Anne Kapuscinski is a professor of Fisheries and Conservation biology at the University of Minnesota and an Extension Specialist in Aquaculture and Biotechnology with the Minnesota Sea Grant Program.


What might be one of the main reasons why an organic or more sustainable approach to aquaculture is needed now?

It's needed because aquaculture is growing, but unfortunately a lot of the growth involves environmentally unsound ways of growing fish and shrimp and other organisms, and we need a way to redirect aquaculture towards environmentally sound production.

And organic certification, particular, is a good way to do that because it provides a very strong, positive incentive for the fish farmers. That incentive is that they can get a premium price for their product if it meets the standards of organic certification and gets certified.

And there's a growing demand for organic foods. For example, this year the organic market in the US was worth 7.8 billion dollars, and that was a 20% increase over last year and it's been increasing at about 20 - 25% over the last 4 years.

Do you think there's a connection or similarity between the demand for organic produce and organic aquaculture?

Those of us that are working to place organic aquaculture standards feel that there is a similarity. The proof will be in the pudding. At present, most consumers don't know very much about seafood. They don't know very much about where it comes from, how it's produced, so there will be a need for some education.

But one very positive sign is that there is an increased consumer demand for organically certified meats, like chicken, and even beef and pork, so it's not that big a jump from that to wanting to have organically certified fish. So there is a strong parallel.

Do you think by demanding organically certified seafood consumers can help the marine environment?

There's sort of two ways you can get more environmentally responsible ways of getting seafood to the dinner plate. One is by the pull that consumer demand gives. And so if you had increasing numbers of consumers saying at the market, well I want to buy organically certified fish, that is a pull that will be felt all the way back to the farmer's fish pond.

That is a very positive and influential way that a consumer can have direct impact and we've seen that impact with terrestrial agriculture and it's been huge, so there is no reason why we can't have that same positive impact for having environmentally responsible forms of aquaculture and therefore seafood production.

The other way you can try to get to more environmentally responsible methods of production is the push, which comes more from government regulations. You know, essentially having fines; regulations that you have to comply with and if you don't comply with them you're in big trouble.

Pushes are also important but I think one of the things we've learned watching the growth of organic foods is that the pull can often be greater and have a bigger impact than just relying on the pushes.

Is there another reason why it's important to start coming up with some criteria for sustainable or organic approach to aquaculture?

Really the main reason that we have organic standards is to have more environmentally responsible forms of agriculture. There's been sort of a secondary desire, but the standards themselves don't directly address it, and that secondary desire is to make it easier for smaller scale producers and maybe mid-sized farmers to be able to survive financially.

The notion is that if you are producing, in our case fish, at a lower total volume and raising them at lower densities, that makes it hard for you to compete with a big industrial fish farm. But if you're doing that in a way that complies with organic standards and now you can sell your fish for a higher premium, you're in better competitive position.

But the standards themselves don't directly address that; it's more of a happy side effect. So I think a lot of us who are excited about organic certification for aquaculture hope that that will be one of the benefits.

What would be one of the first criteria for organic aquaculture?

Probably one of the first ones would be the fact that the use of antibiotics would be banned. That's already been established in the official regulations that were just approved by the US Department of Agriculture for organic livestock and they were just focusing on animals raised on land, but it's well understood that the same criteria is going to apply to animals raised in the water.

The banning of antibiotics will mean that an organic fish farmer will have to place first and foremost having really good conditions in his fishponds or his tanks, so that the animals have got the optimum rearing environments. So essentially it's taking a preventive approach to healthcare; you don't wait until a problem occurs and then try to fix it with antibiotics. You try to take optimum care of your animals from the outset.

One of the other consequences will probably be that it'll be much harder to raise your fish at very high densities. Maybe some people will get away with somewhat high densities but then they're going to have to have impeccably clean water and really excellent hygiene conditions in order to prevent the disease outbreak.

I should add that in some kinds of aquaculture they don't use antibiotics a lot, but it varies. In some of the big, industrial salmon farms there have been complaints about them relying too heavily on antibiotics. The last few years they've tried really hard to reduce their use of antibiotics, but when a problem occurs they still turn to antibiotics in order to save their production stock. And an organic fish farmer will not have that crutch.

What are the dangers of using antibiotics?

There are really two issues. The first one is looking out for the welfare of the animals. You often end up having to depend more on antibiotics when you're raising animals at very high densities, in intensive confinement. And that raises a lot of concerns about animal welfare and whether the animals are really leading a decent life. Although they're grown ultimately to be harvested for human food, I think there's a general agreement in our society that you should maintain good animal welfare conditions during their lives.

The other main concern is that we are seeing growing signs of antibiotic resistance in bacteria that do cause diseases for humans and for animals. And so the concern is that if we keep indiscriminately using antibiotics a lot, we're just exacerbating this problem of the evolution of antibiotic resistance. And then we end up on a treadmill where you end up then with more virulent or more pathogenic bacteria and then you have to find some way to control those.

So the basic concern is that you'll just make it harder for the fish farmer to be able to prevent a diseases outbreak and some bacteria that infect fish out in the natural environment could exchange their antibiotic-resistance genes with some of the bacteria that might infect humans.

I think we don't know much about how frequently that might occur, but there's a general understanding that different bacteria in nature, if they're found in the same soil or they end up in the same water supply, they can actually transfer their antibiotic-resistance factors, and in fact that's how antibiotic resistance has spread so quickly around the world.

So both animal health and human health experts around the world now are really clamoring for the fact that we need to find ways to reduce our reliance on antibiotics. Because if we end up with antibiotic-resistant bacteria everywhere, then when we really need them, when somebody's really, really sick you're not going to be able to rely on them.

It sounds like the use of antibiotics in an aquatic environment potentially has more risks than it being used on say a poultry farm?

If you're talking about risk to the ecosystem, one of the problems we have is that we have very little understanding of the ecology of microorganisms in the marine environment, or even in freshwater environments. We know that there's got to be a huge diversity of species of bacteria and they themselves are important for the food chain and for maintaining the well being of the freshwater or marine ecosystems. But we don't know a lot about which ones really matter, and if you were to lose them, would that sort of be like removing a building block from that ecosystem and make it harder for that ecosystem to thrive?

For example in the salmon cages, if antibiotics that are in the uneaten food or excreted in the feces of the fish end up in the bottom of the bay, and that encourages the evolution of resistant strains of bacteria in the bottom of that bay, what we don't know is how is that going to affect the biodiversity of those marine bacteria and could it reduce that biodiversity and could that then actually hurt the ability of that entire bay ecosystem to stay healthy?

What strikes you as the next most important criteria for organic aquaculture?

The second one is still under great debate, but it's clearly going to be one of the biggest issues. And that is the use of fishmeal and fish oil in diets that would be fed to some of your aquaculture species. Now this will not be an issue if you're farming oysters or clams and you're going to get organic certification because you don't feed them formulated, artificial diets.

But the typical way of raising shrimp now, for example, is to use man-made fish food that's in these pellets and they usually have, as their main protein ingredient, fishmeal. And they usually add fish oil, partly to provide an energy source for the fish, but also in the case of salmon, for example, it contributes to the salmon having the taste that's typical for salmon because in nature they're feeding on fish.

So for organic aquaculture there's a pretty big debate going on right now. But I think it's going to be I think one of two options. One will be that no fishmeal and fish oil will be allowed at all for organic certification. That will create a lot of conflict because that'll mean that many types of fish aquaculture that are occurring right now will just not be able to get organic certification.

The other option, which is the one that I'm more in favor of, is that you would allow the use of fishmeal and fish oil but only if they come from sources that you can clearly certify are sustainable fishing. And in addition to that, you would try to encourage a reduction of dependence on fishmeal and fish oil.

There's a lot of progress that's happened in fish nutrition research that suggests that you could greatly reduce the amount of fishmeal and fish oil. Some people say you can even get rid of it completely. That might raise other environmental concerns, but at least in terms of reducing the dependence on marine fisheries, which in many cases are overfished, that would be desirable.

Personally, I think it should be compatible with organic standards to allow the use of some fishmeal and fish oil if you can clearly certify that it came from a sustainable fishery and the certification criteria for that are really rigorous and set a high bar.

What's the problem of using fishmeal and fish oil?

The main concern that's been raised about using of fishmeal and fish oil is that many of them come from captured fisheries that are themselves overfished.

So on the one hand, proponents of aquaculture have been saying aquaculture is a way that we can reduce the dependence on the world's marine fisheries and it should therefore be part of the solution. But then critics have pointed out, with some data to back them up, that often the fishmeal and the fish oil that's going into the aquaculture diets are coming from captured fisheries and those captured fisheries are not always managed sustainably.

So that's why I take the position that you don't necessarily have to throw the baby out with the bathwater; you don't have to say absolutely no input from marine fisheries, but it does make sense to say the inputs can only be there if they come from a sustainable fishery. And in fact that might actually be another way to have that positive pull, to actually encourage more sustainable forms of fishing.

And sustainable level of fishing is good in a number of ways, one of which is that it can also create some jobs for the local people that are involved in that fishery. But everybody in the end loses if it ends up being overfishing.

One of the complaints I've heard about aquaculture is the conversion factor. I've heard that it takes 4 pounds of fish to create one pound of farmed salmon.

It's just a fact of life that any animal that feeds higher on the food chain is going to convert the food it feeds at a lower efficiency. So if you went fishing and you caught a salmon, to be able to eat the flesh of that salmon you're benefiting from the fact that that salmon on its own was catching other fish, and when it caught those other fish and ate them it also had a conversion factor. That means that you ended up with less protein in the salmon than when you started with in the fish that that salmon ate. That's just a law of nature.

And it's also true for you and me. We also don't efficiently convert all the protein that we take in; a certain amount of it goes out in waste. So there's no way to get totally rid of that, unless you are going to only be a vegetarian and there are some people who've decided that's what they want to do. If you're going to eat fish that feed naturally on fish, I think you just have to accept that.

But then the trick becomes can you do things to reduce the inefficiency of the conversion? And maybe what we should be asking is, are you raising those fish in a way that overall is environmentally responsible? If you are using some fish protein as input, are you making sure that's done in a way that doesn't hurt the population from which you're harvesting it, and is also done in a way that doesn't actually displace the access of local people to that fish?

There are some cases where the fish that are being harvested to produce fishmeal themselves are a protein source for local people. Now that doesn't make a lot of sense if we're concerned about trying to maintain adequate protein for the world's growing population. Clearly if there's a fish species, like mackerel, that local people can catch and eat directly, we should be encouraging that rather than discouraging it.

But it might be that you can get your fishmeal from a different source. For example, there's a menhaden fishery in the Gulf of Mexico, and menhaden are fish that most people don't want to eat. They're very really oily, watery, bony; they've never really been something eaten by people. If we can have a sustainable fishery of those menhaden without leading to the decline of those menhaden, without hurting that marine ecosystem, I guess I would argue that that's okay.

Is there one more factor that needs to be addressed?

Another criteria that will be very important for achieving organic certification for an aquaculture operation will be assuring that the effluents from your organic aquaculture operation do not pollute the environment. That involves a number of complicated issues.

One of the big ones is to make sure your effluents don't have an excessive load of nutrients in the water that could lead to blooms of harmful algae and other kinds of undesirable changes in the river or in the bay ecosystem where the effluents are going out.

There's also concern about making sure you don't have exotic species escaping from your fish farm, and people don't always think of that as a form pf pollution, and but you can think of it that way. There's going to be concern about making sure that you don't have pathogens leaving your effluent because you've mismanaged the health of your animals.

The questions that nutrient pollution brings up are things such as: have you elevated the level of phosphorous and the nitrogen compounds in your water and have you greatly decreased the dissolved oxygen so that your effluents then end up changing the ability of wild organisms to survive in the bay or in the river that's receiving your effluent?

So this is an issue that the aquaculture industry has been criticized for quite a while and there are many efforts under way to clean up their effluents. Basically, organic aquaculture standards will just set a very high bar for that and organic producers are going to have to show beyond the shadow of a doubt that they're not polluting with their effluents.

Is discharging of effluents a problem for commercial mariculture?

Yes, effluents from aquaculture operations, especially from the high-intensity, large-scale operations have been a problem for aquaculture. They have included everything from excessive feces and uneaten food causing a kind of blanket of particulate matter at the bottom of the bay, to effluents from sort of end-of-the-pipe kinds of operations where they are on land but you've got the effluent then going out into a bay, being too low in dissolved oxygen or the phosphorous levels being too high.

There's been a big concern with shrimp farms, where they've had huge viral outbreaks, that you'll end up essentially spewing millions upon millions of virus particles into the bays. And we don't have a good sense of how able the wild organisms are to fight that off.

To what extent has disease, such as viruses, been a problem to the industry itself?

Disease has been a growing problem for the viability of the aquaculture industry itself. Probably the most graphic example is outbreak of viruses in shrimp farms. We don't have ways of directly treating virus diseases. Viruses don't respond to antibiotics. And about the only thing you can do about viruses is to develop a vaccine against them. Vaccines are very difficult and expensive to develop, and as far as I know we don't have a commercially available vaccine for any of the shrimp viruses today, even though there's a lot of research under way to try to develop them.

So when the shrimp farms get these huge virus outbreaks, they end up with no choice but to abandon the shrimp ponds that they have, and I know this is a problem in many parts of the world personally.

I've seen places in Thailand where they had to just abandon huge expanses of multiple shrimp ponds because they couldn't get rid of the virus, and the only thing they could do is to leave. And this has been compared to slash-and-burn agriculture and it's not good for the shrimp farmers themselves. It's a huge loss of capital and it can eventually bring down the industry in totality.

Just from the consumers' point to view, is there any danger to consuming these fish products with diseases or with antibiotics?

My understanding is that there isn't a direct danger. Most of the fish diseases -- meaning the bacteria or the viruses -- are not also pathogenic to humans. You really should ask a good fish microbiologist because there's there might be a few exceptions to that. And in terms of antibiotics, again, antibiotic residue in the actual flesh of the fish you're eating probably are not going to be very high.

I think eating antibiotics itself won't make you sick. The concern is more this indirect problem that if you end up with a lot of antibiotics floating around in the environment, you encourage the evolution of antibiotic-resistant bacteria and that could come back to haunt you later. But I don't think it's going to directly hurt the health of consumers.

Is there anything else that we should cover?

The fourth criterion that will probably end up in organic aquaculture standards (because they already have been cemented into the regulations for terrestrial organic agriculture) is that you will not be able to raise genetically engineered organisms and have them certified as an organic aquaculture product. There was a clear signal from consumers throughout the nation that they did not want genetically engineered organisms to be able to fit under organic certification.

There have been a draft proposed organic standards issued by the US Secretary of Agriculture about three years ago, and the law requires that they undergo public review. And the Department of Agriculture received about 250,000 individual comments and one of their main message was: we don't want genetically engineered organisms to be certified as organic; we want organic foods to be a clear choice of a different option.

So the Secretary of Agriculture ended up agreeing this is what the consumers wanted and that you have to meet the consumers' demand and so genetically engineered organisms are not allowed under organic certification, and I'm quite sure that the same would be true for aquaculture.

What would be your definition of sustainable aquaculture?

Sustainable aquaculture is environmentally sound, especially for the local environment, it's economically viable for the producer, and it's socially just, for both the people involved in the aquaculture operation and the people in the communities that would be directly affected by the aquaculture operation.

And when you speak of sustainability, do you mean long-term?

The first part of it, environmentally sound, means that you want to be able to sustain the health of the ecosystems that your aquaculture operation depends upon. And so that actually means both the local ecosystem that might be receiving your effluent or that your getting your water from that you need for the aquaculture, but it can also mean the more distant ecosystems, for example, where the fishmeal is harvested from.

The financial or economic viability is also a question of sustaining over the long-term. If you're a producer you want to have an aquaculture operation that you know you'll be able to make a profit from throughout your productive lifetime, and ideally that you could pass it on to your children or you could sell it to somebody else. You don't want the situation that's happened with some of these shrimp farms where you have to abandon the operation in about 5 years. That's not economically sustainable.

And then, be socially just. For example, on the coast of India, large-scale shrimp farms moved in and displaced smaller-scale agriculture systems where farmers for centuries had been rotating rice cultivation with small-scale shrimp farming. That led to all kinds of political and social upheavals. People's homes were being burned down, etc. on purpose. The people who wanted to chase out the small farmers were changing the way the water was being managed in the area with little levies so they had salt-water intrusions to the farmers' rice fields.

That kind of really extreme social injustice ends up triggering political instability which then triggers economic instability and that is unsustainable to the social well-being both of that community, and if things get bad enough, for the country as a whole.

So we want to sustain social justice for reasons that are good both for the noble cause of being kind to everyone, but also really for the political and economic stability of the whole community and ripple effects it has on the whole country.

So what are the potential problems consumers may unwittingly be contributing to when they buy a pound of prawns?

A person buying shrimp from their local seafood market might be unknowingly contributing to damage to the environment and to the destruction of the lives of the local people in the area. And if we can get credible and high-quality certification standards in place, such as organic aquaculture certification, that would give consumers a clear choice. They'd be able to clearly pick out the certified seafood and know that when they buy that they're not contributing to damage to the environment.

Many people say that shrimp and salmon farms necessarily need to be intensive operations in order to be profitable for farmers and investors, and that traditional farming techniques, since antiquity, that were not intensive haven't been commercially viable. Is this true?

I think it really depends on what your intended market is and how you're going to define commercial viability. If you want to produce shrimp for a local, domestic market, your transportation costs aren't high, etc., you may easily be able to have a profitable operation in which you're raising shrimp at lower densities.

If you want to go for export markets, that's often when there's the pressure on the company to have an approach where they're going to produce high volume and bring down their per unit cost of production. I think there it's a real challenge, and it may turn out that some of those kinds of operations just would not be able to survive if they had lower densities.

One silver lining might be if you could find ways to mix your production of salmon, for example, with raising some seaweed that are also useful in industrial manufacturing, for example, an ingredient to cosmetics and pharmaceuticals. You can put a habitat, for example, below the salmon net cages and encourage the growing of some shellfish species, some mussels, maybe even some snails that are edible.

So basically if you can diversify the kinds of seafood products that you're producing in your fish farm, you could still maintain a fairly good total yield, but you have a lower density of any one of the species. And one of the basic ecological principles that could be better applied in aquaculture that would lead to more environmentally sound aquaculture is to have a diversity of species.

Because they each use a slightly different kind of food, they fill a different niche in your water column, and they don't all have the vulnerability to the same disease. So diversity can actually make your aquaculture operation both more environmentally sound and also less vulnerable to certain kinds of problems.

Right now in the forms of aquaculture that have really captured consumer attention and the public's attention, like salmon farming and shrimp farming, there's been very little experimentation with diversifying the species. But there is some work starting and I think it holds some promise.

Interestingly, the more traditional forms of aquaculture, such as evolved in China thousands of years ago, one of the basic principles was to be raising more than one species at a time, to have that diversity and be able to benefit from the synergies from that.

Are you saying then that shrimp and salmon cannot be farmed in an intensive manner, with high stocking rates, and still be sustainable?

My instinct is that you won't be able to raise them at as high a density as we have now. But it might turn out that if you seriously apply some of these ecological principles, you could reduce the density but still have it be relatively high.

I'm thinking of an example of the work that I learned is beginning to happen in southern Chile, where there's an aquatic ecologist who's starting to work with the salmon culture industry. And she's trying to find ways to get them to prevent some of their effluent pollution problems, for example, by greatly improving the way they feed the fish, so that they minimize uneaten food leeching out into the surrounding water column.

But she's also experimenting with putting floating pens around the salmon cages where they're raising mussels or other kinds of clams and even algae that essentially will absorb those nutrients. So it may turn out that if you perfect those kinds of approaches that you could still have fairly high densities.

Then a lot of the shrimp, for example, that are exported from large intensive aquaculture operations in places such as Thailand and Ecuador, will never be able to make this organic label?

I think that's right. To be completely honest about it, the mainstream ways of producing shrimp in shrimp farms and mainstream ways of producing salmon in salmon farms will have to change dramatically to be able to meet organic certification. And those two forms of aquaculture are probably the most graphic examples where huge changes will be needed in their practices. That's not to say that some operations won't come up with effective ways of meeting those certification standards, but they're going to have to really change from what they're doing today.

It also opens the door for real innovative farmers who might come up with a different way of raising the shrimp and the salmon, produce a smaller total volume but be able to take advantage of the premium and the growing demand for organic-certified and still have a very viable business and possibly even a more profitable business.

Why is a reliable certification program important when it comes to identifying organic products?

If you're going to have a label on the product that says this is organically certified, consumers need to know that there is consistency in the standards that the operations were required to meet and they need to know that those standards are high. So you need to set a high bar and know its consistency. It's very similar to the Good Housekeeping Seal of Approval. Consumers aren't going to believe in it if it's a moving target and in some places it's a high standard and in other places it's a low standard.

So what is the problem of the industry running its own certification program?

The problem with any industry running an entire program for certifying some kind of an eco-label for its products is that it's going come across to the public as the fox guarding the chicken coop. There isn't a system of checks and balances. Our system of government in the US works that way on checks and balances. And at the end of the day I think it's in the industry's best interest to have it be an independent party that does the certifying. Otherwise what they'll end up doing is undermining the credibility of their own eco-label and they'll just actually lose more consumer confidence.

In establishing criteria for what will be certified as organic farm-raised seafood, why is it important to provide a diversity of producer stakeholders and consumer stakeholders?

It's important to involve a diversity of stakeholders of the producers and the consumers in developing organic standards because from the producer's perspective you've got to make sure that the standards are actually practical, that somebody can actually raise the fish and keep it alive and have some kind of chance to be able to earn a living doing it. If you come up with something that's great in theory but totally impractical, then no producer will try to get organic certification for aquaculture and it will just provide no benefit to all these wonderful environmental goals we have.

You need to involve a diversity of stakeholders from the consumer's perspective because you need to have a good sense of what matters to consumers. And you need to make sure that you are going to meet the demands that consumers have. So it's really a marriage of the two, making sure that they're practical from a producer's perspective and that they're meeting the needs and the desires of a diversity of consumers.

What's the best way to farm salmon, as far as locating the actual enclosures where the fish are raised?

The best way to farm salmon if you want to protect the environment is to minimize the direct contact between the container you're raising the salmon in and the natural environment. So if you can raise them on land, or enclosed systems, you're better off. It's much easier to prevent escapes into the natural environment; you can almost completely eradicate them. You have an end-of-the-pipe effluent so that it becomes easier to treat that effluent and make sure that the final discharge is as clean much as possible.

When you raise them in a cage that is just floating in a bay, you don't have the ability to do that end-of-the-pipe treatment of the effluent, and it's very difficult, if not impossible, to prevent them from escaping.

Is this going to be another case where a premium price must be attached to an organic label in order to make organically farmed products commercially viable, or would they be available on a wider scale?

The current situation is that the corporations that are running the salmon farming industry put all their capital in the existing equipment that they have. And so the way our market economy works, they have really no incentive to switch their capital to new equipment that will be very expensive upfront to put in place -- closed systems or land-based.

It's possible that the premium that you would pay for organically certified salmon would give them some of that incentive. But I think some companies might end up deciding that it's not enough and they either won't try to go for organic certification or eventually they'll go out of business. Definitely it will help the conversion of at least some of those operations.

We've heard some horror stories about diseased salmon that escape from net-pens and then infect wild fish populations. How serious a risk is this and is it the main risk?

I think there are three major problems with salmon escaping from cage-culture fish operations. The first one is actually a genetic pollution problem. If you have salmon escaping into environments where there are wild salmon populations and if they're from the same species, if they can interbreed, they can alter the genetic makeup of the wild populations. And often those wild populations themselves are in decline and in trouble, and altering their genetic makeup could just be the last nail that drives home their ultimate demise.

The second problem in parts of the world where there are not wild salmon populations, such as Chile or Australia and Tasmania, is if you have salmon escaping from the cage-culture operations and establishing viable populations in the natural environment, you've essentially introduced an exotic species and the question is, is that altering the biodiversity of that marine ecosystem and hurting some of those species?

My understanding is that we have not been collecting the data that are really needed to figure out whether they're causing harm or not, but there are a lot of principles of ecology that would suggest that if they establish viable populations and they become a dominant part of the natural ecosystem, they will have probably displaced some local species and then you really need to look hard to ask whether you're destabilizing that ecosystem.

The third problem is the disease one that you've heard about. And again, in many cases we haven't been gathering the data, we haven't been doing the monitoring that we need to be able to get a sense of how often do the farmed fish transfer the disease to the wild fish versus how often did the wild fish harbor it already.

There are some clear cases that have emerged recently that strongly suggest that the farmed fish caused a disease problem for the wild fish. One of the ones that I've heard about is the spread of sea lice from the cage-culture operations in parts of the United Kingdom, in Ireland I think, and finding sea lice on wild runs.

In this case I think it was the brown trout, which in that part of the world are sea run (they go to the sea for part of their life and then they come back into fresh water) and some of them were found infected with sea lice that very, very likely came from the fish farms, where at certain parts of the year the fish are coated with so much sea lice it almost looks like they're wearing a fur coat. Sea lice infestations have been a really big problem.

On the Pacific coast, salmon fish farms are almost exclusively farming Atlantic salmon. What is the problem of Atlantic salmon escaping into Pacific Ocean?

The biggest ecological problem that escaped farmed Atlantic salmon pose on the West Coast to wild salmon is competing directly with steelhead, which is one of the wild salmon species. And steelhead populations are in decline, many have gone extinct; they are in trouble up and down the entire West Coast.

Then what's the problem with farming Pacific salmon?

The main danger there would be that if they have large numbers of escapees and they don't come from the same gene pool as the wild fish, they will be able to directly interbreed with the wild Chinook salmon populations and alter their genetic makeup in such a way that those wild populations won't be as well adapted to the natural environment. And again, wild salmon populations, as almost all species, are in decline and we don't want to add insult to injury.

Their genetic makeup, the current genetic diversities are sort of an insurance policy against further changes in the environment. It maximizes the chances that they'll be able to adapt to their natural environment, and if you have them interbreeding with domesticated lines of fish, you're reducing their ability to remain vigorous and to thrive in their natural environment.

We met some Thai shrimp farmers who believe that intensive shrimp farming is worth the risks posed by disease because they can make 5 to 10 times more money than growing rice. What would you say to them? Do they have hope with this organic label, or is going organic too costly an investment for the small family farmer?

I hope that the small-scale shrimp farmers in Thailand and other parts of the world will be able to benefit from an organic label. They may have to form some sort of marketing cooperative or pool their resources so that they have enough total volume to export. But if they really meet organic certification standards they are going to have a big competitive advantage over the larger scale shrimp farms that essentially have a certain amount of inertia in their business plan. It'd be harder for them maybe to convert their practices and their capital, so it could give the smaller producers an edge.

But I realize that the world of finance is complicated and it might not work out that way for everybody. My guess is that the more entrepreneurial of the small-scale farmers, the ones who want to get in on this early on and are willing to make the real changes in their production, and if they're willing to work with other small-scale producers -- essentially have a kind of marketing cooperative -- I think that they might have a real advantage.

The other thing, though, that I would say to those small-scale farmers today even if organic certification never came into existence is, think of your children, think of the future generation. If you can make a lot of money now but in 10 years you'll be out of business and you've destroyed the productivity of the soils in that farmland to be able to produce something like rice, which is so important to the food security of your country and your community, you will be making the future much, much harder for your children.

What's the main problem in raising genetically modified salmon?

The main threats, if genetically modified salmon escape into the wild environment, is that they can become a new kind of nuisance species, displacing some of the native species that are important to the ecosystem or even to local fishermen. And another threat is that they could trigger extinction of the wild salmon populations through something called the Trojan Gene Effect.

The Trojan Gene Effect occurs when you get genetically modified animals, in this case salmon, that simultaneously have a mating advantage but have a great reduction in the viability of their offspring. So if they mate with wild relatives in the environment, because they have a mating advantage they drive their genetically modified genes into the wild population. But then the result is that those wild fish have lower survival in the natural environment, and over time that causes a dramatic decline and could lead to extinction of wild populations.

Are there any circumstances under which you think GM salmon could be raised in a safe manner, such as in tanks sealed off from the natural environment?

The best way to assure environmental safety if a fish farmer wants to raise genetically modified salmon would be to have multiple barriers in place. One would be to grow them in a closed system or at least in on-land facility so you can have really good mechanical barriers to their physical escape.

But the second thing you should do is to make the fish sterile and there are ways of doing that. And until we know better what kind of ecological behavior these fish will have, you should also require that each fish be screened to assure that it's been made sterile. And I've argued that there are cost-effective ways of doing that.

The industry says that the genetically modified salmon are sterile so that eliminates the danger posed by the escape of GM into the wild.

First of all, genetically modified salmon are not naturally sterile. You have to do an extra step to make them sterile. The methods for making them sterile are easy to apply, but they're not 100% foolproof. So to really assure that all the production fish are sterile I argue that we need to screen each fish before it gets put in the net-cage operations to confirm that it is indeed sterile.

And I figured out that the cost would be minimal, especially when you look at the cost relative to the price you can get for selling a harvested adult salmon. It's going to be something like 2 to 5 cents extra per pound of salmon that's harvested as an adult. And given that we don't know well enough what environmental effects these fish will have, that seems to be a small price to pay at this point to assure that every fish is sterile.

Additionally, there is a precedent for requiring confirmation of sterility of each fish on a large scale. In Florida, the state allows people to introduce an exotic species, grass carp, for weed control in their canals. But they require that each fish be screened to prove that it's sterile. So if they can do it in Florida, we should be able to do it in the salmon farming industry.

Can you address the argument that 95% assured sterility is good enough?

No, I don't think that 95% assured sterility is good enough. When you consider that genetically modified salmon could be raised in many, many fish farms, when you consider the scale of escapes that happen -- we know that storm events can lead to escapes of hundreds of thousands of fish at a time -- when you consider that we don't have direct proof that these fish are environmentally safe, so you put all those things together I don't think 95% sterility is good enough.

Does the industry really want genetically modified salmon?

Well, there have only been a few public pronouncements by industry groups about genetically modified salmon and so far all of them have said very clearly, "We're not interested in raising genetically modified salmon." The Canadian Salmon Farmers Association have said that. I was recently in Chile and a key person leading one of their major salmon farming associations in Chile publicly stated very emphatically that they're not interested in genetically modified salmon.

So whatever public statements out there indicate that salmon farmers are not interested in these fish.

Why not, if they grow faster and bigger?

There's I think a couple of reasons. Right now, there's been a consumer backlash against GM foods. And the salmon industry has a fairly good reputation with consumers. Salmon are considered a high-quality, desirable food and I think they don't want to lose consumer confidence.

But there's a second reason that could turn out to be really more important, and that is that the GM salmon are patented. And when a fish farmer buys these they have to enter into a contract with the company that would sell them the salmon, they have to pay a royalty fee and I heard direct statements in Chile, for example, that Chileans are not comfortable becoming even more economically dependent on outside parties. They would rather develop their own domesticated lines of salmon and do their own breeding programs.

What do you think about efforts to genetically alter salmon or shrimp so that they require less fishmeal in their feed?

The suggestion that you could genetically modify salmon or shrimps so that they will require less fishmeal in their feed strikes me as a classic example of a quick fix that will backfire. First of all, what makes salmon taste like salmon is that there is some fishmeal and fish oil in their diet. If you remove that totally from their diet, they're not going to taste like salmon and consumers might really lose interest in them.

Secondly, we know enough about genetic engineering now to know that very often you end up changing more than one trait. You don't only change the trait you want to change. And some of those other trait changes might not be desirable for the fish farmer, they could cause some ecological problems, and in some cases they might even cause some food safety problems. So you're fixing one problem but you're maybe opening the door for a whole bunch of other problems.

It seems to me it would make a lot more sense to figure out how we can reduce the total percentage of fishmeal and fish oil in the diets, have enough in there so you still get that real salmon flavor and you meet the basic protein needs of the fish, make sure you don't waste the feed that you have good feeding methods, and then make sure that the fishmeal and fish oil come from sustainably-harvested fisheries.

Is there a potential risk to people eating GM salmon?

The kinds of GM salmon that are proposed to be commercialized today probably will not pose a food safety risk to consumers, but that doesn't mean that others in the future might not. You would have to look at it on a case-by-case basis.

David Suzuki, a geneticist, says that the science of genetic altering foods, etc. right now is in its infancy and people have no idea what kinds of problems they might be creating. Would you care to comment about what stage of the science the industry is in?

The state of the technology is paradoxically both a very powerful technology but one where the genetic engineers don't have much control over what they're doing. They cannot control how many copies of a gene get inserted, they can't control where in the animal's chromosomes they get inserted, and it turns out that all those things matter.

So I would agree with the general statement that it's not as precious a technology as people might think it is. Maybe some day, with great improvements in the methodologies you would be able to more directly control exactly what happens when you insert the genes and be able to more directly predict the outcomes.

But right now it is sort of a black box. It's sort of like a kid discovering some new tool but not really knowing what are all the consequences of using that tool in many different circumstances.

Is it a reasonable argument for farming genetically engineered fish if the product would use less fishmeal?

If genetically modified salmon that have been engineered with extra growth hormone genes do indeed require less fishmeal per unit of salmon flesh you produce, that's all well and good but it's not sufficient justification to encourage the salmon industry to switch from normal salmon to GM salmon because those GM salmon raise new sets of environmental problems. So you are partly solving one environmental problem but raising new sets of environmental problems and that's not a net gain for environmental sustainability.

How important to food security is aquaculture now, and do you see it as becoming more important?

I think aquaculture is important for food security in a number of developing countries. China is one of the prime examples, but in many parts of SE Asia and to some extent in Africa, when local small-scale farmers can produce their own fish that gives them food security because they have control over the means of producing their own food.

The fish species that will contribute to their food security are not the ones that are the high-valued, the high-priced ones that can then be exported to developed, rich countries. They're the ones that the local people can afford to eat themselves.

One exception to that is, for example, in India for centuries people were mixing shrimp farming with rice cultivation and it was a much less intensive form of shrimp farming than these big industrial shrimp farms. And at that time the local people could afford to eat the shrimp and that's partly because their whole market structure was different, so that can also contribute to food security.

I think therefore it really depends on where you are looking. What community you're looking at and what aquaculture species you're talking about. It makes absolutely no sense to think that high-priced aquaculture species contribute to food security. It's going to really be more the species that the local people can control, produce themselves, and can afford to eat themselves.

Do you know what percentage of the seafood consumed in the world today is being farm raised?

The percentage of seafood produced in the world today that comes from aquaculture is 20%. That's 1997, 1998 statistics. The Food & Agriculture Organization predicted that it could get as high as 30% of all the seafood produced by the year 2000, but they haven't cranked through the numbers yet for the year 2000. That prediction's important because it shows that the percentage of seafood that is coming from aquaculture is growing rapidly.

A lot of scientists still have hope that marine aquaculture will take the pressure off captured fisheries. What do you think?

I think aquaculture could take the pressure off captured fisheries if it's the right kind of environmentally responsible aquaculture and at the same time we have policies that encourage sustainable fishing. We need both. Aquaculture itself is not a silver bullet.

The bulk of the world's farming of fish happens in China. Are they doing it right?

China is the birthplace of aquaculture, about 4000 years ago. And for most of those many thousand years they had been doing very sustainable forms of aquaculture and we could learn a lot from their dominant, traditional forms of aquaculture.

Unfortunately in the last few years, especially starting about 5 years ago, with the increasing incomes in China and increasing connection to the global economy they have begun to convert some of their extremely sustainable aquaculture systems to more westernized forms of aquaculture where they're raising single species, higher-valued species, but species where they need to put in more formulated feeds, including fishmeal ingredients.

And I'm worried that they might abandon their thousands of years of wisdom and start to go for the glitter of the high-priced, high-valued species that the West desires. And in fact recently I learned that soybean producers from the US, who are desperate to find new markets for their soybeans, are even trying to convince the Chinese to buy soybeans to make more artificial feeds for their aquaculture species.

This would actually be a step backwards because the beauty of the traditional Chinese aquaculture system was it was a poly-culture system where they were raising 3 or more species of fish at the same time, and all relying on natural foods. They had natural blooms of small animals and small algae in the ponds and they could just use inputs and fertilizers that came right from their local farms. And the beauty of that was that they were recycling and reusing all the locally available nutrients.

If you now are going to import soybeans that are produced in the US using high amounts of fossil fuels, really high energy, and soybean farming itself raises some environmental problems, you're now going to export those soybeans to China and put them into the fish food for the fish you're raising in China, you're increasing the energy inputs rather than keeping them minimal, and all the transportation costs, etc. It's a step backwards.

But what has worked positively for China?

Modern-day aquaculture in developed countries could learn a lot from the thousands of years of experience with aquaculture that comes from China. The Chinese had thousands of years to work out a really sophisticated system that is highly productive and environmentally sound.

They produced both a high volume of fish protein per volume of their fishpond, with minimal of inputs and maximizing the recycling of the nutrients and the recycling of energy. So it's really very ecologically sound form of aquaculture. And it was really well integrated with their crop farming and even their pig and their duck farming, so it was a really well integrated system that fits many of the principles of ecology.

What can you say about invertebrates?

One form of aquaculture that has great potential for being environmentally responsible and meeting consumer demand is the farming of invertebrates. This can include mussels, clams, oysters, abalone, and even giant clams. The potential benefits of farming invertebrates is that they don't need to be fed diets that have fishmeal or fish oil in them, they feed very low on the food chain, and you can raise them in fairly small growing areas.