Hungry polar bears stalk the Siberian village of Amderma, population 350, in August 2015. Photo: WWF Russia / The Siberian Times

20 January 2015 (Polar Bear Specialist Group) – The present table was discussed during late fall and early winter 2014, and agreed upon by the group on 20 January 2015. This status table will be updated whenever there is new information available that is considered credible and valid by the group.

This year's status table includes two new columns with metrics for sea ice change:

  1. Change in date of spring sea ice retreat and change in date of fall sea ice advance (days per decade) over the period 1979-2014. Each year the area of sea ice reaches a maximum in March and a minimum in September.  In order to measure the timing of the seasonal change in sea ice, we find the date each spring when the area of sea ice has dropped to a specific threshold and the date each fall when the area has grown back to that same threshold. The region-specific threshold is halfway (50%) between the mean March sea-ice area and the mean September sea-ice area over the period 1979-1988 for each subpopulation region.
  2. Change in summer sea ice area (percent change/decade, June 1 – October 31) relative to the average summer sea ice area during 1979-1988. Sea ice area was calculated as the sum, over all grid cells with >15% sea ice concentration, of the grid cell area multiplied by the grid cell sea ice concentration.

Click the subpopulation hyperlink and more information will appear.

Download the status table (PDF 98.7 kB)

Subpopulation Size Trend Sea ice metrics Human-caused removals 2010–2014
Estimate / Year Method Relative to historic level Current (approx. 12-yr Change in spring ice retreat / Change in fall ice advance (days per decade) Change in summer sea ice area (percent change per decade) 5-yr mean Last year
95% CI (approx. 25-yr past) period centered on present) Potential Actual Potential Actual
Arctic Basin Unknown Data deficient Data deficient -0.4 -6.7
Baffin Bay 1546 2004 PVA Data deficient Declining -1.40385 -18.9 144 149 132 137
690-2402 (Based on physical capture-recapture estimate from 1998)
Barents Sea 2644 2004 Distance sampling Data deficient Data deficient -0.68595 -16 NA 2 NA 3
1899-3592
Chukchi Sea Unknown Data deficient Data deficient -0.80952 -18.8 58 30 (U.S.) + approx. 32 (Russia) 58 23 (U.S.) + approx. 32 (Russia)
Davis Strait 2158 2007 Physical capture-recapture Data deficient Stable -0.79381 -19.9 99 99 103 105
1833-2542
East Greenland Unknown Data deficient Data deficient -1.12727 -6.5 62 63 64 65
Foxe Basin 2580 2009/10 Distance sampling Not reduced Stable -0.91379 -14.2 97.8 104 71 85
2093-3180
Gulf of Boothia 1592 2000 Physical capture-recapture Not reduced Stable -0.83133 -12.2 60 58 58 52
870-2314
Kane Basin 164 1994-1997 Physical capture-recapture Data deficient Declining -1.28571 -12.2 11 6 11 5
94-234
Kara Sea Unknown Data deficient Data deficient -1.21053 -18.6 NA NA
Lancaster Sound 2541 1995-1997 Physical capture-recapture Data deficient Data deficient -1.09804 -7.7 93 84.8 102 83
1759-3323
Laptev Sea Unknown Data deficient Data deficient -1.26154 -14.7 NA NA
M'Clintock Channel 284 2000 Physical capture-recapture Reduced Increasing -0.67241 -9 3 3 3 3
166-402
Northern Beaufort Sea 980 2006 Physical capture-recapture Not reduced Stable -1.75758 -5.9 65 37.4 65 43
825-1135
Norwegian Bay 203 1997 Physical capture-recapture Data deficient Data deficient -0.30233 -2.3 4 2.2 4 3
115-291
Southern Beaufort Sea 907 2010 Physical capture-recapture Reduced Declining -1 -20.5 76 35.6 73 42.3
548-1270
Southern Hudson Bay 951 2012 Distance sampling Not reduced Stable -0.7561 -11.4 60 62 60 56
662-1366
Viscount Melville Sound 161 1992 Physical capture-recapture Data deficient Data deficient -0.63514 -6.1 5.6 7 6 7
121-201
Western Hudson Bay 1030 2011 Distance sampling Reduced Stable -1.44444 -16.3 22.6 23.2 28 32
754-1406

 

Summary of polar bear population status per 2014

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