Midwater trawling

Midwater (pelagic) otter trawl
1: trawl warp, 2: otter boards, 3: longline chains, 4 hunter, 5: weights 6: headline with floats, 7: pre-net, 8: tunnel and belly, 9: codend

Midwater trawling is trawling, or net fishing, at a depth that is higher in the water column than the bottom of the ocean. It is contrasted with bottom trawling. Midwater trawling is also known as pelagic trawling and bottom trawling as benthic trawling.

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Midwater trawl

In midwater trawling, a cone-shaped net can be towed behind a single boat and spread by trawl doors, or it can be towed behind two boats (pair trawling) which act as the spreading device. Midwater trawling catches pelagic fish such as anchovies, shrimp, tuna and mackerel, whereas bottom trawling targets both bottom living fish (groundfish) and semi-pelagic fish such as: cod, squid, halibut and rockfish.

Whereas bottom trawling can leave serious incidental damage to the sea bottom in its trail, midwater trawling by contrast is relatively benign.

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