The results of three recently-released studies that were not included in the last IUCN Red List assessment add more than 2,050 bears (on average)1 to the official 2015 global polar bear estimate, a point you won’t likely hear next Monday (27 February) from most polar bear specialists, conservation organizations, their cheerleaders and corporate sponsors on International Polar Bear Day.
This means the adjusted 2015 global estimate for polar bears should be about 28,500 (average), a significant increase over the official estimate of 26,500 (average) for 2015 — and an even larger increase over the 2005 estimate of about 22,500 (average)2, despite the dramatic loss of summer sea ice since 2007 that we hear about endlessly.
It is increasingly obvious that polar bears are thriving despite having lived through summer sea ice levels not predicted to occur until 2050 ‚Äì levels of sea ice that experts said would wipe out 2/3 of the world’s polar bears (Amstrup et al. 2007; Crockford 2017a, b).
So when you hear, “Save the polar bears, their future is grim” next week, remember that polar bears are thriving right now because those future predictions were flawed: summer sea ice is not critical habitat for polar bears. Instead of a vacuous “vanishing species” polar bear T-shirt from WWF, buy Polar Bear Facts and Myths for the kids in your life ‚Äì and Polar Bears: Outstanding Survivors of Climate Change for your home or community library. You’ll be glad you did.
Footnotes:
1. Total for all three estimate increases is 2054, or about 2050.
Barents Sea (BS) estimated at 3749 for entire region, up 42% (1109) since 2004 estimate of 2640, based on 42% Svalbard increase determined in 2015 (Norwegian Polar Institute 2015; Crockford 2017b) applied across the region. This is consistent with observations in 2004 that researchers found about three times (2.87) as many bears in the Russian sector than in Svalbard (Aars et al. 2009), and the stated expectation by Norwegian biologists that the population size would continue to increase despite declines in sea ice (Fauchald et al. 2014).
Baffin Bay (BB) estimate 2,826 (95% CI = 2,059-3,593) at 2013 (SWG 2016), up 752.
Kane Basin (KB) estimate 357 (95% CI: 221 – 493) at 2013 (SWG 2016), up 193.
2. USGS polar bear biologists (Amstrup et al. 2007) used a figure of 24,500 for the global population size in 2005 to support their prediction of doom at mid-century that put polar bears on the US Endangered Species List (Crockford 2017a,b). If we use that figure instead of the average of “20,000-25,000” the increase at 2015 (with the amended data) is still a remarkable 16%.
