abiotic effects of overfishing:
•    geological factors: sediment
•    chemical: pH, water quality, water temperature, weather/climate
biotic effects of overfishing:
•    damage to sea floor - may take years to repopulate
•    population shift for food chain
georges bank -
•    three areas totaling 17000 km^2 closed to groundfishing
•    fishing mortality of groundfsh & scallops reduced
•    haddock, yellowtail, witch flounder populations increasing
•    many species still well below historic levels of biomass
•    reserves can be effective for industrial fisheries in temperate continental shelf settings
effects of closed areas:
•    short term: unemployment, reduced income, overwhelming debt, increase in fish prices
•    long term: minimum of twenty years before fish reach fishable level; fleets will have to be rebuilt at higher cost; debts from rebuilding fleets encourage overfishing; lost tradition effects cultural identity
•    large-scale effects on commercial/recreational fishermen
    o    benefits: increase in catch (outside area), reduction in variation catch, better catch mix (more older fish)
    o    costs: decrease in catch (within area), congestion of fishing grounds, user conflicts, high costs w/ fishing location, increase in safety risks
•    effects on divers, eco-tourists, etc.
    o    benefits: maintain species diversity, greater habitat complexity and diversity, higher density levels
    o    costs: damage to marine ecosystem, loss of traditional fishing community
government response?
•    Subsidize fishermen -> most fishermen still below poverty line
•    Fishermen go through job training (paid by taxes)   
    o    Additional labor drives down wages
Conclusion:
•    Closed areas have variable, and generally poor effects on humans in the short term
•    Both fish and humans benefit in the long term
•    Need more measures than just closed areas to maximize benefits

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