Danish seine is an old type of fishing for flatfish and whitefish with small vessels. It's fishing using a seine which is a large fishing net that hangs vertically in the water by attaching weights along the bottom edge and floats along the top. Boats equipped for seine fishing are called seiners.
Danish seines are similar to a small trawl net but simply constructed with no otterboards and very long warps. The boat drags the long wire warps and the net around the fish and the action of the warps herd the fish towards the central net.
Danish seining works best on demersal fish which are either scattered on or close to the bottom of the sea. They are used when there are areas with flat but rough seabeds which are not trawlable. It's especially useful in northern regions.
This fishing method evolved in Denmark and is the original seine netting technique from which "fly dragging" was a later development. The operation is much the same as fly dragging except the marker buoy is anchored while hauling, and the warps and net are closed entirely by winch.