fishing methods traditional analogues for modern methods spears, arrows active traps passive traps,...

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

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

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

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.

Table 2.2 Major species of fish caught with otter trawls

Species Major fishing countries Areas fished

Alaska pollock Russia, Japan, South Korea Northwestern Pacific

USA Northeastern Pacific

Atlantic cod Iceland, Norway, Russia Northeastern Atlantic

Blue whiting Norway, Iceland, Russia, Faeroe Islands

Northeastern Atlantic

Largehead hairtail China, South Korea Northwestern Pacific

Largehead hairtail (Trichiurus lepturus). Weight to 5 kg, length to 2.3 meters

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

Icelandic freezer trawler Svalbakur, capable of catching 60 tonnes per haul

Purse seine boats beginning a set on a 64-tonne school of Atlantic menhaden in coastal waters of North Carolina.

Table 2.1 Major species of fish caught with purse seines

Species Major fishing countries Areas fished

Atlantic herring Canada, USA, Northwestern Atlantic

Denmark, Iceland, Norway Northeastern Atlantic

capelin Iceland, Norway Northeastern Atlantic

Chilean jack mackerel Chile, Peru Southeastern Pacific

Chub mackerel China, South Korea, Russia Northwestern Pacific

Chile Southeastern Pacific

European pilchard Morocco East Central Atlantic

Japanese anchovy China, Japan, South Korea Northwestern Pacific

Peruvian anchovy Peru Southwestern Pacific

Skipjack tuna Indonesia, Taiwan, Japan, South Korea, Philippines, USA, Palau

West central Pacific

Ecuador Southeastern Pacific

Japan Northwestern Pacific

Spain, Maldives Indian Ocean

Yellowfin tuna Philippines, Taiwan, Japan, USA West Central Pacific

Mexico, Venezeula East central Pacific

Ecuador Southeastern Pacific

France Western Indian

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

Technology

• Echo sounders

• Synthetic fibers

• Power

• Boat range

• Preservation of catch– Drying/salting icing,canning,freezing

Artisanal Fishing

A fisherman in Cochin, India

The beachfront market of St.-Louis, Senegal

Fishing technology in Senegal. Wives parcel out the dregs of catches. The best fish are sold to European traders or seafood processors.

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.