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Published byDale Banks Modified over 9 years ago
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Fishing Methods Traditional analogues for modern methods Spears, arrows Active traps Passive traps, fish ponds Hooks Active nets Passive nets Inland & nearshore subsistence fishing spears exploding harpoons
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Old & New Methods Spear Hook-n-line Traps Exploding harpoon Trolling Trolling-n-chumming Demersal Trawl line Pelagic Trawl line 2000 hooks; 3-4% Traps FADs
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Nets Gill Nets Floats & weights Drift nets –Efficiency –Fiber advances –Bycatch –33000km—80% –Banned in 1992 Trawl Nets demersal & pelagic Power needed Beam beam Otter 10-100m opening Echo-sounder sonar
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A comparison between typical trawl catch and a typical gillnet catch associated with the pre-industrial fishing. Note that the cod end of the net on the factory trawler is bigger than the entire boat housing the traditional fisher.
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Table 2.2 Major species of fish caught with otter trawls SpeciesMajor fishing countriesAreas fished Alaska pollockRussia, Japan, South KoreaNorthwestern Pacific USANortheastern Pacific Atlantic codIceland, Norway, RussiaNortheastern Atlantic Blue whitingNorway, Iceland, Russia, Faeroe Islands Northeastern Atlantic Largehead hairtailChina, South KoreaNorthwestern Pacific
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Largehead hairtail (Trichiurus lepturus). Weight to 5 kg, length to 2.3 meters
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Purse Seines Globally, most fish catch…by far Catch fish schooling near surface 100km x 100m Fish must aggregate in large schools Powerful means to deploy & retrieve Dories (50’s) to power block
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Icelandic freezer trawler Svalbakur, capable of catching 60 tonnes per haul
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Purse seine boats beginning a set on a 64-tonne school of Atlantic menhaden in coastal waters of North Carolina.
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Table 2.1 Major species of fish caught with purse seines SpeciesMajor fishing countriesAreas fished Atlantic herringCanada, USA,Northwestern Atlantic Denmark, Iceland, NorwayNortheastern Atlantic capelinIceland, NorwayNortheastern Atlantic Chilean jack mackerelChile, PeruSoutheastern Pacific Chub mackerelChina, South Korea, RussiaNorthwestern Pacific ChileSoutheastern Pacific European pilchardMoroccoEast Central Atlantic Japanese anchovyChina, Japan, South KoreaNorthwestern Pacific Peruvian anchovyPeruSouthwestern Pacific Skipjack tunaIndonesia, Taiwan, Japan, South Korea, Philippines, USA, Palau West central Pacific EcuadorSoutheastern Pacific JapanNorthwestern Pacific Spain, MaldivesIndian Ocean Yellowfin tunaPhilippines, Taiwan, Japan, USAWest Central Pacific Mexico, VenezeulaEast central Pacific EcuadorSoutheastern Pacific FranceWestern Indian
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Catch Amount by type Purse Seine ~50% –Herring,sardine,anchovies,tuna,mackerel Otter Trawl ~17% –Pollock, cod,whiting Lines ~ 9% –Tunas,swordfish,cod,halibut,haddock,etc Pound/trap nets ~8% –Lobsters,crabs Gill Nets~6% –Squid,salmon,billfish
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Technology Echo sounders Synthetic fibers Power Boat range Preservation of catch –Drying/salting icing,canning,freezing
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Artisanal Fishing
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A fisherman in Cochin, India
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The beachfront market of St.-Louis, Senegal
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Fishing technology in Senegal. Wives parcel out the dregs of catches. The best fish are sold to European traders or seafood processors.
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Schematic of modern, high-tech fishing vessel. From left to right: purse seine, squid jigger, long liner, trawl net equipped with sonar to automatically track schools of fish. The factory trawler depicted above is the Alaska Ocean. It is capable of processing more than 600 tonnes of pollock per day into surimi, the protein paste used in imitation seafood products.
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