U.S. protections for the waters that a group of endangered orcas call home could soon expand beyond the Seattle area to encompass much of the West Coast, from the Canadian border to central California. The National Oceanic and Atmospheric Administration issued a proposal Wednesday to increase the critical habitat designation for southern resident killer whales by more than sevenfold under the Endangered Species Act. Just 73 orcas remain in the Pacific Northwest population, the lowest number in more than three decades. They're struggling with a lack of chinook salmon, their preferred prey, as well as toxic contamination and vessel noise.