There is irrefutable evidence from Barents and Chukchi Sea subpopulations, among others, that polar bears are fat and reproducing well despite marked declines in summer sea ice over the last two decades. These indicators of physical and reproductive health, in any species, are signs of thriving populations. However, these facts negate the premise that polar bears require abundant summer sea ice to flourish, and that creates a problem for polar bear specialists who continue to make that claim (Amstrup et al. 2007; Crockford 2017, 2019).
In other words, the assessment that polar bears are currently thriving is not based solely on estimates of a slight increase in global population size but on published data gathered from field studies on the bears’ physical and reproductive health.
Oddly, biologists repeatedly turn to data from Western Hudson Bay to drive home to the public their preferred message that polar bear health and abundance are being negatively affected by recent summer sea ice declines. However, they fail to mention that robust field data from many other regions, including the Barents and Chukchi Seas, support the opposite conclusion. Moreover, wherever possible, they mumble under their breath (or leave out entirely) the fact that poor ice conditions could not be blamed for a 27% decline in polar bear numbers in Western Hudson Bay since 2016 — because their own data showed sea ice conditions had been strong!Continue reading