The Environmental Impact of the Fishing Industry


Fish is one of the most popular forms of animal protein, with over 3.2 billion people relying on it as 20% of their protein intake. This number is even higher in island and coastal regions, with individuals in those areas relying on fish for up to 70% of their protein intake. As consumption continues to increase due to health-conscious consumers, concerns about the ethics of the fishing industry are beginning to arise due to the threat it raises to our oceans.

The fish we consume makes it to the supermarket in one of two ways: commercial fishing or aquafarming. Both of these methods for obtaining fish have considerably negative impacts on the environment. Although the meat and dairy industries are considered by consumers to have the worst impact on our environment, eating fish has awful consequences on the environment due to its large contribution to polluting our oceans and killing its ecosystems. Due to factors including overfishing, pollution, and ocean acidification, scientists have predicted that the oceans could be dead by 2048 with our current pattern of behavior.

Commercial Fishing

The commercial fishing industry commonly operates unsustainably in order to meet the increasing demand for seafood. Primarily caring about profits, the industry overlooks both the sustainability of their practices and the way it affects marine life. The commercial fishing industry was valued at $240.99 billion in 2017, and is expected to reach $438.59 billion by 2026 due to the projected increase in demand from the industry.

The vessels employed by the industry can be over 100 feet in length, and have the capacity to catch hundreds of tons of fish a day. The pure ability of the industry to catch so many fish a day makes it a significant factor towards the decline of sustainable fisheries. Many popular fish today lie on the “Red List” to avoid purchasing due to the threat their species’ face because of the dangerous amounts of the population that fisheries catch. Some of these fish include Bluefin tuna, Atlantic halibut, Atlantic cod, Atlantic salmon, Chilean sea bass, Red snapper, Yellowfin tuna, and more-- the list contains 22 marine species.

Many of the practices and methods of the commercial fishing industry also threaten ocean environments. A common practice used by fishermen is called trawling, in which a net is dragged along the ocean floor. This disturbs the bottom of the seabed and often drags up plants and coral populations with it that provide a vital importance to maintaining the balance of marine ecosystems. The United Nations estimates that 95% of global ocean damage is a direct result of bottom trawling.

Another large threat from the commercial fishing industry is the lost or abandoned fishing gear that is disposed of within our oceans. A report by Greenpeace found that 640,000 tons of fishing gear accounts for the waste in our oceans each year, which is the equivalent of the weight of 50 thousand double-decker buses. Fishing nets actually account for 86 percent of the large plastics within the Great Pacific Garbage Patch. What’s possibly most concerning about this type of plastic is not only does this account for so much of the waste in our oceans, but it’s specifically designed for the purpose of trapping and killing marine life. Each year, “ghost” fishing nets within the ocean kill over 100,000 whales, dolphins, seals, and turtles.

Possibly the greatest ethical and environmental concern to come from the commercial fishing industry is bycatch. Bycatch is defined as “discarded catch of marine species and unobserved mortality due to a direct encounter with fishing vessels and gear.” These unintentionally caught animals often suffer injuries or die when encountering large vessels and mass amounts of animals caught within the same net. Examples of bycatch include dolphins, whales, sea turtles, and seabirds that become hooked or entangled in fishing gear.

Sustainable fishing practices arose due to the bycatch problem many felt uncomfortable with, which was estimated to kill 300,000 whales and dolphins and 250,000 turtles globally each year. However, it’s questioned by many just how sustainable these fisheries tend to be after an interview was conducted with Mark J. Palmer of the Earth Island Institute (the organization behind the “dolphin-safe” logo). Palmer admitted to a conflict of interest between the companies and organizations that receive “dolphin-safe” and related labels by admitting there’s no such thing as truly “dolphin-safe” fishing practices. Every fishery is guilty of bycatch, and the only true thing one can do to ensure their food is “dolphin-safe” is to not eat fish.


To keep up with the increasing global demand for seafood, aquaculture has increased in popularity to yield more fish. Aquafarming is defined as “The cultivation of marine or freshwater organisms, especially food fish or shellfish such as salmon or oysters, under controlled conditions.” The World Resources Institute predicts aquafarming to more than double by 2050 in order to meet its demand, but the potential environmental implications of such are concerning.

One of the most prominent issues to arise from aquaculture is nutrient build up, in which there’s no way to prevent nutrients in the environment surrounding the fish such as dead fish, uneaten food, and feces to accumulate. These wastes are largely nitrogen and phosphorus-based, which causes oxygen depletion in coastal environments and a net loss of marine productivity in certain coastal areas. The included use of antibiotics, pesticides, and added drugs have the potential to destroy the marine environments being used for fishing, causing additional harm to our oceans. These antibiotics can either have direct impacts on sea life when introduced to the natural environment or can cause disease resistance to develop which can be problematic further down the line.

Aquafarming also carries the high risk of destroying natural habitats and ecosystems due to the accumulation of pollutants and rampant disease outbreak in the waters. Because pollutants can accumulate in ponds over time, in the early days of aquaculture ponds were often abandoned, only to be replaced by new ponds. This leaves detrimental, long term effects for the organisms previously residing in the ponds that were used for farming. Diseases such as the bacterially-caused vibriosis and the viral “white spot” disease also led to pond abandonment. This process resulted in the destruction of hundreds of thousands of acres of mangrove forests – ecosystems critical to the production of wild fish and the protection of the coast from storm surges.

Most notably, the transmission of diseases amongst fish kept closely together in aqua farms is both a threat to the fish being farmed and fish in the wild environments. Disease transfer amongst salmon within agriculture is one of the most highly reported circumstances, largely due to their migratory nature. Salmon who live in natural environments where farms are introduced are susceptible to catching diseases such as sea lice or infectious salmon anemia upon swimming close to cages of an aqua farming system. Poor biosecurity and global transfer of salmon larvae helped speed the transfer of the disease from country to country and even continent to continent. This threatens large groups of migrating salmon who live in natural habitats due to the infectious diseases transmitted from farmed fish surrounding them.

Lastly, the mere footprint that raising fish in aqua farms has on our environment is considerably tolling in itself. Raising a ton of fish takes over 8 tons of water, with shrimp production requiring up to ten times more water. Aqua farming now uses up to nearly 70 percent of the global fish meal supply and almost 90 percent of the world’s fish oil .Many of the fish also farmed, like shrimp and salmon, are natural predators and actually require live species of fish for their diet. To produce a pound of farmed fish, it takes five pounds of fish from the ocean to raise and feed these fish. Aqua Farmers have even begun feeding their species larger quantities of ocean fish in order to yield quicker growth production.

As governments and nations worldwide have pledged to work together to implement policies and strategies in response to the environmental impacts of the fishing industry, new strides towards sustainability are being made more than ever before. Fisheries will continue to make improvements towards implementing sustainable practices, but no fish can truly be considered sustainable while the issues of bycatch, waste, and ocean destruction come at the cost of consumption. It’s important to consider the environmental cost of fish consumption going forward until our oceans can be promised safety in our own lifetime.

Scientists have determined that the amount of fish sustainably caught will decrease as much as quarter by the end of the century if greenhouse gas emissions continue at their current rate. This is caused by rising ocean temperatures caused by greenhouse gas emissions, in addition to the impact of overfishing that the fishing industry has on the oceans. Current science suggests that increasing temperatures will have a negative impact on species of phytoplankton, which are relied on as sources of food for many species of fish. With less phytoplankton within our oceans, fish populations will decline at rapid rates, especially with the added factor of overfishing from the fishing industry.

More than half of the world’s oxygen supply comes from marine synthesizers within the ocean, like phytoplankton and seaweed. These synthesizers also absorb fifty times more carbon dioxide than our atmosphere, making them a crucial component to mitigate the climate change occurring due to increasing greenhouse gas emissions. Photosynthesizers are indispensable to our survival, and without them humans and other life forms simply would not have the oxygen necessary to survive on our planet. The ocean plays a profound role in contributing to all life forms on our planet through its contribution to oxygen production and role in absorbing carbon dioxide, which is why it’s so crucial for us to protect.