SAB: Coastal Programs

BCMEC Ecosections

Physiographic Features: Narrow constricted channels
Oceanographic Features: Protected coastal waters with strong currents; well-mixed, poorly stratified
Biological Features: Migratory corridor for anadromous fish; rich sessile, hard substrate invertebrate community; diverse species assemblage of benthic fish
Boundary Rationale: Johnstone Strait has greater mixing and more channels that areas to south; Queen Charlotte Strait more marine

Physiographic Features: Steep sloping shelf
Oceanographic Features: Strong across slope and downslope turbidity currents
Biological Features: Upwelling zone; productive coastal plankton communities and unique assemblages of benthic species
Boundary Rationale: Transitional area between continental slope and abyssal plane

Physiographic Features: Across-shelf trough with depths mostly <300m; surrounded by low-lying coastal plains (Hecate Depression)
Oceanographic Features: Strong freshwater influence from mainland river runoff drives northwestward flowing coastal buoyancy current and estuarine-like circulation
Biological Features: Mixture of neritic and subpolar plankton species; migratory corridor for Pacific Salmon; some productive and protected areas for juvenile fish and invertebrate development
Boundary Rationale: Distinguished from are to south by strong freshwater discharge influence

Physiographic Features: Broad shallow basin surrounded by coastal lowlands (Georgia Depression)
Oceanographic Features: Protected coastal waters with significant freshwater input, high turbidity and seasonal stratified; very warm in summer
Biological Features: Nursery area for salmon, herring; abundant shellfish habitat; neritic plankton community
Boundary Rationale: Stronger Fraser River signature that areas to north or west

Physiographic Features: Deep trough; major structural feature accentuated by glacial scour
Oceanographic Features: Semi-protected coastal waters with strong "estuarine-like" outflow current (coast hugging buoyancy current to north); major water exchange conduit with "inland sea"
Biological Features: Migratory corridor for anadromous fish; moderately productive; mixture of neritic and oceanic plankton species
Boundary Rationale: Much more marine than Strait of Georgia; less "open shelf" that Vancouver Island Shelf

Physiographic Features: Predominantly shallow <200m, high relief area with deeper fjord areas
Oceanographic Features: High current and high relief area; very well mixed; moderate to high salinities with some freshwater inputs in the inlets and fjords
Biological Features: Very important for marine mammals; migratory corridor for anadromous fish; moderate shellfish habitat
Boundary Rationale: More marine than Johnstone Strait; much more shallow with high relief and high currents that Queen Charlotte Sound

Physiographic Features: Deep, narrow fjords cutting into high coastal relief
Oceanographic Features: Very protected waters with restricted circulation and often strongly stratified
Biological Features: Lowe species diversity and productivity due to poor water exchange and nutrient depletion; unique species assemblages in benthic and plankton communities
Boundary Rationale: Unique physiography and stratification compared to bordering surrounding regions

Physiographic Features: Very shallow strait dominated by coarse bottom sediments; surrounding coastal lowlands
Oceanographic Features: Semi-protected waters with strong tidal currents promote mixing; dominantly "marine" waters

Physiographic Features: Includes abyssal plain and continental rise; a major transform fault occurs along the west margin and a seamount chain trends NW/SE
Oceanographic Features: The eastward flowing subarctic current bifurcates at coast with northerly flowing Alaska Current; current flow is generally northward throughout the year

Physiographic Features: Wide, deep shelf characterized by several large banks and inter-bank channels
Oceanographic Features: Ocean wave exposures with depths mostly > 200m and dominated by oceanic water intrusions

Physiographic Features: Includes abyssal plain, and continental rise; also includes spreading ridges, transform faults, triple junction and plate subduction zone
Oceanographic Features: Area of variable currents; southerly areas may be affected by southward flowing California Current in summer but remainder of area characterized by weak and variable currents; Davidson Current along shelf edge flow north in winter, south in summer

Physiographic Features: Narrow, gently sloping shelf
Oceanographic Features: Open coast with oceanic wave exposures; northward, coast hugging buoyancy current due to freshwater influence; seasonal upwelling at out margin
Biological Features: Highly productive with neritic plankton community; northern limit for hake, sardine, northern anchovy, and Pacific mackerel; productive benthic community; rich fishing grounds for benthic fish and invertebrates
Boundary Rationale: More open shelf than Juan de Fuca Strait; more freshwater influence (coastal buoyancy current) that Queen Charlotte Sound

For more detailed information on the Marine Ecosections of British Columbia please see the following publication:

British Columbia Marine Ecological Classification: Marine Ecosections and Ecounits January 1997 http://www.ilmb.gov.bc.ca/risc/pubs/coastal/marine/index.htm.