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Methods to catch fish and other aquatic resources, with or without a gear, have always been practiced. Although the fundamental principles, i.e. filtering the water, luring and outwitting the prey and hunting, are the basis for most of the fishing gears and methods used even today, gears and methods have changed significantly over time and their capture efficiency is obviously hardly comparable to that of prehistoric times.
A fishing gear is the tool with which aquatic resources are captured, whereas the fishing method is how the gear is used. Gear also includes harvesting organisms when no particular gear (tool) is involved. Furthermore, the same fishing gear can be used in different ways. A common way to classify fishing gears and methods is based on the principles of how the fish or other prey are captured and, to a lesser extent, on the gear construction.
FAO defines and classifies the main categories of fishing gear as follows:
- Surrounding nets (including purse seines)
- Seine nets (including beach seines and Boat, Scottish/Danish seines)
- Trawl nets (including Bottom: Beam, Otter and Pair trawls, and Midwater trawls: Otter and Pair trawls)
- Dredges
- Lift nets
- Falling gears (including cast nets)
- Gillnets and entangling nets (including set and drifting gillnets; trammel nets)
- Traps (including pots, stow or bag nets, fixed traps)
- Hooks and lines (including handlines, pole and lines, set or drifting longlines, trolling lines)
- Grappling and wounding gears (including harpoons, spears, arrows, etc.)
- Stupefying devices
This classification is being slightly modified to accommodate the most recent development of fishing gears and methods.
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Harpooning
A traditional method, harpooning is still used today to catch large bluefin tuna and swordfish. Fishermen known as "strikers" stand on a special platform that extends out from the fishing vessel. The striker holds an aluminum harpoon, 10 to 14 feet long, attached to a long rope.
The vessel's captain can use spotter planes to find the fish and angle his boat against the sun so the striker can get a clear shot. Once speared by the harpoon, the fish is quickly killed and hauled aboard. Harpooners return to dock the same day to obtain premium prices for their catch.
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Hook and Line
Fishermen stand shoulder to shoulder on the deck, each with a single pole and line in hand. It looks a bit like sport fishing—until the catch begins. Then it's clear that commercial pole-and-lining is extremely hard work. Fishermen with long poles and very short hooked lines catch the fish one by one and yank them out of the water. They whip the line overhead to bring the fish aboard, then give the rod a practiced twist to unhook the fish. The line is back in the water within seconds for another catch.
Tunas, mahi-mahi and other large pelagic fishes are the target species. Some hook-and-liners use artificial lures. Some "jig" to attract the fish, jerking the line to simulate the motion of smaller fish. "Baitboat" hook-and-liners throw baitfish into the water, causing a feeding frenzy near the boat. Baitboats may also spray and splash the water surface, tricking the target fish into thinking there is even more feeding going on.
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Longlining
Thousands of hooks all fish at once when a longliner rolls out the gear. The central fishing line can be 50 miles long, and it is strung with many smaller lines holding baited hooks. After leaving the lines to "soak" for a time to attract fish, longline fishermen return to haul in their catch. Pelagic longlining takes place near the sea surface, targeting midwater fishes like swordfish and tuna. Demersal or "bottom" longlining targets fishes that live closer to the seafloor, like cod, halibut and sablefish.
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Purse Seining
A purse seine is a large net that encircles a school of fish. The bottom of the net is strung with a line that the crew can pull closed. Small boats move out from a mother ship to surround the fish with netting, like cattle in a corral. The bottom of the net is then pulled closed, like a purse (or a hiker's stuffsack). The baglike net is then raised up, trapping the fish inside it. Fishermen have traditionally used this method to capture sardines, herring and mackerel, but purse seines are also used extensively for catching tuna.
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Traps and Pots
Traps or "pots" are baited cages used to attract the catch and hold it alive until the fisherman returns. Often used for lobster, crabs and shrimp, traps are also occasionally used to catch bottom-dwelling fish, such as sablefish or West Coast rockfish.
Traps are made of wire or wood. They have an entrance, a "kitchen" chamber where the bait rests, and a "parlor" section where undersized animals can escape through vents. Trap fishermen usually lay out many traps attached in a line. After three or four days, they haul their pots aboard, releasing any animals that are too small, too large or not the right species.
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Trawling/Dragging
Trawlers drag a cone-shapped net behind a boat. Different types of trawl nets are used to fish in the midwater (pelagic trawling) and along the seafloor (bottom trawling). Pelagic trawling is often used to catch large schools of small fish such as anchovies; bottom trawlers target bottom-living fishes like cod, halibut and Pacific rockfish. Some bottom trawl nets are fixed with chains that slap the seabed, "tickling" fish into the net above. "Rockhopper" trawls are fitted with heavy tires that roll the net along rough, rocky seafloor. In dredging, a related form of fishing, nets with chain-mesh bottoms are dragged through soft sand to catch scallops.
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Trolling
Long rods pull fishing lines behind a moving vessel in the method known as trolling. Fishermen use a variety of lures and baits to troll for different fishes at different depths. Trollers take speedy fishes that will follow a moving lure, such as salmon, albacore tuna, and mahi-mahi. |
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Gillnetting
A gillnet is a curtain of netting that hangs in the water, suspended from floats. Gillnets are almost invisible to marine life and rely on this fact to catch fish. The spaces in the net are designed to be big enough for the head of a fish to go through, but not its body. As the fish startles and backs out, its gills get caught in the net. |
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