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Download Canada`s Marine Environments
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Canada’s Marine Environments The Arctic Ocean • Coldest ocean area • ~173 000 km of coastline • Seasonally covered in ice • Key Polynyas in the region • These are biological hotspots, unfrozen sea ice • Subsistence hunting and fishing are the major human uses in the region • Only a small arctic char commercial fishery • It was probably fished at or above the maximum sustainable yield • Large marine mammals dominate the region • Some subsistence hunting of whales, even the endangered Bowhead whale • Bioaccumulations and biomagnifications are large problems with marine life in the arctic • Hydroelectric dams on rivers flowing into the arctic region are having serious affects on anadromous fish species • Climate change is the largest and most serious threat to the Arctic marine environment • Will/is having dramatic affect on sea ice cover • Oil/gas exploration as well as diamond mines are also threatening the area Pacific Ocean • Smallest coastline • Warmest waters • Mixing of north and south currents creates a highly productive region • Major fish species include: 5 species of salmon, 3 species of trout • Cod, flounder, lingcod, herring, shrimp, crabs, scallops, clams are all important commercial fish • Commercial fishing in BC employed 5400 people (declining) made ~ $358 million • Recreational fishing in BC employed 8900 people and made ~ $675 million • Today the BC salmon fishery is collapsing - see articles posted on website Threats include: • Rising ocean temps • El nino • Wastewater is the worst offender • Urban and agricultural runoff • Oil • Chemical spills Atlantic Ocean • Used to be world’s richest ground for Cod • Said to be so thick they would slow ships • 1992 moratorium on cod • Stocks declined 97% in 30 years • Cod is now and endangered species • Coastline is about 40 000 km • Large continental shelf • High levels of biological activity because of the meeting of warm Gulf Stream and cold Labrador Current • Upwelling occurs here… lots of nutrients • Nova Scotia current also plays a role Threats • Lack of knowledge • Marine pollution • Municipal and industrial effluent • Heavy metals • Improper total allowable catches • • • • • Pulp and paper mills Mines Food processing plants Agricultural runoff Discarded fishing nets (ghostfishing) • bycatch
