The Strait of Georgia is 220 km (135 miles) long and from 25 to 55 km wide (15 to 35 miles). Some people call it the "Gulf of Georgia", as that was the name Captain Vancouver first gave it - and the reason why the hundreds of islands here are called the Gulf Islands.
150 million years ago colliding continental plates created the Georgia Depression. Within the Depression are the Strait of Georgia and Puget Sound, together known as the Georgia Basin.
14,000 years ago, a slow moving river of ice flowed through the Fraser Valley and formed the Strait of Juan de Fuca, the body of water that separates Vancouver Island from the Olympic Peninsula in Washington State.
While advancing south and west, the enormous glaciers carved hills and valleys and their slow meltdown and retreat made room for the temperate climate which characterizes the Georgia Basin today. The Coast Salish people have lived here since the glaciers retreated. They called the region "Sqla-lot-sis" [phonetic pronunciation], which means "homeland".
A 1970 study by Canada's federal parks branch called Georgia Strait "one of the world's most spectacularly beautiful and ecologically rich areas" close to a population concentration. Today, Parks Canada says that southern Georgia Strait "the most at-risk natural environment in Canada".
The Strait is fed by freshwater from the huge Fraser River system, which carries rich silt and fresh water far across the Strait. This 850-mile long river drains over 20 million hectares - one quarter of BC. It has the largest salmon runs in North America and its estuary is a vital stopover spot for migrating birds from three continents. Aside from the mild climate, one of the main reasons that the Strait of Georgia is so rich in wildlife is because of the Fraser River and the fresh water, silt and nutrients it carries far into the Strait.
These waters support an estimated 3000 species of plant and animal life. These include:
about a dozen species of marine mammals, including seals, porpoises, dolphins, killer whales and sea lions
almost 200 species of fish
over 100 species of marine birds
500 marine plant species, including about 200 varieties of different seaweeds more than 1500 invertebrates.
The Strait has a wide variety of habitats. You can find pristine sandy beaches, rocky shores, steep cliffs, sandstone shelves, mudflats, and deep fjords - all these and more.
But from a biological point of view, the most productive habitats in the region are estuaries - the places where rivers meet the sea, and fresh water gradually mixes with salt. Estuaries make up less than 3% of BC's coastline - yet they are essential, at some point of the life cycle, to 80% of the wildlife.
For example, salmon must spend time in the estuary as young smolts, getting used to salt water, before they head to the ocean - and they're dependent on estuaries again when they return as adults to spawn. In winter, when ponds ice over and fields vanish under snow, waterfowl and migrating birds depend on estuaries, where they can still get food and water. Intertidal areas and estuaries are also important food sources for larger animals such as bear, deer, river otters, mink and muskrat.
The Fraser River estuary is a vital point on the bird migration route known as the Pacific Flyway. It provides a rest and stopover between California and Alaska and a wintering ground for at least 100,000 waterfowl. At the peak of migration, up to 180,000 ducks and geese fly into the Fraser delta in a single day. The Fraser estuary and Boundary Bay together form the largest winter waterfowl resting area on the west coast of North America.
There are many other important estuaries in the Strait of Georgia. As well as being vital for fish and wildlife, salt marshes and other wetland vegetation serve as the "kidneys" of the ecosystem, trapping and holding water and air-borne contaminants such as the sulfur in acid rain.
Georgia Strait is important not only in a biological sense, but is essential to the human population of the region for income, transportation, recreation and spiritual sustenance. These waters have been important for commercial, sports and aboriginal fishing. The shellfish industry is also economically important, with many shellfish growers located in communities around the Strait. Many others work on these waters in transport, towing and other forms of marine commerce. Tourism is the fastest-growing industry and now probably the most important one to the region.
The Strait and its watersheds face serious environmental problems - the bulk of these caused by region's rapid human population growth and the urbanization and development that has come with it. The human population around the Strait is expected to increase from its current level of 2.9 million to 3.6 million by the year 2010. (If the population of adjacent Puget Sound is factored in, these figures rise to nearly 6 million today and nearly 10 million by 2010.). Toxic chemicals and sewage outfalls are only two of many threats to marine life that come from this growing human population.
