What is the Salish Sea?

The Salish Sea is the combined intricate inland sea between Vancouver Island and the British Columbia and Washington mainland. The name was officially recognised by the United States Board on Geographic Names in 2009 and the British Columbia Geographical Names Office in 2010, honouring the Coast Salish peoples who have lived around the sea for thousands of years. The Salish Sea includes three previously named bodies of water: the Strait of Georgia (between Vancouver Island and the BC mainland), the Strait of Juan de Fuca (between Vancouver Island and Washington's Olympic Peninsula), and Puget Sound (in Washington State).

The Strait of Georgia is the largest part of the Salish Sea and the only Canadian section beyond a small portion of the Strait of Juan de Fuca. It runs about 240 kilometres from the Discovery Islands in the north to the United States border at Boundary Pass, with widths of 18 to 55 kilometres. The Strait of Juan de Fuca runs about 154 kilometres from Cape Flattery, Washington east to Race Rocks, BC, marking the international maritime boundary. The Strait was named for explorer Juan de Fuca (Apostolos Valerianos), a Greek navigator who claimed to have discovered the strait while sailing for Spain in 1592 (though his claim is disputed).

The Salish Sea is a major shipping waterway. The Strait of Georgia is the principal access to the Port of Vancouver (the largest port in Canada), the Strait of Juan de Fuca leads to the Port of Seattle and Tacoma in the United States, and the BC Ferries system operates the world's longest fleet of car ferries across the Strait of Georgia. About 11,000 commercial ship transits and 47 million ferry passengers cross the Salish Sea annually. The Salish Sea hosts important populations of southern resident killer whales (a critically endangered ecotype, with about 73 individuals), transient killer whales, harbour and Dall's porpoise, harbour seals, Steller sea lions, salmon, and Pacific halibut.

The Salish Sea bioregion is shared by 19 Coast Salish First Nations and tribes including the Cowichan Tribes, Tsawwassen, Tsleil-Waututh, Squamish, Musqueam, Tla'amin, Lummi, Suquamish, and Tulalip. The 2014 Coast Salish Gathering and subsequent transboundary meetings have addressed shared ecosystem management. The Salish Sea Marine Survival Project (2014 to 2019) was a major Canada-US scientific collaboration on declining salmon and marine survival. The 2018 federal Trans Mountain Pipeline expansion approval (with the federal government purchasing the pipeline in May 2018 for $4.5 billion) generated significant concern about increased oil-tanker traffic through the Salish Sea and was central to subsequent litigation including Tsleil-Waututh Nation v. Canada (2018).