Tuna in sustainable ocean ecosystems

The sustainability of our seafood is becoming a much talked about issue, from the fresh fish at our local market, to the majestic Bluefin tuna widely considered to be endangered, to concerns about the canned tuna many of us enjoy as a healthy every day snack. You will find information on this site useful in understanding how the issues you might read in the paper specifically relate to the canned tuna in your local supermarket.

  • Check your tuna

    Check your can of tuna

    Check your can of tuna. Does it say “Product of Thailand“? The majority of canned tuna in Australia does. Thailand has developed a very efficient and high quality tuna canning industry with easy access to global markets.

    Thailand currently processes around half of the canned tuna consumed globally. That’s approximately 750,000 tonnes every year. Australia’s share of the global canned tuna market is pretty small by comparison – only around 31,000 tonnes per year.

    Still, that’s a lot of tuna and demand is increasing because canned tuna is such an affordable, convenient and healthy snack – high in protein, low in fat and contains essential nutrients like Omega-3.

  • Where does it come from?

    Where tuna comes from

    Most of the tuna canned in Thailand is caught in the Western Central Pacific Ocean (WCPO). More specifically, most of it is caught within equatorial waters of the WCPO (10N and 10S, and 130E and 150W), and within the national waters of many Pacific Island Countries. The WCPO is regarded as the world’s most robust tuna fishery. Click on the map to enlarge it and see where most of the world’s (and Australia’s) canned tuna is caught.

  • What species is it?

    Although there are many tuna species in the world, the ones most talked about in Australia are Skipjack, Yellowfin, Bigeye and Bluefin.

    skipjack tuna

    Skipjack is the most commonly used species in canned tuna, particularly in Australia. Skipjack in the WCPO is being fished at around 70% of its Maximum Sustainable Yield. This means that the Skipjack catch could be increased with no negative impact on the sustainability of Skipjack stocks. This is mainly because Skipjack lives for a maximum of around four years and matures at about one year of age – so it is able to reproduce before being caught.

    Visit the SPC-OFP’s website for a full Skipjack stock assessment.

  • What species is it? (continued)

    Although there are many tuna species in the world, the ones most talked about in Australia are Skipjack, Yellowfin, Bigeye and Bluefin.

    Yellowfin Tuna

    Yellowfin is also found in canned tuna sold in Australia (but is not always labelled as such). Yellowfin is currently being fished at close to its limits in the equatorial western Pacific, where more than 90% of the WCPO catch is taken.

    This means that although Yellowfin is not currently being overfished, the stock cannot withstand an increase in catch. With continued increases in purse seine fishing, there are concerns about the future of Yellowfin in the WCPO, particularly in the equatorial region. Yellowfin lives for up to seven years and reaches maturity at around two years of age – so it has less opportunity to reproduce before being captured by commercial fishing vessels.

    Visit the SPC-OFP’s website for a full Yellowfin stock assessment.

  • What species is it? (continued)

    Although there are many tuna species in the world, the ones most talked about in Australia are Skipjack, Yellowfin, Bigeye and Bluefin.

    Bigeye Tuna

    Bigeye is not, as far as we’re aware, used in Australian canned tuna. However it is sometimes caught by the same purse-seine vessels that catch Skipjack tuna. Bigeye is at risk from overfishing in the WCPO and scientists are recommending an almost 50% cut in the number of Bigeye caught across the region.

    Bigeye can live to at least 12 years of age and reaches maturity at 3 or 4 years of age. So, like Yellowfin, it is under pressure from commercial fishing because it is being caught at a greater rate that it is able to reproduce.

    Visit the SPC-OFP’s website for a full Bigeye stock assessment.

  • What species is it? (continued)

    Although there are many tuna species in the world, the ones most talked about in Australia are Skipjack, Yellowfin, Bigeye and Bluefin.


    Bluefin tuna species include Southern Bluefin and Northern (Atlantic) Bluefin. Bluefin is rarely (if ever) caught in the equatorial WCPO and is not canned, as its high price make it unattractive for the canned tuna market.

    Bluefin is the largest and longest lived of all tuna species. Both the Southern and the Northern Bluefin are considered by many to be critically endangered and there is much debate by governments, conservationists, scientists and industry about the best way to ensure their survival.

    For more information about Bluefin tuna, visit one of the following websites:

    Australian Fisheries Management Authority (www.afma.gov.au )

    Australian Government Department of Sustainability, Environment, Water, Population and Communities (www.environment.gov.au )

    Commission for the Conservation of Southern Bluefin Tuna (www.ccsbt.org )

  • How was it caught?

    There are many different ways to catch fish. Each method has a different impact on the species it targets, some species it catches unintentionally, and the wider environment where it operates. There are three fishing methods often discussed in relation to tuna from the WCPO.

    Purseseine fishing
    Purse-seine fishing

    Purse-seine fishing accounts for around 70% of all tuna caught in the WCPO. Almost 80% of the purse-seine catch is Skipjack tuna. Purse-seining is where a vessel encircles a school of fish and then draws the net together like a purse. Around half of the purse-seining in the WCPO is deployed on ‘free schools’ where vessels find and chase a school of fish, then encircle it for the catch. Sometimes fish aggregation devices (FADs) are also used. FADs include naturally-occurring objects such as floating logs and attract fish because they offer protection in open waters.

    FADs help vessels to find fish and also increase the volume of fish in each catch, so they reduce fuel consumption and increase productivity. The use of FADs (including logs) in the WCPO is around 50%. When a purse-seine vessel fishes on a FAD, there is usually a higher proportion of Yellowfin and Bigeye tunas (including juveniles) in the catch, though Skipjack still makes up the vast majority of the catch. All of the purse-seining in the WCPO has been ‘dolphin friendly’ since 1991. For more information about how tuna became ‘dolphin friendly’, visit the Earth Island website.

  • How was it caught? (continued)

    There are many different ways to catch fish. Each method has a different impact on the species it targets, some species it catches unintentionally, and the wider environment where it operates. There are three fishing methods often discussed in relation to tuna from the WCPO.

    Longline fishing
    Longline fishing

    Longline fishing accounts for around 10% of all fish caught in the WCPO and targets adult Yellowfin and Bigeye tuna in equatorial waters and Albacore tuna in more southern waters. Longlining is where lines (some up to 80 kilometers long) with up to 3,000 baited hooks are deployed behind the vessel.

    Longline fishing catches more non-target species than purse-seining, including billfish and sharks. In some areas, turtle and seabird interactions with longline gear may occur, causing negative impacts to these species.

  • How was it caught? (continued)

    There are many different ways to catch fish. Each method has a different impact on the species it targets, some species it catches unintentionally, and the wider environment where it operates. There are three fishing methods often discussed in relation to tuna from the WCPO.

    pole and line fishing
    Pole and line fishing

    Pole and Line fishing accounts for around 7% of all fish caught in the WCPO. Live baitfish is used to attract schools of tuna close to the boat, and the tuna are then caught on a hand-held pole and line, catching fish one-by-one.

    This method typically only catches the species that it targets, primarily Skipjack tuna in the WCPO. The need for fresh baitfish from shallow waters means that Pole and Line fishing occurs close to coastal areas, where live baitfish is more readily available.

    There are some concerns about the capacity of baitfish fisheries in the WCPO to support significantly increased Pole and line activity in the region. For a recent paper on this issue, visit the ISSF website .

There are five key questions currently being asked about the sustainability of canned tuna sold in Australia.
Asking these questions helps to determine whether the tuna we eat is contributing to the problem of overfishing.

  • Was it caught illegally?

    Rates of Illegal, Unregulated and Unreported (IUU) activity varies greatly across regions and fishing methods. It is estimated that for purse-seine caught Skipjack tuna in the WCPO, it is less than 5%.

    This is because all purse-seine vessels operate mostly within areas where license agreements are in place, because licensed vessels have a greater incentive to comply with monitoring and catch reporting requirements, and because there is now 100% independent observer and satellite-base vessel monitoring coverage on all purse-seine vessels in the WCPO.

    Independent observers monitor catches as they happen and verify catch reports provided by vessel captains to fisheries authorities. Vessel blacklists are maintained by the Western and Central Pacific Fisheries Commission and by Greenpeace . Many brands check their shipping documentation against these lists to verify that their tuna was not caught illegally. For a detailed report on the extent of illegal fishing globally, visit the MRAG website .

  • Is it associated with bycatch?

    Bycatch refers to non-target or non-fish species caught by any method of fishing. Non-fish bycatch includes sharks, turtles and seabirds. Non-target bycatch includes juvenile Yellowfin or Bigeye tuna in a Skipjack catch (for example).

    The Secretariat of the Pacific Community Oceanic Fisheries Programme (SPC-OFP ) analyses log-book data from purse-seine vessels on bycatch rates of non-target and non-fish species. Purse-seining without FADs has a very low bycatch rate for both non-target and non-fish species. The use of FADs increases the bycatch of non-target species to around 10%. While the bycatch of non-fish species remains very low, some questions remain about the impact of FADs on non-fish species even if they’re not brought on-board as part of a catch.

    The International Seafood Sustainability Foundation is a global partnership between the tuna industry, scientists and environmental organisation WWF. For a report on options for reducing bycatch on FADs, visit the ISSF website .

  • Was it caught on a FAD?

    Purse-seine vessels report their use of FADs and other floating objects to licensing authorities. Based on this data, the SPC-OFP estimates that floating object sets in the WCPO purse-seine fishery averages 50% in any given year. The bycatch of juvenile Yellowfin and Bigeye tuna associated with FADs is putting pressure on Yellowfin and Bigeye stocks. This has lead fisheries management authorities in the WCPO to implement a 3-month seasonal FAD ban in the WCPO. This year the ban will run from 1 July – 30 September.

    Some Pacific Island Countries are joining forces to reduce FAD use by seeking MSC certification for Skipjack caught on free schools in their sub-region. Some brands are asking their suppliers for more information about FAD use and bycatch rates through improved traceability systems. Greenpeace is calling for consumers and suppliers to favour Pole and Line fishing, or purse-seine fishing without FADs. A global industry-lead group called the ISSF is working on measures to minimise the bycatch issues associated with FADs while preserving the efficiency benefits.

  • Was it caught within a proposed marine reserve?

    Map showing proposed pockets in WCPO

    There are 4 ‘high-seas pockets’ in the WCPO. These are areas which lie outside the boundaries of national waters (Exclusive Economic Zones, or EEZs) but are bordered entirely by EEZs. Two of these areas have been closed to purse-seine fishing. Given the strong compliance by purse-seine vessels with the terms of their license agreements in the WCPO, Skipjack tuna is extremely unlikely to be caught by purse-seiners in the areas that have been closed.

    The remaining two areas lie further south than the areas where most purse-seining for Skipjack is undertaken. So, although it is feasible for Skipjack to be caught by purse-seiners in proposed marine reserves, it is unlikely.

    Some brands are seeking information or assurances from suppliers that their Skipjack is not caught within proposed marine reserves.

  • Did Pacific Island Countries receive a fair return for fish caught in their waters?

    The rate of return to Pacific Island Countries from purse-seine fishing varies as each country negotiates licenses separately with the fishing nations concerned. The details of individual agreements are confidential, though it is estimated that the average return from fishery access fees is around 5% of the landed value of the catch.

    There are a number of developments being explored to increase the value of WCPO fisheries, such as implementation of a Vessel Day Scheme to change the way vessel access is priced and catches are monitored, the move by PNA countries to become certified as a sustainable Skipjack fishery by the Marine Stewardship Council , the expansion of domestic fishing fleets to retain profits locally, and building processing facilities in the region to create employment and retain a greater share of the value-adding process. For more information about some of these initiatives, visit the Forum Fisheries Agency website. .

About us

GreenseasThis website was prepared by the people that sell Greenseas canned tuna in Australia. Through our partnership with the Secretariat of the Pacific Community Oceanic Fisheries Programme (SPC-OFP) we have checked with scientists to ensure what we have said on this website is accurate. We also keep in touch with groups like Greenpeace, the WWF and the Australian Government, as their fisheries experts also help us to understand this complex issue. If you have any queries or concerns about the accuracy of the information on this site, please let us know so that we can set things right if need be. The photos on this website have been provided by the SPC-OFP.

Greenseas is contributing to the sustainability of canned tuna in Australia by

  • including more information on the can so consumers can make an informed choice about species, fishing methods and the area of catching
  • including more information on our websites (including this one) about tuna fishing and sustainability
  • working with our suppliers on ways to improve the traceability of our products
  • providing financial support to the SPC-OFP who conduct scientific assessments and provide advice to all those involved in tuna sustainability across the WCPO
  • publishing a commitment to source sustainably caught tuna, including details about where we source our tuna, how it is caught and how we label it
Contact us

If you have any further questions about tuna sustainability, drop us an email .
If we can’t answer it straight away, we’ll ask someone who can.

We can all take steps to ensure canned tuna remains an affordable, convenient, healthy and tasty snack for generations to come.

What you can do

Consumers can make a difference by purchasing tuna with the least environmental impact. In Australia, this means choosing by species (Skipjack), area of catching (WCPO) and by fishing method (Pole and Line or Purse-Seine). So, look for these on the label or on company websites.

What brands and retailers can do

Brands can help by making more information available to consumers about their products, working with suppliers to improve traceability, supporting the science that supports fisheries and conservation management, and supporting industry efforts to reduce bycatch on FADs.

What governments can do

Governments are responsible for implementing conservation measures, managing monitoring and compliance regimes, and adequately resourcing independent scientific research and analysis.

What environmental organisations can do

NGOs (like WWF, Greenpeace and ISSF) can continue to raise awareness among consumers of tuna sustainability issues, and to work responsibly with industry and Governments to find workable solutions where issues are evident.

Recent News

  • Watch the new film 'Oceanic Guardians' about Pacific Islands taking control of their fisheries.
  • Operation Island Chief indicates IUU fishing is in decline in the WCPO
  • MD of the PNG National Fisheries Authority reiterated hopes that PNG will process 100 percent of the tuna caught in its waters within 10-15 years.
  • Regional surveillance operation reports reduction in illegal fishing
  • Links

    For more information about tuna sustainability in the WCPO and globally, browse the following websites:

  • International Seafood Sustainability Foundation
  • WWF Australia
  • Greenpeace
  • Marine Stewardship Council
  • Forum Fisheries Agency
  • Earth Island (Dolphin Safe)