Environment Counts | Polar bears losing weight as sea ice extent declines :

Sea ice is declining over much of the Arctic. In Hudson Bay the ice melts completely each summer and earlier break-ups are resulting in longer ice-free seasons. A new study examined ice trends trends for 1980–2012 in Southern Hudson Bay.

The researchers compiled break-up and freeze-up dates within the entire region and within smaller coastal break-up and freeze-up zones. They examined trends in body condition for 900 bears captured during 1984–1986, 2000–2005, and 2007–2009. The analysis showed that the ice-free season increased by about 30 days from 1980 to 2012. It was found that the body condition of polar bears decreased significantly for all social classes between the 1980s and 2000s representing a loss in body mass of approximately 45 kg for males and 31 kg for females, or about 10%. M.E. Obbard et al., Arctic Science, 2016, 2(1): 15-32, 10.1139/as-2015-0027