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8 Cards in this Set
- Front
- Back
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fishery stats
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-16% of protein consumed by humans comes from fisheries
-30% of global fish stocks are depleted or overfished; 47% at limit -in US 80% of 191 commercial stocks are fully or overexploited -90% of large fish been removed -predators shrinking in size --we concentrate on high trophic levels--insufficient way to obtain biomass |
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why decline?
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-too good at catching
-don't understand enough abt population dynamics -management of industry -tragedy of the commons -non-human impact, pollution -bycatch |
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standing stock
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mass present in an ecosystem at a given time
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overfishing
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occurs when harvesting takes place so rapidly that the majority of hte population is sexually immature
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maximum sustainable yield
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maximum fishery biomass that can be removed yearly and still be sustained by the fishey ecosystem
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bycatch
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incidental catch
-1/4 of catch discarded -shrimp fisheries=bycatch 8 times larger -18-36 million metric tons/yr |
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fisheries management
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-regulate to maintain sustainable fishery
-assess ecosystem health, determine fish stocks, analyze fishing practices, set adn enforce catch limits -problem: migration,etc -usually more concerned w/ maintaining jobs |
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ecosystem services
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-concept of those products or functions an ecosystem provides for a human demand
-place value on to make decisions--like how much it would cost to replace an estuary filled with waste |
