The Scottish fishing fleet catches fish using a variety of methods, based on different types of gear.
Trawl. This is a large net, usually in the shape of a funnel, that is attached to the vessel by wire ropes or'warps' and towed at deep levels behind special boats (trawlers).
Seine. This is a large fishing net that hangs vertically in the water by means of floats at the top and weights at the bottom.
Demersal Trawl. As the trawl net is towed over the sea floor the mouth is kept open by a combination of boards, floats and weights.
Beam Trawl. This is a bottom fishing trawl net, used mainly to catch flat fish, with the headrope attached to a beam towed along the bottom on runners at either end. The net is heavily weighted with chains on the underside and has tickler chains running in front when fishing.
Pelagic Trawl. This is a variant of trawling used to fish at intermediate depths between the surface and sea floor. The vessel's speed when towing its trawl is greater than for demersal species.
Nephrops Trawl. This is generally used by vessels in the 10-25m length group and they often use seine nets as well. If so rigged a vessel can tow 2 or more smaller type trawls (Nephrop twin/multiple trawl).
Demersal Seine. Long warps are attached to the net, one of which is initially fastened to a flagpole attached to a buoy ("dahn buoy"). The vessel moves forward paying out warp, then the net, then more warp to form a rough triangle back to the dahn. The vessel then steams ahead causing the warps to herd the fish into the path of the net, which is winched aboard.
Purse Seine. One end of the purse shaped net is attached to a buoy and the vessel then sails round the shoal paying out the net. On return to the buoy the net is closed at the foot or'pursed'. This gear requires relatively heavy equipment and therefore large boats.
Gill Nets. Sheets of netting that are paid out to form a curtain in the path of on-coming fish. The net is kept vertical by floats and a heavy footrope, the fish being caught in the mesh by their gills.
Great Lines. These are long lines of thin rope with hooks attached at intervals. They are laid along the sea floor. This method is most suitable for uneven grounds where other methods may be impractical.
Creels. These are'pots' that are arranged on the sea floor and used to catch shellfish such as lobsters, crabs and nephrops.
Dredge. This consists of a steel framed mouth attached to a bag of light metal chain. As the dredge is towed along the sea floor metal teeth attached to the underside rake the shellfish (bivalves such as cockles, scallops and mussels) into the dredge.