Victor Restrepo is the Head Scientist from the International Commission for the Conservation of Atlantic Tuna in Madrid, Spain.


Can you describe the general state of the blue fin tuna population in the North Atlantic and the Mediterranean and make some reference to the changes they have been through in the last 20 years?

Yes. We currently assess two stocks that are managed separately. One is the Western Atlantic, which is roughly the area west of Iceland. The other one is in the extreme Atlantic, which includes the Mediterranean. The Western stock was assessed and is considered to be over-fished. It has been in a very depleted state for the last 20 years or so. It is now managed under a very aggressive program with a very low catch that was assigned to the members of the Commission. The Eastern stock is assessed to be exploited at a higher rate than would be sustainable over the long term but it is not assessed to be in a depleted state, like the Western stock.

Is the East stock the one that spawns in the Mediterranean?


Are the blue fin tuna in danger of commercial extinction?

That is difficult to say that that will be the case for blue fin tuna because it is a species that gets a very high price in the market, especially in the Japanese market. When a species gets such a high price, there will always be techniques developed to improve its ability to be caught, commercially. I'm not sure that will be the case for all fishermen. It will be the case for some fishermen if the current fishing pressure continues to increase.

What is the importance of the Mediterranean to the North Atlantic blue fin tuna population, and the Eastern population?

It's the area where all blue fin tuna are known to spawn. The Mediterranean is very important to the North Atlantic tuna stock, especially the Eastern stock because the Mediterranean is the area, the only known spawning area, of this stock. It's also important for the Western stock because there is a lot of mixing between these two populations that is known to occur. What happens in our end of the ocean is not completely independent of what happens in the other.

Have international treaties like ICAT been successful or unsuccessful in conserving the blue fin tuna stocks?

I am not sure they have been unsuccessful. I am not sure what the situation would have been like if there had been no conventions. This mechanism, with a highly migratory species, is the only one that can get the scientists to collaborate together, to put the databases together necessary to conduct the assessments. It's the only mechanism that can get the politicians to agree on what should be the shares for the different countries. Without conventions like this, without bodies like this, the situation would doubtlessly be much worse, if you think that the current state is disastrous.

Have the quotas been observed? If the quotas have been set, why are the stocks declining?

Generally this is the case for most fisheries in the world, when they are set; it's usually because the stocks are already quite depleted. Very few fisheries are managed with quotas from the start. So I'm not sure that one is a prerequisite of the other.

To what degree has over-fishing in the Mediterranean been a factor in putting pressure on blue fin tuna? If it's an important area for spawning, is there a correlation there?

The fishing in the Mediterranean has existed for over two thousand years, and very high levels of fishing have been in existence for the last four hundred years or so. The current assessment of the Mediterranean and Eastern stock does not indicate that the population has declined tremendously. Between 1970 and now there are almost undetectable changes, given what we have in terms of data. There are criticisms with the data and there are great uncertainties about the quality of this data.

The scientists are very uncertain about the assessment but nevertheless, given the data that we have, there is no demise of the Eastern Atlantic stock. We believe the current landings, the catches of the Mediterranean blue fin, are too high, especially on a small fish to be sustainable in the long-term. What the scientists are predicting is that this stock will be in trouble sometime in the future. When you talk to people like Carl about the demise of the Blue Fin stock, that talk is usually focused on the Western Atlantic, not the Eastern.

Critics of blue fin tuna farming are concerned that the capture of blue fin tuna by French fishing vessels is less regulated than the other fisheries. Maybe it's not passing through the market the way it's supposed to, or the landings are not reported, I'm not sure. Do you know something about that?

I have heard criticism about this, in general. Nothing can be attributed to any one particular country. What scientists are concerned about is the data. The quality of the data that ICAT obtains, ultimately for stock assessments, has been deteriorated. Now instead of the landing fish going through a port where it can be sampled, the fish are measured, weighted, sampled and the live fish go directly to agricultural operations where they cannot be easily monitored or sampled. There has been a large deterioration in the data set. This is not attributable to one particular country; there are several countries that fish with purse seining in the Mediterranean.

What about vessels fishing outside ICAT, with flags of convenience? To what degree is this still a problem in the Mediterranean?

The problem of vessels flying flags of convenience, which carry out illegal or unreported and unrelated fishing, is a worldwide problem. Especially because these vehicles have very large mobility, and they can change names, and licenses and flags very, very quickly. They can move from one ocean to the other very quickly and they can be a problem in the Mediterranean, one day, and a problem in the Indian Ocean another.

Some tuna farmers have suggested that the higher prices they pay for live tuna helps to eliminate over-fishing because fishermen are fishing for dollars not for tuna. The fishermen are then able to make more money. Therefore they are not out chasing after the stocks indefinitely to make their money. What do you think?

I am not prepared to comment on the question of the economics of aquaculture operations or even wild capture fisheries operations because that is really a nonscientific subject. As far as ICAT is concerned, what is managed is the quantity of fish in tons that is caught live from the ocean. What happens to these fish afterwards or who catches them, it's sometimes a concern of the national members, the countries that are members of ICAT, but it is not a concern of the organization itself.

To what degree do subsidies, either with the aquaculture or with vessels fishing wild stocks, affect industries?

The question of subsidies is also a question that is not related directly to the ICAT as a whole. However, if there are recommendations to reduce the pressure, the fishing pressure on a given stock, subsidies that help increase fishing effort would be against the philosophy of such recommendations, in an indirect way.

Will the capture of prey species for the farms, like Anchovy and Sardines in the Mediterranean, deprive wild stocks of blue fin tuna, the food they need? Will there be problems with the growth of this aquaculture industry in terms of the ability of the Eastern populations to rebound or maintain their numbers?

It is difficult to say whether the use of bait fish, essentially to feed Blue Fin in aquaculture operations would have an effect either on the ecosystem or on the Blue Fin tuna stock. First of all, we need quantitative assessment to see what the status of those populations is of fish. I do not know that such assessments have been made. What one could suppose is that any take of any fish could have some impact on the ecosystem but its difficult to say at what level this impact will be. Nevertheless some people are worried that there is a lot of pressure to catch large quantities of small fish, not only in the Mediterranean but in other areas as well, like in the Atlantic. That is a concern, but it is difficult to jump to any conclusions that would be backed up by any quantitative science.

If studies are not being done, or that is outside of the purview of what ICAT does, is anyone looking into this? Is there any scientific body that can look into this, like the European Union fishery folks?

There are international commissioners that need to assess or have in their mandate the assessment of different kinds of species. In the Mediterranean, it's the General Fisheries Commission for the Mediterranean, which has only started fairly recently to conduct assessments for the stocks that move between national boundaries. However many of these species you have been referring to are coastal in nature in which case it would be the responsibilities of the countries to assess and manage them. How they allocate the use of those resources would be, in many cases, the decision of the national governments. Whether those resources would be left to feed wild tuna, to feed tuna in aquacultural operations, to make pellet food for other types of hatcheries, or to feed ducks would be a societal problem for those countries to assess.

Some of the farmers we spoke with feel their best hope is to grow the small fish and release them back out into the Mediterranean to repopulate the declining wild populations. What do you think of this?

The question of feeding wild stocks with hatchery grown larvae is an idea that has been around in marine biology for many, many years and it sounds very nice theoretically. I am not sure of any experience in the world where this has worked well, except in rivers of course. In the ocean, many of these animals are subject to extremely high natural mortality variations. So even though this would be theoretically possible, the costs, with the current know how that we have today, are just too high.

What percentage of Blue Fin Tuna on the world market is farm-raised?

I don't know, I'd rather not comment.

Any other comments you'd like to make Victor, regarding blue fin tuna? Any hopes you might have that aquaculture can, one day, help take pressure off of their over exploited populations?

There is a lot of concern with the exploitation of blue fin tuna as a whole. A lot of focus has been placed now on aquaculture because they have been growing very rapidly and they have been replacing some of the other practices. The value concern is not to look so much at how the fish are being taken but rather how many fish are taken and whether that catch is sustainable or not. Whether the fish are going to go to a sushi-like market or whether they are going to be camped or used for fuel or whatever use they might get, the question is how much are the wild stocks receiving pressure that are not sustainable in the long term.

That should be the real focus. There is too much hope in the notion that some day in the future of aquacultural operations, when they are closed systems and produce larvae, will take pressure off fishing of blue fin tuna stocks. We shouldn't lose track of the fact that right now the catches are too high for the different stocks. We shouldn't place too much of this hope on future operations, we should be concerned about the current state of the fisheries. Fishery resources are societal concerns and how the fish are used are not necessarily a concern of only one particular organization, it's a societal issue.

What do you mean by that?

The allocation of fishery resources can sometimes be a very political issue, and right now the aquacultural operations have been growing very rapidly; it's almost like a gold rush. They are very successful. Of course, when one group of users is very successful, it may happen at the expense of the success of another group. Ultimately the allocation of which group or subgroup is going to be successful or not is a societal issue. It's something that politicians have to face and it's a very tough job to decide who gets to use the resource.