Stop Eating Tuna

I saw this story yesterday on the BBC, which reports on the danger of collapse of bluefin tuna stocks, and didn’t cover it then because I thought it was the sort of thing that would get plenty of media attention. The fact that the not-terribly-environmentally-minded US is supporting a 3-5 year ban on tuna fishing in the North Atlantic says the situation is serious.

I am stunned to see today that when I put “tuna” into Google News, I got all of 5 articles on this issue (BBC, a New York Times editorial, Fish Update, the Telegraph, and the Edmunton Sun).

Readers may note that I have never advocated any particular pro-environment course of action, so I hope you will take this request seriously.

As much as I am a sushi-holic (and tuna is a prized offering), I have been avoiding tuna for some time, not so much for the stock collapse issue (I was unaware of that until recently) but because it is very high up the food chain. You consume a lot of ocean food energy when you eat tuna. And believe me, I am not as virtuous on the environmental front as I’d like to be, but for the vast majority of people, food is one area where it is relatively easy to implement changes (and I anticipate it will become more a focus of attention in the next few years).

A crude rule of thumb is that every time you go one step up the food chain, you get only 10% of the calories you’d get by consuming the next lower item (note I am not sure how this is measured, whether by weight or portion size. Carbohydrates and proteins have the same amount of calories per unit weight, but fats have more than two times as many calories per gram as carbs and protein). So say you eat corn-fed beef. It took ten times the amount of corn to produce that unit weight of beef (and that may not even allow for waste, like skeleton and hide).

Tuna is a top predator. I recall reading it can be as high as 10 levels up the food chain, and per the chart below, it is routinely 4-5 levels up. So tuna is one of the most environmentally costly foods. (Anyone who has better factoids on this matter is encouraged to contribute, but directionally, this depiction is accurate, even if the particulars are a bit off).


So please, no more tuna! And (nicely) encourage any restaurant you frequent to stop serving it.

From the New York Times, “The Bluefin Slaughter“:

The hunting of highly valued animals into oblivion is a symptom of human foolishness that many consign to the unenlightened past, like the 19th century, when bird species were wiped out for feathered hats and bison were decimated for sport. But the slaughter of the giant bluefin tuna is happening now.

An international conference that ends tomorrow in Turkey could help to rescue the bluefin, a noble, ocean-crossing predator, from the brink of collapse — or seal its doom through empty promises and inaction. The United States has gone to the meeting urging a ban on bluefin fishing in the eastern Atlantic and Mediterranean. The world should heed it.

Think of a giant bluefin as an 800-pound torpedo of sushi — some of the finest, fattiest, most expensive there is. Since the 1970s, when the sushi craze took off, purse-seine haulers and longline fishing boats and fish hunters in spotter planes have chased the giant bluefin across the world’s oceans. They have been ruthlessly efficient: The worldwide bluefin population has plunged more than 90 percent in the last 30 years.

There are bluefin tuna “farms” — large-scale ranching operations in the Mediterranean, but these are no less destructive than boats on the open seas. Farms catch their fish in the wild, young and small, exploiting a loophole in rules that set limits by weight. The tuna are fattened in pens, like foie-gras geese, using vast supplies of smaller fish whose plundering is its own ecological disaster.

Scientists of the International Commission for the Conservation of Atlantic Tunas recommended last year that the annual catch in the eastern Atlantic and Mediterranean be lowered to 15,000 metric tons to let the fish recover. The commission instead set a quota that was practically twice that: 29,500 tons. The evidence so far suggests that the actual catch this year will be 40,000 to 50,000 tons, said William Hogarth, director of the National Marine Fisheries Service, who is at the commission’s meeting in Turkey to plead for the moratorium.

Blame for the crisis is global. The European Commission has promoted ruinously excessive fishing quotas. The United States is a major source of sushi demand, and must do much more to protect the bluefin in one of its important spawning grounds, the Gulf of Mexico. And a huge slab of raw guilt should be placed on Japan, the world’s most voracious fish consumer, whose appetite for the bluefin has done the most to make it disappear.

And from the BBC:

The US is calling for a ban on the fishing of bluefin tuna in the eastern Atlantic and Mediterranean Sea.

A three-to-five-years ban is being proposed to the International Commission for the Conservation of Atlantic Tunas (Iccat).

The call comes amid deep concerns that the stock may collapse if the level of overfishing continues.

The European Commission recently closed its bluefin tuna fishery for this year after quota limits had been exceeded.

Bill Hogarth, the US delegate and Iccat chairman, said: “We need a determined international effort to save this truly magnificent fish”.

The US Senate has backed Mr Hogath’s calls for a moratorium on bluefin tuna fishing at the Iccat, which is currently meeting in Turkey…

Speaking from Turkey, Dr Sergi Tudela, the head of Fisheries Programme at WWF Mediterranean said:

“The so-called recovery plan that was adopted by Iccat last year, is not a recovery plan – it is a collapse plan, even according to the scientific committee of Iccat,” he told BBC News.

In 2006, to stop stock decline, Iccat scientists advised that the total catches on eastern Atlantic and Mediterranean bluefin stock should not exceed 15,000 tonnes.

The adopted plan, however, set the quota at 29,000 metric tonnes for 2007, nearly twice the scientifically recommended level.

These unsustainable management measures, along with violations of catch limits, illegal fishing and misreporting mean the US and WWF believe a moratorium is the only option to save blue fin tuna stocks from collapse.

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13 comments

  1. Anonymous

    Thank you for this post. Very sad that this story is not getting the attention it should in the media. I hope that other bloggers will pick it up and make the media notice.

    I’m submitting this to reddit.com..

  2. KissTheGoat

    .. and I saw it on Reddit – good to hear about this. You talk about asking restaurants to stop serving it, I’m sure 100x more is sold in cans in supermarkets. Good luck in getting people to break /that/ habit.

  3. techfun

    Most of the canned tuna is yellowfin, skipjack, or tongol, not bluefin. But most fish stocks need a closer look.

  4. Anonymous

    Your reasoning here makes no sense to me. If we fish Bluefin into extinction then we are eliminating a species that is very high on the food chain. Ergo, the food that species would have eaten had it not gone extinct is now available for other species. If you were instead arguing that we need to give Tuna a rest so stocks could rebuild and then we can resume eating them, I would understand. But your claim that its high position on the food chain makes it a “wasteful” method of harvesting calories implies that if we didn’t reduce their numbers, Tuna collectively would consume fewer calories. That’s nonsense, of course.

  5. Yves Smith

    Anon of 7:02 PM,

    No, if you eat tuna, you only get 10% of the food energy of tuna, which is already one of the costliest predators. To be in the same position as the tuna, you’d need to eat what tunas eat.

    The human race is consuming food energy way way out of proportion to anything that is sustainable. Eating food that is high up on the food chain is wasteful. Given how many people are on the planet, it is destructive to the biosphere and ultimately makes it unlikely that advanced civilizations will be sustained.

    I recall hearing Jim Rogers say in the late 1990s that for the Chinese to meet their objective of having everyone eat one more egg a week, world wheat production would have to triple (no wonder he has been long commodities). Jared Diamond, author of Collapse: How Societies Choose to Fail or Succeed,estimates that there will be no first world lifestyles in 30 to 50 years. Nevertheless, top predators (except humans per the discussion below) play an important role in keeping ecosystems in balance.

    I will let esteemed biologist Edward O. Wilson address your argument via his 1993 essay, “Is Humanity Suicidal?“:

    Now in the midst of a population explosion, the human species has doubled to 5.5 billion during the past 50 years. It is scheduled to double again in the next 50 years. No other single species in evolutionary history has even remotely approached the sheer mass in protoplasm generated by humanity.

    Darwin’s dice have rolled badly for Earth. It was a misfortune for the living world in particular, many scientists believe, that a carnivorous primate and not some more benign form of animal made the breakthrough. Our species retains hereditary traits that add greatly to our destructive impact. We are tribal and aggressively territorial, intent on private space beyond minimal requirements and oriented by selfish sexual and reproductive drives. Cooperation beyond the family and tribal levels comes hard.

    Worse, our liking for meat causes us to use the sun’s energy at low efficiency. It is a general rule of ecology that (very roughly) only about 10 percent of the sun’s energy captured by photosynthesis to produce plant tissue is converted into energy in the tissue of herbivores, the animals that eat the plants. Of that amount, 10 percent reaches the tissue of the carnivores feeding on the herbivores. Similarly, only 10 percent is transferred to carnivores that eat carnivores. And so on for another step or two.

    In a wetlands chain that runs from marsh grass to grasshopper to warbler to hawk, the energy captured during green production shrinks a thousandfold. In other words, it takes a great deal of grass to support a hawk. Human beings, like hawks, are top carnivores, at the end of the food chain whenever they eat meat, two or more links removed from the plants; if chicken, for example, two links, and if tuna, four links.

    Even with most societies confined today to a mostly vegetarian diet, humanity is gobbling up a large part of the rest of the living world. We appropriate between 20 and 40 percent of the sun’s energy that would otherwise be fixed into the tissue of natural vegetation, principally by our consumption of crops and timber, construction of buildings and roadways and the creation of wastelands. In the relentless search for more food, we have reduced animal life in lakes, rivers and now, increasingly, the open ocean.

  6. Yves Smith

    kissthegoat,

    Agreed that canned tuna accounts for the vast majority of tuna consumption (ex bluefin). However, restaurant owners and chefs, particularly top ones, get press. If they learn their customers are concerned about environmental issues, and particularly overfishing, they will not only fall into line but will likely talk it up. That at least may influence middle/upper middle class consumers.

    Although Chilean sea bass was never a mainstream item, most restaurants and many fishmongers stopped carrying it once word got out it was severely overfished (and having cooked it, it was the most fault tolerant fish, perfect for entertaining, and it tasted terrific too).

    Canned tuna is now so cheaply priced that it will be hard to wean people off it.

  7. Anonymous

    A large majority of commercial fisheries have never been, and continue not to be, sustainable. Ocean ecosystems simply cannot sustain the fishing pressure humans impose, even in managed fisheries. It’s not just tuna high up on the food web that are suffering from overfishing. The biomass of high-trophic level fishes has declined by two-thirds during the last 50-year period, and with a factor of nine over the century. There are many factors that pressure fishery managers: social, political, economic, and the increasing demand for boidiversity, and all of these rarely diverge at one solution. It’s also a complex problem that’s hard to alleviate since tuna live largely in the open ocean where catch regulation falls upon cooperation of international bodies. Not to mention the difficulty of catching illegal fishing vessels before they do excessive damage, even in stocks that are meant to be left to recover.

    I imagine we’ll see moratoriums on many fisheries in the next couple years. Unfortunately the people studying the problems and finding that we have to stop exploiting marine resources so heavily are rarely the ones that have the political ability to stop the fishery until the fishers actually go out and find that there is nothing left to catch.
    ————
    Christensen, V. et al. (2003) Hundred year decline of North Atlantic
    predatory fishes. Fish and Fisheries 4, 1–24

    Pauly, D., Christensen, V., Dalsgaard, J., Froese, R. & Torres, F. Jr Fishing down marine food webs.
    Science 279, 860–863 (1998)

    Hutchings, J. A. Collapse and recovery of marine fishes. Nature 406, 882–885 (2000).

    Pauly D, Christensen V, Guénette S, Pitcher TJ, Sumaila UR, Walters CJ, Watson R, Zeller D.
    Abstract
    Towards sustainability in world fisheries.
    Nature. 2002 Aug 8;418(6898):689-95.

  8. Juan

    On the opposite end of the chain we have the phytoplankton and detritus eating Atlantic Menhaden, a fish which the attached calls ‘the most important in the sea’ and which has evidently been suffering a particular commercial over-exploition.

    “You’ve never heard of them, but your life may depend on them”
    http://andromeda.rutgers.edu/~hbf/menhaden.htm

  9. Yves Smith

    Anon of 9:56 AM and Juan,

    Thanks for the links. Sadly, overfishing is not going away as a topic, and they will be good references for future posts.

  10. George

    WIth all species of fish being depleted so drastically is it time to recognize the inevitable?

    IT isn’t a species by species problem.
    Their are simply too many people for the oceans to support with natural wild fish.

    We are actually reaching that point predicted where humanity is too large to be sustained by the natural planet.

    either we all start eating farm raised stuff that is the next level lower than solent green or the wild populations of the earth will have their final remianing taters eaten to extinction.

    There is virtually nothing left inthe oceans now. literally.
    people simply don’t realize it is a vast wasteland of oceanic desert now whereas just 20 yrs ago it was still full.

    http://www.vivzizi.com

  11. Yves Smith

    George,

    I agree with your point. If you saw my comment above, with the 1993 E.O, Wilson, humanity is toast. I recall reading that back then, saying that humans were using 20 to 40% of the solar energy. It was obvious that that isn’t sustainable, yet no one seemed willing to connect the dots. The Club of Rome had been wrong, so no need to be cautious. Of course, the Club of Rome was right, but they drew the trend lines a bit too steeply,

    So here we are, 15 years later, with even more people on the planet and everyone wanting to live a first world lifestyle. We are going to go down the tubes as a civilization due to our inability to manage our use of resources. The human race may survive in some form, but the damage to the planet (particularly species loss and pollution) will take millions of years to reverse. Cadmium and lead in the soil? Yikes.

    So yes, mentioning tuna is rearranging the deck chairs on the Titanic. But I’d like to see as many species survive as possible. And a secondary rationale for the post is to educate people as to the cost of eating food higher up on the food chain.

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