Sea otter in Bartlett Cove, Glacier Bay National Park and Preserve, Alaska

Sea otter, Glacier Bay, Alaska

It's hard not to smile when you spot a sea otter. Their whiskery faces, busy paws and thick fur give the impression of a stuffed animal that has come to life and taken to the ocean. These heaviest members of the weasel family aren't just cute though, they also play a vital role in the kelp forest ecosystem, keeping the destructive sea urchin population in check. Unfortunately, their populations, which once numbered as high as 300,000, dropped to fewer than 2,000 after widespread hunting. International protections were put into place in 1911 and numbers have rebounded to around 125,000, but they still remain endangered. While some habitats never recovered, others have emerged in entirely new locations, such as Glacier Bay National Park and Preserve. In 1995, five sea otters were spotted in Glacier Bay, and today there are over 8,000 that hunt, play and raise pups in the kelp-abundant waters.