Saturday, 17 December 2016

There are none so blind....

A couple of days ago, I was chatting to a friend in our local watering hole - Yates' in High Wycombe, Buckinghamshire, UK. I'd been telling him how BBC documentaries had become un-watchable for me, mainly because of the constant and intrusive background music."Don't you watch Attenborough?" he asked "Now there's a guy knows what he's talking about."  I nearly choked on my beer, but said nothing. "It's really getting bad in the Arctic - the polar bears are becoming extinct". I asked why that was. "The ice is melting, and the bears can't catch the seals they feed on". "What do the bears eat in the summer, when there's no ice?" I asked innocently. "They live on the body fat they got in the winter, from eating seals in the winter", he replied. I followed up with a low blow - "Where are the seals in the summer?". "I don't know, on the land, I expect". I had him on the ropes - "Where are the bears in the summer?". He pondered a moment - "they must be on the land too?".

"Then what's the problem - seals on land, bears on land - bears catch seals, bears eat seals, period?". "It's not as simple as that" he parried. "Why is that?". "You're not an expert!" he said. "I don't need to be an expert, just be able to use my brain and think!", He was silent. "You'll be telling me next that penguins in the Antarctic need the ice to catch fish?", His eyes showed a glimmer of triumph - "Yes, they do!". The coup de gras from me "How do they catch fish in the summer, when there's no ice?". He was on the ropes again, and getting desperate "This argument is getting nowhere!".

He just wouldn't see that his "factual" documentaries were only telling half the story, pushing a message of starvation and extinction, climate change and global warming; in fact pushing against the truth. I didn't bother pointing out that polar bears are omnivores, and will eat anything - rotting whale carcasses, fish (yes - they can catch fish!), berries, small mammals, leaves and grass. We still chat regularly. I don't bring up any contentious subjects, and I think he's relieved I don't.

UPDATE: In case anyone thinks I'm talking out of my posterior, here's some current research debunking the idea that reduction in Arctic ice will spell doom for the iconic polar bear:

Demographic and traditional knowledge perspectives on the current status of Canadian polar bear subpopulations 
Subpopulation growth rates and the probability of decline at current harvest levels were determined for 13 subpopulations of polar bears (Ursus maritimus) that are within or shared with Canada based on mark–recapture estimates of population numbers and vital rates, and harvest statistics using population viability analyses (PVA). Aboriginal traditional ecological knowledge (TEK) on subpopulation trend agreed with the seven stable/increasing results and one of the declining results, but disagreed with PVA status of five other declining subpopulations. The decline in the Baffin Bay subpopulation appeared to be due to over-reporting of harvested numbers from outside Canada. The remaining four disputed subpopulations (Southern Beaufort Sea, Northern Beaufort Sea, Southern Hudson Bay, and Western Hudson Bay) were all incompletely mark–recapture (M-R) sampled, which may have biased their survival and subpopulation estimates. Three of the four incompletely sampled subpopulations were PVA identified as nonviable (i.e., declining even with zero harvest mortality). TEK disagreement was nonrandom with respect to M-R sampling protocols. Cluster analysis also grouped subpopulations with ambiguous demographic and harvest rate estimates separately from those with apparently reliable demographic estimates based on PVA probability of decline and unharvested subpopulation growth rate criteria. We suggest that the correspondence between TEK and scientific results can be used to improve the reliability of information on natural systems and thus improve resource management. Considering both TEK and scientific information, we suggest that the current status of Canadian polar bear subpopulations in 2013 was 12 stable/increasing and one declining (Kane Basin). We do not find support for the perspective that polar bears within or shared with Canada are currently in any sort of climate crisis. We suggest that monitoring the impacts of climate change (including sea ice decline) on polar bear subpopulations should be continued and enhanced and that adaptive management practices are warranted.
The researchers point out that:
Polar bears evolved from a common ancestor with the brown bear. The range of estimates for the age of polar bears as a species ranges from 4 million years based on deep nuclear genomic sequence data from both paternal and maternal linages (Miller et al. 2012) to 120 thousand years based on the mitochondrial genome (matrilineal) (Lindqvist et al. 2010). If polar bears have existed for the last 4 million years, they would have emerged during the mid-Pliocene approximately 1.25 million years before the onset of northern hemisphere glacial cycles (Bartoli et al. 2005). If polar bears emerged any time prior to or during the previous glacial cycle, they would have persisted through the Eemian interglacial period. During the Eemian interglacial, mean annual temperatures were 4°C warmer than the current interglacial (Holocene) for northern latitudes (Müller 2009), and some northern locations reached temperatures as high as ~7.5°C warmer than the mean temperature for the same area over the last thousand years (Dahl-Jensen et al. 2013). Both scenarios suggest that polar bears are able to mitigate impacts from sea ice decline to an extent not fully exhibited in modern times. Currently, the IPCC predicts globally averaged temperatures to warm ~2°C by 2100 and considers warming of ~4°C by 2100 to be possible although unlikely (Intergovernmental Panel on Climate Change 2013). Reduction in the heavy multiyear ice and increased productivity from a longer open water season may even enhance polar bear habitat in some areas (Stirling and Derocher 1993, 2012; Derocher et al. 2004; Rode et al. 2014). The majority of Canada's polar bears inhabit the Canadian Arctic archipelago (Obbard et al. 2010), where 5 of 13 subpopulations are currently and historically ice-free in late summer and early fall (Lunn et al. 2002; Aars et al. 2006; Obbard et al. 2010). Given the persistence of polar bears through the current and previous interglacial periods, and their ability to accommodate extended retreats onshore and based on the empirical observations of climate and sea ice change (S7), it seems unlikely that polar bears (as a species) are at risk from anthropogenic global warming. However, some subpopulations may experience diminished range, reduced productivity and subsequent decline in numbers if sea ice declines occur as predicted (Stirling and Derocher 1993, 2012; Derocher et al. 2004). While there are many projections of climate change that suggest a nearly ice-free Arctic to occur in the warmer months (i.e., September) (IPCC 2007, 2013, Durner et al. 2009; Amstrup et al. 2010; Mahlstein and Knutti 2012; Overland and Wang 2013), there are currently no global climate model (GCM) projections of climate change that suggest a totally ice-free Arctic in any season or month.
.... so there.

 I'll diversify for a moment, because I've never posted anything personal, or connected with where I live. Wycombe is a somewhat "frayed around the edges" town in the Chiltern Hills, designated an "Area of Outstanding Natural Beauty". Here's Yates' pub - well-managed, good cheap food, good beer, relaxed, friendly and hard-working staff, and a correspondingly relaxed clientèle.
Yates', Frogmore, High Wycombe

This is Wycombe High Street, a pale imitation of what it might have been if the local borough council had constrained development and preserved several much older shops and houses.
High Wycombe High Street

There's a street-market on Tuesday, Friday and Saturday. High Wycombe borough was originally "Chepping Wycombe", Chepping being a corruption of the Old English "Ceapen" meaning a town market. I can't find a pic of the whole market, but here's a colourful corner, situated centre-right in the pic above.
Wycombe market - a historical remnant of a prosperous past.

And a couple from the surrounding beechwoods and countryside.
An ancient "dyke" or boundary ditch in the beechwoods about 10 miles from Wycombe.

Bluebell carpet in the spring

Picture-postcard windmill on a windy ridge.
That'll do!

1 comment:

  1. Yeah those White Bears manage to survive decades of poaching too.

    Polar Bears, eat better when the Sea Ice melts back partly in the late Springtime.This make it easier for Seals to make those breathing holes,where Bears wait around for a seal to show up.That is the part of the year,they get most of the calories for the year.