Overfishing – catching more fish than the ocean can produce – has been an ongoing challenge for fisheries managers for decades. About 25% of US fish stocks are overfished and 90% of global fish stocks are fully or overfished, which has led to the collapse of some very important fisheries and fishing communities.
Certain types of fishing methods destroy or damage the seafloor habitats where fishes and many other seafloor animals live. These fishing methods are notorious for catching large amounts of bycatch – fish, sea turtles, seabirds and marine mammals – and incidentally killing them during operations.
Among all the fishing methods, bottom trawling, which involves dragging a large net across the sea floor, is the most destructive to our oceans. To protect ocean ecosystems from bottom trawling, Marine Conservation Institute has been a world leader in providing solutions to policymakers in the US and abroad.
What is bottom trawling?
Bottom trawling is an industrial fishing method where a large net with heavy weights is dragged across the seafloor, scooping up everything in its path – from the targeted fish to incidentally caught, centuries-old corals. Bottom trawls are used in catching marine life that live on the seafloor, such as shrimp, cod, rockfish, sole and flounder. Bottom trawls are also commonly used to fish seamount species such as orange roughy on the high seas.
Why is it a problem?
Bottom trawling is unselective and severely damaging to seafloor ecosystems. The net indiscriminately catches every life and object it encounters. Thus, many creatures end up mistakenly caught and thrown overboard dead or dying, including endangered fish and vulnerable deep-sea corals that can live for hundreds of years or more. This collateral damage, called bycatch, can amount to 90% of a trawl’s total catch. In addition, the weight and width of a bottom trawl can destroy large areas of seafloor habitats that give marine species food and shelter. Such habitat destructions can leave the marine ecosystem permanently damaged.
What do we do?
Marine Conservation Institute has successfully pushed trawling impacts to the forefront of the marine conservation debate. We produce peer-reviewed science that examines the ecological impacts of bottom trawling, and model deep-sea habitat suitability to advance protection for ecologically important deep-sea areas. We work in the Deep Sea Conservation Coalition to advocate keeping bottom trawls out of vulnerable marine ecosystems (VMEs) and switching from high-impact fishing methods, like bottom trawling, to less destructive fishing methods. As a leader in the California Seamounts Coalition, we also push to protect vital deep-sea habitats off California from dangerous practices like bottom trawling.