The study noted how adult females and cubs have been particularly affected, and that climate change may be a factor in the decline of a population now estimated at 618, compared to the 842 counted in 2016.
The Arctic is warming faster compared to the rest of the world, and the sea ice on which bears depend for seal hunting is forming later and melting earlier each year, scientists repeatedly report.
They warn that, by 2050, the length of the ice-free season could push these mammals to the brink of starvation.
According to the Canadian government report, these declines are consistent with long-standing predictions of the demographic effects of climate change on polar bears.
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