With their massive bodies and streamlined forms, gray whales are one of nature's most graceful giants, gliding gently and effortlessly through the water. Every year, they embark on the longest migration of any mammal, 12,000 miles from the icy waters of the Arctic to the warm lagoons of Baja, Mexico, and then back again. In the 1700s and 1800s, gray whales were hunted to near extinction. Thanks to protection from an international treaty and the Endangered Species Act, the eastern Pacific gray whale population has recovered to a sustainable level. Today, a sizeable population of gray whales inhabit the open ocean and continue their impressive annual migration along the coast of North America.