National Geographic : 2018 Jun
A polar bear and her cubs explore a spit of land projecting into the Beaufort Sea, waiting for the water to freeze enough so they can hunt seals—their main food source. The loss of sea ice caused by a rapidly warming cli- mate has forced polar bears to scrounge for scraps onshore and has reduced the southern Beaufort population by 40 percent. NEXT PHOTO Like feathered fighter jets, snow geese make a few last passes over the tundra in autumn before heading south to California and Mex- ico. More than 200 species of migratory birds spend summers in the refuge, creating a living connection between it and every continent but Australia.