As the Arctic sea ice continues to shrink, scientists at the U.S. Geological Survey report that more and more polar bears are giving birth on land.
Between 1985 and 1994, 62 percent of female bears dug their snow dens in the sea ice. That number fell to just 37% between 1998 and 2004.
According to the lead author of the study, "the sea ice changes may have reduced the availability or degraded the quality of offshore denning habits.
