Trawling is a common and effective fishing method used by commercial fishermen around the world. It involves pulling a large, strong net through the ocean, either close to the seafloor or in the open water, to catch large amounts of fish and other marine creatures at once. This method supports the global seafood supply and is responsible for catching a wide variety of species that people eat every day.
Bottom trawling, which drags nets along or near the seabed, mainly targets fish that live on the ocean floor. Some of the most well-known species include cod, haddock, and hake, which are popular white fish used in many dishes. Flatfish such as flounder, sole, and halibut are also frequently caught this way because they live on sandy or muddy bottoms. In addition to fish, bottom trawling catches many kinds of shellfish and invertebrates, including shrimp, crabs, squid, and octopus. These species are highly valued in markets worldwide and make up a large part of the total catch from bottom trawling. Other bottom-dwelling fish like rockfish and blue grenadier are also commonly harvested in different ocean regions.
Midwater trawling works differently, as the net stays in the middle layers of water instead of touching the seabed. This method is designed to catch fish that swim in large groups, called schools. Small pelagic fish such as herring, sardines, and anchovies are the main targets. These fish are not only eaten directly but also used to make fish oil and fish meal for animal feed. Larger fish that swim in open water, including mackerel and some types of tuna, are also caught using midwater trawling. This method is extremely efficient and can capture huge quantities of fish in a single trip.
Although trawling is highly productive, it also brings environmental challenges. Bottom trawling can disturb seafloor habitats, and both types of trawling may catch unintended marine life, such as young fish, seabirds, and sea turtles. To reduce these impacts, many countries have created rules to control trawling activities, such as limiting fishing areas and improving net designs to avoid unwanted catch. Even with these concerns, trawling remains one of the most important fishing methods globally, catching a wide range of fish and seafood that feed millions of people every day. The species caught by trawling cover nearly all parts of the marine ecosystem, from small baitfish to large commercial fish, making it essential to the world's food system.