2011 10.5 overfishing

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  • 1.  
  • 2.
    • Catching too much fish for the system to support by reproduction.
    • A non-sustainable use of the oceans leading to extinction of certain species.
    • On a global scale we have enough fishing capacity to cover at least four Earth like planets.
    • Many fishing methods are so harmful that they are unsustainable in their own way.
  • 3.
    • If overfishing continues, fish populations will be reduced even more, no matter what measures are taken.
    • Overfishing not only depletes the fish but seriously harms marine environment.
    • Because the fish population has decreased so much, many other species have been placed at risk because they now lack their major food source.
  • 4.
    • Fish Stocks (1):
    • 52% of fish stocks are fully exploited
    • 20% are moderately exploited
    • 17% are overexploited
    • 7% are depleted
    • 1% is recovering from depletion
    • Between 1950 and 1994, the ocean fishing industry increased the total catch by 400%. (3)
    • Global Fish Stocks are expected to Collapse by 2050 at Current Exploitation Rates. (3)
  • 5.
    • Between 1950 and 1994, the fishing industry increased the total catch by 400%. (3)
    • Global Fish Stocks are expected to collapse by 2050 at current exploitation rates. (3)
    • Fish Stocks (1):
    • 20% are moderately exploited
    • 52% are fully exploited
    • 28 % are overfished, depleted, or recovering
  • 6. The graph points out that current levels of fishing are obviously unsustainable.
  • 7. These 10 ecosystems were studied for their MMSY, or multi-species maximum sustainable yield. Fishing below MMSY provides ecosystems with a chance to recover.
  • 8.
    • Huge negative effects on the global economy and spawns malnutrition.
    • Global fisheries provide about $225 - $240 billion each year.
    • If more sustainable practices were used, there would be a $36 billion addition to that yearly profit – 16% increase in global income.
    • Between 1950 and 2004, the planet's lost out on about 10 million tons of fish catch. 
    • 20 million people a year suffer from malnutrition.
    • Global governments spend about $27 billion a year on subsidies to the fishing industry, 60% goes towards unsustainable fishing operations.
  • 9.
    • Cause: Commercially valuable, bigger, slower growing species have been overfished. (e.g., tuna, cod, snapper) 
    • Effect: They target large quantities of smaller species of fish with less commercial value. (squid, sardines, oysters, mussels, and shrimp)
    • Less predatory pressure
    • Less competition for food
    • Predators deprived of food source needed in order to re-establish the population
  • 10.
    • Living creatures caught unintentionally by fishing gear.
    • Unlike target species, bycatch is unwanted and often unused.
    • Bycatch may be kept or sold
    • Might be thrown back as discard if not usable.
    • Handling and exposure sometimes injure the bycatch, which may die after being discarded.
    • This affects the current population
    • Influences the species’ opportunity to reproduce.
  • 11.
    • Gillnetting – A invisible to fish fine-filament net used for capturing mainly salmon, cod and sardine. Damages other species. (14)
    Cyanide fishing – Cyanide is used to stun and capture live coral reef fish. Cheap and effective but illegal. (13)
  • 12. Explosive fishing – the use of dynamite or other explosives to kill fish. Causes for major destruction of reef. (15) Long-line fishing – long baited hooks used to catch swordfish, tuna, sharks, birds, and turtles. They are estimated to kill 180,000 birds worldwide every year. (11)
  • 13.
    • Dragging huge, heavy nets along the sea floor. 
    • Large metal plates and rubber wheels attached to these nets move along the bottom and crush nearly everything in their path.
    • Water life forms are very slow to recover from such damage.
  • 14.
    • Preserved areas where species are protected
    • Fishing or catching of other marine animals is prohibited
    • Help species regenerate, to restore population
    • Helps species which are not included in no-take zones to restore population
  • 15.  
  • 16.
    • The farming of aquatic organisms – keeping them under controlled conditions
    • Reduces the worlds dependence on wild stocks of fish
    • Helps to feed the worlds growing population.
    • Negative impact on wild species
    • Ex. – salmon: carnivores which need protein -> comes from forage fish -> salmon wants more forage fish -> impacts survivability of wild salmon
  • 17.
    • The population of breeding tunas has been declining steeply for the past decade
    • Will be wiped out completely in 3 years if nothing is done
    • Tunas that are able to reproduce – being wiped out
    • The size of mature tunas has more than halved since the 1990s.
    • The average size of tuna caught off the coast of Libya has dropped from 124kg in 2001 to only 65kg last year.
    • Industrial fishing is the main reason for the problem
    • WWF is calling for the immediate closure of the Mediterranean bluefin tuna fishery to give the species a chance to recover.
    • Trying to create a marine reserve for bluefin tuna in the Balearic Islands. (17, 18)
  • 18.
    • Problem since 1700s due to human impact – growing population and economy
    • 1890s – dams were affecting salmon runs
    • Hydroelectric and flood-control projects reduce area available to salmon by half
    • Also affected by grazing, irrigation, logging, mining, pollution, urbanization, predators
    • Salmon hatcheries – don’t work (21)
    • Salmon farms – also not very effective (21)
  • 19.
    • http://overfishing.org/pages/what_is_overfishing.php
    • http://see-the-sea.org/topics/commerce/overfishing.htm
    • http://www.treehugger.com/files/2010/08/how-bad-is-overfishing-what-to-stop-it.php
    • http://www.seafoodsource.com/newsarticledetail.aspx?id=4294990550
    • http://www.seaweb.org/resources/briefings/fishdownweb.php
    • http://archive.greenpeace.org/comms/fish/part3.html
    • http://seagrant.gso.uri.edu/factsheets/Bycatch.html
    • http://food.change.org/blog/view/overfishing_hurts_economy_public_health_and_ocean_ecosystems
    • http://www.msnbc.msn.com/id/32222783/ns/world_news-world_environment/
    • http://apesnature.homestead.com/chapter12.html
    • http://www.copperwiki.org/index.php?title=Destructive_fishing
    • http://www.greenpeace.org/international/campaigns/save-our-seas-2/save-deep-sea-life
    • http://www.wri.org/publication/reefs-at-risk/cyanide-fishing
    • http://www.jobmonkey.com/alaska/html/gillnetting.html
    • http://www.tracc.00server.com/Fisheries/blast_fishing/blastfishing_index.html
    • http://www.providence.edu/polisci/students/aquaculture/environmentalimpact.html
    • http://wwf.panda.org/?162001/Mediterranean-bluefin-tuna-stocks-collapsing-now-as-fishing-season-opens
    • http://www.greenpeace.org/international/en/campaigns/oceans/marine-reserves/roadmap-to-recovery/Save-the-bluefin-tuna-of-the-Mediterranean-/
    • http://www.pnwsalmoncenter.org/
    • http://oregonstate.edu/instruct/anth481/sal/crintro1.htm
    • http://www.groundtruthtrekking.org/Issues/Fisheries/Salmon.html
  • 20.
    • http://wwf.panda.org/about_our_earth/teacher_resources/own_goals/overfishing/
    • http://undercovercop.org/wp-content/uploads/2010/05/wwf_liikakalastus_EU_2007_eng.jpg
    • http://www.macalester.edu/environmentalstudies/students/projects/citizenscience2008/japanwhaling/issues.html
    • http://na.oceana.org/en/blog/2010/10/chile-reduces-jack-mackerel-overfishing
    • http://marinebio.org/oceans/conservation/sustainable-fisheries.asp
    • http://veganworldwidenews.blogspot.com/2009_06_01_archive.html
    • http://scienceblogs.com/shiftingbaselines/2008/02/fishing_down_the_food_web_turn.php
    • http://www.smugmug.com/gallery/11627606_JyU7i/1/819830271_ee3vX#819830271_ee3vX
    • http://www.cdnn.info/news/article/a030429.html
    • http://www.wwf.org.ph/gallery.php?filter=3
    • http://www2.convention.co.jp/maguro/e_maguro/e_tuna_facts.html
    • http://web.mit.edu/12.000/www/m2011/finalwebsite/problem/present/tech.shtml
    • http://earthhopenetwork.net/World_Governments_Adopt_Sustainable_Fisheries_Resolution.htm
    • http://serc.carleton.edu/eslabs/fisheries/4.html
    • http://chefsblade.monster.com/news/articles/470-are-fish-farms-the-way-to-meet-growing-fish-consumption
    • http://www.moyolaangling.com/content/?id=31&l1id=22&l2id=30
    • http://ecolocalizer.com/2009/04/15/mediterranean-bluefin-tuna-will-disappear-by-2012/
    • http://wwf.panda.org/what_we_do/footprint/smart_fishing/sustainable_fisheries/bluefin_tuna/tracking_the_giants/
    • http://www.biology-blog.com/blogs/archives/Biology-blog/520525028-Feb-14-2008.html
    • http://www.statesymbolsusa.org/Alaska/Fish_King_Salmon.html