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Post by brobear on Mar 26, 2017 12:04:55 GMT -5
www.nwf.org/News-and-Magazines/National-Wildlife/Animals/Archives/2006/Grizzly-Bears-on-Ice.aspx Aklak vs. Nanook: A Tale of Two Bears Like most scientists, the Inuit view Aklak, the grizzly bear, and Nanook, the polar bear, as two very different creatures. Their traditional tales of polar bears almost always portray these animals as powerful, keen-witted and worthy of great esteem. The grizzly, on the other hand, is seen as a more sinister beast, one that is likely to charge unexpectedly in an explosive manner. Some biologists might agree with that assessment, citing evidence that barren ground grizzlies appear to be more aggressive than grizzlies living farther south. One explanation, they say, could be that northern grizzlies evolved in a treeless world where there's no place to hide, so threatening one's opponent may make far more sense than fleeing. Whatever the reason, bear biologist Andrew Derocher says he is "a lot more comfortable capturing a big polar bear on the sea ice than a small grizzly on land. Grizzlies tend to react much more aggressively. It can be very unnerving."
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Post by brobear on Mar 26, 2017 13:02:21 GMT -5
sciencenordic.com/grizzly-polar-bear-hybrids-spotted-canadian-arctic Meet the Pizzly, or should that be Grolar Bear? These unusual looking bears, which are a mixture of polar bear and grizzly bear, have been popping up around the Canadian Arctic since the first reported shooting in 2006.Eight further sightings have followed and were confirmed as polar-grizzly hybrids by DNA testing. A ninth sighting is now awaiting the results of a DNA analysis before that too can be confirmed as a hybrid.The bears essentially look a little bit like mum and a little bit like dad, with cream or light tan fur, intermediate claws, a slender polar bear snout, and the broad, muscular shoulders of a grizzly.“We’ve known for a long time that hybrids between polar bears and grizzly bears were possible. We’ve known from zoo studies in Europe that you can take a male and female from either species and hybridise them, and that their offspring are fully fertile,” says polar bear scientist Andrew Derocher, from the University of Alberta, Canada, who studies polar bear populations in the Canadian Arctic and Hudson Bay.“To date, all the confirmed hybrids are in Canada. But that doesn’t mean that they couldn’t exist in Russia for example, where these species come very close to each other, or in Alaska, where they also overlap,” he says. Grolar bears a result of climate changeClimate change is in part responsible for the emergence of these grolar hybrids, as polar bears that live and hunt on the ever-shrinking Arctic sea ice are forced on land during mating season in spring and summer.At the same time, male grizzly bears are expanding their habitats, roaming into polar bear territories, and emerging from hibernation earlier in the year.Inuit hunters have spotted grizzly bears in the Arctic for decades, but numbers are believed to have increased recently, causing males to disperse further in search of a female.The result is that where the two species meet, they mate, says Derocher.Genetic similarities allow cross breedingInterbreeding between two closely related species is nothing new, says evolutionary biologist Eline Lorenzen, from the University of Copenhagen, Denmark. All it takes is for two species or sub-species that were separated for a period of time to be brought back into contact. So long as they still have enough genetic similarities, they can mate and produce fertile offspring. And we only have to look at our own species for evidence of this.“Neanderthals living in Eurasia and Homo sapiens in Africa are a good example. They diverged for a couple of hundred thousand years and then came back into contact. Now all human populations outside of Africa carry a genetic signature from Neanderthals,” says Lorenzen.“So in our own species, hybridisation and borrowing genetic material from another lineage that allows you to adapt to your environment, has occurred before,” she says. Polar bears and grizzlies have interbred before Studies of bear DNA shows that polar bears and brown bears have also interbred before, says Lorenzen, who has previously mapped the genome of 89 polar bears. She discovered that polar bears and brown bears first diverged as a species between 479,000 and 343,000 years ago.Since then, the two species have met and interbred several times, and today, brown bears (also referred to as grizzly bears) still retain some of this ancient polar bear DNA, and vice-versa.“So the fact that species are mixing is not unique in any way. But what is unique now, is that there is a very real chance that a large portion of Arctic sea ice is going to disappear relatively rapidly, and so we will see many more examples of the two species meeting than has been the case before,” says Lorenzen. The polar bear’s unique set of genetic adaptations could be lost. Some of the recent pizzly sightings in Canada are now second generation hybrids, dominated by grizzly DNA.“When I say hybrids I’m referring to half polar bear and half grizzly bear. But I know of four individuals that are three quarters grizzly and one quarter polar bear. So we have a hybrid mating with a grizzly bear and we get a second generation that is three quarters grizzly,” says Derocher.The dominance of grizzly DNA is a concern to both Derocher and Lorenzen, who suggest that polar bears’ unique genetic traits that allow them to live on sea ice and survive on a high fat diet of seals, might ultimately lose out to the dominant population of grizzlies.“Ultimately, one species will be integrated into the other, and it’s likely that it will be polar bears that integrate into brown bears,” say Lorenzen.“As polar bears are forced to go on land and interbreed with brown bears then the selective pressures for being able to metabolise fatty acids--that polar bears need--won’t be important any more. So these will likely be lost. Now if that’s your definition of a polar bear then that will be lost as well,” she says.No new species of bear expected any time soonSo could these hybrids and their offspring become a new species?Until now, they have been considered more of a scientific curiosity, but they are receiving more attention as their numbers continue to rise.“The big question now is how these hybrids live,” says Derocher, and right now this is anyone’s guess.“The first hybrid lived a more terrestrial lifestyle. But I’ve seen from as early as 1986 and most recently in 2013 and 2014, male grizzlies on the sea ice, much further away from where we’d expect to see them and well into polar bear territory. It looked like it was hunting seals, which it wouldn’t normally do,” he says.But asked whether they expect a new species of bear to arise any time soon, both Derocher and Lorenzen say, no.It would take somewhere in the order of hundreds of thousands of years for a new species to arise, and it certainly could not occur within our life times, says Lorenzen.
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Post by brobear on Mar 26, 2017 13:03:34 GMT -5
( Bear Math ).... Polar + Grizzly = Grolar.
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Post by brobear on Apr 19, 2017 18:38:38 GMT -5
www.adn.com/arctic/article/unraveling-mystery-grolars-grizzlies-mate-polar-bears/2013/04/04/ Unraveling the mystery of grolars -- grizzlies that mate with polar bears Published April 4, 2013 When he heard the news of a grizzly-polar bear hybrid shot in Canada's Arctic, Tom Seaton thought back to an unusual polar bear hide he'd once seen at Nelson Walker's home in Kotzebue. "He had two polar bear rugs in his house — one was a huge one, and the other was special. It had lots of brown in it," Seaton said. "It looked like a regular polar bear, but for every square inch of hide, 5 to 20 percent of the hairs were brown instead of white." Walker, who has since passed on, was a polar bear hunting guide in the village. Seaton was then a teenage hunter who loved to listen to Walker's stories. He's now a biologist with the Alaska Department of Fish and Game in Fairbanks. Because he had heard that polar bears and brown bears had bred successfully in a zoo, Seaton was pretty sure Walker's white-and-brown hide was from the mating of a polar bear and a brown bear. Confirmation from DNA tests That combination of large bears is so rare that DNA testing of the hybrid bear shot in 2006 off Banks Island in Canada's high Arctic proved for the first time that a wild bear had a polar bear as its mother and a grizzly as its father. An Associated Press reporter wrote that the bear had brown patches on its white coat, long claws, and the humped back of a grizzly. Biologists say the merger is unlikely because the two species don't interact much -- barren-ground grizzlies of the Arctic hibernate during much of the time polar bears have access to land. Polar bears are often far out on the sea ice when they're ready to breed, but people sometimes see them on land in summer, as was the case in 1990 when oil exploration workers saw a polar bear 50 miles inland from the Beaufort Sea coast. UAF scientists doing genetic testing about a decade ago found that grizzly bears may be the ancestral fathers of polar bears, which over many thousands of years perhaps evolved to life on sea ice by developing all-white coats, furry feet, and teeth designed to rip seal flesh. People sometimes see the two bears together at whale carcasses, such as a bowhead whale boneyard outside the village of Kaktovik on the shore of the Beaufort Sea. Both polar and grizzly bears feast on the remains of whales harvested by villagers there. Those who have seen the bears there say that the grizzlies, often smaller than the polar bears, dominate the encounter. Brown bears chase off polar bears "They are two very different animals as far as behavior goes," said Geoff York, a polar bear researcher at the USGS Science Center in Anchorage. "When a brown bear comes in at the bone pile, it chases off all the polar bears." Dick Shideler, a biologist at the Alaska Department of Fish and Game in Fairbanks who studies the farthest-north grizzly, has documented grizzly bears on the sea ice north off Alaska's coast. "We've radio collared a grizzly bear who hunts seals in the spring," Shideler said. "Our pilot has tracked him on the ice, going from hole to hole. He's figured it out." Shideler also said biologists from the Northwest Territories have in the past shared reports of what could have been hybrid bears. "There was a grizzly up there towards Banks Island that killed a bunch of seals, and (a pilot) tracked it and saw its tracks intersecting with those of a polar bear," he said. The carpet of tracks on the snow looked like the bears could have mated, Shideler said. "The next year a helicopter pilot saw a female with darker cubs," he said. "And (hybrids) have been reported quite a few times by Natives (of Canada's Arctic)." Biologists don't think "grolar bears" could outcompete either species; a hybrid probably wouldn't forage on land as well as a grizzly bear, and a mottled brown coat wouldn't be the best camouflage on sea ice. Ned Rozell is a science writer with the University of Alaska Fairbanks' Geophysical Institute. Reach him at nrozell@gi.alaska.edu. Used with permission. This column first appeared in 2006.
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Post by brobear on Mar 28, 2018 13:43:10 GMT -5
You have things so twisted. Polar bears were not "white grizzlies" who one day decided to move up North for social reasons. -Absurd. A group of grizzlies ventured northward during their hunts and ( very likely by mere chance ) discovered a new food source in the form of seals. Over time, these grizzlies evolved into our modern polar bears. Yes, the polar bear remains closely related to the grizzly. In fact, no brown bear family tree is complete without the polar bear's presence.
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Post by Polar on Mar 28, 2018 19:42:38 GMT -5
Some good information there, most excellent posts thank you. It demonstrates how closely related the brown and white Bear types are, much more so - than Lions/Tigers. It also shows the dominance attributes still possessed by the Grizzly, and why his (excuse the pun please) forebears stayed in more competitive warmer latitudes whereas his pale cousins went North, where social contact is rarer - more circumspect. Much more complicated than that. Which would you prefer, living in a land with more threat but more food (grizzly) or living in a land with less threat but less food (polar)? Your pick.
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Post by brobear on Mar 29, 2018 5:36:10 GMT -5
Thus far witnessed, the breedings have always been male grizzly to female polar bear. Genetically, the polar bear is a grizzly. In fact, full-blooded barren ground grizzlies have been seen on the ice flows hunting seals right along with their giant polar bear cousins. The idea of bears choosing where to live according to food issues and predatory threats is a bit ridiculous. Polar bears are comfortable in the environment they have adapted to. The grizzlies have moved further north in their never ending quest for food while the natural climate has gone through a short-lasting warming period; which ended in 2008. Now, as the cooling period continues, in earth's natural cycle as the next ice age approaches, as the climate cools, the grizzlies will very likely migrate further south. By the way; grizzly bears actually benefit from the presence of other predators. Unlike the tiger, who will either drive off a wolf pack or kill them, a grizzly will exploit their kills. Big cats try to drive off or kill predator competition while a grizzly will benefit from their hunting skills. In the R.F.E., even though tigers hunt and kill juvenile bears, their bear intake is a small percentage of their diet. Looking at the big picture, grizzlies actually benefit from the presence of tigers by scavenging their kills sometimes by displacing the big cat.
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Post by brobear on Mar 29, 2018 5:45:06 GMT -5
Another observation to consider; it was grizzlies that, sometime during the Pleistocene, ventured into the pure arctic, the land of sea and ice, to hunt seals and walrus. Their is a lot of meat in the arctic and no vegetation. Sound like a place that should have been better suited for wolves or big cats. But it was the big omnivore who conquered this harsh environment - the one who was tough enough - the one who could endure the climate - the one intelligent enough to observe and contemplate survival strategies - the original "King of Beasts".
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Post by Deleted on Mar 29, 2018 21:40:19 GMT -5
This may be an easy question to answer, but can a Groalar Bear mate with another Grolar Bear and produce offspring? Or do they face the same issue as Ligers do?
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Post by tom on Mar 30, 2018 9:03:20 GMT -5
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Post by brobear on Oct 13, 2018 7:00:15 GMT -5
www.seeker.com/grizzly-bears-enter-polar-bear-territory-1765029304.html Grizzly Bears Enter Polar Bear Territory Grizzly bears have entered polar bear territory, setting the stage for deadly bear versus bear encounters to come, suggests a study recently published in the journal Canadian Field Naturalist. Should the bears meet, the grizzlies could do some serious damage. "This is worrying for the polar bears because grizzly bears would likely hibernate in polar... BY JEN VIEGAS PUBLISHED ON 02/23/2010 2:05 PM EST Grizzly bears have entered polar bear territory, setting the stage for deadly bear versus bear encounters to come, suggests a study recently published in the journal Canadian Field Naturalist. Should the bears meet, the grizzlies could do some serious damage. "This is worrying for the polar bears because grizzly bears would likely hibernate in polar bear maternity denning habitat," explained Linda Gormezano, a co-author of the paper. "They would come out of hibernation at the same time and can kill polar cubs." (Go to this page to see a video of a polar bear cub nursing.) Gormezano and her colleagues documented sightings of the bears in Canada's Wapusk National Park. The bears are moving into the Canadian province of Manitoba in regions traditionally thought of as polar bear habitat. "Grizzly bears are a new guy on the scene, competition and a potential predator for the polar bears that live in this area," said Robert Rockwell, who also worked on the study. He is a research associate at the American Museum of Natural History and a professor of biology at the City College of the City University of New York. He shared that "the first time we saw a grizzly we were flying over the middle of Wapusk, counting fox dens" when Gormezano "shouted, 'Over there, over there-a grizzly bear.' And it wasn't a dirty polar bear or a moose-we saw the hump." Before 1996, there was no evidence that grizzly bears encroached on polar bear territory. From that year on, however, there have been at least 12 sightings, negating the prior theory that the barren landscape north of the Hudson Bay was impassable, in terms of resources, for migrating grizzly bears. But the flexible bears, which can eat everything from meat to berries, have crossed the gap and likely won't look back much, since the polar bear region is known for its abundant caribou, moose, fish and berries. "Although we don't yet know if they are wandering or staying-the proof will come from an observed den or cubs-these animals will eventually be residents of this national park," said Rockwell. "The Cree elders we talked to feel that now that grizzly bears have found this food source they will be staying." Gormezano continued, "A big question is how to deal with these new residents. In Canada, both the polar and grizzly bear are federally listed as species of special concern. In Manitoba, the polar bear is provincially listed as threatened while the prairie population of the grizzly bear is listed as extirpated."
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Post by brobear on Oct 13, 2018 7:01:58 GMT -5
extirpate verb ex·tir·pate | \ˈek-stər-ˌpāt \ extirpated; extirpating Definition of extirpate transitive verb 1a : to destroy completely : WIPE OUT b : to pull up by the root 2 : to cut out by surgery www.merriam-webster.com/dictionary/extirpate
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Post by King Kodiak on Oct 13, 2018 7:14:06 GMT -5
If this is happening more and more, the polars will have to learn to cope with the grizzly bears, they will have to learn to defend their cubs. Habitat lose is driving the grizzlies to the polars habitat.
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Post by brobear on Oct 13, 2018 7:34:13 GMT -5
If this is happening more and more, the polars will have to learn to cope with the grizzly bears, they will have to learn to defend their cubs. Habitat lose is driving the grizzlies to the polars habitat. Nature will take its course. Mother polar bears will most definitely defend their cubs. Most disputes will be over a carcass, be it seal, walrus, or whale. Through the eyes of a grizzly, I believe they see polar bears as simply bigger grizzlies. Once the polar bears become more accustomed to their shaggy little new neighbors, they will likely view the grizzlies as smaller versions of their own kind as well. I honestly believe that the scientific name for polar bear, instead of Ursus maritimus should instead be: Ursus arctos maritimus.
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Post by King Kodiak on Nov 18, 2018 8:25:42 GMT -5
www.thesun.co.uk/news/5709762/pizzly-bear-polar-bear-grizzly-bear-hybrids-spotted/amp/RARE BEAR BUNCH What is a pizzly bear and where have the polar bear and grizzly bear hybrids been spotted? Hybrid bears are thought to have sprung up when polar bears were forced south as their arctic habitat shrank through global warming By Neal Baker 2nd March 2018, 12:11 pm Updated: 2nd March 2018, 12:12 pm ADD COMMENT YOU’VE heard of polar bears, you’ve heard of grizzly bears — but what about PIZZLY bears? These rare hybrid creatures were first seen in the wild in 2006, but what are they? Here’s all you need to know. Pizzly bears are a cross between polar bears and grizzlies WIKIPEDIA Pizzly bears are a cross between polar bears and grizzlies What is a pizzly bear? Pizzly bears, also known as grolar bears and nanulaks, are a cross between a polar bear and a grizzly bear. Although polars and grizzlies are genetically similar, they tend to avoid each other in the wild. Grizzlies tend to live and breed on land and polar bears tend to live on the ice and hunt in water. But theories suggest some polar bears may have increasingly moved south from the arctic due to global warming reducing its icy habitat. But DNA testing on a suspected pizzly in 2006 confirmed that it was the result of cross breeding. It had been spotted and shot by Idaho hunder Jim Martell in the Northwest Territories of Canada. He had believed it to be a polar bear, but officials took interest when it was noticed it had grizzly traits. The bear had long claws, a humped back, a shallow face, and brown patches around its eyes, nose, back, and foot. A DNA test conducted by Wildlife Genetics International in British Columbia confirmed it was a hybrid, with a polar bear mother and a grizzly bear father. Pizzlies have cream-coloured fur like polars, but grizzly traits like long claws and brown patches WIKIPEDIA Pizzlies have cream-coloured fur like polars, but grizzly traits like long claws and brown patches Where have the polar bear and grizzly bear hybrids been spotted? They have only been seen in the wild in northern Canada. Another pizzly bear was spotted in 2010 by David Kuptana, an Inuvialuit hunter. He killed the animal on the remote Victoria Island in Canada believing it to be a polar bear. DNA tests confirmed the bear’s mother was a grizzly-polar hybrid and the father was a grizzly bear. The Department of Environment and Natural Resources for the Northwest Territories said that it “…may be the first recorded second-generation polar-grizzly bear hybrid found in the wild” Two grizzly–polar hybrid cubs (one female and one male) were born at Osnabrück Zoo in Osnabrück, Germany, in 2004.
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Post by tom on Nov 20, 2018 13:39:02 GMT -5
I wonder if there are differences in Pizzlies depending on which parent was the sow and which is the boar.
For instance with Ligers you cross a male Lion with a female Tiger. A cross between a male Tiger and a female Lion is called a Tigon. Each pairing produces a different looking offspring with Ligers generally being much larger.
So... what if any differences would occur with mating a male Polar bear to a female Grizzly vs Male Grizzly with female Polar? Would they look different and which pairing would produce larger offspring?
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Post by brobear on Nov 20, 2018 14:39:03 GMT -5
I wonder if there are differences in Pizzlies depending on which parent was the sow and which is the boar. For instance with Ligers you cross a male Lion with a female Tiger. A cross between a male Tiger and a female Lion is called a Tigon. Each pairing produces a different looking offspring with Ligers generally being much larger. So... what if any differences would occur with mating a male Polar bear to a female Grizzly vs Male Grizzly with female Polar? Would they look different and which pairing would produce larger offspring? Interesting thought. Thus far, every known case has been from male grizzly and female polar bear.
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Post by Deleted on Dec 16, 2018 2:30:01 GMT -5
During mating season, male polar bears and male grizzlies do fight to death. The reason the grizzly gets to mate with a female polar bear is because younger bears prefer to mate with younger bears (read info from a poster name Ursus Artos). Therefore, younger polar bears get picked out by adult barren grizzlies (there is an account where a grizzly killed a 2 year old polar bear) during competition at a seal breathing hole.
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Post by BruteStrength on Dec 17, 2018 22:04:44 GMT -5
During mating season, male polar bears and male grizzlies do fight to death. The reason the grizzly gets to mate with a female polar bear is because younger bears prefer to mate with younger bears (read info from a poster name Ursus Artos). Therefore, younger polar bears get picked out by adult barren grizzlies (there is an account where a grizzly killed a 2 year old polar bear) during competition at a seal breathing hole. I put polar bears and brown bear at similar strength with the brown bear being stronger because of the shoulder hump.
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Post by Deleted on Dec 18, 2018 0:09:28 GMT -5
Brutestrength, I totally agree with you, however, a 1000 pound polar bear will be stronger than a barren ground grizzly which seldoms exceeds 400 pounds. Pound to pound, the brown bear will be the stronger one.
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