6 Facts You May Not Know About Illegal, Unreported and Unregulated Fishing

Unseen costs of illicit activity at sea extend to ecosystems and communities

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6 Facts You May Not Know About Illegal, Unreported and Unregulated Fishing

Illegal, unreported and unregulated (IUU) fishing significantly harms not only fish populations and ocean health but also people—so much so that in 2017, the United Nations declared June 5 the International Day for the Fight Against IUU Fishing.

To mark this year’s IUU Day, we’re sharing are six problems that illicit fishing causes—a list that highlights the need for stronger national and international laws to prevent, deter and prosecute fisheries crime.

1. IUU fishing costs the global economy billions of dollars each year.

Estimates from a benchmark study published in the journal Marine Policy suggest that 1 in 5 wild-caught marine fish are landed from IUU fishing. Global Financial Integrity, a Washington, D.C.-based think tank that focuses on illicit trade and corruption, says that IUU fishing generates up to $36.4 billion per year in illegal profits, with untold billions of dollars lost to the global economy in unpaid taxes, customs, license fees and numerous other pieces of the legal seafood supply chain. Further, IUU fishing, which contributes to overfishing globally, also disproportionately impacts small island and developing States.

On a sunny day with small puffy clouds in the sky, a man wearing a shirt that says “Fisheries Officer, Solomon Islands” on the back stands on the deck of a large boat, observing as a crane swings a huge net full of fish onto the deck from an adjacent boat, which is large and blue and white. Two other men—one in a grey tank top and the other in a red sun hat and red tank top—look on.
A fisheries officer in the Solomon Islands oversees the transfer of fish from a fishing boat to a carrier vessel.
Francisco Blaha

2. IUU fishing takes a toll on local and regional cultures.

In April 2023, an Associated Press series highlighted how IUU fishing and overfishing of certain species threatened cultural practices. For example, the Senegalese national dish is thieboudienne, a fish and rice pot meal made primarily from local white grouper. But overfishing and increased illegal fishing have damaged coastal fisheries, and the population of this fish that people have eaten for generations has collapsed. Similarly, in the Bahamas, the population of conch, which has substantial cultural and economic value in the region, has been depleted so severely that, according to the Associated Press, within a decade it may “cease to be commercially viable.” Around the world, and especially where governments lack fisheries enforcement resources, coastal communities are suffering from the impacts of IUU fishing.

Four Black women, each wearing colorful clothing and head wraps, sort fish by hand on a rudimentary stone-and-rebar table outside in the sun. Village buildings are blurred in the background.
Women in Senegal prepare fish for market.
The Pew Charitable Trusts

3. Each year, more than 100,000 people die while fishing—a problem exacerbated by IUU fishing.

According to a 2022 FISH Safety Foundation study, commissioned by Pew, more than 100,000 people die annually while engaged in legal commercial or IUU fishing. While fishing is inherently risky, the study highlights how IUU fishing and overfishing exacerbate and contribute to these deaths. For example, in the Indian Ocean off Madagascar, illegal fishing may represent as much as half of the total catch due to IUU activity from the industrial and artisanal sectors. Local fishers have lost revenue due to the drop in accessible catch and have been forced to go farther out to sea, significantly increasing their safety risk and leading to higher levels of mortality.

A white fishing vessel, heavily covered in rust and with extensive rigging, including nets draped into the sea, idles on a glassy ocean.
A vessel previously engaged in IUU fishing sits abandoned off the coast of Gabon after being boarding by enforcement agencies.
Marine Photobank

4. Illegal fishing affects many more people than fishers alone.

While the on-the-water consequences of illegal fishing are clear, it’s not just those going out to sea that have livelihoods in peril. Those who work in related artisanal industries—including boat construction, net repair, ice hauling and fish processing—are all seeing reduced work and revenues. In West Africa, for example, women are the main processers and traders of fish at market, and the reduction of local fish catch due to illegal activities and overfishing is having a negative economic impact on them.

Three Black women—two seated and one standing—are in an open-air, dirt-floor area surrounded by metal tin basins, most empty but some with small dead fish in them. The air is smoky and the beams and frame of a roofless structure are visible around and above the women.
Women in Ghana are shown with the pans they use to sort fish that come off the local artisanal boats. In better times, these pans would be full, each with a different species of local fish. Now, due to heavy IUU activity and overfishing off of West Africa, the haul is increasingly meagre. As one example, with the prized sardinella species in decline, sellers in Elmina, Ghana, now have mostly lower-quality fish to offer, which results in lower income for them and more desperation for the local fishing community.
Frank Day for The Pew Charitable Trusts

5. Illegal fishing can be more destructive to ecosystems than legal fishing.

Illegal fishers often disregard multiple rules at once, including those that prohibit destructive methods. For example, some IUU fishers practice blast fishing—detonating explosives to stun fish and damage their swim bladders—which often kills all marine life in the blast’s radius, causing immense damage to the marine ecosystem. In some places, fishers use cyanide powder to stun—but not kill—colorful tropical fish, which are then sold on the exotic pet market. Cyanide can also bleach or kill coral reefs. 

A mountain in the distance rises from a calm, tropical sea, and both land and water appear blue under a cloudless sky. In the middleground, a small fish trap made of sticks protrudes from the water.
An illegal fish trap located within Bunaken National Park, North Sulawesi, Indonesia, a marine protected area.
Wolcott Henry 2005 Marine Photobank

6. IUU can obscure where the fish you’re eating has come from.

While grocery stores may list where fish are caught, the involvement of multiple countries in fishing activities can often obscure the true source. Some ecolabels can aid in making smart choices, but they rarely tell the full story. Until there is a traceable chain of custody from the time a fish leaves the water to the time it hits the shelf, customers cannot have 100% confidence in the origin country of their fish.

A fish stall offers 9 pink plates filled with a colorful variety of whole, uncooked fish for sale, with workers in jackets, one in pink and one in orange, sitting behind the counter.
A fish stall at the Jagalchi Fish Market in Busan, South Korea offers a variety of fresh seafood options.
FIFA via Getty Images

Fishing is a challenging global problem, but there are ways to address it, beginning with an effective, comprehensive governance or management regime. Enforcing existing laws—including by prosecuting crime and fining those caught breaking laws—would help shift the dynamics at sea. As with any crime, stronger monitoring and enforcement should lead to a decrease in illegal and destructive activity. Regional partnerships with stronger monitoring and enforcement through increasingly sophisticated technologies, such as satellite monitoring, are making a dent.

Additionally, when countries fulfil their international commitments on fisheries governance and work together by sharing information with each other and within own national agencies, it has a positive effect. For instance, in 2016 the United Nations Port State Measures Agreement, which was designed to strengthen and harmonize fisheries enforcement at ports around the world, was ratified and entered into force. Today, more than 100 States are party to the treaty and, as implementation continues, are helping spotlight the provenance of fish being landed.

Those working on fishing vessels need protections, too. The International Labour Organization’s Convention 188 sets requirements for better labor conditions on fishing vessels, and the International Maritime Organization’s Cape Town Agreement, which has not yet entered force, will raise safety standards onboard fishing vessels. Applied together, these three treaties can help turn the tide on IUU.

A Black man in military uniform descends from the blue deck of what appears to be a large boat into a smaller, orange, rubber boat, where a White man is extending a hand to help. Another Black man is at the wheel of the orange boat. All three men are wearing life jackets.
U.S. Coast Guard and Sierra Leone Police Marine Department officers coordinate on a law enforcement boarding on a fishing vessel in the Atlantic Ocean as part of the African Maritime Law Enforcement Partnership mission.
U.S. Coast Guard

Peter Horn is the project director and Gina Fiore is an officer with The Pew Charitable Trusts’ international fisheries project.

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