|
Post by tom on Jan 25, 2018 12:25:45 GMT -5
Lots of talk about how the polar ice caps are shrinking and the Polar Bears days may be numbered, but are they? Nasa Study: www.forbes.com/sites/jamestaylor/2015/05/19/updated-nasa-data-polar-ice-not-receding-after-all/#257b29892892If in fact they are shrinking then the obvious answer whether the Polar bears days are numbered is likely yes. I've seen many documentaries that point to the yes as the Polar bears are having to travel much further distances due to less ice, many times swimming many miles in open arctic waters to find food. www.polarbear-world.com/future-of-polar-bears/There seems to be some inconsistencies in the science as to whether the so-called global warming theory if one chooses to believe it is actually true and having an affect on the polar ice caps. Al Gore would like us all to believe this.... There seems to be some evidence to refute this as well as support it. The earth has endured many cyclical climate changes over millions of years and some scientists (Climatologists) seem to think this is another cycle and not permanent global warming. We will likely never know the truth in our lifetime, but it does make you stop and ponder.
|
|
|
Post by brobear on Jan 25, 2018 18:33:29 GMT -5
There is no global warming - there was for a short period of time. It ended in 2008. But the Liberals keep spouting that it is still real. The weather changes is part of a natural cycle and ( get this ) we are actually heading fast into an Ice Age. I watched the documentary ( non-political ). ..... www.barnesandnoble.com/w/dark-winter-john-casey/1120035050#/
|
|
|
Post by brobear on Jan 27, 2018 21:03:56 GMT -5
twilightbeasts.wordpress.com/2017/10/02/walking-on-thin-ice/ No other animal symbolises climate change like the polar bear does. Just like the dodo has become the standard animal representing extinction, the polar bear has become recognised as the animal signifying our impact on the planet’s rapidly warming climate. TV programmes, newspapers and magazines all use an image of a polar bear when talking about climate change. There is the classic image of a lone polar bear standing on all fours on a small piece of ice, in the vastness of empty water. The fur is wet, and clearly this large creature is being portrayed as being very cold. Its thick padded, webbed feet, grip onto the freezing ice. The great white bear is looking out longingly to sea, searching for that next piece of ice it can swim to, hoping that there is a tasty seal just lying there waiting. It is an extremely powerful image. A great creature, losing its home because of our selfishness. It is a stark reminder of the enormous effect we can have on our home; the home of millions of different species, each unique, and each just as beautiful as the next. Polar bears belong to a rather remarkable genus in the bear family, Ursus. Species from this group have conquered the northern hemisphere: the brown bear (Ursus arctos) living in North America and Eurasia; the widely distributed American black bear (Ursus americanus); the tree loving Asian black bear (Ursus thibetanus); and the one that made its home with the sea and ice, the polar bear (Ursus maritimus). For just one genus, this is hugely successful: species are found all over North America, and Asia, and even the northern cold ice sheets. In the past there have been over a dozen different types of bear placed in this genus, including the giant Cave Bear. Out of the four living species, the polar bear is the largest. And perhaps the most bizarre. Polar bears are bears. Bears that hibernate, like other bears. But polar bears dig a den deep underneath the snow, and hibernate inside a snow-den! Their thick hair and layers of fat allow this giant to survive the freezing temperatures. Unlike other bears, the polar bear can swim for a very long time: up to a week non-stop. Their huge padded feet help spread the weight when walking on the ice, and it also helps in swimming. This bear also hunts seals: yes, the polar bear decides to spent a lot of time hunting an animal that is superbly adapted to life in the water. (Polar bears do not solely rely on seals for food. They will eat other animals, including washed up whale carcasses, as recently seen on Wrangel Island.) Surprisingly, these are a very recent species to appear. Evolving from a population of brown bears, the oldest polar bear fossil so far found is only around 110,000 years old on the Norwegian archipelago, Svalbard. With much of the Arctic Ocean frozen over during the Late Pleistocene, some brown bears slowly took advantage of this dramatic change in environment. The heritage with brown bears is important, because the two species still can produce hybrids. Locked within the genomes of polar bears is a genetic marker that shows all living polar bears alive today are descended from a brown bear – likely due to polar bear and brown bear mating in the recent past. Researchers had assumed this had been fairly recently, somewhere in Alaska where the two species can overlap. Recent work by geneticist Beth Shapiro and colleagues looked at DNA from brown bears in Ireland. They showed that all polar bears alive today are descended from one Irish female brown bear (and a male polar bear). Polar bears in Britain and Ireland? It sounds crazy today, but during the Late Pleistocene the world was a drastically different place. The last major glaciation was between 110,000 to 11,700 years ago. (Remember, the ‘ice age’ was not just one long cold stage, but a plethora of cold times, known as glacials, and warm times known as intergalcials.) During this cold time, ice covered much of the Northern Hemisphere, which provided the conditions for brown bears to take advantage of, and we see the first polar bears around this time. With so much ice around, the sea levels were much lower, so animals could move much more freely. Britain itself was at some points covered by glaciers up to two miles thick, as far south as the Thames. This would have been the perfect environment for polar bears. And it seems that around 50,000 years ago one male polar bear met a female polar bear, and their descendants are what we see today. Monster mysteries are popular all around the world. The legends of Bigfoot, sasquatch, and the Yeti, may all be answered by bear DNA. Samples of hair which have been claimed to belong to these cryptozoological beasts, were taken from across Northern America and the Himalayas and their DNA was analysed. The results showed the hair was actually from a huge variety of real animals, including horses, dogs, cows, and an odd result which we shouldn’t try to think about too much, a human. Some of the results showed that the ‘Bigfoot’ or ‘Yeti’ actually came from Himalayan brown bears. Sadly, the myths of a giant, hairy, bipedal creature is just that: a myth. This symbolic species owes it’s existence to the incredibly dramatic climate of the last major glaciations. The last 100,000 years or so has not been easy sailing for these animals. The temperature has fluctuated, with the ice sheets waxing and waning which has had an effect on polar bear populations. Today is a different story. Different because of a factor no animals can prepare for: humans. We are having an effect on the whole planet in a way no other species has since maybe stromatolites changed the atmosphere to be more oxygen rich some 2 billion years ago. There is a reason why polar bears are the symbol for climate change. They have had to cope with temperature changes in the past as their environment shrunk. The difference today is that it is happening fast, faster than natural. Because of our actions, species are unable to respond fast enough to the changes at not just a local level, but at a global level. The polar bear is the poster species for climate change, but there are millions others that are in danger of being lost forever. Climate change is real. It is happening. We al have a responsibility to do what we can. Written by Jan Freedman (@janfreedman)
|
|
|
Post by King Kodiak on Sept 10, 2019 14:33:11 GMT -5
The Myth That the Polar Bear Population Is Declining The story of a resurgent polar bear population deserves to be told and applauded. Many of us watched the viral video in horror. A starving polar bear scavenging for food on barren land, his ribs visible beneath a jaundiced white coat. “This is what climate change looks like,” said National Geographic. The magazine explained that because of melting sea ice, precipitated by climate change, more of these mammals are starving. They pointed to a new study in Science suggesting that polar bears require much greater caloric intake in their diet than previously believed. The video, shot by photographers Paul Nicklen and Cristina Mittermeier on Somerset Island, sparked outcry over the decimation of polar bears due to global warming. The footage was viewed by 2.5 billion people, National Geographic estimated. The video remains the most viewed on National Geographic’s website—ever. What Followed While many remember the footage of the polar bear, fewer are aware of what followed. As Michele Moses recently explained in The New Yorker, scientists accused National Geographic of “being loose with the facts.” There was no evidence, many pointed out, that the bear’s condition was the result of climate change. The bear simply could have been old, ill, or suffering from a degenerative disease. Mittermeier admitted as much a year later. “I can’t say that this bear was starving because of climate change,” she wrote in National Geographic. Perhaps we made a mistake in not telling the full story—that we were looking for a picture that foretold the future and that we didn’t know what had happened to this particular polar bear. The Polar Bear as a Symbol Mittermeier was looking for visual evidence of the future she imagined, one ravaged by climate change. And she found one that day in a starving bear. As Moses of The New Yorker points out, polar bears have become an “indisputable image of climate change.” “The story of climate change has been told, in part, through pictures of polar bears,” Moses writes. “And no wonder: in their glittering icy habitat, they reflect the otherworldly beauty that rising temperatures threaten to destroy.” That picture of a single starving bear arguably did more to advance the issue of climate change than any white paper or IPCC report could have. Unfortunately, the footage tells us relatively little about the actual state of the polar bear population. What the Numbers Say While you’ll find no shortage of headlines declaring that polar bears face extinction, the numbers tell a different story. The State of the Polar Report 2018 put the new global mid-point estimate [of the polar bear population] at more than 30,000. Data from conservation groups and the government show that the polar bear population is roughly five times what it was in the 1950s and three or four times what it was in the 1970s when polar bears became protected under international treaty. In fact, though polar bears were placed under the protection of the Endangered Species Act in 2008 over concerns that its Arctic hunting grounds were being reduced by a warming climate, the polar bear population has been stable for the last three decades. In 1984, the polar bear population was estimated at 25,000. In 2008, when polar bears were designated as a protected species, The New York Times noted that number remained unchanged: “There are more than 25,000 bears in the Arctic, 15,500 of which roam within Canada’s territory.” New estimates from the International Union for Conservation of Nature show a mid-point estimate of 26,500 (range: 22,000 to 31,000) in 2015. In The State of the Polar Report 2018, zoologist Susan J. Crockford says updates to IUCN data put the new global mid-point estimate at more than 30,000. Even accepting the lower figure, the estimate is the highest since the polar bear became internationally protected in 1973. The health of the polar bear population runs counter to predictions from scholars who have said two-thirds of polar bears will disappear in coming decades because of warming temperatures and melting sea ice in the Arctic. The good news that polar bears are thriving is unlikely to draw as much attention as images of a starving polar bear scrounging for food on Somerset Island. Nevertheless, the story of a resurgent polar bear population deserves to be told and applauded. fee.org/articles/the-myth-that-the-polar-bear-population-is-declining/
|
|
|
Post by tom on Sept 11, 2019 7:51:00 GMT -5
I'm still skeptical. I would like to see this study and who and just how they came up with those numbers.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Sept 11, 2019 9:46:53 GMT -5
^ I have heard that their number is increasing due to the restriction in hunting (compared to earlier days). However, i don't think they're doing super well either. Polar bears depend heavily on sea ice in order to help them catch seals. Without sea ice, Polar bears have virtually zero chances of catching them (as the seals could just outswim them easily). The loss of sea ice will undoubtedly detrimentally affects them in one way or another. The question here is whether they will be able to adapt and rapidly evolve (like they once did) or they will die out. Though i must say the Polar bears' conditions do appear to be more on a bright side compared to many other megafaunas. Some of the Polar bears' sub-populations such as Foxe Basin and Churchill Sea do appear to be fairly stable ( link). So yeah, certainly more positive than other megafaunas such as Siberian tigers, Philippine eagles, or African wild dogs, whose conditions are rather depressing.
|
|
|
Post by King Kodiak on Sept 11, 2019 9:54:58 GMT -5
From Verdugo’s link:
The most recent population data comes from an aerial survey of Foxe Basin in 2009/2010, which generated an estimate of ~2,580 bears, slightly above the early 1990s estimate of ~2,300 (Stapleton et al. 2012). While the two methods (aerial survey and mark-recapture) are not directly comparable, the aerial survey does suggest the population has not declined. It is now considered stable.
This is awesome as the polar bears of Foxe Basin have the largest average weights of any population.
|
|
|
Post by King Kodiak on Sept 11, 2019 11:02:40 GMT -5
I'm still skeptical. I would like to see this study and who and just how they came up with those numbers. The source looks pretty good to me. This here is the author of the study, an evolutionary biologist.
About the author Dr Susan Crockford is an evolutionary biologist and has been working for 35 years in archaeo- zoology, paleozoology and forensic zoology.2 She is an adjunct professor at the University of Victoria, British Columbia, but works full time for a private consulting company she co- owns (Pacific Identifications Inc). She is the author of Rhythms of Life: Thyroid Hormone and the Origin of Species, Eaten: A Novel (a polar bear attack thriller), Polar Bear Facts and Myths (for ages seven and up, also available in French and German), Polar Bears Have Big Feet (for preschoolers), and the fully referenced Polar Bears: Outstanding Survivors of Climate Change,3 aswellasascientificpaperonpolarbearconservationstatus.4 Shehasauthoredseveralear- lier briefing papers and videos for GWPF on the subjects of polar bears and walrus.5 Susan Crockford blogs at www.polarbearscience.com.
this here is the actual link to the study:
www.thegwpf.org/content/uploads/2019/02/State-of-the-polar-bear2018.pdf
|
|
|
Post by King Kodiak on Jul 20, 2020 12:47:35 GMT -5
|
|
|
Post by tom on Jul 20, 2020 15:27:53 GMT -5
A very good possibility. My other thought on this is whether Polar bears will adapt to the shrinking ice cap and venture south to land masses and learn to hunt and forage like Grizzlies.
|
|
|
Post by OldGreenGrolar on Jul 20, 2020 18:51:28 GMT -5
Polar bears breed earlier than grizzly bears. This gives the male grizzlies the opportunity to mate with the yellowish white females or kill the polar cubs. There might be more grolar bears than realise. Furthermore, the ABC bears were once polar bears which eventually became brown bears.
|
|
|
Post by OldGreenGrolar on Oct 16, 2020 6:59:42 GMT -5
|
|
|
Post by brobear on Oct 16, 2020 7:16:42 GMT -5
Quote: My other thought on this is whether Polar bears will adapt to the shrinking ice cap and venture south to land masses and learn to hunt and forage like Grizzlies. Quote: Polar bears breed earlier than grizzly bears. *Some polar bears will venture south. I believe this is a sure bet. Those that do will have to completely change their lifestyles. This will likely include breeding habits. Those that venture, and manage to survive, will ( IMO ) blend into the grizzly population through breeding. The biggest hurdle for those southward trekkers will be ( IMO ) humans. Most people will view the big white invaders as an "Invasive Species" just like the pythons in Florida.
|
|
smedz
Ursus abstrusus
Recent Graduate
Posts: 410
|
Post by smedz on Oct 16, 2020 8:14:24 GMT -5
My basic thoughts on a changing climate. www.farmanddairy.com/news/black-vulture-attacks-on-the-rise/431501.html “Black vultures are southern birds,” said Tommy Butler, a certified wildlife biologist with USDA Wildlife Services who spoke July 15 during the Ohio Sheep Day in Wooster. However, in the last 10 to 15 years, the birds have been moving north, he explained. Producers from Summit, Wayne, Ashland and Lorain counties noted they have spotted the vultures near their flocks. vt.co/news/world/scientists-proven-certain-parts-world-actually-getting-colder In truth, some places are colder, some places are warmer, so the term "global warming" is not accurate.
|
|
|
Post by OldGreenGrolar on Nov 9, 2020 9:10:30 GMT -5
Since polar bears come from Steppe brown bears, if the latter is brought back to life by scientist, would they eventually interbreed and merge with the yellowish white bears?
|
|
|
Post by King Kodiak on Nov 9, 2020 10:27:51 GMT -5
Since polar bears come from Steppe brown bears, if the latter is brought back to life by scientist, would they eventually interbreed and merge with the yellowish white bears? Not really. Because the Steppe brown bears will not be placed on the Artic. A group would have to migrate North for that to happen, but there would have to be a very good reason for that migration.
|
|
|
Post by brobear on Nov 20, 2020 12:59:51 GMT -5
Since polar bears come from Steppe brown bears, if the latter is brought back to life by scientist, would they eventually interbreed and merge with the yellowish white bears? Where did you read that the polar bears derived from Steppe brown bears?
|
|
|
Post by OldGreenGrolar on Nov 20, 2020 13:35:43 GMT -5
Since polar bears come from Steppe brown bears, if the latter is brought back to life by scientist, would they eventually interbreed and merge with the yellowish white bears? Where did you read that the polar bears derived from Steppe brown bears? I think you mention it sometime ago during my early days on the forum if not mistaken.
|
|
|
Post by OldGreenGrolar on Nov 29, 2020 6:51:30 GMT -5
Thick camouflaged fur (anatomical) - The coat of the polar bear is especially thick and luxurious being the thickest of any bear (unsurprisingly!). There are two kinds of hairs, short soft dense inner hairs and longer stiffer outer guard hairs. The coat is the same colour all year round unlike some arctic animals which have a darker coat in the summer months. The coat usually appears to be perfectly white, though has a pale yellow tinge to it which becomes more pronounced in older animals. The colour of course provides camouflage against an icy and snowy background. www.coolantarctica.com/Antarctica%20fact%20file/wildlife/Arctic_animals/polar-bear.php
|
|
|
Post by brobear on Apr 5, 2021 4:54:51 GMT -5
|
|