Editing Trolling (fishing) (section)

==Commercial trolling==
Commercial trolling vessels catch fish by towing astern one or more trolling lines. The trolling lines are [[fishing line]]s with [[Bait fish|natural]] or [[Fishing lure|artificial baited]] [[Fishing hook|hooks]] trailed by a vessel near the surface or at a certain depth. Several lines can be towed at the same time using outriggers to keep the lines apart. The lines can be hauled in manually or by small winches. A length of rubber is often included in each line as a shock absorber. The trolling line is towed at a speed depending on the target species, from 2.3 knots up to at least 7 knots. Trollers range from small open boats to large refrigerated vessels 30 meters long. In many tropical [[Artisan fishing|artisanal fisheries]], trolling is done with sailing canoes with outriggers for stability. With properly designed vessels, trolling is an economical and efficient way of catching [[tuna]], [[mackerel]] and other [[pelagic fish]] swimming close to the surface. Purpose-built trollers are usually equipped with two or four trolling booms raised and lowered by topping lifts, held in position by adjustable stays. Electrically powered or hydraulic reels can be used to haul in the lines.<ref>[[FAO]]: Fishing Vessel type: [http://www.fao.org/fishery/vesseltype/360/en Trollers]</ref><ref>{{cite web| url = http://www.fao.org/figis/servlet/IRS?iid=7979| title = Drawing (FAO)| access-date = 12 June 2010| archive-date = 24 September 2015| archive-url = https://web.archive.org/web/20150924142201/http://www.fao.org/figis/servlet/IRS?iid=7979| url-status = dead}}</ref>

<gallery mode=packed style=float:left heights=180px>
File:Drawing of a troll vessel.gif|Diagram of a commercial troll vessel using outriggers to tow trolling lines
File:Trolling photo Atlantic.jpg|[[Fishing vessel]] trolling for [[tuna]] in the Atlantic
File:Pacific ocean-fishing for tuna-commercial trolling vessel.jpg| Trolling for tuna in the Pacific
File:Trolling illustration, Historic American Engineering Record.png|Commercial trolling in Alaska
</gallery>
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Commercial trolling for tuna is more successful near [[Ocean bank (topography)|offshore banks]] than in open water areas, and is also enhanced in the vicinity of a [[fish aggregation device]] (FAD).<ref>Buckley RM, Itano DG and Buckley TW (1989) [http://www.ingentaconnect.com/content/umrsmas/bullmar/1989/00000044/00000002/art00038 "Fish Aggregation Device (FAD) Enhancement of Offshore Fisheries in American Samoa"] ''Bulletin of Marine Science'', '''44''' (2): 942-949.</ref>