Polar bear swimming in the Beaufort Sea, near Tuktoyaktuk, NWT, Canada April 27, 2009. It’s April but the sea here is ice-free. The bears can swim for long distances, but prefer not to as it uses up vital energy resources. They can only hunt and mate on the sea ice, without it, their survival is threatened

Polar bear swimming in the Beaufort Sea, near Tuktoyaktuk, NWT, Canada April 27, 2009. It’s April but the sea here is ice-free. The bears can swim for long distances, but prefer not to as it uses up vital energy resources. They can only hunt and mate on the sea ice, without it, their survival is threatened
Photo Credit: A.E.Derocher - Univ.Alberta

Climate change: Are polar bears doomed?

All populations could decline by 30 percent by 2050

A just released report has cast even more concern about the future of the polar bear survival as a species.

The international study involved research scientists from the US, Canada, and Norway, was published this month in the Royal Society science journal Biology Letters and is entitled Conservation status of polar bears (Ursus maritimus) in relation to projected sea-ice declines”.(full study HERE)

© Eric Regehr et al- Biology Letters

Illustration above: The four polar bear ecoregions and 19 subpopulations. Convergent ecoregion: East Greenland (EG) and Northern Beaufort Sea (NB). Divergent ecoregion: Southern Beaufort Sea (SB), Chukchi Sea (CS), Laptev Sea (LP), Kara Sea (KS) and Barents Sea (BS). Archipelago ecoregion: M’Clintock Channel (MC), Viscount Melville Sound (VM), Norwegian Bay (NW), Kane Basin (KB), Lancaster Sound (LS) and Gulf of Boothia (GB). Seasonal ecoregion: Western Hudson Bay (WH), Foxe Basin (FB), Baffin Bay (BB), Davis Strait (DS) and Southern Hudson Bay (SH). The Arctic Basin (AB) subpopulation likely has few year-round resident polar bears and was excluded from analyses .

Noting that sea-ice is critical to the bears survival, the study analyzed sea ice data from 1979-2014. They then ran models based on three scenarios over three generations of bears and found that polar bear population could decline by 30 to 80 percent by mid century.

Another recent study by the University of Washington  published in the science journal The Cryosphere came to similar conclusions.

It said that the polar bears “ dependence on sea-ice means that climate warming poses the single most important threat to their persistence”.

University of Washington study/video (facebook)

The studies found that sea ice is retreating 3 to 9 days earlier and forming later by 3 to 9 days over every ten years and in every area for the 19 bear populations across the circumpolar region and Hudson Bay.  That meant a total of almost two months less of sea ice over the study period.  By mid-century that will mean an additional seven or so ice-free weeks for the bears.

The bears not only need the ice to feed, but also to mate and raise young.

Autumn 2012, a bear walks along the shore of Hudson Bay waiting for ice to form. Longer periods on land means longer periods of fasting, and of negative interactions with human populations.
Autumn 2012, a bear walks along the shore of Hudson Bay waiting for ice to form. Longer periods on land means longer periods of fasting, and of negative interactions with human populations. © A.E. Derocher, Univ Alberta

RCI-global warming- polar bears energy cost of swimming

Another study last year of the polar bear population in the Beaufort Sea showed that loss of sea-ice in 2005-2006 resulted in a sudden decline in that population of about 40%. That study was published in the science journal Ecological  Applications. (abstract and links HERE)

The total population of polar bears is currently estimated at around 25,000.

additional information- sources

Tagged with: , , , , , ,
Posted in Animals, Environment, International, Science and Technology

Do you want to report an error or a typo? Click here!

@*@ Comments

Leave a Reply

Your email address will not be published. Required fields are marked *

 characters available

Note: By submitting your comments, you acknowledge that Radio Canada International has the right to reproduce, broadcast and publicize those comments or any part thereof in any manner whatsoever. Radio Canada International does not endorse any of the views posted. Your comments will be pre-moderated and published if they meet netiquette guidelines.

Netiquette »

When you express your personal opinion in an online forum, you must be as courteous as if you were speaking with someone face-to-face. Insults and personal attacks will not be tolerated. To disagree with an opinion, an idea or an event is one thing, but to show disrespect for other people is quite another. Great minds don’t always think alike—and that’s precisely what makes online dialogue so interesting and valuable.

Netiquette is the set of rules of conduct governing how you should behave when communicating via the Internet. Before you post a message to a blog or forum, it’s important to read and understand these rules. Otherwise, you may be banned from posting.

  1. RCInet.ca’s online forums are not anonymous. Users must register, and give their full name and place of residence, which are displayed alongside each of their comments. RCInet.ca reserves the right not to publish comments if there is any doubt as to the identity of their author.
  2. Assuming the identity of another person with intent to mislead or cause harm is a serious infraction that may result in the offender being banned.
  3. RCInet.ca’s online forums are open to everyone, without regard to age, ethnic origin, religion, gender or sexual orientation.
  4. Comments that are defamatory, hateful, racist, xenophobic, sexist, or that disparage an ethnic origin, religious affiliation or age group will not be published.
  5. In online speak, writing in ALL CAPS is considered yelling, and may be interpreted as aggressive behaviour, which is unpleasant for the people reading. Any message containing one or more words in all caps (except for initialisms and acronyms) will be rejected, as will any message containing one or more words in bold, italic or underlined characters.
  6. Use of vulgar, obscene or objectionable language is prohibited. Forums are public places and your comments could offend some users. People who use inappropriate language will be banned.
  7. Mutual respect is essential among users. Insulting, threatening or harassing another user is prohibited. You can express your disagreement with an idea without attacking anyone.
  8. Exchanging arguments and opposing views is a key component of healthy debate, but it should not turn into a dialogue or private discussion between two users who address each other without regard for the other participants. Messages of this type will not be posted.
  9. Radio Canada International publishes contents in five languages. The language used in the forums has to be the same as the contents we publish. The usage of other languages, with the exception of some words, is forbidden. Messages that are off-topic will not be published.
  10. Making repetitive posts disrupts the flow of discussions and will not be tolerated.
  11. Adding images or any other type of file to comments is forbidden. Including hyperlinks to other websites is allowed, as long as they comply with netiquette. Radio Canada International  is in no way responsible for the content of such sites, however.
  12. Copying and pasting text written by someone else, even if you credit the author, is unacceptable if that text makes up the majority of your comment.
  13. Posting any type of advertising or call to action, in any form, to Radio Canada International  forums is prohibited.
  14. All comments and other types of content are moderated before publication. Radio Canada International  reserves the right to refuse any comment for publication.
  15. Radio Canada International  reserves the right to close a forum at any time, without notice.
  16. Radio Canada International  reserves the right to amend this code of conduct (netiquette) at any time, without notice.
  17. By participating in its online forums, you allow Radio Canada International to publish your comments on the web for an indefinite time. This also implies that these messages will be indexed by Internet search engines.
  18. Radio Canada International has no obligation to remove your messages from the web if one day you request it. We invite you to carefully consider your comments and the consequences of their posting.

*

One comment on “Climate change: Are polar bears doomed?
  1. Meme Mine69 says:

    Polar bears used to be called Yellow bears upon settlement of N. America as they held their summer coat longer and were as far south as the US Canada border.
    The largest populations are in Churchill Manitoba’s municipal dump.

    Now do you see how corrupt CBC is?