BBC perspective on Arviat polar bears – those not included in the last mark-recapture study

In a polite but misleading article today in a BBC magazine (The polar bears are coming to town) about the relationship of polar bears and Inuit in Arviat, Western Hudson Bay, there is no mention of the on-going feud between Nunavut Inuit and Canadian polar bear scientists regarding invasive research.

Churchill_Polar_Bear_2004-11-15 Wikipedia

Nor is there a mention of the fact that according to the most recent research, there has been no trend in sea ice conditions since 2001.

Find Arviat on the map of Western Hudson Bay study area provided by Lunn and colleagues (2013, 2014) in their mark-recapture study report (below) discussed in detail in my last post. Area “A” – where Arviat is located – was not included in the last mark-recapture survey because Nunavut won’t allow invasive research on polar bears.

Lunn et al. 2013, 2014. Map of study area.

Lunn et al. 2013, 2014. Map of study area.

The issue of the invasive research involved in polar bear mark-recapture studies around Churchill, Manitoba (chasing bears with helicopters, drugging them, extracting a tooth, tattooed, and attaching satellite radio collars or ear tags), has been so strenuously objected to by the Inuit of Nunavut that they have refused to allow the necessary field research permits for these activities (previous posts here, here, and here). See also the guest post by Kelsey Eliasson Invasive Research is Alive and Well in Canada

Arviat is in Nunavut and so mark-recapture work was not permitted there in 2011 – which is why Lunn and colleagues could not include those bears in their survey. Lunn et al. did not mention this conflict in their government report (2013) or in the version of it that is destined for publication (2014). They offered no reason why they did not survey in the Nunavut portion of Western Hudson Bay (Area A), which was included in the aerial survey conducted by Stapleton and colleagues (2014) and previous mark-recapture studies.

The author of today’s BBC essay (Irish anthropologist Martina Tyrrell) seems not to know about the invasive research issue or the lack of trend in sea ice conditions revealed in the mark-recapture study report (Lunn et al. 2013), because this is what she said about polar bear visits to Arviat:

“Over the past decade, however, encounters have been on the increase. Camping south of the community in summer is no longer safe, and autumn berry picking – an important subsistence activity usually undertaken by women and children – is now fraught with danger. Bears increasingly wander the streets of Arviat, particularly in late autumn.

At this time of year, regular announcements of bear sightings are made on local community FM radio, schools are sometimes closed early and the usually lively streets are eerily quiet. Halloween trick-or-treating, once so wild and fun-filled, has been all but wiped out, for fear of unwanted encounters not with ghosts or demons but with wandering bears.

What is driving this change in the polar bears’ behaviour?

Many Arviarmiut blame polar bear tourism in neighbouring Churchill – 250km to the south – for encouraging the animals to look for food in human settlements.

But there are other theories. Some Inuit think the bear population in the region is growing. Many scientists, on the other hand, put the blame on habitat loss – according to this theory it’s the desperation of hungry bears facing decreased ice seasons in a rapidly warming Arctic that leads them to approach the town. They have always gathered on the coastline at this time of year, awaiting the formation of the sea ice that is their winter hunting ground, but usually at a greater distance.” [my bold]

Read the rest here.

One of those “theories” is easily refuted by the Lunn et al. report (2013, 2014; Fig. 5): there has been no trend in sea ice breakup or freeze-up of Western Hudson Bay sea ice since 2001. Just the usual year-to-year variation, which can be fairly large:

Lunn et al 2013 breakup freeze up dates marked

[Observations since then have been consistent with that conclusion, for both breakup dates and freeze-up]

Therefore, there may simply be more bears than previously – or Arviat is being visited by more bears as a result of the increased polar bear tourism in Churchill or the increased vigilance of their Polar Bear Alert program. Either way, the sea ice “theory” (see graph below from Lunn et al. 2013) can be ruled out.

[h/t D.K. Johnston]

References
Lunn, N.J., Regehr, E.V., Servanty, S., Converse, S., Richardson, E. and Stirling, I. 2013. Demography and population assessment of polar bears in Western Hudson Bay, Canada. Environment Canada Research Report. 26 November 2013. PDF HERE

Lunn, N.J., Servanty, S., Regehr, E.V., Converse, S.J., Richardson, E. and Stirling, I. 2014. Demography and population assessment of polar bears in Western Hudson Bay, Canada. Environment Canada Research Report. July 2014. PDF HERE [This appears to be the version submitted for publication]

Stapleton S., Atkinson, S., Hedman, D., and Garshelis, D. 2014. Revisiting Western Hudson Bay: using aerial surveys to update polar bear abundance in a sentinel population. Biological Conservation 170:38-47. http://www.sciencedirect.com/science/article/pii/S0006320713004618#

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