Arctic Bears
The Melting Arctic's Impact on Its Ecosystem

The polar bear has become the poster child of global warming, but there’s more to the Arctic than ice and polar bears. Beyond these two famous and prominent features of the Arctic environment, there is an entire intricate ecosystem of wildlife and plant life that will be profoundly affected by a prolonged warming trend in the Arctic.

There’s no doubt the Arctic is warming. In fact, this extreme region has warmed faster than any other on earth, with the Arctic temperature increasing three to five times faster than the Earth as a whole over the past 100 years. Climate models predict that the Arctic will become an additional 7 to 12 degrees Fahrenheit warmer during the next century.

Experts predict these rising temperatures are likely to cause the melting of at least half the Arctic sea ice by the end of the century. Melting ice is expected to lead to even higher Arctic temperatures as bright white ice plays a significant role in reflecting the sun’s radiation. As ice melts, more of the dark ocean and land are exposed to absorb the radiation, thus further warming the climate. Research has found that over a major portion of the ice-covered Arctic Ocean, sea ice is 40 percent thinner than it used to be. And some climate models predict that by 2070, there may be no summer ice cover in the Arctic at all.

The disappearance of sea ice is a particularly dire threat to the polar bear, a super specialist in the Arctic environment. Polar bears rely on the ice to hunt seals, their main food source, and also to rest between hunts out on the ice. Trapped, drowning and starving bears have become such a concern that in September 2007, the U.S. Geological Survey (USGS) released a series of studies that led its scientists to conclude that “future reduction of sea ice in the Arctic could result in a loss of two-thirds of the world’s polar bear population within 50 years.” As sad as such a fate for this majestic creature would be, the consequences would extend far beyond the bear. A polar bear decline could trigger what biologists call a “trophic cascade,” or a complete uncoupling of the Arctic food chain.

As much attention as the effects of melting sea ice on polar bears has drawn of late, it is important to understand that the thaw will have immediate effects on everything in the marine food chain, from benthic invertebrates to marine mammals. What will be the fate of the ringed seal, bearded seal, bowhead, beluga, and walrus — all creatures that depend on the ice for habitat or food?

Warming not only affects sea ice, it alters the Arctic’s terrestrial landscape. Melted permafrost means a proliferation of low-lying shrubs. These northern-spreading shrubs establish a new order of plant life, shading out low-growing lichens and plants like ground willow and cotton grass, all favorite foraging items for grazers like caribou. Without their main summer and winter foods, caribou are vulnerable to starvation.

Another species affected by changing Arctic vegetation is the lemming. Drastic changes in its food supply of sedges and mosses, along with a lack of snow tunnels to burrow in, will challenge the survival of these rodents and may cause their populations to crash beyond repair. When lemming numbers drop, so do the numbers of predators like snowy owls and Arctic foxes. Researchers have already observed warning signs in the Arctic fox population in the form of an invasion of red foxes into the traditional range of Arctic foxes.

With a warming Arctic comes an earlier spring and a proliferation of parasitic insects such as flies and mosquitoes. For Arctic dwellers as disparate as caribou and guillemots, a population explosion of insects is at best a nuisance, and at worst, life-threatening. Grazers spend less feeding time and more energy just trying to escape these pests. Arctic-nesting Brunnich’s guillemots in Canada have been such victims of relentless mosquito attack, they have been observed abandoning their nests.

A changed season for insects also has a different effect on some other species of birds, which time their migrations to coincide with insect swells. Northern Alaska dunlins, for example, migrate from Asia and lay their eggs to take advantage of peak insect populations in order to feed their young. Warmer temperatures may cause the insects to hatch earlier, throwing off the carefully timed breeding and nesting season of the dunlins.

With the Arctic experiencing the most rapid and severe climate change on Earth, the plants and animals that have evolved to survive in this extreme habitat come increasingly under threat. Like the canary in the coal mine, the Arctic can serve as our early warning sign of impending climate change. Observing the tumultuous change its inhabitants are experiencing can be a lesson to us about the changes in store for the rest of the world.

  • rwayres

    With climate change,global warming and in resent times the vanishing bee hives should give humans a rough wake up call on what is happing to our planet. Not to leave it up to the science,technology or the other person. We are the science,we are the technology and we are the other person.

  • Mickey Bailey

    To whom it may concern,We are the Problem,ever since Columbus came over to USA,The First Nation People Have been struggling to survive..Inventions,easier way of life,have disrupted Nature,abusing the people animals…Humans r Gluttons…More is better,never think of anyone or thing other then there selfs…The Animals r a lot smarter, than we r.. they will figure it out if we leave them alone…Man has messed everything up all over the world,by building &building more cars,houses,factorys,destroying everything in there path, to Obtain Grandiosity…Look what i got,or what i accomplished,Never trying to help anyone or thing out..Worrying about SELF…So look in the MIRROR, What do u SEE?
    The Answers R inside of u,if u know how to DIE of SELF…

  • dan doujs

    what is the matter with you people, your basic message is, save the earth,kill the humans, get over the fact that the earth might be warming up, bitching about it on blogs isnt going to do anything to help,

  • loittle

    they need to be saved they don’t need to die

  • lenny the polar bear

    i eat seels

  • lenny the polar bear

    free my polar bear peeps

  • shirley

    we need to stop polluting this world because we are going to cause a huge damage

  • http://politics-news.omicidio.net/qa-ask-your-questions-on-polar-politics/ Q&A: Ask your questions on polar politics | Politics News

    [...] considered a frigid wasteland, the Arctic is melting faster than any other region on earth and revealing its hidden treasures in the process, from oil to new shipping [...]

  • http://politics-news.omicidio.net/tune-in-online-radio-show-on-polar-politics/ Tune in: Online radio show on polar politics | Politics News

    [...] considered a frigid wasteland, the Arctic is melting faster than any other region on earth and revealing its hidden treasures in the process, from oil to new shipping [...]

  • kristine

    I love this earth and I love these animals, I will not give up on them and that is my choice!

  • patrick

    polar bears are helpless. there is nothing they can do about this;but there is something we can do to help! So if we are the only ones who can stop it, why don’t we?

  • frenuchsk

    ice bear also come wen i was on the ice in Russia. i see bear up close wen i climbed up ice berg i was with friends hike through icy land to get to Siktyakh to my home town of Nordvik. Nanuuk smell me and friend so we had to scare it away. we were afraid it might be hungry so i scared. You never now if the bear wil attack. do not run away. That is sign of weakness. Hungry male only wil chase you until he gets his food. you must scare polar bears away and they wil not think of you as prey but as a thret. Anyways on our long trek north we see another polar bear a macherd devuchka and her yung one. In this case momma want to scare us away so instead of scare her we run in the other directon. i learn English from my father who is speaking for democrats in our country. i hope my ritting is correct. Sorry if it is not.it took me 3 years to learn the langaug. North Russia is currently funding wild life like polar bears to help there species recover from ice lost.

  • sophie

    we need to change our ways right now

  • Bree

    WE NEED TO HELP THESE POOR ANMAILS!!
    OR ITS GOING TO BE BADD!!

  • Jill

    These animals need our help right now, and we are all to blame for this. This is bad. Recycle. turn off lights during the day. solar power. wind power.

    boo to fossil fuels!!

  • alexzandria

    i love polar bears so much i am doing a project and i have to pick a animal so i picked a polar bear anyways
    i just wanted to say i love polar bears anyways i better get started on my project so i can turn it in on time lol bye:)

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  • Joe

    i live in Mongolia and grew up in north central US winters. I can tell you from bitterly cold experience, we need global warming. The many benefits far outweigh the disadvantages. Besides, developing countries such as China fully intend to pour out larger and larger amounts of greenhouse gasses just as western countries plan to throttle their economies with greenhouse emission standards. Large predators such as Polar bears eat too many fish. Fewer predators shouldn’t hurt in a hungry world where a large portion of humanity doesn’t have enough to eat. We shouldn’t apologize for being at the top of the food chain and using it to manage animal populations efficiently and to their health. I expect a storm of hostile politically correct mail response. Please don’t disappoint me.

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  • Valeriya

    To Joe:
    Yes half of our population is starving but its not due to our inability to produce food. But due to our greadeness, political/economical systems, and in most cases pollution. We polluted so many rivers, lakes and dried out seas that fish that we are suppose to eat can just survive or re-establish its own populations. So not only we compromising our food for survival but we also taking it away from animals who just happen to share food resources wit us. And if China decides to do something, do we really like blind sheep gonna follow them? In my opinion China eats a thousands times more fish than a couple hundreds of polar bears, or what ever there numbers are. We shouldn’t apologize for being on top, but we should apologize to everyone undeveloped world for showing an awfully terrible example of life, natural ecosystems for destroying them and to our future children who will have to deal with consequences of a genetically modified, polluted and destroyed world we created. I hope my, in my opinion politically correct, e-mail didn’t disappoint your expectations.

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