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Main Components
Aquatic species
Target Species
Demersal species

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
Seiners
Seiners
These vessels use surrounding and seine nets and comprise a large group appearing in all sizes.

Characteristics
Scottish seiningDrawing of Fly dragging (Scottish seining)
Scottish seining
Species EnvironmentThis fishing method is especially suitable for the capture of both flatfish and demersal round fish either scattered on or close to the bottom.Fishing GearThe 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. As for Danish seining, keeping the rope into close contact with the bottom as long as possible during the hauling is a major advantage and, for this reason, special heavy ropes are normally used. Many Seine nets are very similar in design to Trawl nets. Frequently, however, the wings are longer than on trawl nets.Vessel OverviewIn medium and large sized vessels special rope hauling and coiling machinery is installed on deck. Long ropes (or draglines) is either just coiled on the deck or stored on drums. On modern seiners, hydraulically operated articulated power blocks are used for hauling the seine; on smaller boats, this is done by hand.Fishery Production SystemsSmall scale and semi-industrial.Fishing EnvironmentFly dragging is appropriate for areas where good fishing, "trawlable" bottoms are broken up with patches of hard and rough ones. The catching area depends on the length of the hauling lines and, to a lesser extent, the length of the wings. Fishing depth when using this method ranges from shallow waters less than 50 m to around 500 m in marine waters.Especially in northern regions; not much in use in tropical and sub-tropical regions.Fishing OperationsWhen fish have been detected the vessel steams some distance away, depending on the depth, sea conditions and the concentration of fish. A marker buoy with flag, called a dhan, attached to the free end of the first rope is then dropped over the side. The vessel then steam towards one side of where the fish have been located, paying out rope as it steams. When the vessel has passed the fish it moves across to shoot the seine net. The vessel then heads back to the dan, paying out the other length of ropes. By the time the gear is set, the dan picked up and the end of the first rope retrieved, nearly all the length of rope each side is lying on the seabed, encircling the fish which was originally detected. With the vessel maintaining sufficient way to be just going ahead, (or in cases, after the seiner steamed ahead for some time) both ropes are hauled simultaneously, slowly at first, the ropes herding fish towards the path of the net as they close. When the ropes are about half way closed, as seen from the vessel, hauling speed is increased and the net begins to chase fish just in front of it whilst the ropes continue to herd fish inwards. When the ropes are seen to be nearly closed they are then fast hauled and the net overtakes fish herded into its path. Fast hauling continues until the net is up to the vessel. A minimum of four crew on deck and one in the wheelhouse is necessary if a power block can help bringing the seine on board; at least two more crew members are necessary if the net is brought aboard by hand.
Setting the net
Setting the net
1. Setting the netVessel steams, paying out half the warp, followed by the net and then the remaining warp.
Finish the set
Finish the set
2. Finish the setFinish of the set; ready to haul.
Hauling the net
Hauling the net
3. Hauling the netHauling is part completed, closing the warps and herding fish into path of net.
Closing the net
Closing the net
4. Closing the netThe net is closed, capturing the fish.
IssuesDiscard The main potential negative impact of Scottish 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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