Polar Bears Booming?

  • Date: 09/01/13
  • Susan J. Crockford, Polar Bear Science

This afternoon I came across some startling information. There are now 22,600-32,000 polar bears worldwide, when tallied by nation. This is a big change from the 20,000-25,000 that has been touted as the global polar bear population since 2005.

According to a dynamic summary report on the home page of theIUCN/SSC Polar Bear Specialist Group website  called State of the Polar Bearthere are now 22,600-32,000 polar bears worldwide, when tallied by nation.

Here are the numbers, by nation, listed in the State of the Polar Bearsummary report (see map below):
Canada                              13,300-17,500
USA                                   1,200-1,800
Russia                               2,700-4,800
Norway                             1,900-3,600
Greenland
(Denmark)                        3,5000-4,400
Total                            22,600-32,000

The “Nations” page of the Polar Bear Specialist Group’s “State of the Polar Bear,” a dynamic summary that can be launched from the home page of the IUCN PBSG  http://pbsg.npolar.no/en/dynamic/app/ [published Oct. 15, 2012] Click to enlarge.

The “Nations” page of the Polar Bear Specialist Group’s “State of the Polar Bear,” a dynamic summary that can be launched from the home page of the IUCN PBSG website, http://pbsg.npolar.no/en/ [published Oct. 15, 2012] Click to enlarge.

This is a big change from the 20,000-25,000 that has been touted as the global polar bear population since 2005 (see Aars et al. 2006; Obbard et al. 2010) and my post on polar bear population estimates.
[updated Jan. 9 2013 at 8:20 PST, see end of post]

I found nothing to explain the difference in these two estimates in theState of the Polar Bear feature – or elsewhere on the PBSG website. Indeed, the “population status” page of the PBSG website still says: “The total number of polar bears worldwide is estimated to be 20,000 – 25,000.”

In the State of the Polar Bear feature, there is a “subpopulations” map where  population estimates are given for each of the 19 recognized subpopulations. Surprisingly, 7 subpopulations are given an estimate of 0 (that’s zero). Greenland, all of Russia, and Norway have no estimates given on the subpopulation map. These three countries cover more than half of the Arctic! However, these same countries are given credit for 8,100-12,800 on the population-by-Nations page. [In addition, two Canadian subpopulations - Foxe Basin and Viscount-Melville – also get a zero on the subpopulations page while the total for Canada on the population-by-Nations page is substantial]

I have never seen an estimate of 22,600-32,000 for polar bears given before – where did these numbers come from?

One explanation is that despite the PBSG insisting that it has no valid population estimates for Russia, Greenland and Norway, it must have. If it didn’t, why produce a map listing polar bear populations by nation in the first place?

Suggesting that Russia, Greenland and Norway have no polar bears (i.e. zero) would be patently untrue. So the PBSG had to provide polar bear population estimates for these three nations.

Apparently, the PBSG were confident enough of their population estimates for Russia, Greenland and Norway to commit these numbers to their “State of the Polar Bear” summary that’s featured on the front page of their website.

If there could be as many as 32,000 polar bears worldwide, why have we not heard of this before? Is this another example of data being kept secret?[see previous discussion here and here]. Or is something else going on?

Full story

Update: The 32,000 population estimate for polar bears is not an error due to counting overlapping territories twice