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Bottom Trawling Involves Dragging Heavily Weighted Nets Across the Seafloor

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Bottom Trawling Involves Dragging Heavily Weighted Nets Across the Seafloor Bottom trawling involves dragging heavily weighted nets across the seafloor. It can catch large quantities of fish, but also unwanted bycatch. Damage to the seafloor can result in deadzones and harmful algae blooms. Source: Greenpeace Longline fishing is where fishing vessels trail huge lines of nets through the oceans, with hundreds or even thousands of baited hooks attached along the nets. The average US longline is 28 miles long, but elsewhere they can stretch out 50 miles. Sea birds such as albatross can get hooked and drowned when the lines are near the surface. Source: Fishcount.org.uk; NYtimes.com Researchers believe commercial line fishing may have contributed to a 60 percent decline in shark numbers in Costa Rican waters over the last decade. Source: PBS.org An estimated 50 million sharks are unintentionally caught as bycatch each year, which is about half as many as are killed intentionally for their meat and fins. Source: Mercyforanimals.org Trawling and longline fishing are indiscriminate, meaning that bycatch is also a huge issue. Every year around 650,000 whales, dolphins, seals, sea lions and turtles are killed each year because of the fishing industry - which equals more than one every minute. Source: Oceana.org; TheDodo.com As much as 70% of microplastics found floating on the surface of the ocean are fishing related. A recent study of the “great Pacific garbage patch”, an area of plastic accumulation in the north Pacific, showed that 86% of the macroplastics in this area were fishing nets. Source: The Guardian Between 10-40% of all fish caught is bycatch (estimated), impacting biodiversity. Mahy species, caught as bycatch, are on the brink of extinction. Source: Oceana.org One-third of the fish that are caught are used to feed farmed animals, including farmed fish but also pigs and chickens, further supporting environmental degradation from greenhouse gas emissions, habitat destruction, deforestation, water use, land use etc. Source: Telegraph.co.uk FACT SHEET | FISH AND THE ENVIRONMENT | SEPTEMBER 2020 The number of overfished species has increased three-fold in the past 40 years alone, with the United Nations FAO stating that 87% of the world’s fisheries are either over- or fully-exploited. Nearly a third of edible fish and seafood species have declined by 90%. Source: FAO.org A study from an international team of researchers published in the Journal Science, even predicted that we could actually have fishless oceans by the year 2048. Source: CBSnews.com Around half of all fish consumed globally is farmed. Many farmed species are carnivorous and fed with smaller wild-caught fish leading to more fishing. For example, it can take up to five pounds of ocean fish to produce just one pound of farmed salmon. Source: news.standford.edu Aquacultural overcrowding results in high rates of diseases and infestations, leading to increased antibiotic use. It is estimated that, in the US, farmed salmon are fed more antibiotics per pound than any other farmed animal. Source: NCLnet.org In 2015, a report in the US found more antibiotic-resistant MRSA on shrimp compared to previous tests of pork, chicken, and ground turkey. Source: Consumer Reports Fish farming is responsible for the destruction of natural habitats with farmed shrimp having destroyed 45% of the mangroves in Bangladesh and 50-65% of the mangroves in Thailand. Mangroves are highly effective at sequestering atmospheric carbon. Source: World Rainforest Movement; Aksornkoae, S. & Tokrisna, R. Kasetsart University A two-acre salmon farm produces as much waste as a town of 10,000 people. Salmon farms in British Columbia were found to be producing as much waste as a city of half a million people. Source: Science FACT SHEET | FISH AND THE ENVIRONMENT | SEPTEMBER 2020.
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