Bottom trawls are highly used practices in the fishing industry. Specifically, bottom trawling is focused on harvesting the shrimp and fish that live at the sea floor. Heavy nets are dragged along, with additional weights and hard rubber wheels to collect fish. These deep sea fishing strategies are major contributors to the fishing economy worldwide. The conflict arises that over-use and over-exploitation of areas with bottom trawling and dredging can cause detrimental effects to sea floor organisms. Many issues surround bottom trawling such as the environmental impacts on the sea floor and excessive bycatch. At the present, there is no possible way that our society can sustain its current fisheries without bottom trawling. However, the question still lies: should bottom trawls and dredging be banned globally?
Bottom trawling has extreme impacts that affect the benthic environments of the sea floor. For example, the rollers on the netting are responsible for crushing and burying sea floor animals. Bottom trawling also has long lasting, significant impacts on deep sea corals. Stony corals in deep waters are slow to recover and very vulnerable to the impacts of trawling. Deep sea coral habitats are constantly destroyed by the drag and pressure of the rollers. These changes, created by excessive bottom trawling, exploit the original sea floor organisms that would reside in that area.
Another factor that relates to the flaws of bottom trawling is excessive bycatch. Bycatch is defined as: the accompanying catch of fish and other animals not targeted by the fishing gear. Usually, bycatch is discarded off the ship, dead or alive. Bottom trawling has one of the largest amounts of discard practices in areas such as the western Mediterranean Seas where about fifty percent of the catch was discarded including multiple fish and crustacean species. Although bycatch is a major issue of bottom trawling, there have been some alterations in the trawling nets to decrease the numbers. Bycatch reduction devices (BRD’s) started twenty years ago and have made large strides in the fishing industry. There was a fifty-six percent reduction in bycatch when comparing two fishing boats: one with BRD’s and one without. The changes made included modifications to the gears to allow organisms to escape during fishing and proper handling techniques to reduce fish bycatch mortalities.
Although fish monitoring is a major factor for making strides to end trawling in the future, environmental acts and provisions are in place to limit trawling around different coastlines. New Zealand has banned all bottom trawling at specific sites. Currently our fishing economic stability cannot sustain without trawling, globally. Does this mean that we should continue trawling even with regulations and laws? The answer is up to you.
-by Francesca Koethe
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