SNA (Sydney) — As garbage islands floating in the Pacific Ocean have grown to the area of entire countries, Japan and other nations’ use of plastic fishing nets is believed to not only take a major toll on sea life, but is even threatening the future of the fishing industry itself.

In 2018, an article published in Nature Reports found that at least 79,000 tons of ocean plastic–known as the Great Pacific Garbage Patch or sometimes the North Pacific Garbage Patch–was floating inside an area of 1.6 million square kilometers. At least 46% of the garbage patch was comprised of fishing nets. It has only grown in the meantime.

More recently, a study by The Ocean Cleanup, a Dutch nonprofit organization, found that “75% to 86% of plastic debris in the Great Pacific Garbage Patch originates from fishing activities at sea.”

Another report, this time by Greenpeace, found that over 85% of all rubbish on certain seabeds and ocean ridges is “ghost gear”; that is, fishing gear that has been lost or deliberately abandoned in ocean waters. This gear is thought to make up at least 10% of all oceanic plastic pollution and the majority of all large-sized oceanic plastic pollution.

And yet another study, conducted by The Nature Conservancy, the University of California, the Pelagic Research Group, and Hawaii Pacific University, revealed that roughly 45 million kilograms of plastic pollution enter ocean waters each year from ghost gear. Eric Gilman of Hawaii Pacific University commented that “if all that lost gear were fishing line, it would stretch to the moon and back more than five times.”

Japan has long been affected by such discarded plastic. In the first half of 2015 alone, more than 15,000 plastic containers, many likely used by fishermen, had washed up onto the nation’s beaches.

This is unsurprising, not only due to the excessive use of plastic by neighboring countries like China and South Korea, but also because Japan itself makes heavy use of lightweight plastic equipment in its own fishing operations.

A study published this year in Scientific Reports has identified Japan and mainland China as the two largest sources of plastic pollution in ocean waters, following analysis of more than two hundred plastic objects with identifying marks such as addresses, language, logos, etc. The authors explain that Japan’s fishing industry, along with that of the United States and its Asian neighbors, are probably collectively responsible for about 87% of the plastic pollution in the Great Pacific Garbage Patch.

Most of Japan’s fishing nets and gear are made of lightweight plastic. Nylon is a popular choice because it is stronger, cheaper, and more durable than traditional rope nets. Unfortunately, nylon does not decompose when it is discarded into the ocean.

Last year, the Tara-Jambio Microplastics Mission, a French-Japanese collaboration, set out to “assess the plastic pollution of the Japanese coasts, on the surface and in the sediments,” collecting hundreds of samples to be analyzed. The study concluded that “100% of the samples processed contained microplastics and, among other things, various particles, polymers, polystyrene fragments, secondary microplastics, or other elements used in fishing and oyster farming.”

A Nature Reports article published in September further confirmed that “Japan was the most identified country of origin for floating plastics collected from the [Great] Pacific Garbage Patch in both 2015 (36%) and in 2019 (34%).”

Unfortunately, it is often difficult to assess which nations and corporations are most responsible for ocean plastic pollution, since fishing gear is routinely not marked, and hence, unidentifiable. Furthermore, because of ocean currents, litter can travel thousands of kilometers every year, complicating individual government clean-up responsibilities and cost calculations.

Japan is estimated to dispose of over 100,000 tons of rubbish that washes ashore on its coastlines annually, and this number is set to rise with every delay in implementing pollution policies and regulations for its fishing industry.

According to the Organization for Economic Cooperation and Development (OECD), in 2018 the government spent more than ¥135 billion (US$1.2 billion) financing services for its fisheries sector and a further ¥163 million (US$1.5 million) via policies “directly benefiting individuals and companies in the fisheries sector,” which was an increase of 64% since 2014.

Government support is unsurprising, considering that the nation’s fishing industry is worth approximately US$14 billion, and employs more than 135,000 people at over 2,000 fishing ports around the country.

Nevertheless, the continued use of plastic nets and containers in fishing activities, and the abandonment of gear into the ocean, not only leads to environmental catastrophes but also threatens the longterm survival of Japan’s fishing economy.

Each year, an estimated 100,000 marine animals die due to plastic pollution. The World Wildlife Fund (WWF) has warned that ghost gear is “responsible for the loss of commercially valuable fish stocks, undermining both the overall sustainability of fisheries as well as the people who depend on fish for food and livelihoods.”

In the same vein, the SeaDoc Society, an American nonprofit organization, revealed that just a single discarded fishing net “might kill almost US$20,000 worth of Dungeness crab over ten years.” This is particularly concerning in light of Greenpeace’s finding that over 640,000 tons of nets, lines, pots, and traps used in commercial fishing are abandoned in ocean waters annually.

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