* Perhaps the most noticeable and striking characteristics of a polar bear is its color. The fur shafts themselves are not white. The shafts actually lack pigmentation and are transparent which allows them to scatter and reflect light resulting in ideal camouflage in a world of ice and snow.
* Polar bears paws are also well adapted for the environment in which they live. They can measure up to 304 mm. (12 inches) in width. These large paws allow polar bears to better distribute their weight more evenly across ice surfaces.
* Polar bears do not hibernate. Females will, however, dig dens in the snow and give birth to their cubs in the winter. The den provides insulation and protection until the sow and her cubs emerge.
* The scientific name for polar bear is Ursus maritimus which means sea bear in Latin. They were first identified by Constantine J. Phipps in 1774. Different sources express different theories on the origins of polar bears. Fossil evidence lead researchers to believe that polar bears may have split off from a population of brown bears that became isolated during the Pleistocene epoch. More recent DNA evidence suggests that polar bears became distinct species from brown bears 4-5 million years ago. It has been documented that polar and grizzly bears have produced fertile hybrid offspring. Other names for the polar bear include the Inuit word "nanook", and the Norwegian name of Isbjorn which means "ice bear."
* Polar bears are members of the bear family Ursidae. They are a carnivorous bear which can be found throughout the Arctic region where they rely on sea ice to sustain their hunting activities. Canada hosts approximately 60% of the polar bear population. Other areas inhabited by polar bears include Alas...
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...t of Biological Sciences with the University of Alberta. He has studied polar bears in the Canadian Arctic for over 40 years. His studies have linked the loss of sea ice due to climate change to the decline of the polar bear population.
* Other readings of interest about polar bears:
- Susan McGrath, July - 2011, National Geographic, "On Thin Ice" http://ngm.nationalgeographic.com/2011/07/polar-bears/mcgrath-text?rptregcta=reg_free_np&rptregcampa...
- Ian Stirling, 2011, "Polar Bears, The Natural History of a Threatened Species"
- Pagano, A. M., G. M. Durner, S. C. Amstrup, K. S. Simac, and G. S. York. 2012. Long-distance swimming by polar bears (Ursus maritimus) of the southern Beaufort Sea during years of extensive open water: Canadian Journal of Zoology 90:663-676. doi: 10.1139/z2012-033http://www.nrcresearchpress.com/doi/abs/10.1139/z2012-033#.UxOE1ZWPLoo
These categories are broken down into different genetics of bear species. The most common bear found in Alaska is the black bear. The black bears are smaller than most bears. They are found in almost all states in the US except Hawaii. Most are found in forest, but some may be found in swamps and mountains. An estimated 100,000 black bears live in Alaska.
Lamarck’s ideas on polar bear evolution Lamarckism can be used to explain the evolution of polar bears from brown bears, specifically skin and fur color. Lamarck’s theory stipulated that a characteristic (brown or white fur color) which is used more by an organism will become stronger. One that is not used disappears eventually. Change occurs when polar bears want to change. If a polar bear’s phenotype changes during life in order to adapt its environment, those changes are passed onto its offspring.
Bears can live anywhere but Grizzly bears live in subalpine meadows and dense forests. When grizzly bears hibernate they usually live in caves. A sloth of bears is usually a mom and the cubs. The mom bear is called a sow, the dad bear doesn't have a name because they are never with the family and the babies are called cubs. There is usually a dearth amount of cubs in a family. The families are always together and not with a different family. All bear look different but I'm not talking about the other bears I am talking about grizzly bears. Grizzly bears are usually just the color brown and not really anything different. Grizzlys need big paws to get around and travel. Bears have small black eyes. Their eyes are small because they don't need very good eyesight because they have such good sniffers. Usually the weight of a cub is about 4- 10 pounds when they are born but when they are adults they weigh 175- 500 pounds.
The Arctic region is home to a variety of valuable animals and plants, including polar bear, seal, and so on. The ecosystem of the Arctic region is fragile because these animals are evolved to live in extreme conditions. With the climate change, many animals are endangered. Ice is the habitat of polar animals because they have to rely on sea ices for resting, food, and reproduction. With the climate change and the decrease of sea ice, the number of polar animals is decreasing and their health is threatened. For example, the average weight of female polar bears in 1980 was about 650 pounds, but the number reduced to about 500 pounds in 2004 (Djoghlaf 15). The earlier breakup and later condensation of sea ice shortens the hunting season of polar bears. Polar bears mainly feed on seals that indwell icy land. The melting ice reduces the number of seals and food intake of polar bears. In addition, polar bears are used to living in ice caves. The rising temperature causes the collapse of ice caves, which can kill baby bears. The climate change is negatively affecting the biodiversity in the region and will definitely harm the ecosystem
The grizzly bear trophy hunt is an issue regarding the citizens of Canada who immorally hunt and kill grizzly bears for pride, thrill, and trophy. Many people question whether this is morally acceptable as hunters kill without a conscience. Grizzly bears are vital to Canada’s environment as they are essential to maintaining a healthy ecosystem. As keystone species, they regulate prey, disperse seeds of plants,and aerate soil to maintaining forest health. Due to the vulnerability and over-hunting of grizzly bears, Pacific Wild and many other non-profit organizations, are working to protect wildlife in British Columbia, especially the grizzly bear habitat.
Grizzly bears are enormous bears; that, tend to be misunderstood by others. Many times, they are portrayed wrongly in movies and tv shows. People may go off by things they see; in the movies and immediately suggest that’s the way the grizzly bear is. If others took the time to find information on the grizzly they would see how wrong the movies are about them. For many people grizzly bears can be a mystery such as where they live, what they eat, and whether they hibernate or not. However, with a bit of research answers can be found.
grizzly bears prefered habitat is deserted rivers, wild mountains, and thick and dense forest. Grizzly bears are majestic symbols of the wild. Bears live in and use a variety of habitat types, playing important roles in each one. This makes them an “umbrella species,” meaning that when we protect them and their habitat we also protect many species. Grizzly bears can also help ecosystems by distributing seeds and nutrients through their scat, and occasionally regulating ungulate populations.
Out of an Ice Age emerged one of our most majestic creatures in the world the polar bear. From its brown bear ancestry, the predator evolved to be a master of a harsh and unwelcoming ice kingdom. Intelligent, adaptable and fierce, the polar bear learned how to survive in a place that offers few comforts to any creature. But now that very environment is in flux. And so is the polar bear’s fate (Nature). Polar Bears are very different from other bears. Polar bears are very large bears compared to Black bears. Polar bears weigh anywhere between 330-1700lbs and Black bears weigh anywhere between 150-600lbs. They have strong legs with large, flattened feet with some webbing between their toes that help with walking on ice and swimming. The wide paws prevent sea ice from breaking by distributing weight while walking. Their paws allow them to pull a 600 pound seal out of its breathing hole (Rosing, 20). The webbed feet results in making polar bears, unlike other bear species to be considered as marine mammals along with seals, sea lions, walruses, whales and dolphins (Polar Bear). According to Rosing Polar bears are excellent swimmers and have been known to swim up to six miles an hour and as far as 60 miles at a stretch. The bears paddle with their front feet and steer with their back feet. They often overheat. Sometimes they venture into the waters just to cool off. When a bear climbs on an ice floe, it shakes itself off because it is trying to prevent ice from forming on its fur (22-23). Because of climate change and hunting of polar bears are now becoming an endangered species which is affecting the food chain. We can fix this by going green, banning polar bear hunting and keep creating these new hybrid bears that are mixed with griz...
In recent decades, the global warming threat has captured the attention of the nation and the world. While the main focus began with concentrating on the effects this long-term natural crisis would have on the human population, select groups have worked to approach the topic in a manner that entails prevention in order to help other animal and plant species around the globe. One such organization is the National Oceanic and Atmospheric Administration, which has played a major role in the conservation of the polar bear species, one of the mammals most adversely affected by the recent climate changes. As more research has been conducted regarding the polar bears, scientific name Ursus Maritimus, the conclusions have been shocking. In 2008, the Department to the Interior listed the polar bear species as “threatened” under the Endangered Species Act of 1973 awarding it some protections mandated by the federal government (Wolfe). However, on January 5, 2011, Representative Donald Young proposed a bill in Congress in order to delist the polar bears as threatened, thus decreasing and even removing the conservation efforts that have been set in place over the past three years. The polar bear Species should remain listed under the Endangered Species Act because ice thickness has decreased 40 percent during the past 30 years thus reducing the polar bears’ critical environment, if current conditions continue the polar bear populations around the world may decrease by two thirds by mid century, and since the species has been protected under the Endangered Species Act the worldwide populations have experienced stabilization or growth in most circumstances.
According to the Alaska Department of Fish and Game, the brown bear is located all throughout Alaska, mostly in areas that allow them to seasonally hunt salmon (Alaska Fish & Game, 2010). This allows them to become larger and live in higher concentrations than the grizzly bear. The traditional brown bear and the grizzly bear are actually both classified as brown bears, despite having several differences in appearance. Brown bears are one of the most fascinating and powerful species in the Alaskan wilderness. Cubs are usually born during January or February, usually in groups of one to four (Alaska Fish & Game). A fully grown, male brown bear can weigh up for 1,500 pounds and be over 10 feet in stature (Alaska Fish & Game, 2010). Brown bears also have the ability to run at speeds up to 40 mph for short bursts of time (Alaska Fish & Game). All of these unique characteristics make many people upset that it is legal to hunt them. There are several groups that are working to conserve the brown bear population, particularly in Alaska, such as The Northern Forum’s Brown Bear Working Group (Fish & Wildlife Journal, 2010). The bear population in Alaska is thriving and is classified as a status of least concern, by the IUCN Red List (IUCN, 2010). Overall, the brown bear population faces no danger whatsoever.
To begin with, the melting of polar ice caps has caused polar bears to swim long distances. According to Bryan Walsh of TIME Magazine the melting of the ice caps have caused polar bears especially the young cubs to swim longer distances which has caused a “ forty-five percent mortality rate” (Walsh). In the article Walsh, writes about a study that showed that younger cubs because of low fat and strength were more likely to die due to the long di...
Polar bears don't just live on ice, they use the ice as an advantage to catch prey such as seals. Polar bears have adapted to living on ice and being able to withstand the cold weather. Now that the climate is changing at a fast pace, polar bears are losing their land because its melting, leaving them with no place to walk, sleep and taking away their way of hunting prey. (polar bears international, 2015) This is all happening so fast that there is no way polar bears will be able to adapt to the new environments, causing extinction. The arctic is warming twice as fast as the rest of the world is due to the build up of greenhouse gases in the atmosphere, making it a problem happening very rapidly. (Bagley, 2015) Temperatures in the Arctic region have risen 7 degrees Fahrenheit over the last half century. (Bagley, 2015) Population among polar bears has decreased up to 40% in some areas. (Bagley, 2015) With the climate getting warmer, ice is melting earlier every spring, and takes longer to freeze every winter which is disrupting the feeding and breeding cycles of many different arctic species. (Bagley, 2015) Polar bears have adapted ways to survive in the cold harsh arctic environment including having the ability to cool down their outer skin to keep their vital organs warm when they are submerged in cold water. Though this may help the delay of hypothermia as they have to swim greater distances from ice shelf to ice shelf, that doesn't mean polar bears can swim forever. (Bagley, 2015) One bear that a scientist studied swam 500 miles over nine days, but lost 22% of her body weight, and lost her cub.(Bagley, 2015) Many different scientists have been studying the behaviour of the polar bear to see if it could adapt in any way to survive. Eight U.S scientists made a hypothesis consisting that polar bears could lower their metabolic rates enough to survive as food
Global warming has become a more prominent issue every decade since the mid 1900s. The increased temperatures are leading to substantial ice loss. This loss in ice is causing severe destruction to polar bear habitats and homes and is leading to their extinction. It also is affecting their food supply. Global warming is making it harder for polar bears to repopulate and is causing a decrease in the overall size of each bear. The chemicals associated with global warming are getting into the food chain and eventually into the polar bears themselves. Global warming is causing the extinction of polar bears in the arctic because it’s destroying their homes, decreasing their food supply, is affecting chemicals in the air and in their food, decreasing the average size of the bears, and contributes to a decrease in reproduction.
The polar bear has a long, narrower head and nose, and small ears. The polar bear has coat that appears white but, each individual hair is actually a clear and hollow. This helps the polar bear keep warm. The polar bear's coat helps it blend in with its snowy surroundings, this adaptation helps the Polar Bear hide while hunting. The polar bear's front legs are slightly pigeon-toed, and fur covers the bottoms of its paws. These adaptations help the polar bear keep them from slipping on ice.
The polar regions are most affected and vulnerable to the warming temperatures because the poles are covered in ice. The world’s ice sheets are melting faster than ever and temperatures in the Arctic region are rising twice as fast as anywhere else on Earth according to the NRDC. This will have a serious impact on people, wildlife and plants in that region. The National Climate Assessment has said that “By the year 2100, it 's estimated our oceans will be one to four feet higher, threatening coastal systems and low-lying areas, including entire island nations and the world 's largest cities, including New York, Los Angeles, and Miami as well as Mumbai, Sydney, and Rio de Janeiro”. Polar bears are in great threat as the ice sheets melt because they use the ice to travel across the land and hunt. As the sea-ice platforms move further apart, the swimming conditions become more dangerous. The U.S Geological Survey done by the National Wildlife Federation predicts that by the year 2050, two thirds of all polar bears will disappear. Researcher Bill Fraser has tracked the Adelie penguins in Antarctica and reported the numbers have fallen from 32,000 to only 11,000 over the last 30