Abundant polar bear habitat across the Arctic at the start of winter

January is the first month of the Arctic winter, the season when most polar bears really struggle to find enough to eat.

Polar bears feeding_Shutterstock_sm

Here is what the sea ice looked like around the Arctic at the end of this month.

masie_all_zoom_4km 2019 Jan 31

Compare to last year:

masie_all_zoom_4km2018jan29

And the year before that (2017):

masie_all_zoom_4km2017jan26

A closer look at conditions in Canada and Alaska:

seaicecanada2019jan31

Compared to last year:

seaicecanada2018jan31

And the year before that (2017), where there was much less ice in the Gulf of St. Lawrence:

seaiceextentcanada2017feb3_cis

In contrast, there has recently been lots of ice compared to conditions in eastern Canada at 31 Jan 2010:

seaice2010labrador31january_masie

Further east, north of Norway, Barents Sea ice has expanded remarkably over the last few months: barentsseaiceextent2019jan31_nis

Here is what polar bear specialist Andrew Derocher had to say about the state of the ice in the Barents Sea:

Derocher is continuing to pretend that the small area of southeastern Svalbard where he once did some field work is critical denning habitat for Barents Sea bears and to pretend he doesn’t know where alternative sites are available. He sang the same song last year about this time. I’ve fixed his sea ice chart for him, see below.

Derocher 2019 Jan 31 on Svalbard denning areas marked

I know he knows that Franz Josef Land is a denning refugium because he co-authored one of the papers that points out the known alternative denning areas in Franz Josef Land and the Barents Sea pack ice around it (Andersen et al. 2012, see also Aars 2015; Aars 2018; Aars et al. 2017; Andersen and Aars 2016; Wiig 1998).

barentsseaice2012_jan31_nisfromarchive

Polar bear specialist Jon Aars found three times as many polar bears in the Russian portion of the Barents Sea as around Svalbard in 2004 (Aars et al. 2009), which means that denning in Svalbard is much less important to the entire population than Derocher implies. Recent evidence that shows Svalbard bears are thriving despite much less ice than existed in the 1980s (Aars 2018) make Derocher and his message of doom look foolish and unprofessional.

References

Aars, J. 2015. Research on polar bears at Norwegian Polar Institute. Online seminar (‘webinar”), January 14. pdf here.

Aars, J. 2018. Population changes in polar bears: protected, but quickly losing habitat. Fram Forum Newsletter 2018. Fram Centre, Tromso. Download pdf here (32 mb).

Aars, J., Marques,T.A, Lone, K., Anderson, M., Wiig, Ø., Fløystad, I.M.B., Hagen, S.B. and Buckland, S.T. 2017. The number and distribution of polar bears in the western Barents Sea. Polar Research 36:1. 1374125. doi:10.1080/17518369.2017.1374125

Aars, J., Marques, T.A., Buckland, S.T., Andersen, M., Belikov, S., Boltunov, A., et al. 2009. Estimating the Barents Sea polar bear subpopulation. Marine Mammal Science 25: 35-52.

Andersen, M. & Aars, J. 2016. Barents Sea polar bears (Ursus maritimus): population biology and anthropegenic threats. Polar Research 35: 26029.

Andersen, M., Derocher, A.E., Wiig, Ø. and Aars, J. 2012. Polar bear (Ursus maritimus) maternity den distribution in Svalbard, Norway. Polar Biology 35:499-508.

Wiig Ø. 1998. Survival and reproductive rates for the polar bears at Svalbard. Ursus 10:25–32.

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