We know that thick-ice springs occurred in 1974, 1975, 1986, 1992, 2004, and 2005 in the former ‘Eastern Beaufort’ – now the southern portion of the ‘Northern Beaufort’ and the eastern portion of the ‘Southern Beaufort.’ We know that these severe spring ice conditions negatively impacted both polar bears and ringed seals in this region every decade since the 1960s because the effects have been documented by numerous studies conducted in April through May for polar bears (Amstrup et al. 2006; Cherry et al. 2009; Pilfold et al. 2012; Stirling 2002; Stirling and Lunn 1997; Stirling et al. 1980; Stirling et al. 1993; Stirling et al. 2008) and in June and July for ringed seals (Harwood et al. 2012; Smith 1987), see previous posts here, here, and here.
For example, even though Ian Stirling and colleagues argued in their 2008 paper that the thick spring ice conditions in 2004, 2005 and 2006 (but not those in previous decades) were caused by storms initiated or intensified by greater amounts of open water in previous summers, they did not deny that the thick-ice springs occurred. They stated quite clearly that:
“The 1960s, 1970s, and 1980s each experienced a two- to three-year decline in seal productivity in the eastern Beaufort Sea and Amundsen Gulf, associated with heavy ice conditions, around mid-decade. Each was followed by a decline in polar bear reproduction and condition, after which both seal and bear populations recovered (Smith, 1987; Harwood et al., 2000; Stirling, 2002). The beginning of each of those three periods was associated with heavy ice conditions through the winter before the reproductive decline of the seals, followed by a late spring breakup.” [my bold]
So, I have to say, I was shocked but not surprised to find that in the more recent scientific literature, the phenomenon of thick-ice springs every decade in Southern and Northern Beaufort has been deliberately ‘disappeared.’
Not surprised because I suspected it had happened — this issue was a feature of the Stirling and Derocher (2012) paper from late last year which was the topic of my very first blog post, “Cooling the polar bear spin.”
However, I think it is important to document how the transmogrification of sea ice effects on polar bears was managed in the scientific literature so that everyone can see exactly what has been done. In a truly astonishing move for what is supposed to be a field of science, thick-ice springs have been effectively replaced by an open-water red herring as the scourge of Southern Beaufort polar bears.
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![Figure 1. “Movements of 8 satellite-tagged polar bears for the month of September, 2013. Polar bears were tagged in 2013 on the spring-time sea ice of the southern Beaufort Sea. All 8 of these bears have satellite collar transmitters [i.e., all are females]. Polar bear satellite telemetry data are shown with Ice Analysis charts from 26 August, 2013. Ice Analysis charts are made available by the National Ice Center. The land cover is made available by Natural Earth. Click on the above image to enlarge.” [Note that the dots with the polar bear icons are the end points (end September), while the other end of the string is their position in early September, indicating that the ice is now moving towards the shore. The pink dot present in August is almost entirely obscured by the purple dot, on shore in Alaska and the light brown dot is ashore on Banks Island, centre right of the map; two of the bears present in July (see Fig. 2 below) are no longer being tracked - their collars might have stopped working or fallen off (most likely), they might have left the area entirely (also possible) or they might have died. The researchers don’t say.] Click to enlarge](https://i0.wp.com/polarbearscience.com/wp-content/uploads/2013/10/beaufort-tracking-usgs-bear-movements-september-2013.jpg){kind=tracking}
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