The landscape of the Strait of Juan de Fuca was carved by ice-age glaciers 13,000 years ago, and their retreat created deep fjords that provide abundant food and habitat for many species of marine mammals. By the mid-1900’s, commercial whaling had pushed many great whales to the edge of extinction, but through decades of conservation efforts, species such as gray whales have rebounded, while others remain endangered and still need help to recover. Along this coastline, local citizens and visitors watch marine mammals throughout the year, including the southern resident orcas that return in spring, as well as passing whales, sea otters, and other animals found from shore. Sea otters, once extinct in Washington waters, were reintroduced when 69 were brought to nearby La Push in 1969, and since then their population has grown to more than 1,000 and their territories have expanded up the strait. The Whale Trail links sites around the region where people may view orcas and other whales or marine mammals from shore.