Sub-Species

[brobear]

As with other bear species, the polar bear must also have some list of sub-species. Anyone... ? 

[King Kodiak]

The polar bear is not known to have different subspecies, its just the species Ursus Maritimus, thats it. We had Ursus maritimus tyrannus in the late Pleistocene, but we know that it was most likely a brown bear according to most scientists.

[OldGreenGrolar]

I agree with King Kodiak. The polar bear does not have any subspecies. Ursus Maritimus tyrannus is either a 400 pound brown bear or a Steppe brown bear. The Alaskan giant polar bear is a cryptic.

[brobear]

en.wikipedia.org/wiki/Polar_bear#Population_and_distribution

Population and distribution: The polar bear is found in the Arctic Circle and adjacent land masses as far south as Newfoundland. Due to the absence of human development in its remote habitat, it retains more of its original range than any other extant carnivore. While they are rare north of 88°, there is evidence that they range all the way across the Arctic, and as far south as James Bay in Canada. Their southernmost range is near the boundary between the subarctic and humid continental climate zones. They can occasionally drift widely with the sea ice, and there have been anecdotal sightings as far south as Berlevåg on the Norwegian mainland and the Kuril Islands in the Sea of Okhotsk. It is difficult to estimate a global population of polar bears as much of the range has been poorly studied; however, biologists use a working estimate of about 20–25,000 or 22–31,000 polar bears worldwide.

There are 19 generally recognized, discrete subpopulations, though polar bears are thought to exist only in low densities in the area of the Arctic Basin. The subpopulations display seasonal fidelity to particular areas, but DNA studies show that they are not reproductively isolated. The 13 North American subpopulations range from the Beaufort Sea south to Hudson Bay and east to Baffin Bay in western Greenland and account for about 54% of the global population.

The range includes the territory of five nations: Denmark (Greenland), Norway (Svalbard), Russia, the United States (Alaska) and Canada. These five nations are the signatories of the International Agreement on the Conservation of Polar Bears, which mandates cooperation on research and conservation efforts throughout the polar bear's range. Bears sometimes swim to Iceland from Greenland—about 600 sightings since the country's settlement in the 9th century AD, and five in the 21st century as of 2016—and are always killed because of their danger, and the cost and difficulty of repatriation.

Modern methods of tracking polar bear populations have been implemented only since the mid-1980s, and are expensive to perform consistently over a large area. The most accurate counts require flying a helicopter in the Arctic climate to find polar bears, shooting a tranquilizer dart at the bear to sedate it, and then tagging the bear. In Nunavut, some Inuit have reported increases in bear sightings around human settlements in recent years, leading to a belief that populations are increasing. Scientists have responded by noting that hungry bears may be congregating around human settlements, leading to the illusion that populations are higher than they actually are.[43] The Polar Bear Specialist Group of the IUCN Species Survival Commission takes the position that "estimates of subpopulation size or sustainable harvest levels should not be made solely on the basis of traditional ecological knowledge without supporting scientific studies."

Of the 19 recognized polar bear subpopulations, one is in decline, two are increasing, seven are stable, and nine have insufficient data, as of 2017. 
 
*OK; 19 recognized polar bear subpopulations - evidently not considered as sub-species.

[King Kodiak]

OK; 19 recognized polar bear subpopulations - evidently not considered as sub-species. 

Right, just populations.

[King Kodiak]

Apr 29, 2020 4:12:57 GMT -5 OldGreenGrolar said:

I agree with King Kodiak. The polar bear does not have any subspecies. Ursus Maritimus tyrannus is either a 400 pound brown bear or a Steppe brown bear. The Alaskan giant polar bear is a cryptic.

Well, Ursus Maritimus Tyrannus was huge though, it weighted 400 kg (881 lbs) and went up to around 2200 lbs, (all estimates). I think you meant to say 400 kg, not pounds.

domainofthebears.proboards.com/thread/904/ursus-maritimus-tyrannus