Bottom trawling

Beam trawls or Kurr are special pouch-like bottom trawls to fish for brown shrimp and flatfish ( plaice or sole, for example ) in the Wadden Sea. Over 200 years ago they should have been introduced by the Dutch from China. At the mouth of the Elbe, it is only since 1814 in use.

A 9.5 m long spar, called trawl boom, the opening of the net under water to keep them open. About runner-like shoes fish or shrimp boats pull the net over the seabed. The lower edge of the network carries a 10.6 m long rope ( Bleisehm ), which is weighted with lead node and in more modern times, one with old rope ( Schlatting ) wrapped chain is replaced. Each end of the beam shall bear as iron balls and the slide shoe on the sea bed is an iron, the Kurrklaue. The Rollengrundtau under the net opening complained the beam trawl and triggers slides over the seabed impact. This frightened the crabs and flatfish from the ground and can be detected by the network. The network is filleted by the fishermen themselves; it requires 22 kg of yarn, and its length is 17 m.

The WWF criticized on fishing with beam trawl for a high energy consumption, which is necessary for towing, on the other hand the high load of the seabed and its inhabitants through the rollers and skids.