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Oceans
http://life.uiuc.edu/animalbiology/105/http://life.uiuc.edu/animalbiology/105/ID: eee105ID: eee105Password: prAIRiePassword: prAIRie
Who owns the Oceans?
3 miles off coast3 miles off coast or 12 miles?or 12 miles? or continental margin?or continental margin?
Territorial watersTerritorial waters
Continental shelfContinental shelf
Who owns the Oceans?
3 miles off coast3 miles off coast or 12 miles?or 12 miles? or continental margin?or continental margin?
Territorial watersTerritorial waters
Continental shelfContinental shelf200 mile fishing control 200 mile fishing control
Who owns the Oceans?
Tragedy of the Commons
Garrett Hardin, Science, 162(1968):1243-1248.
Tragedy of the Commons
• Freedom in a commons brings ruin to all.
Garrett Hardin, Science, 162(1968):1243-1248.
Fishing13% of world’s protein from the oceans13% of world’s protein from the oceans
Overfishing
Atlantic codAtlantic cod
Overfishing
Canadian Cod CatchCanadian Cod Catch
Overfishing1994 U.S.Commerce Dept.1994 U.S.Commerce Dept.
closed Georges Bank to fishing.closed Georges Bank to fishing.
Cod are “commercially extinct”Cod are “commercially extinct”
Overfishing
• ‘‘60’s-’70’s Alaskan salmon declined60’s-’70’s Alaskan salmon declined
• ‘‘70’s Peruvian anchovy collapsed70’s Peruvian anchovy collapsed
• ‘‘90’s Newfoundland cod closed90’s Newfoundland cod closed
• ‘‘98 North Atlantic salmon moratorium98 North Atlantic salmon moratorium
• 80% of U.S.’s 191 commercially80% of U.S.’s 191 commercially
important fish stocks are fullyimportant fish stocks are fullyexploited or overfishedexploited or overfished
Overfishing
American Fisheries SocietyAmerican Fisheries Society
November 2000 reportNovember 2000 report
lists 82 marine fish species lists 82 marine fish species endangeredendangered
OverfishingAs coastal fisheries become barren, As coastal fisheries become barren, fishers turn to deeper waters. fishers turn to deeper waters.
e.g. discovery of Orange Roughy, 1980’s e.g. discovery of Orange Roughy, 1980’s
live to 150 years live to 150 years don’t breed until 30 don’t breed until 30
OverfishingAs coastal fisheries become barren, As coastal fisheries become barren, fishers turn to deeper waters. fishers turn to deeper waters.
e.g. discovery of Orange Roughy, 1980’s e.g. discovery of Orange Roughy, 1980’s
Overfishing
Overfishing
Drift Netting
• 40 - 90 mile gill nets
international waters in 1992Banned by United nations from
“Wall of Death”
Drift Netting
Dolphin-free Tuna
In Eastern Tropical Pacific yellowfin tuna
accompanied by dolphin schools
Dolphin-free Tuna
Tuna were captured by encirclement
Dolphins died in great numbers
Dolphin-free Tuna
by encirclementby encirclementU.S. Congress banned tuna caughtU.S. Congress banned tuna caught
Banned foreign-caught tuna if encircled Banned foreign-caught tuna if encircled
Created Dolphin-Free Label Created Dolphin-Free Label
Tuna canners & stores volunteered Tuna canners & stores volunteered
Dolphin mortality declined Dolphin mortality declined
Dolphin-free Tuna
However U.S.Government now backtracking However U.S.Government now backtracking
Whaling
Whaling
Whaling
Minke Whales
SpermWhalesSpermWhales
Minamata
‘‘50’s periodic fish kills50’s periodic fish kills
““cat suicides”cat suicides”
““cat dancing disease”cat dancing disease”
Minamata disease
bacteriabacteria
Minamata disease
metallic mercurymetallic mercury
Methyl mercuryMethyl mercury
Absorbed into fatsAbsorbed into fats
Gray mulletGray mullet 10.6 ppm Hg10.6 ppm Hg
crabcrab 35.7 ppm Hg35.7 ppm Hg
HumanHuman liverliver 70.5 ppm Hg70.5 ppm Hg
kidneykidney 144 ppm Hg144 ppm Hg
BioaccumulationBioaccumulation
Minamata disease
Jan. 12, 2001 -- Pregnant women should avoideating certain species of large ocean fish, theFDA announced today, because of a danger of
contamination by methyl mercury, a substance
that can harm the nervous system in a
developing baby.