Canadian government-funded media outlet CBC ran a story this morning about problem polar bears in the town of Churchill, Manitoba, the self-described “Polar Bear Capital of the World” that contains some very misleading statements from Manitoba Conservation officers. (also see here)
Breakup of sea ice on Hudson Bay was earlier this year than it has been in more than a decade (17 June) and some people are trying to hype the significance of this phenomenon to support a tenuous link to human-caused climate change, even though bears out on the ice this spring were reportedly in good condition and one of the problem bears captured on 8 August was also in good condition (a male weighing 910 lbs, photo above). Unfortunately, reports for similar early breakup years in the early 2000s have not been made public. However, I’ve been keeping track of these Polar Bear Alert Program Reports since 2015 and have read the available literature about their history: these records simply do not corroborate the statements in this CBC account.
From the CBC article (16 August 2023): “Churchill on track for record number of polar bear reports this season, conservation officers say” [my bold]:
As of Aug. 15, Manitoba Conservation officers had responded to 76 calls about polar bears in and around Churchill and were forced to move three of the large carnivores into a holding facility east of the town.
That compares with 18 calls by the same date a year ago.
And officers didn’t have to capture, sedate and house any of those bears in the former military facility — a catch-and-release program that normally does not start until October.
“There are so many polar bears in and around the town of Churchill we are looking at record numbers this year and that’s heavily influenced by where the last ice in the Hudson Bay melts,” said Churchill conservation officer Chantal Maclean, speaking in her office on Tuesday.
History of the Polar Bear Alert Program
The Churchill Polar Bear Alert Program to deal with problem bears has been in place since 1969, although the modern approach that attempts to temporarily incarcerate or fly out of the area the worst problem bears rather than shoot them (or send them to zoos) started in the fall of 1984, after two polar bear attacks (one fatal) occurred in 1983 and another in August 1984 (Kearney 1989; Stirling et al. 1977).
As far as I know, these weekly Alert reports have only been made available online to the public since July 2015 and the earlier reports exist only as hard copies in a file cabinet in Winnipeg. Contrary to the narrative that early breakup of sea ice is correlated with more problem bear reports over the entire season (Stirling and Derocher 2012; Stirling and Parkinson 2006; Towns et al. 2009), 1983 was significant in having one of the latest breakup dates but the highest number of problem bears in the 20th Century.
The Alert program season is not a set period but begins when polar bears appear on the landscape near town and cause problems, so the date of the first report varies widely from year to year. Stirling and colleagues detailed discussion for 1974 and 1975 makes it clear that Alert reports typically began in mid-September during the 1970s, not in October as stated by the CBC article (Stirling et al. 1977:18). In 1983, polar bear specialists noted that the program kicked into gear in late August (Calvert et al. 1986:19 and 24). In the last 8 years, the first reports have varied from late April, due to an anomalous record in 2023 (with the second report not published until mid-June) and late August in 2020.
The number of bears around Churchill every year also varies, and this was true even in the 1970s, when Ian Stirling and colleagues noted that there were a lot fewer bears around in 1973, which could not be entirely explained by the earlier-than-usual freeze-up that saw most bears gone by 8 November (Stirling et al. 1977:17).
Recent Alert Reports
It is important to note that the Alert program seems to have instituted a “zero-tolerance” policy for bears near Churchill after a near-fatal attack on 1 November 2013 in the town itself, which by 2016 increased the number of problem bears reported compared to all previous years.
However, the notion that 76 bear reports by 15 August is an unprecedented number is impossible to confirm, since details for so many years are unavailable. Furthermore, the date itself is not particularly important: rather, the number of weeks that bears have been onshore is a better metric for comparison. This year, 15 August was two days past the 9 week mark: the last report in 2023 was issued 14 August for the week ending 13 August. This means that incidents for two full days were cited by conservation officers that would not have been included in the weekly report, copied below, when the total number of incidents was 70.
You only have to go back to 2021 to find similar numbers of incidents and bears in the holding facility at the end of week 9, see below: some years there were many more than 2023. In addition, having three bears in the holding facility (PBHF) at mid-August is far from the maximum at mid-August: the reports for 2016 and 2018 show that there were five bears in holding those years even though it was only week 5 of each of those seasons!
2023, week 9:
2022 week 9:
Coming at September 19-25, the week 9 report was five weeks later in the season than 2023 because the bears left the ice much later. Note there is no published report for 15 August last year, for unexplained reasons but 18 incidents, as mentioned in the CBC article for last year, seems about right. Unlike 2023, conditions in 2022 were similar to what they had been in the 1980s.
2021, week 9
Week 9 (August 23-29) came two weeks later in the season than this year, but had 69 incidents and saw three bears in holding:
2020, week 9:
In 2020 most bears left the ice so late that the first Alert report came out the last week of August, with only 28 incidents and no bears in holding. However, by week 9 near the end of October there had been 68 incidents and only one bear in holding: 2020 was a very short season, similar to the 1980s.
2018, week 9:
In 2018, week 9 (September 4-9) came four weeks later in the season than 2023 due to bears leaving the ice so much later, but there were a whopping 107 incidents and four bears in holding:
2016, week 5:
In 2016, the second week in August was week 5, but there had already been 56 incidents and 5 bears in holding; by week 9, there were many more (see next entry).
2016, week 9:
In 2016, by the time week 9 rolled around in September, there had been 107 incidents and 11 bears were in holding:
Calvert, W., Stirling, I., Schweinsburg, R.E., et al. 1986. Polar bear management in Canada 1982-84. In: Polar Bears: Proceedings of the 9th meeting of the Polar Bear Specialists Group IUCN/SSC, 9-11 August, 1985, Edmonton, Canada. Anonymous (eds). Gland, Switzerland and Cambridge UK, IUCN. pg. 19-34.
Kearney, S.R., 1989. The Polar Bear Alert Program at Churchill,Manitoba. In: Bromely, M. (Ed.), Bear–People Conflict: Proceedings of a Symposium on Management Strategies, Yellowknife, Northwest Territories Department of Renewable Resources, pp. 83–92. [courtesy M. Dyck, Gov’t of Nunavut] Pdf here.
Stirling, I. and Derocher, A.E. 2012. Effects of climate warming on polar bears: a review of the evidence. Global Change Biology 18(9):2694-2706. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2486.2012.02753.x/abstract [paywalled]
Stirling, I., Jonkel, C., Smith. P., et al. 1977. The ecology of the polar bear (Ursus maritimus) along the western coast of Hudson Bay. Canadian Wildlife Service Occasional Paper No. 33. pdf here.
Stirling, I. and Parkinson, C.L. 2006. Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic. Arctic 59:261-275. http://arctic.synergiesprairies.ca/arctic/index.php/arctic/issue/view/16.
Towns, L., Derocher, A.E., Stirling, I., Lunn, N.J. and Hedman, D. 2009. Spatial and temporal patterns of problem polar bears in Churchill, Manitoba. Polar Biology 32(10):1529-1537. http://link.springer.com/article/10.1007%2Fs00300-009-0653-y