze-up. We summarize evidence that documents how loss of sea ice, the primary habitat of polar bears (Ursus maritimus), negatively affects their long-term survival. To maintain viable subpopulations, polar bears depend on sea ice as a platform from which to hunt seals for long enough each year to accumulate sufficient energy (fat) to survive periods when seals are unavailable. Less time to access to prey, because of progressively earlier breakup in spring, when newly weaned ringed seal (Pusa hispida) young are available, results in longer periods of fasting, lower body condition, decreased access to denning areas, fewer and smaller cubs, lower survival of cubs as well as bears of other age classes and, finally, subpopulation decline toward eventual extirpation. The chronology of climate-driven changes will vary between subpopulations, with quantifiable negative effects being documented first in the more southerly subpopulations, such as those in Hudson Bay or the southern Beaufort Sea. As the bears' body condition declines, more seek alternate food resources so the frequency of conflicts between bears and humans increases. In the most northerly areas, thick multiyear ice, through which little light penetrates to stimulate biological growth on the underside, will be replaced by annual ice, which facilitates greater productivity and may create habitat more favorable to polar bears over continental shelf areas in the short term. If the climate continues to warm and eliminate sea ice as predicted, polar bears will largely disappear from the southern portions of their range by mid-century. They may persist in the northern Canadian Arctic Islands and northern Greenland for the foreseeable future, but their long-term viability, with a much reduced global population size in a remnant of their former range, is uncertain.
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:10pm PT
Credit: Ron Anderson
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:12pm PT
Importance of fast ice and glacier fronts for female polar bears and their cubs during spring in Svalbard, Norway
Freitas et al. Marine Ecology Progress Series (2012)

Arctic sea ice is declining rapidly, making it vital to understand the importance of different types of sea ice for ice-dependent species such as polar bears Ursus maritimus. In this study we used GPS telemetry (25 polar bear tracks obtained in Svalbard, Norway, during spring) and high-resolution synthetic aperture radar (SAR) sea-ice data to investigate fine-scale space use by female polar bears. Space use patterns differed according to reproductive state; females with cubs of the year (COYs) had smaller home ranges and used fast-ice areas more frequently than lone females. First-passage time (FPT) analysis revealed that females with COYs displayed significantly longer FPTs near (<10 km) glacier fronts than in other fast-ice areas; lone females also increased their FPTs in such areas, but they also frequently used drifting pack ice. These results clearly demonstrate the importance of fast-ice areas, in particular close to glacier fronts, especially for females with COYs. Access to abundant and predictable prey (ringed seal pups), energy conservation and reluctance to cross large open water areas are possible reasons for the observed patterns. However, glacier fronts are retracting in Svalbard, and declines in land-fast ice have been notable over the past decade. The eventual disappearance of these important habitats might become critical for the survival of polar bear cubs in Svalbard and other regions with similar habitat characteristics. Given the relatively small size of many fast-ice areas in Svalbard, the results observed in this study would not have been revealed using less accurate location data or lower-resolution sea-ice data.
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:12pm PT
Ron, what's the clue, in the first two words of your funnyman's graph, that it was not drawn by any scientist?
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:16pm PT
I could go ahead and post or repost biologists comments, or the Native peoples comments or any of the others ive already posted.


but to quote a 20 yr polar bear biologist about just the straights area alone, " There arent just a few more bears, theres a hell of a lot more bears."



Polar bears are quite old in their current form.. HOW did they ever "survive" periods that had MUCH higher CO2 levels??
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:19pm PT
Try again, what's the answer to my question?
dave729

Trad climber
Western America
May 21, 2013 - 05:20pm PT
Why must we believe the agenda driven global warming people and not our lying eyes?

Alaska
Global Warming skeptics win $318,500 for guessing the Tanana River ice
off date of May 20, 2013 rather than in the usual break up times in the middle of April.

http://www.alaskadispatch.com/article/20130520/97-year-old-nenana-ice-classic-sets-record-latest-breakup-river-1









Skeptimistic

Mountain climber
La Mancha
May 21, 2013 - 05:23pm PT
Hmm... I wonder if the "increase" in the number of bears in a defined area is possibly due to the decrease in habitable areas elsewhere...?
mountainlion

Trad climber
California
May 21, 2013 - 05:24pm PT
yeah Ron...I am a bleeding heart...here is a documented tale of a mother polar bear (with cubs) setting the continuous swimming record (she was tagged) and swam for NINE STRAIGHT DAYS :0 lost 22 percent of her body weight and her cub drowned...


http://news.nationalgeographic.com/news/2011/07/110720-polar-bears-global-warming-sea-ice-science-environment/


Do I believe there is evidence of a polar bear recovery??? Show me the documented evidence and I will take a look at it and it's source---if the source is credible and the research documenting the polar bear population is sound I will stand corrected...but I will still care about the polar bear!!
Norton

Social climber
the Wastelands
May 21, 2013 - 05:24pm PT
Alaska
Global Warming skeptics win $318,500 for guessing the Tanana River ice
off date of May 20, 2013 rather than in the usual break up times in the middle of April.

yeah, tell em Dave!

that proves beyond doubt that 97% of the world's very best scientist are WRONG about the earth geting warmer

and all those record high temps set just in the last couple of years are LIES

what are you, 15?
crunch

Social climber
CO
May 21, 2013 - 05:28pm PT
Ron, what's the clue, in the first two words of your funnyman's graph, that it was not drawn by any scientist?

hey, that's a fine graph...damn straight...oh wait....
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:30pm PT
chiloe,, i havent a clue..


now answer mine: how did polar bears survive higher CO2 levels in the past?

Its all hooohaw. They more than likely evovled from lower brown bear forms and could easily do the reverse of needed. Just like the crocodile and othr ANCIENT life forms that have survived many a catastrophic period of the past. Perfectly acceptable cross breeding those ursus types.


mt lion, do yur own research. PLENTY of factual out there. As per your poor drowning cub story,, wake UP! Damm skippy bears drown every year,, ad do elk, deer, coyotes, PEOPLE, and all other critters fiddling around ice.

You gulped it down hook line a sinker. it is THAT propaganda that has ben soundly prove to be b-u-l-l...
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:31pm PT
Hmm... I wonder if the "increase" in the number of bears in a defined area is possibly due to the decrease in habitable areas elsewhere...?

Skep, that is something biologists have learned may happen when scientific surveys and resident accounts of bear contacts suggest opposite trends. It's possible for a population to be declining even while contacts with humans are increasing, if that's where hungry bears come looking for food.
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:35pm PT
guess ill ask again,, how did the polar bear survive higher CO2 content?


And why is it the USA was the only ban,, not even Canada joined that.
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:35pm PT
chiloe,, i havent a clue..

True dat.


now answer mine: how did polar bears survive higher CO2 levels in the past?

Tell me more about this time, Ron. When was it that polar bears were surviving higher CO2 levels?
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:38pm PT
Polar bears have been chilling on the ice far longer than is generally thought, new research suggests, and they probably interbred with brown bears at one point after the two species separated.

The new German study contradicts data from a study published last July in the journal Current Biology that suggested polar bears separated from brown bears 150,000 years ago. The new study analyzed the bears' mitochondrial DNA, a special "additional genome" that lives in the cell's energy factories and is passed down only from the mother. The new study concludes that the bears became separate species closer to 600,000 years ago.

If the polar bears were only 150,000 years old, as suggested by the previous study, they would have had to evolve many specialized traits in a curiously brief time, the German researchers said.
Chiloe

Trad climber
Lee, NH
May 21, 2013 - 05:38pm PT
hey, that's a fine graph...damn straight...oh wait....

+1 for crunch
Ron Anderson

Trad climber
Soon to be Nipple suckling Liberal
May 21, 2013 - 05:39pm PT
Credit: Ron Anderson
mountainlion

Trad climber
California
May 21, 2013 - 05:41pm PT
Ron your losing credibility with me (probably everybody but I can't speak for anyone else)...You won't provide links to the documented studies that show polar bear populations are increasing...what am I supposed to BELIEVE you had a conversation with somebody (no name given by you) and they SAID the bear population was increasing---sounds a little fishy are you sure you weren't talking to one of your stuffed animals while high on formaldahyde??
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