Fisheries

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Fisheries

• Question Why do we worry about over-fishing
  the ocean and running out of fish, but not
  over-raising cows and pigs on land and running
  out of them?

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• How are the worlds fish populations doing?

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• How is this effecting total harvest?

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• How about total global fishing?

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• How can this be, given the picture below?

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• Fishing down the food chain
• First they came for the tuna
• Then the salmon
• Then the sharks
• Then the cod
• Then the mackerel
• Then the herring
• Then the anchovies
• ?

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• Fishing new fish, in new places

Fished or mined?
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• What species are most vulnerable?
• High vrs. Low food chain
• Fast breading vrs. Slow

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• Where does this get us?

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• Why does this happen? The Tragedy of the commons

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• Is this rational?

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• So why does it happen?
• Tragedy of Commons
• Political reality

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• This is very hard -- jobs must be lost!
• Fisheries management is an endless argument
  about how many fish there are in the sea until
  all doubt has been removed -- along with all the
  fish. Dr. John Gulland
• Shifting baseline! Is the problem fixed yet?

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• What are laws in America?
• 10 years to maximum sustainable yield
• Ecosystem management
• It can work! But it is hard, and requires
  science.

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• It is not impossible
• But we do not see the ocean as it could be
• Nor do we get from it what we could

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