WWF Coral Triangle has just released a very informative Youtube movie on tuna:
It gives a good introduction into some of the issues we address in BESTTuna.
WWF Coral Triangle has just released a very informative Youtube movie on tuna:
It gives a good introduction into some of the issues we address in BESTTuna.
Chances are you’ve thrown one of these on your barbecue this summer:
Actually, to just call it “tuna” is misleading, because there are several species of it. If you have ever had a tuna sandwich you will probably have eaten skipjack tuna. It is the cheapest, least tasty, but also the most abundant tuna species: the IUCN is not particularly concerned about it, and the FAO assesses we can catch some more of it without depleting its stock (pdf). The species in the pack in the picture, yellowfin, is doing less well: the IUCN labels the species “near threatened”, and the FAO argues against catch increases of this species. Other species are doing worse or much worse than that: bigeye tuna, for instance, is labelled “vulnerable” 1.
Save the apples, don’t eat pears
So we should all eat skipjack instead instead of yellowfin and bigeye, right? If only life were that simple. Yellowfin and bigeye are often caught as so-called bycatch of skipjack tuna. Many fishers use Fish Aggregating Devices (FADs) that attract all kinds of fish, starting from small fry all the way up the food chain to several species of tuna. When this includes a school of tuna, fishers draw a purse seine net around the FAD and haul in their bounty. Fishing this way, you are likely to catch a lot of skipjack, yellowfin and bigeye at once, where the yellowfin and bigeye you catch is probably still young and difficult to separate from the adult skipjack. And hence yellowfin and bigeye often end up in a tuna sandwich at a young age where they could have had a glorious career as sushi or tuna steak.
Therefore, the FAO recommends not to increase skipjack catches: not because it is concerned about skipjack stocks, but because catching more skipjack will likely have a negative impact on stocks of yellowfin and bigeye. So perhaps to preserve yellowfin and bigeye stocks, the last thing one should do is buy skipjack tuna.
Governments have used all kinds of different policy instruments to manage fisheries, such as days-at-sea restrictions, or individual transferable quota, or a variety of gear regulations. Such instruments, however, are not everywhere as easy to implement, and governments are in a difficult situation themselves. It is often difficult to observe how much fishers have caught. Moreover, if Kiribati limits its tuna catch in order to preserve tuna stocks for the future, fishers gladly move on to the next Pacific Island Nation to fish there. Perhaps retailers, NGOs, and consumers should step in? We could reward fishers who fish more selectively with some certification scheme: guilt-ridden consumers may be willing to pay some extra for guilt-free tuna. But what if that simply increases demand for fish, and thereby fishing pressure?
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Note the neat batik BESTTuna shirts – courtesy of our Bogor partners |
BESTTuna
Last week I was in Bogor, Indonesia, to discuss this problem with colleagues from Wageningen University and other institutes. We were at the kick-off of BESTTuna, a project of Wageningen University together with many other organisations, including Bogor Agricultural University, University of the South Pacific, University of the Philippines, University of California, Santa Barbara, WWF, and Anova Seafood. The objective of BESTTuna is to look deeper into the management problem with skipjack, yellowfin, and bigeye tuna, considering the different countries involved, the different fishing techniques, the companies involved, NGOs, fishers, and so on. Should Indonesia introduce individual tradable quota? Will MSC certification give fishers an incentive to fish sustainably or will it only enhance fishing pressure as green consumers can start eating tuna with a seemingly clear conscience? How can we make sure that Pacific Island Nations cooperate to manage their tuna stocks sustainably? It’s a complex, but therefore also fascinating problem – and it’s one of those problems you’re reminded of every time you enter the supermarket.
Footnotes
1
One of the most depressing cases of tuna overfishing is the southern Pacific bluefin tuna. It is currently at no more than about 15% of its 1973 stock. Bluefin, however, is quite a different story than the species I describe in this post.↩
WWF’s latest Living Planet Report presents a bleak picture, some hopeful trends, an awfully bad indicator and lots of pious words on sustainable development.
Oh boy: the Ecological Footprint
NGOs like WWF love indicators like the Ecological Footprint. Its message seems simple: if we want to continue living the way we do now, we need more planets to offset all the bad thing we do. Alas, it is one of the worst concoctions that ever came out of an econophobic environmentalist’s imagination. At best it tells us things we already know. At worst it suggests policies that are harmful to people AND the environment. It is claptrap. Trash. Ecological Footprint is evil. The objections are legion, but the main ones are:
Ecological Footprint does not tell us how bad impacts are
Suppose we have two pollutants. One will, if it reaches a certain concentration, kill all life on the planet. Theoretically we can reduce its concentration with some technology that takes very little space, but because we think it is too expensive we haven’t installed it yet. (Let’s say we can install some device on the North Pole that sucks the pollutant out of the air.) The other pollutant causes a nasty rash among a small share of the population. Reducing its concentration requires the planting of huge areas of forest, but we can use these forests also for recreation, timber, and all other kinds of uses. Which pollutant should be banned?
EF would say: ban the second pollutant. Not because that pollutant causes a rash, not because EF aims to kill all life on the planet, but because mitigating that pollutant’s emissions takes more hectares than mitigating the first pollutant. So one problem with EF is that it ignores how a given activity affects our well-being, or that of future generations. All that matters is how far we are from a steady state, and this “how far” is measured in hectares. Why hectares? Are they such good indicators of the well-being of humans, or life on Earth in general? No. But it gives you pretty pictures: you can show your readers a picture of Earth besides one or two other planets and tell people we also need the other planets. And then your readers can say: “Oh no! We need two more!” It’s a great propaganda tool.
Ecological Footprint depends strongly on carbon emissions
In fact, EF ignores toxic substances altogether, because, you guessed it, they are so difficult to translate into hectares. The only exception is carbon emissions: after all, we could in theory plant trees to absorb and store carbon. (Please don’t start now that carbon is not a pollutant but plant food, and that anthropogenic global warming is a leftist conspiracy to take away your SUV. Conspiracy theories give me a rash.) This is what the EF assumes: that we need to grow trees in order to absorb all the carbon we emit. No wonder carbon makes up about 50% of the global Ecological Footprint! In case you haven’t noticed: the fact that 50% of the EF is caused by carbon emissions is not the result of the gravity of human-induced climate change (which I agree is serious), but of the assumptions that the EF makes on how we should mitigate those emissions (which may be or may not be realistic but is in NO way related to the consequences of human-induced climate change). Moreover, there are many ways of mitigating carbon emissions, many of which take less space than planting trees: Carbon Capture and Storage, for instance.
Ecological Footprint is biased against cities and trade
If the LPR simply presented the EF as an indicator of whether we can keep up current consumption rates indefinitely or not, it may not necessarily be wrong, although it would be useless: we already know from IPCC, IUCN, and other bodies that we are having impacts that are drastically altering ecosystems, and are likely to limit future generations’ well-being. The problem so far seems to be that it is presented as a quantitative measure of how bad things are, which it is not. However, the LPR (as well as the EF’s proponents) go further than that: they claim cities are evil, and they base that claim on cities’ Ecological Footprint.
The reasoning is like this. Imagine a city that covers 100 km2. Of course it cannot exist on its own: after all, it is a city, population density is high, so it is impossible to feed all the city folk by growing food on the mere 100 km2 covered by that city. So it buys food from the rural areas around it. The inventors of EF claim this is a bad thing. Our imaginary city could have an ecological footprint several times its physical surface area, because all that farmland provides food to the city. So according to EF’s proponents it is unsustainable, and should reduce its footprint to something more in line with its physical size. Cities are parasites on their surroundings, the EF folks claim.
This ‘parasitism’ is nothing more than trade. A farm’s footprint is smaller than its physical area because it only uses a fraction of the food it produces: the rest is sold, mainly to city folk. This is good: farmers can specialize in farming, city folk can specialize in activities for which it pays to be close to other people, such as trade, banking, research, and education. Throughout history, cities have been hotbeds of innovation, of revolution, of new ideas being spawned, spreading, and finding fertile ground.
No wonder EF is also biased against international trade: densely populated countries (read: countries where land is in short supply) like Singapore and The Netherlands import a lot of food and timber from countries that have lots of land. This way everybody can do what he or she is best at. Really, you don’t want to live in a world where everybody grows his own food, fetches his own water, generates his own energy, builds his own house, and pulls his own teeth. Trade enables division of labour, which enables us to do a lot more with the same resources.
Better indicators? Prices!
If EF is so bad, is there any other way to express the state of the world’s environment in one figure? The short answer is: no. The issues are too diverse, and too numerous to be translated in a single figure. The long answer: what should such an indicator reflect? At least it should reflect how serious the issues are, because policy makers will set their priorities with the help of the indicator. Prices may be imperfect reflections of what people want, but they are still way better than an arbitrary variable like surface area. (Why not Joules? Or grams? I know: less pretty pictures.) The indicator should also reflect not only our current happiness, but also our impact on the future. So a country that throws a big party squandering its natural resources should have a lower value than a country that uses the same amount of resources more wisely. The first issue is not in EF, and the second issue only partially (and using, as I said, a poorly suited unit). Gross National Income, which is widely used by economists but also criticized by ecologists, is also a very poor indicator of wealth, mainly because it ignores natural resource depletion. But there are better, less well-known indicators: the latest edition of The World Bank’s Little Green Data Book presents not only Gross National Income of different countries and regions, but also their Adjusted Net National Income, which is GNI minus consumption of fixed capital, and depletion of energy resources, minerals, and forests. And thankfully, the word “footprint” is nowhere to be found.
WWF’s latest Living Planet Report presents a bleak picture, some hopeful trends, an awfully bad indicator and lots of pious words on sustainable development.
The Living Planet Index
The bleak picture is painted by the overall trends in The Living Planet Index, a weighted average of the abundance (or density, or another indicator of well-being) of a ‘basket’ of species. You can argue about the weights each species gets, of course, but the overall message is that most of the species they monitor are still in decline.
The hopeful trends are in the North: rich country LPIs are rising. There could be many reasons for this. Unsurprisingly, the LPR claims that the rising trends in the North are only possible because rich countries ‘export’, as it were, the damaging activities necessary for their consumption to poorer countries. I don’t doubt this is one of the drivers, but I can’t help thinking that it also matters that as we grow richer, we start caring more for the environment. Whether this means that we should all be poor (little consumption of natural resources) or rich (high preference for conservation) is a very, very old discussion in environmental economics.
The LPR also states that just because things are getting better, that does not mean they are going well. The report rightly points towards the fact that Atlantic cod stocks in some places are only a few percent of what they were mid-nineteenth century. Although cods stocks are improving, they could have been a lot better (i.e., we could have had a lot more bacalau than we’re having now). Be careful, however, not to interpret this as that we should strive for pre-industrial levels for all species. After all, this would mean that we should never fish at all. The report does not make this claim explicitly, but such claims are made in other indicators. It is important to keep in mind that biomass levels that give us Maximum Sustainable Yield generally lie at about 20%-50% of what the biomass would have been if we did not fish at all. So if a stock is at 5% of its pre-fishing level it could be at about 10% of its optimal size. Always keep in mind: what do we want? Pre-industrial or even pre-human biomass levels are poor benchmarks for that.
Next post: Oh boy. They’re using the Ecological Footprint
WWF has a new edition of its Living Planet Report out. I promise to read it more carefully in the near future, but what bothers me about it already is their use of the ecological footprint to make their case. Economists have long criticized the use of the EF as a measure of sustainability. I’ll get deeper into the reasons for that in future posts, but the bottom line for me is that it is often interpreted in a normative sense, even though it cannot be used for that purpose. In other words: it only tells you, in a simplified way, whether we can keep up our current way of life, but it says nothing about the consequences of living unsustainable. Therefore, you risk sounding the wrong alarm bells. By the same token, the way it is designed it is strongly biased against cities and trade: two things economists like and ecologists dislike. This goes some way in explaining its popularity but that does not mean it is an accurate indicator.
Anyway, I’ll go deeper into this later.
Edited 13 June 2012: Changed the title. I should have known about the kind of connotations animal limbs can have (pandas, camels). That’s what you get when you’re not a native speaker.