Karyn Rode is a wildlife biologist for the United States Geological Survey who works in the Chukchi and Beaufort Seas in order to determine the effects of sea ice loss in the Arctic on polar bears. Rode flies helicopters over vast areas of arctic ice, finding bears and tranquilizing them in order to check vitals, collect fat biopsies and blood samples, as well as check if the bears have already been previously tagged. She uses this information to determine population trends and the overall health of bears in the areas. She is also able to ascertain how much time bears spend on land and what kinds of habitats are most conducive to survival. Rode has found that bears in the Beaufort Sea, which is experiencing ongoing sea ice loss, show declining body conditions, declining populations, and lower levels of cub survival. When there is less sea ice, she says, the bears have less access to hunting grounds and seals. Photo credit: Science Friday