I was in the process of writing about something else last week when I came across a tidbit of information that, on closer examination, turned out to be part of a much bigger issue that I thought should be documented.
The story involves some machinations behind the scenes of the international Polar Bear Specialist Group, the “PBSG,” that you might find rather astonishing – and which may have implications for the various on-going battles about the polar bear’s conservation status.
A lone polar bear walking on ice [Kathy Crane (NOAA) photo].
We’ll call this a metaphor for the expulsion of Mitch Taylor from the PBSG,
after the Group switched from emphasizing unregulated over-hunting
as the primary threat to polar bears to global warming.
I was researching the history of polar bear conservation status in the international arena – that is, how, when and why (since 1965) the polar bear has been listed by the IUCN (International Union for Conservation of Nature and Natural Resources – or as it calls itself, the World Conservation Union) in its famous Red Data Book of the world’s rare and endangered animals.
It turns out that by the time of the first international meeting of polar bear biologists in 1965 – before the Polar Bear Specialist Group (PBSG) had even been formally chartered and thus, before it was associated with the IUCN – the polar bear was listed in the IUCN’s Red Book (Anonymous 1966, 68, 70) as Vulnerable.
Polar bears were down-graded from a Vulnerable rating to Lower Risk – Conservation Dependent in 1996, after the IUCN revamped its listing criteria (Derocher et al. 1998:45). It seems that by 1993, polar bear biologists had what they considered a reasonable estimate of the global population (about 21,470-28,370 (Wiig et al. 1995), more on the history of these estimates here ). And with that estimate, it appeared that polar bears no longer qualified as Vulnerable under the new IUCN criteria, as I explain below.
According to the revamped IUCN rules for 1996, there were five criteria to be evaluated in establishing whether a species is Critically Endangered, Endangered, or Vulnerable for the IUCN Red List. By the admission of the PBSG member tasked with this assessment on behalf of the Group (Øystein Wiig, Norway), the polar bear qualified for none of them (Wiig, reported in Derocher et al. 1998:45-46), which he summarizes as follows:
Criterion A. Declining population – “Overall, the number of polar bears is thought to be stable or increasing slowly, therefore Criterion A does not apply.”
Criterion B. Small distribution size – “The species has a larger distribution than 20,000 square km, therefore Criterion B does not apply.”
Criterion C. Small population size – “Based on a minimum total population of 21,000 polar bears (Wiig et al. 1995), the number of mature animals might be less than 10,000. A continuing decline does not occur, therefore, Criterion C does not apply.
Criterion D. Population very small or restricted – “The population estimate is larger than 1,000 individuals and the population has a circumpolar distribution, therefore, Criterion D does not apply.”
*Conclusion: “The polar bear does not qualify for any of the criteria of Critically Endangered, Endangered or Vulnerable and is therefore a Lower Risk taxon.” [formally, Lower Risk: Conservation Dependent]
However, this up-grade in the status of the polar bear did not appear to make the PBSG biologists very happy. You’d think these guys [and the core group were all men during this period – this situation did not change until 2009, when Elizabeth Peacock from Nunavut, Canada, joined PBSG] would have been ecstatic that the protection measures enacted in the 1970s had worked so well.
But by 2006, the polar bear had been up-graded back to Vulnerable at the recommendation of the PBSG (Aars et al. 2006:61 and the Red List).
Curious turn of events, that. How and why did the polar bear move from being a IUCN Lower Risk* taxon in 1996 – because they were doing so well – back to a Vulnerable taxon in 2006, after only 10 years? [*in 2001, renamed Least Concern]
It is important, in my opinion, to understand how and why this turn-about happened because there may be implications for the various on-going battles about the polar bear’s conservation status.