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Gear types: Boat seines
Boat seines
Boat seines
The boat seines consists basically of a conical netting body, two relatively long wings and a bag ahead of the wings, are long ropes which are used to encircle a large bottom area with the purpose of herding (catching) fish form that area.
Vessel types: Seiners
These vessels use surrounding and seine nets and comprise a large group appearing in all sizes.

Danish seiningDrawing of Anchor seining (Danish seining)
Danish seining
Target Species EnvironTarget species are either scattered on or close to the bottom or aggregated.Geartype OverviewThe boat seines consists basically of a conical netting body, two relatively long wings and a bag. An important component for the capture efficiency of boat seines is the long ropes extending from the wings, which are used to encircle a large area. Many seine nets are very similar in design to trawl nets. Frequently, however, the wings are longer than on trawl nets.Vesseltype OverviewThe fishing operation is usually carried out by a larger vessel or by an additional smaller one launched for this purpose. Long ropes (or draglines) either just coiled on the deck, often with the help of a coiling machine or stored on drums. A buoy (preferably brightly coloured) which will be anchored, will be the "marker" and will serve as the fixed point for the hauling of the seine. For net handling of the seine a power block mounted on boom or a deck crane with slewing is used.Fishery Production SystemsSmall scale and semi-industrial.Fishing EnvironThis fishing technique is particularly applicable where there are areas with flat seabed but no large trawlable bottom; a Danish seine can be operated between several rough spots.Especially in northern regions; not much in use in tropical and sub-tropical regions.Fish Technique OperationThis fishing method, also known as "anchor seine", evolved in Denmark and is the original seine netting technique from which "fly dragging" (Scottish seining) was a later development. Basically, the operation does not defer so much from fly dragging except that the marker buoy is anchored while hauling, and the warps and net are closed entirely by winch. The net is set out from an anchored dhan (marker) buoy. The operation is carried out directly by the main vessel, so called "seiner" or from an additional smaller boat. First, one drag line is put into the water, then one net wing follows and, while the seiner turns round in a surrounding move, back to the buoy, the setting continue with the bag of the seine, then the other wing, then, finally, the other drag line. Thus a big area has been encircled by the time the seiner reaches back the anchored buoy (marker) or the smaller auxiliary boat used for the setting is back to the main unit. The next phase is the hauling in of net through the two drag lines by the boat anchored at the marker; the two drag lines are simultaneously hauled with the help of a rope-coiling machine until the bag with the catch can be taken on board the vessel. Decisive for the success of the operation is the fact that the two drag lines must be, as long as possible, kept into contact with the bottom near the opening of the gear for keeping the fishes together between the two lines and herding them towards e the bag of the seine.
Anchor seining
Anchor seining
1. Anchor seiningFollowing the first set from the anchor position, further set are made to cover a circular area for which the anchor is centre.
IssuesDiscard Issue EntryThe main potential negative impact of Danish seining on living resources is when too many small sized organisms and non-target species are caught and sometimes discarded. Such impact can be mitigated by using larger meshes in the bag and/or specific devices being installed on the seine for reducing the capture of small and unwanted organisms.Source of information
Sainsbury, J.C. 1996 “Commercial fishing methods: an introduction to vessels and gears.” Fishing New Books 0-85238-217-0

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