West Coast of Vancouver Island OVERVIEWThe West Coast of Vancouver (WCVI) is a unique and rich marine ecosystem that is valuable to residents, Canadians, and the international community. It provides food, energy, money, water, culture, tourism, recreation, commercial fisheries, transportation routes, and knowledge.
The WCVI area stretches along approximately 300 kilometers (as the eagle flies) from Brooks Peninsula Northwest of Kyuquot Sound to Southeast of Sheringham Point including Port Renfrew. The WCVI marine area extends from the high water mark in intertidal and estuarine zones offshore to the 200 nautical mile limit of the Exclusive Economic Zone (EEZ) or the international boundary in the Juan de Fuca Strait.
WCA’s geographic scope reflects the ‘Ha-houlthee’ (territorial wealth) of fifteen Nuu-chah-nulth Nations. It is divided into several regional districts including Alberni-Clayoquot, which has 30,664 residents across a 6,597km2 area. The Cowichan Valley Regional District, Capital Regional District and Strathcona-Comox Regional District also have governance boundaries that include portions of the area.
Nuu-chah-nulth people have survived and thrived along the WCVI coastline for millennia, supported by rich and diverse coastal and ocean ecosystems. These include rain forests, extensive systems of rivers and lakes, a coastline of glacially-carved fjords and inlets that function as estuaries with important and distinct hydrological and oceanographic characteristics, a coastal ocean that is among the most productive in the world, and a beauty and meaning that transcends any accounting of its parts.
It has been estimated that the WCVI area contributes an estimated economic value in excess of $650 million Canadian dollars (CDN) annually from diverse ocean activities. For example, it is one of the largest convergence zones for marine shipping and navigation in the world. About CDN$90 million of trade goods pass under the Lions Gate Bridge in Vancouver every day—most of these come through the WCVI marine area. At the same time, given its relatively pristine state, tourism is a significant economic activity with over a million visits per year from all over the world.
The WCVI is one of North America’s most important recreational and commercial fishing grounds, second only to Georges Bank with the highest commercial volume of fish harvested in North America. There are a number of finfish, shellfish, and marine plant aquaculture operations in the area, producing over 20% of BC’s total aquaculture volume. There is potential for alternative energy sources (wind, hydro, tidal) as well as oil, gas, and frozen methane exploration and development. There is also mining potential (including seabed minerals) and forestry use. The area has the highest rainfall in Canada and a large diversity of types and forms of water. Oceans science, technology, and research are also key activities bolstered by institutions such as the Bamfield Marine Sciences Centre and Project NEPTUNE.
Biophysical OverviewAt >49°N latitude, the WCVI region marine management area incorporates most of one of the three Marine Ecoregions in British Columbia - a sea extending West of Vancouver Island to the 200 nautical mile Exclusive Economic Zone. It includes portions of four of the 12 Ecosections within the British Columbia Marine Ecological Classification -- Vancouver Island Shelf, the Continental Slope, the Juan de Fuca Strait, and the Transitional Pacific.
Geologically, the region is formed by dynamic and powerful processes. The Juan de Fuca Plate is being pushed and is sliding underneath the North American Plate. This subduction process has helped form the Vancouver Island and Olympic Peninsula mountain ranges. The coastal landscape has also been fundamentally influenced and shaped by the advance and retreat of various ice sheets. The most recent of these was the Cordilleran Ice Sheet, which retreated by 15,000 years ago.
The characteristic coastal fjords and headlands are surrounded by mountains covered by coastal temperate rainforest. All of the fjords are estuarine to some degree meaning that freshwater flows into a marine salt water area and are therefore influenced by stream flows that peak during the winter due to heavy rainstorm events. These estuarine environments are highly productive ecosystems due in part to the nutrients that flow from rivers; they are also highly dynamic and as a result the region has a high level of marine biodiversity compared to other marine and coastal areas at similar latitudes around the world.
The region’s mild climate is moderated by the effects of the North Pacific Ocean, which includes atmospheric heating during winter, cooling during summer, and considerable rainfall from the saturated Pacific air. Temperatures range from 0 °C in January to between 28–33 °C during summer months. Henderson Lake is the wettest place in North America with average annual precipitation ranges of about 6,650 millimetres. Precipitation is heaviest in the autumn and winter. Snow is rare at low altitudes but is common on mountaintops in winter.
Sea level is influenced by many factors including global ice budgets, thermal expansion of seawater, and crustal loading, subsidence, and rebound; sea level is now rising due to climate change effects. In addition, the WCVI and the adjoining Vancouver Island Shelf are fully exposed to the waves of the North Pacific Ocean. This affects both the geomorphology and the coastal and marine biota. The continental slope along the West Coast is characterized by strong turbidity currents flowing across and down the slope.
Summer upwelling of nutrient-rich water from the adjacent deep sea enhances the productivity of the area. As such the marine areas of the WCVI has more than 10,000 known species, including an estimated:
- 371 species of fish
- 37 species of marine mammals
- 50,000 species of bacteria
- over 6500 invertebrate species (236 crustacean species, 3694 gastropod species, and 191 mollusc species)
- between 530 to 979 macroalgae species
- one of the highest kelp diversities in the world
- 481 observed zooplankton species
- Between 371 to 409 marine fish species, with 25 species known to occur in both fresh and saltwater
- 30% (37) of the world’s 125 marine mammal species including killer whales, grey whales, and humpback whales, and,
- a rich diversity of seabirds including albatrosses, petrels, fulmars, shearwaters, storm-petrels, phalaropes, skuas, gulls, terns, murres, guillemots, murrelets, auklets, and puffins.
Several other factors explain the relatively high species diversity. These include high habitat diversity at different scales, high spatial and temporal variability of regional and local oceanography, the overlap of northern and southern species ranges associated with the coastal oceanographic transition-zone of the transitional Pacific, and the high productivity of coastal and ocean waters.
Over millennia, profound ecological changes have defined the natural and cultural histories of the region. Its biota began arriving, developing, and departing long before geological processes had finished forming the modern landscape, which occurred about two million years ago. The arrival and fluctuations of human populations within the last 10,000 years has strongly influenced and shaped the ecology of the area by reducing the biomass and abundance of species that were hunted and gathered.
When Europeans arrived in the 18th century human activities and exploitation of the area has undergone various phases, some of which having large impacts. Most extractive activities have undergone boom and bust cycles, and in general human stressors have increased and despite the general productivity of British Columbia’s coastal oceans, populations of many species have been declining with increased human presence and activity.
WCVI salmon stocks are keystone species that indicate change in marine and terrestrial environments. They have undergone declines in abundance and/or size in many parts of the region. A further fourteen of the 37 mammal species are at risk of extinction. There are also numerous birds, other fish and plant species at risk or threatened. The reasons for these declines are complex and differ among species and stocks, but increasing pressures of various kinds, including both local and global changes, need to be addressed in order to reverse trends.