Lester Brown is the Founder and President of the World Watch Institute.


Can aquaculture take pressure off overexploited ocean fish docks, or has it added pressure on ocean fisheries?

There's been a tendency to focus on salmon and shrimp farming. Even though in quantitative terms they represent maybe two million tons out of the 40 million ton global aquacultural output. There are particular environmental problems with salmon for example that have to do with the use of antibiotics that have to do with concentrating a lot of waste in a small area, usually offshore areas. There are disease problems and questions about the quality of farmed salmon versus wild salmon, for example, so there've been a number of issues that have come up. Environmental issues probably have not gotten the attention they deserve yet, in terms of industry being able to effectively deal with those concerns. Shrimp farming is the same sort of issue.

A lot of the mangrove forests have been destroyed in various areas, particularly in Southeast Asia, countries like Thailand, for example, for shrimp farming. This a basic loss because mangrove forests play an important role in protecting and buffering the relationship between the ocean and low-lying land areas, particularly controlling floods and storm surges and so forth. It's brought another set of environmental problems that are of concern and that may be quite costly over the long term. But when we look at the global picture, we see that the bulk of fish farming does not have quite the same sort of environmental problems, meaning the cultivation of omnivorous fish like carp in China which totally dominates world aquiculture in terms of production. Catfish in the United States is also huge in aquaculture. In volume, it is by far the largest aquacultural operation in the U.S.

Can aquaculture help solve the problem of overexploited ocean fisheries and feed the world, or is it an excuse to mismanage wild fisheries? How are they connected?

We certainly have to manage oceanic fisheries better than we are now, because they have been a growing source of animal protein for the world's people for close to a half-century. The fish catch went from 18 million tons in 1950 to 90 million tons, a five-fold increase by 1990. That was a major increase. The oceanic fish catch overtook world beef production. Even today world beef production is about 52 million tons a year, whereas the oceanic fish catch is something like 90 million tons. We have to manage oceanic fisheries well, because they are an important source of animal protein and diets around the world. It's much more important in some countries and regions than in others, but important worldwide none-the-less.

Once we hit the limits with oceanic fisheries we can shift to fish farming, and that's exactly what we did when we went from hunting and gathering to farming. We used to hunt our animal protein and now we grow most of it like livestock, poultry, pigs, and so forth. We need to keep in mind that when we make the shift and we put fish in ponds, in nets, or enclose them, we have to feed them. When you grow salmon, you not only have to feed them you have to feed them animal protein and that usually means fishmeal. Some of that fishmeal comes from the fish processing industry. When fish are dressed and filleted, the waste is simply ground up into meal and fed to predatory fish like salmon. We've been using fishmeal as an animal protein supplement for a long, long time. Originally it was for pork and poultry, but now it's also for salmon farming. We're also catching a lot of small fish like herring, anchovies, and others that are used to feed salmon. That's not a particularly good ratio because you are using a reasonably high quality animal protein to produce another animal protein; the conversion is not so efficient.

It's omnivorous fish that are being fed grain or soybean meal when the U.S. Department of Agriculture, for example, does the catfish report, and we produce about 600 million pounds of catfish a year now. That is a good two pounds for every American. When they do that report, they have the principal inputs into the industry, and the costs. The ration for catfish, which is mostly corn and soybean meal, is basically the same as it is for the broiler industry. The conversion rate is actually a bit more efficient with catfish than it is with chickens. So we get low cost seafood from catfish, and it's a pretty good quality. The breeding improvements in catfish have produced a fish that is actually widely consumed and served in many restaurants around the country. China, however, they've gone a step further. China's been fish farming for least two maybe 3000 years. It goes way back; there's a long history. They have evolved over time a particular carp culture.

They have four types of carp in the same pond, and one species feeds on phytoplankton, algae, and other things. Another one feeds on zooplankton, which are tiny organisms in the water. Both of these are filter feeders. Then there's a grass carp that feeds on any grass or vegetation that grows in and around the pond. There is also a common carp, which is a bottom feeder, and feeds on all the detritus from the other species of fish. It's really a rather efficient fish production process. They feed the carp grain and soybean meal, but they also fertilize the ponds often with duck or pig manure. This helps produce the phytoplankton and the zooplankton that two of the species fish on. So, in terms of efficiency, this model's in a class by itself. This is why today, China's producing around 15 million tons of carp per year, which is very substantial.

Worldwide aquacultural output now is somewhere around 40 million tons, and the oceanic catch is around 90 million tons. The 90 million tons is probably not going to increase very much, but the farmed production probably will. It takes land and it takes water, and of course feed. It takes land even for the ponds themselves. In this country, catfish farming is concentrated in the state of Mississippi. We have about 170 square miles of land with nothing but catfish ponds. So that's land that much of it was once producing rice, for example, in the Mississippi Delta area. It's now producing catfish. In China, which totally dominates world aquacultural output, there must be 12 million acres or 5 million hectares in carp ponds and other ponds. Another form of fish farming that's quite common in China and also Japan is the production of shellfish: oysters and clams. These are in environmental terms, the least intrusive of any of the farmed fish seafood.

They're grown in coastal regions in saltwater, and they filter the water and obtain their nutrients from that. So that's one of the big "pluses". In some countries, almost all the oysters and clams today come from farming rather than from natural beds. Here in this area, the Chesapeake Bay, at one time produced 100 million pounds of oysters per year. It's now down to less than 3 million pounds per year. There was a time, a few generations ago, when farmers on the eastern shore of Maryland used to feed oysters to their pigs to fatten them. The oysters were so abundant, and so they used them to convert some of them into pork.

Is there any similarity between the mind-set that contributes to overexploited fisheries and the mind-set that supports the advancement of fish farming?

One of the difficulties we have throughout the economy, it's evident in oceanic fisheries and fish farming, is a lack of understanding and perhaps respect of how natural systems work. Over-fishing has become commonplace. Probably 70% of all the oceanic fisheries today are being fished, at or beyond their capacity. If they're beyond their capacity it means their stocks are shrinking and they're headed for collapse. In fish farming, which has grown so rapidly over the last two decades, we see a similar disregard for natural systems. The feeling that we can somehow farm fish without thinking very much about the environmental consequences is a problem that exists in the world today. Why are we, now 6.3 billion of us, in so much trouble on the environmental front? What we're doing is creating a bubble economy by over consuming natural capital.

That's what deforestation is all about, or over-fishing, or over-plowing, or over-grazing, or over-pumping. When you look at the global economy through an environmental lens, this bubble becomes quite clear. The food sector is particularly vulnerable because it depends on over-fishing, on over-pumping, on over-plowing, and on over-grazing. Let's look at over-pumping, for example, at aquifers which are now widespread throughout the world. It's an interesting practice, because it's an effort to satisfy our food needs today that almost guarantees a future drop in food production when aquifers are depleted. The same is true for oceanic fisheries. We keep taking more and more fish. The level of fishing today that sustains us is such that it almost guarantees the future collapse of fisheries. That's exactly what's happening.

Are shrimp or salmon a viable food source to feed the world's population?

In looking at the need for animal protein, including that from seafood, we need to think about the efficiency with which we produce it. As we look at salmon in particular we see that salmon and other predatory fish like trout are among the least efficient converters of feed. We're beginning to see some of the limits on salmon production because of the limits of the fishmeal supply to feed them. Fish processing plants and fisheries that provide the smaller, less desirable fish have their own limits. We need to think about how to most efficiently satisfy the growing need for animal protein, in this case, the growing demand for seafood. So I think salmon will not fare well in that competition over the long run. That's one of the reasons why it's so small today, compared with carp production in China. Salmon production is probably not more than one million tons today. Most of it is produced in Norway, Scotland, Canada, and Chile. Carp production is maybe 15 times that or so, and growing at least as fast.

Who's economically benefiting from an export crop like shrimp aquaculture? Does the "trickle down" theory really work?

It depends a lot on the type of fish farming. If you look at salmon production, it's concentrated in the hands of a few companies. The same companies that have salmon farms in Norway have salmon farms in Chile, for example. Carp and catfish production are much more widely distributed. Local farmers in the Mississippi Delta converted their rice paddies into catfish ponds. In China, thousands and thousands of local farmers are producing on a relatively small scale. Where you have good land distribution, as in China, where the average size farm is only an acre and a half, then you have widely distributed production facilities. But it's not working when you destroy mangrove forests and large areas of coast on a commercial basis, like companies usually do. It depends a lot on the type of fish farming. Some is broadly distributed, many people benefit from it, and in others it's much more concentrated.

Who is most affected by the environmental consequences of aquaculture, and how?

One of the great weaknesses of our modern market economy is that the market often does not tell the ecological truth. If a company in Thailand destroys the mangrove forests, put you in the coastal zone between the oceans and the land, they play an important buffer role. If a company simply clears those because it wants to do shrimp farming, then the people in those communities will pay because there won't be anything to prevent the storm surges. When there's a hurricane or a typhoon, as they are typically called in Asia, it can destroy a lot of villages and inundate farmland with saltwater and so forth. The companies will not pay for the damage; the individuals will have to do that. It's a bit like the heat wave in Europe in August of 2003. According to our latest numbers 34,000 people died. Who's responsible for that? The answer is that everyone is responsible to some degree, but particularly those who are primarily responsible for CO2 emissions that are raising atmospheric CO2 concentrations and therefore the earth's temperature.

Our market economy worked reasonably well when there weren't very many of us and the scale of economic activity was small. For example, at the beginning of the last century, a century ago, world population was something like one and one-half billion, maybe even less. The economy was only one-sixteenth of what it is today. So we didn't do that much damage, but with this enormous growth in human numbers and the expansion in the economy, suddenly we're pushing against limits everywhere. The market does not respect limits of fisheries. If you look at the fish market and notice when the fishery starts to collapse, the prices go higher and higher. The fishermen work harder and harder to catch whatever's left. It almost insures in the absolute intervention that the fishery will collapse and many have. We have to figure out how to deal with this; it may mean establishing a quota for fisheries, and then auctioning off those quotas.

To get a permit to catch 20,000 tons of fish a year without going beyond that, that's one way of doing it. But the key is to get the market to tell the ecological truth. I remember Exxon's vice president for Norway in the North Sea said that socialism collapsed because it did not allow the market to tell the economic truth. Capitalism may collapse because it does not allow the market to tell the ecological truth. He distilled a lot of wisdom into that very short statement. Our problem today is that with fisheries or climate change, we're not taking into account the environmental consequences. Deforestation is a perfect example. Consider China in the summer of 1998, record flooding in the Yangtze River Basin went on for several weeks and eventually did 30 million dollars worth of damage. That's equal to the annual wheat and rice harvest of China. It was huge. The government kept saying, "Oh this is an act of nature" and so forth. But finally in mid-August they held a press conference, and they said, "We now realize there's a human contribution to this, in the form of deforestation."

At that point 85% of the original tree cover in the Yangtze River Basin was gone. So they banned tree cutting in the Yangtze River Basin, which was home to 400 million people. Then they supported it with an interesting bit of economics. They said, "Trees standing are worth three times as much as trees cut." And the point was that the flood control services provided by forests are far more valuable than the lumber in those forests. That was a major conceptual breakthrough, but that's the kind of breakthrough we have to make with oceanic fisheries and fish farming. We have to get all the costs on the table and incorporate it into the price of the product. Otherwise we delude ourselves. We have an accounting system, the market, which is not very good at taking environmental issues into consideration. We have an accounting system that's even more flawed than that of Enron. We have a lot of costs that are being shifted to offshore sources, so to speak, and we're not taking them into account, at our own peril.

What kind of aquaculture can take pressure off the oceans and provide food security?

In many ways China is the model for aquaculture in the future, not that everything it's doing is right, but it's doing a lot of things pretty well. Beginning a century ago, when population built up in Japan, the Japanese turned to oceanic fisheries for much of their animal protein. They used the small land area to grow rice, and then they caught fish. They evolved the fish and rice style. Today Japan consumes 10 million tons of seafood a year. Now, if China was to move in the same direction. It would need 10 times as much seafood as Japan, because China has 10 times as many people. But 100 million tons of seafood would be the oceanic fish catch. So China cannot go that route.

Instead they have concentrated heavily on fish farming. The big one is carp production with a poly-culture system, which is ecologically much more sophisticated than any other system in the world. They've been doing it for a long time so they've evolved this system. When the need for dramatic expansion in seafood production evolved, they were ready for it. The salmon farming or the shrimp farming are both historically very recent, and I don't think we've had a chance yet to sort things out. We've kind of hit them rapidly on a fairly large scale compared with the natural production of both salmon and shrimp. We find ourselves in a lot of trouble.

The world market takes no notice of the environmental toll that oceanic fishing has on it. What is the solution to this problem?

What we need is to incorporate all the costs of fish farming in the price of the fish we produce. Whether it's finfish or shellfish or shrimp or what have you. We're not doing that now. A lot of the environmental consequences of fish farming are being born by people other than the fish farmers. But that's not going to be viable over the long term. People are simply going to resist it too much and with good reason. The key is to incorporate these costs. Maybe with salmon production, one ought to have a waste discharge cost for example, so that if the waste builds up in an area at least there would be a cost associated with it and the fee would discourage the discharging. It would affect the distribution of the industry. It would be much more widely distributed in order to fit more easily into the natural system.

Can consumers, and their buying needs, be a part of the fish farming solution?

Yes, with certification. If it's honest and reliable certification, then you have a potential of giving to those who are environmentally conscious and sensitive, a way of expressing that sensitivity. There have been a number of oceanic fisheries, for example, that have been certified, because they have sustainable management. They're very careful not to exceed the sustainable wield of the fishery and so forth. We need much more of that. We may need it as much in fish farming as we do in oceanic fisheries. It is a way of establishing a criterion for producing farmed fish of various kinds that are environmentally sound. We do not now have that. One could achieve these goals through regulation, but regulation is a crude and heavy instrument in many ways. We could use market incentives like certification. It's an economic incentive to produce in an environmentally responsible way. I think it's a strong move in the right direction.

Are submerged net cages (implemented recently by the National Marine Fishery Service) a good investment for large companies/corporations, like The World Bank?

It's a little difficult without knowing more of the details of what kind of fish would be farmed and what sort of feed they would be consuming. But if they're mostly predatory fish there may be some limits on how far we could go. One of the interesting things that is happening with salmon farming now is they're actively trying to breed salmon that will be not predators but that will be able to subsist largely on a vegetarian diet. Whether that will work or not, and whether what you end up with something that will resemble salmon remains to be seen. But there's clearly an effort to move in that direction, because of the recognition that there are limits on the amount of fishmeal that will be available for feeding over the long term. My guess is that we will figure out ways of doing things.

Oyster culture seems to be working quite well in most of the world. Carp production and catfish production are doing well. The offshore ones like salmon and shrimp have not worked that well. They've created quite a few problems. Some of which have not yet been solved. How we move offshore remains to be seen. It's probably going to take quite a bit of sorting out before we eventually get it right. Sometimes economic forces lead us to adjust our diets. Sometimes breeding can improve the quality of farmed fish. For example, in this country, people who live in the South and the Mississippi Delta Region in particular consume catfish locally. But it was not a widely consumed fish 30 years ago. Today it's consumed throughout the country. The breeding of the fish has improved the culinary quality of the fish. The ways of preparing it have now evolved in several different directions. So I find myself often ordering catfish because I find it a tasty fish. That might not have been true 30 years ago when it came from the bottom of the Mississippi River. It might have had a muddy flavor. That's all gone now, so I find carp quite edible.

Anything you want to add?

I'd like to mention a little bit about water, since it's important in fish farming. Just to give you a sense of the importance of water, it is known that we drink typically about four liters of water a day. The water required to produce the food we eat each day is 2000 liters, 500 times as much. Now, the "we" I've been using is the global average. But for Americans, the water required to produce the food we eat is probably more like 5000 liters a day. Five tons of water per day is needed to produce the food we eat each day. It's enormous. I don't think we've fully grasped that yet. Most people sort of accept the idea that we're facing water shortages. If we're facing water shortages, we're facing food shortages.

So 70% of all the water that we pump from underground or divert from rivers is used for irrigation. Water scarcity is now for the first time crossing national boundaries via the international grain chain because it takes 1000 tons of water to produce 1 ton of grain. Countries that are facing water shortages import grain instead of water, because it's so much more efficient to import the grain. So they use whatever water they have for cities and so forth and import the grain. Countries are using grain to balance their water books. Trading in grain futures now is, in a sense, trading in water futures.