Puget Sound Regional Council major cities are Seattle, Bellevue in King County, Tacoma in Pierce County, Everett in Snohomish County, and Bremerton in Kitsap County. The region's population was estimated to be over 3.8 million as of April 2014. In 1956 the four counties of the Puget Sound region established the Puget Sound Regional Planning Conference, which changed its name to the Puget Sound Governmental Conference (PSGC) in 1958. It launched the Puget Sound Regional Transportation Study (PSRTS) in 1962 with support from the Washington State Highway Commission, the U.S. Bureau of Public Roads (predecessor of the Federal Highway Administration), and the U.S. Department
Puget Sound sea urchins, and sand dollars. Dungeness crabs ("Metacarcinus magister") occur throughout Washington waters, including Puget Sound. Many bivalves occur in Puget Sound, such as Pacific oysters ("Crassostrea gigas") and geoduck clams ("Panopea generosa"). The Olympia oyster ("Ostreola conchaphila"), once common in Puget Sound, was depleted by human activities during the 20th century. There are ongoing efforts to restore Olympia oysters in Puget Sound. There are many seabird species of Puget Sound. Among these are grebes such as the western grebe ("Aechmophorus occidentalis"); loons such as the common loon ("Gavia immer"); auks such as the pigeon guillemot ("Cepphus columba"), rhinoceros auklet