Fished in more than 70 countries, tuna are marketed in fresh, frozen or canned form.

Tuna are among the world’s most popular fish and therefore among the most commercially valuable. Fished in more than 70 countries, tuna are marketed in fresh, frozen or canned form. Tuna species are critical to both commercial and recreational fisheries. But because of high demand for this fish, many stocks are exploited to full capacity—or overfished.

WWF focuses on transforming the global tuna fisheries market and improving the way they are managed. Through our work with the Marine Stewardship Council (MSC) and International Seafood Sustainability Foundation (ISSF), we help global tuna fisheries implement more sustainable practices, which ensures that this valuable resource is harvested responsibly, yielding benefits for ecosystems and livelihoods. We prioritize seven tuna populations with the highest market-value and therefore the greatest vulnerability to overfishing: the Atlantic, Southern and Pacific bluefin, bigeye, yellowfin, albacore and skipjack tuna.

Running a tight ship

The network of cameras on purse-seine tuna vessels, combined with the enhanced monitoring system, prevents illegal, unreported, and unregulated catches from entering the marketplace.
Workers sorting tuna

Why It Matters

  • Tuna are Valuable

    Once considered a low-value substitute for other fish like salmon and sardines, tuna catches have been increasing rapidly ever since canned tuna took off in the 1970s. World tuna catches have been increasing constantly and rapidly. The U.S. alone imported 314,863 metric tons of tuna worth $1.3 billion in 2010.

  • Demand Continues to Grow

    Fresh and frozen tuna consumption has increased over time, especially in North America, Japan, Western Europe and emerging economies. As a result of globalization of food culture and health food preferences, fresh tuna is now prevalent in restaurants and supermarkets worldwide. Your favorite tuna melt sandwich likely comes from either skipjack or albacore, while the tuna you grill or find in sushi is yellowfin, bigeye or bluefin.

  • Tuna are Key Marine Predators

    Tuna are a top predator and food source in the marine food chain and help to maintain a balance in the ocean environment. Ocean predators keep populations of marine life in check to prevent an upset of the ecological balance. Overfishing poses serious threats as loss of predators, like tuna, allows populations of prey species to expand. This then can lead to a destabilized food web and marine environment.



Bycatch of a leatherback turtle at a tuna fishery in the Atlantic Ocean.


According to the United Nations, longline fishing has one of the highest bycatch rates of any gear used to fish for tuna. The average bycatch rate is more than a quarter (28%) of the total catch. In the Pacific Ocean, for instance, millions of baited hooks are set each year on longlines in order to catch tuna and other fish that swim deeper like swordfish and mahi mahi. However, sharks, marine turtles, billfish, seabirds, dolphins, juvenile fish and other fish species also get hooked. The bycatch problem is perhaps most sensitive for marine turtles, especially the critically endangered Pacific leatherback turtles.


Ineffective Management

United Nations Fishing Agreements have helped create numerous regional fisheries management organizations (RFMOs), but due to their voluntary nature, they have been unable to effectively regulate high seas tuna fisheries in a sustainable way. The number of fishing vessels keeps increasing while the tuna populations remain the same and/or are decreasing. The skipjack tuna—while quite resilient and representing 90% of the canned market—could slip into a vulnerable state if improperly managed. Bluefin tuna have been overfished to near extinction globally. If not managed effectively, the world’s tuna fisheries will be faced with an ecological disaster.


Yellowfin tunas

Driven by increasing demand for tuna, fishing pressure has negatively impacted tuna stocks. For instance, in the Coral Triangle region, two of the key tuna species, bigeye and yellowfin, are now on the verge of becoming overfished. Overfishing of these key marine predators can upset the ecological balance of this the global center of marine biodiversity.

Pirate Fishing

Illegal, unreported and unregulated (IUU) fishing, also known as pirate fishing, is a direct threat to the sustainability of global tuna stocks. This modern day piracy threatens the capacity of regional fisheries management organizations (RFMOs) to protect tuna fisheries by impacting the ability of scientists to assess the health of tuna stocks. This jeopardizes the effectiveness of science-based management and conservation measures and blocks the ability of nations to monitor and enforce compliance.


What WWF Is Doing

Bycatch de-hooker

Here WWF demonstrates how to use a bycatch de-hooker to a longline tuna fishing boat crew.

Improving Gear

WWF has worked with the Inter-American Tropical Tuna Commission (IATTC) and others to replace traditional type J hooks with “circle” hooks. The circle hooks can still maintain the target catch of tuna, while substantially reducing the bycatch of marine turtles. Circle hooks are less likely to be swallowed by turtles than traditional J-shaped hooks, and are also easier to unhook from an inadvertently snagged animal. We also work to train fishing communities in the use of de-hooking tools and the effective release of captured turtles.

Loggerhead Turtle

International Seafood Sustainability Foundation

In 2008, WWF joined with global canned tuna processors, non-governmental organizations and marine scientists to found the International Seafood Sustainability Foundation (ISSF). The ISSF advances the use of science-based initiatives for the long-term conservation and sustainable use of tuna stock, reduction of bycatch and promotion of biodiversity and ecosystem health. The ISSF provides a broad platform for industry leaders, governments and non-governmental organizations to work together to address the depletion of tuna. The 21 tuna companies participating in ISSF represent more than 75% of the global canned tuna industry by volume.


Promoting Sustainable Practices

WWF works with other NGO’s and the fishing industry to transform tuna fishing into a sustainable business, particularly through sustainable certification of tuna fisheries according to the Marine Stewardship Council (MSC). WWF promotes sustainable fishing practices by influencing recovery plans for near depleted species, combating pirate fishing, and creating incentives for fishing practices that reduce harmful bycatch. We also partner with governments and regional fisheries management organizations (RFMOs) to advocate for stricter management plans to help recover depleted stocks of tuna species.



How You Can Help