Bottom trawling

Bottom trawling is trawling (towing a trawl, which is a fishing net) along the sea floor. It is also called "dragging". Bottom trawling can be either benthic trawling or demersal trawling. Benthic trawling is towing a net at the very bottom of the ocean. Demersal trawling is towing a net just above the bottom.

Another kind of trawling is midwater trawling (also known as pelagic trawling). This is where a net is towed higher in the water column. Midwater trawling catches pelagic fish such as anchovies, tuna, and mackerel. Bottom trawling catches both bottom-living fish. It also catches semi-pelagic species such as cod, squid, shrimp, and rockfish. Trawling is done by a trawler. This can be a small open boat or a large factory trawler.