Fisheries issues of the world ocean

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Fisheries issues of the world ocean

• Figures, Facts and Factors

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Coastal Facts

• Coastal area 20 of land area, but 39 of world
  population lives within 100 km of it
• 19 of land within 100 km of coastal areas is
  altered to urban or agricultural use
• 57 of continental shelf of fishing nations is
  trawled (8.8 million km2)
• Relatively small spatial units, often submerged,
  difficult to assess with coarse-scale global
  sensors

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Whats happening in fish habitat?
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Chemical contaminant issues
http//www.us-ecosystems.org/coasts_oceans/synthet
ic_organics/
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Global climate change issues

• Severe storm events
• Increased agricultural runoff
• Accelerated eutrophication
• Changing thermal niches
• Loss of coastal wetlands for spawning
• Expanded ranges of non-native organisms

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Overfishing

• Ecological extinction caused by overfishing
  precedes all other pervasive human disturbance to
  coastal ecosystems, including pollution,
  degradation of water quality, and anthropogenic
  climate change (J.B.C. Jackson, et al, 2001.
  Historical overfishing and the collapse of
  coastal ecosystems. Science 293, 5530. 629-637.)

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Historical sequence of human disturbances
affecting coastal ecosystems
Jackson, et al, 2001
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Whats happening in fishing?
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Food web changes before and after overfishing the
historical ecosystems Jackson et al, 2001
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A Fishery Story The Downeaster Alexa

• Song by Billy Joel, 1989
• Changes in striped bass commercial fishery
• Investigation of contributing factors
• Overfishing
• Global climate change
• Predators, other biotic interactions
• Water quality
• Disease