Canada’s Marine Canada’s Marine EnvironmentsEnvironments

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