Tag Archives: extrapolation

Accepted sea otter population estimate at 1911 as inaccurate as rejected polar bear estimate for 1960s

Sea otter specialists, without shame or apology, routinely use a benchmark figure of ‘about 2,000’ for the pre-protection population size of the species at 1911 based on extremely limited evidence yet polar bear specialists refuse to accept a benchmark figure for the 1960s despite the existence of eight published estimates made by experts at the time. Sea otters came much closer to extinction than polar bears did and are not out of the woods yet, for reasons that are not entirely understood (Doroff et al. 2021).

Andrew Derocher, 22 February 2022: ‘There never was a population estimate of global abundance in the 1960s.’

Derocher’s statement and those of his colleagues, discussed at length in The Polar Bear Catastrophe That Never Happened, makes them look biased and unprofessional. There is absolutely no rational scientific justification for holding this stance.

Continue reading

Latest global polar bear abundance ‘best guess’ estimate is 39,000 (26,000-58,000)

It’s long past time for polar bear specialists to stop holding out for a scientifically accurate global estimate that will never be achieved and determine a reasonable and credible ‘best guess’. Since they have so far refused to do this, I have done it for them. My extrapolated estimate of 39,000 (range 26,000-58,000) at 2018 is not only plausible but scientifically defensible.

Polarbear1_wikimedia_Andreas Weith photo Svalbard sm

In 2014, the chairman of the IUCN Polar Bear Specialist Group (PBSG) emailed me to say that their global population size number ‘has never been an estimate of total abundance in a scientific sense, but simply a qualified guess given to satisfy public demand.’

In my new book, The Polar Bear Catastrophe That Never Happened, I contend that this situation will probably never change, so it’s time to stop holding out for a scientifically accurate global estimate and generate a reasonable and credible ‘best guess’. Recent surveys from several critical polar bear subpopulations have given us the information necessary to do this.

UPDATE: I have made this a sticky post for a while: new posts will appear below.

Continue reading