Overfishing victoria,slav,tanya
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  • FAD – fish are known to be attracted to floating devices, thus, use boat as an attraction method and use bait Fish farming – mariculture ( farming of marine organisms) Handline – oldest way, with a hook and bait Harpoon – directly target, used for bigger fish
  • Moderate size no-take zones protect and restore important habitats, plants and animals while at the same time leaving substantial areas of the ocean open to fishing. That is why scientists believe that no-take zones are the ultimate solution of overfishing that can benefit both fish populations and the fishing industry.
  • Aquaculture has an overall positive effect on the environment. It reduces the world’s dependence on wild stocks of fish, provides new jobs, and helps to feed the world’s growing population. However, it does have some negative effects, concerning farming of shrimp and salmon. When the cages are crowded, uneaten feed, fish wastes and antibiotics are released from the cages.  As a source of nutrient pollution, these wastes create high levels of nutrients that increase the growth of phytoplankton and algae.  The eventual degradation of algae drastically reduces the levels of oxygen in the water, which will kill fish or other organisms. 

Overfishing victoria,slav,tanya Overfishing victoria,slav,tanya Presentation Transcript

  • Overfishing Dimitrova, Tanya Karkelanova, Viktoria Prohasky, Slav 10/1 http://www.keaconservation.co.nz/images/stories/overfishing.2.jpg
  • What is overfishing? [1]
    • Catching more fish than can be replaced by reproduction
    http://www.jky.net/doomed/overfishing.gif
  • Consequences [2]
    • many species close to extinction
    • oceanic world under constant stress
    • humans may lose fish as a source of food
    • Decrease in the mean size of fish [3]
    • Example: Atlantic cod: [4]
            • overfished in the 70s and 80s
            • collapse in 1992 (Red List of Threatened Species)
  • Global Catch [3 ]
    • In 1950 – 19 million tons
    • In 1989 – 100 million tons
    • In 2004 – 140 million tons
  • Fishing Down The Food Chain http://upload.wikimedia.org/wikipedia/commons/archive/a/a2/20090326090801!Fishing_down_the_food_web.jpg
  • Why is overfishing BAD? [6]
    • Fishing is bad for people & fish
    • Decline in populations of different species
    • Effort to catch something of commercial value
    • People will have to
    • eat bait
    •  Fish wisely
  • Bycatch [7]
    • Living creatures, caught unintentionally by fishing gear
    •  not wanted, not useful (turtles, sea stars)
    • Usually thrown back into water
    • Might be hurt or might die
    • Inability to take part in reproduction, decline of population
    • Might become food
  • http:// www.greenpeace.or.jp/campaign/oceans/photos/bycatch
  • How to Fish? [8]
    • Dive- caught
    • Fish Attraction Devices (FAD)
    • Fish Farming
    • Handline
    • Harpoon
  • http://www.aolcdn.com/channels/00/02 /49a5aa00-001d3-01cf6-cdbc8767 http://greenlifesaver.files.wordpress.com/2009 /05/salmon_farm_2007-05-19_1310061.jpg http://www.oceanclubresorts.com/mediagallery/diving/Diver%20And%20Fish.jpg
  • How NOT to Fish? [8]
    • Longlining
    • One main line, hundreds of hooks lay from it
    • Bycatch
    • Hundreds of sharks die annually
  • http://swittersb.files.wordpress.com/2010/01/longline.jpg
  • Bottom-trawling
    • Large nets, dragged on the seafloor [9]
    • Catch ground fish and other species [9]
    http://www.duke.edu/web/nicholas/bio217/durkee-eyler-franken/images/trawling-b-a.jpg
    • trawl doors disturb the sea floor
    • muddy water forms
    • - light level is decreased  reproduction is affected
    • oxygen “dead zones” due to phosphorus
    • November 17th, 2004 – United Nations General Assembly = ban on bottom trawling
    What Happens? [10]
  • http://www.bbc.co.uk/blogs/thereporters/richardblack/bottom_trawling_416.gif
  • “ No-take zone”? [13]
    • Parts of the ocean, in which fishermen are restricted from catching any marine animals
    • Such prohibitions preserve organism biodiversity and prevent over-fishing
  • BENEFITS [14]
    • No-take zones increase:
    •  ecosystem resilience, species diversity (biomass, abundance) and body size
    • Conserve habitats and many species, not just the ones that are fished
    • Best type of no-take zones: those of moderate size
  • Impacts of aquaculture on wild fish populations [15]
    • Fastest growing area in U.S. agriculture
    • Negative effect on wild fish populations
    • Wild fish suffer from poor water quality, loss of bottom habitat, and outbreaks of disease
  • Bluefin Tuna in the Mediterranean
  • S.O.S.
    • Where? – Mediterranean Sea
    • Cause :
      • Commercial and illegal fishing [11]
      • Overcapacity of fishing flees [11]
    • Result: - cut in half population (2002-2007) [11]
    • Solution: Ban global trading through Convention on International Trade in Endangered Species  (CITES).
  •  
  • Cod in Newfoundland, Canada
  • HELP ME, PLEASE! [12]
    • Where? - near the Northern American Continent (a.k.a. Newfoundland)
    • Cause :
      • underestimation of the amount of fish there
      • fishing during the migration period
    • Result:
      • Collapse of cod populations
      • area populated by crab & shrimps, not fish
    • Solution: moratorium
  •  
  • Endangered Species [5 ] Wild Common Carp Alabama Shad
  • Does anyone hear me? We’re in danger!!! Silver Shark Chinese Paddlefish
  • http://www.greenberg-art.com/.toons/.Toons,%20favorites/Overfishing.html
  •  
  • Works Cited
    • [1] Koster, Pepijn. “What is overfishing.” Overfishing - A Global Disaster . N.p., 2007. Web. 5 June 2010. <http://overfishing.org/‌pages/‌what_is_overfishing.php>.
    • [2] Koster, Pepijn. “Why is Ovefishing a Problem.” Overfishing - A Global Disaster . N.p., 2007. Web. 5 June 2010. <http://overfishing.org/‌pages/‌why_is_overfishing_a_problem.php>.
    • [3] “The State of the World Fish Stocks.” Profish - Fisheries Factsheet . N.p., 2006. Web. 5 June 2010. <http://siteresources.worldbank.org/‌INTARD/‌Resources/‌Factsheet_2_ Fish_Stocks_FINAL.pdf?resourceurlname=Factsheet_2_Fish_Stocks_ FI>.
    • [4] “Overfishing.” Wikipedia, The Free Encyclopedia. N.p., 3 June 2010. Web. 5 June 2010. <http://en.wikipedia.org/‌wiki/‌Overfishing>.
    • [5] “Endangered Fish Species.” Web Ecoist . Webecoist © 2006-2009, n.d. Web. 5 June 2010. <http://webecoist.com/‌2008/‌11/‌06/‌endangered- fish-animal-species/>.
    • [6] “Bycatch.” Rhode Island Sea Grant Fact Sheets . N.p., n.d. Web. 5 June 2010. <http://seagrant.gso.uri.edu/‌factsheets/‌Bycatch.html>.
  • Works Cited
    • [7] “Fishing Methods.” Fish Online . N.p., n.d. Web. 5 June 2010. <http://www.fishonline.org/‌information/‌methods/>.
    • [8] “Fishing Methods.” Save Our Seas Foundation . N.p., 2010. Web. 5 June 2010. <http://www.saveourseas.com/‌fishingmethods>.
    • [9] What is Bottom Trawl . Marine Conservation Biology, 2003. Web. 5 June 2010.<http://www.mcbi.org/‌what/‌what_pdfs/‌What_%20is_a_Bottom_T rawl.pdf>.
    • [10] “Bottom trawling.” Wikipedia, The Free Encyclopedia . N.p., 29 May 2010. Web. 5 June 2010. <http://en.wikipedia.org/‌wiki/‌Bottom_trawling>.
    • [11 Hance, Jeremy. &quot;Mediterranean bluefin tuna has only three years left unless fishery closes.&quot; mongabay.com . N.p., 14 Apr. 2009. Web. 13 June 2010. <http://news.mongabay.com/2009/0414-hance_bluefin.html>.
    • [12] &quot;No cod? Blame the seals!&quot; Greenpeace International . N.p., 24 Feb. 2005. Web. 13 June 2010. <http://www.greenpeace.org/international/en/news/features/ no-cod-blame-the-seals/>.
    • [13] &quot;What Is a “€œno-take” Zone?: Information from Answers.com.&quot; Answers.com: Wiki Q&A Combined with Free Online Dictionary, Thesaurus, and Encyclopedias . Web. 14 June 2010. <http://www.answers.com/topic/what-is-a-no-take-zone>.
  • Works Cited
    • [14] Professor Terry Hughes, F.A.A. “What are the benefits of no-take zones? How do they work?” James Cook University. N.p., n.d. Web. 14 June, 2010. <http://www.coralcoe.org.au/research-tools/qpwstalks/NO-TAKE%20ZONES.pdf>.
    • [15] &quot;Environmental Impact of Aquaculture.&quot; Providence College - Home . Web. 14 June 2010. <http://www.providence.edu/polisci/students/aquaculture/environmentalimpact.html>.