Andrew Wetzler's Blog
Planet Gore Replies
August 8, 2008
Posted by Andrew Wetzler in Saving Wildlife and Wild Places , Solving Global Warming
Greg Pollowitz has posted a reply to my critique of his post on the discovery of 125,000 western lowland gorillas in the Republic of Congo. In his original post, Pollowitz seemed to argue that this discovery should undermine our confidence in predictions of declining polar bear populations due to sea ice loss. Expanding on what was some pretty thin gruel, he now writes:
I'm saying that up until a few days ago, the settled science was that there were only 50,000 gorillas left in the world. I'm saying that millions of dollars have been spent in a way that might have gone to better use, for both the gorillas, and more importantly, for the humans that live in Africa. I'm saying that the WCS, when helping to look for polar bears "studied 28 years of satellite images of sea ice and contributed key data to a study by the U.S. Geological Survey (USGS) that helped inform the USFWS decision." I'm saying that maybe the WCS should stop looking at their computers and, like they did in Africa, actually try to count the polar bears with something other than a 50-year ice model.
But look, this is still an incredibly weak argument. The gorilla discovery (just like the discovery of vast antelope herds in the Sudan that Pollowitz also cites) is fundamentally a situation in which a new population of wildlife was discovered in suitable habitat that hadn’t been surveyed by biologists. In the case of polar bears, it’s the habitat itself that’s vanishing. The listing of polar bears is based on a pretty simple syllogism—Arctic sea ice is disappearing and will likely be entirely gone by the end of the century; polar bears need sea ice to survive; therefore, polar bears are endangered. Make no mistake, there are mountains of evidence to support this conclusion, but the logic is not hard to understand.
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Comments
Ted Cunningham — Aug 10 2008 12:45 AM
That is an impressive "mountain of evidence". "Giardiasis in Pinnipeds"- are you kidding me?
1. Over the next 92 years, you don't think the bears will figure out a way to adapt? Maybe move to one of the land masses of the northern continents or Greenland?
2. How are you (or a climate scientist) able to predict weather trends out 92 years? Does it bother you at all to look at the past few decades of temperature change, and extrapolate that out for the next 9 decades?
Andrew Wetzler — Aug 10 2008 10:39 AM
Ted:
Under the Endangered Species Act, one of the factors that the Fish and Wildlife Service must consider is the degree to which "disease and predation" may be contributing to a species risk of extinction. The article you reference (Measures and Olson 1999) was used in the Fish and Wildlife Service's final listing decision as follows:
"Whether polar bears are more susceptible to new pathogens due to their lack of previous exposure to diseases and parasites is also unknown. Many different pathogens and viruses have been found in seal species that are polar bear prey (Duignan et al. 1997, p. 7; Measures and Olson 1999, p. 779; Dubey et al. 2003, p. 278; Hughes-Hanks et al. 2005, p. 1,226), so the potential exists for transmission of these diseases to polar bears. As polar bears become more nutritionally stressed, they may eat more of the intestines and internal organs of their prey than they presently do, thus increasing potential exposure to parasites and viruses (Derocher et al. 2004, p. 170; Amstrup et al. 2006b, p. 3). In addition, new pathogens may expand their range northward from more southerly areas under projected climate change scenarios (Harvell et al. 2002, p. 60). A warming climate has been associated with increases in pathogens in other marine organisms (Kuiken et al. 2006, p. 322)."
So, yes, it is a part of that "mountain"
-- Andrew
JohnLopresti — Aug 10 2008 01:14 PM
There was an interesting discussion of progressive change in sea temperature recently at a respected Goddard Institute website. The following link is to one contributor who examines the arctic ice winter thinness compared to prior thicker seasonal coverage.
Dan Staley — Aug 11 2008 02:44 PM
you don't think the bears will figure out a way to adapt? Maybe move to one of the land masses of the northern continents or Greenland?
Here: you adapt too. Move into the dense city and find a home.
C'mon! Move! Move to New York! Find a home! Adapt! Adapt, dangit!
Does it bother you at all to look at the past few decades of temperature change, and extrapolate that out for the next 9 decades?
No, as the models include more than just temperature.
Or perhaps you think that, say, models to design airplanes only include the oxygen component of the atmosphere. Or chemical models for medicine only include white blood cells.
Ted Cunningham — Aug 12 2008 03:52 PM
Andrew-
I don't mean to dwell on seals, I swear I picked that paper at random to make my point. I still think it is a mistake to ASSUME that giardiasis in seals will hurt the polar bears. It could be that it will make the seals easier prey, thus providing feasts for the bears, meaning they don't need to consume entrails, also leading to a jump in bear population. There is no evidence to conclude either way. What there is, is supposition in the 'Discussion' section of papers, in which scientists discuss the importance of their data, including their own opinion of the significance of their findings. I've been reading scientific papers for 30 years, I don't recall a single one saying, "this data is unimportant, and does not contribute to our understanding".
Scientists live or die professionally by their ability to get grants to carry out their work. No scientist is ever going to conclude, "this data shows there is no problem', because that will guarantee non-renewal of the grant. I'm not saying scientists commit fraud by saying something "needs further study", and indeed probably most research projects uncover more questions than they answer. But, by considering the further direction of research in your paper's discussion, it becomes easier to get more money for your work. Whether you think that direction is worthwhile or not.
Dan- Not sure what your point is, but thanks for helping me make my point. The polar region is not a simple system, but an incredibly complex, chaotic system. To suppose that we can predict that system for the next 90 years is incredibly arrogant and strains credulity. I'm hoping that both you and Andrew will resist blind acceptance of the suppositions of some very smart, but not clairvoyant scientists, and think independently.
Ted
Jennifer — Aug 13 2008 01:14 AM
Doesn't it bother you that your grandchildren may never see a polar bear? Critics can quack all they want right or wrong (got to love that free speech, regardless), but really FEEL the picture of a lone polar bear trying to raise babies and find food in a home that is literally disappearing under its' feet. If you still have harsh words after that, you have no heart. Please people, be part of the solution.
Ted Cunningham — Aug 17 2008 07:35 PM
Good news for the polar bears! Arctic sea ice is significantly increased this year compared to last. http://igloo.atmos.uiuc.edu/cgi-bin/test/print.sh?fm=08&fd=16&fy=2007&sm=08&sd=16&sy=2008. I'm sure this makes the NRDC happy. Right?