Skip to main content Skip to main content

The Habitable Planet: A Systems Approach to Environmental Science 

Looking Forward: Our Global Experiment Interview with Daniel Pauly

Interviewer: Would you tell us about your research.

DANIEL: I’m the Director of the Fishery Center at the University of British Columbia in Vancouver, Canada. I’m a professor of fisheries and I work on a global scale. Very few people work in fisheries on a global scale; most of them are limited to a bay or fishery in the Gulf or a country at most, but not internationally. Before that I worked in the tropics.

Interviewer: So what got you first interested in science?

DANIEL: I grew up in Europe, specifically in Switzerland, and I studied in Germany. I wanted to study something that would be of use in a developing country setting because I planned to leave Europe and to work presumably in Africa. And I wanted to study a science, which would have practical implication, because at that time in the 60s everybody wanted to help out. And because I couldn’t do physics, I wanted to study biology.

Interviewer: And what got you interested in marine biology?

DANIEL: Really nothing special. I’m very different from a scientist like E.O. Wilson who had a deep affinity to the real organism. I can go through a forest and not see the birds. I’m interested in the ideas that represent the process—that linking co-system. I like the way explanations are found for things that happen in the ocean and things that happen in nature. I enjoy this, and I like to see the patterns. So I work not on the things themselves, I like to see patterns and data that represent processes.

Interviewer: Why is it important to study marine ecosystems on a global scale?

DANIEL: When I decided to work on global fish populations, global fisheries as a global phenomenon, I had been in the Philippines working on tropical fisheries, on single fisheries. I was surprised when I spoke with a colleague and learned that The International Rice Research Institute was working on developing a new variety of rice for planting. The rice people knew very well what the rest of the production in the world was. In other words, they could put their rice in the context of worldwide production. But I could not put the fisheries that I was studying in the context of world fisheries. And I realized that actually very few scientists were working on world fisheries as a topic. With a friend, I started writing a series of little papers on world fisheries and realized many assumptions that I had made about the world catch and the world potential. So I in a sense, created a field of world fisheries as a study object.

Interviewer: You were looking at an ecosystem in one area. What made you move to a more global outlook?

DANIEL: I really zoomed in on the concept that fisheries have sampling devices. For fifty years, fisheries data have been collected by the Food and Agriculture Organization (FAO) of the United Nations in Rome. People fish wherever they can and wherever there is fish for them to catch. And they don’t fish where there are no fish. So by studying what they catch, i.e., the catch data, the catch statistics, you can infer some things about the state of the ocean. I’ve become a specialist in the analysis of this FAO data. Up to the mid ‘90s, the data wasn’t analyzed by scientists; it was just taken as a gospel. I began to analyze the statistics in some detail. The first paper that I wrote was a re-computation of the amount of primary production that was needed to sustain the catch and the world catch, because up to now people were doing the inverse procedure. They were looking at how much primary production there was and then how much potential catch there would be. And this computation I always thought came with a huge amount of uncertainties. So I did the inverse, which is to look at a catch and to infer how much primary production was needed and what fraction it was of the primary production. I published this paper in Nature in 1995, documenting for the first time that we had a huge impact on the sea because at least in the shallow waters around the continent, we were thinking one-third of a primary production was needed to sustain the fisheries.

Interviewer: What are some specific things you’ve learned from your analysis of the FAO data?

DANIEL: We transformed the data into maps. The first result that we looked at was the fact that China was catching much too much. It was impossibly high. We looked at this in depth. And in 2001, we published a paper in Nature that China was over-reporting its catch, they doubled the catch that they legitimately needed to catch. The result of this was that the world fisheries were not increasing in the ‘90s, but decreasing. So we discovered that world fisheries had begun to decrease from the late ‘80s on.

Interviewer: And what did you learn about the Japanese industry?

DANIEL: Again, we used the catch data that the countries sent to FAO and that FAO processes. The second step we did was replace this data in various countries by the data obtained directly from their countries. In other words, in most countries you have the Department of Fisheries collecting data, writing reports. And the Department of Statistics or the Department of the Prime Minister’s Office or the Financial Minister sends the data to FAO in Rome. But there is a loss of information between the Department of Fisheries and the institution that sends the data- that loss of information can be compensated for by reacquiring the data that are available at the country level. You discover that for political reasons or for reasons of convenience that many, many countries don’t report what they catch. We have started a series of investigations on that. It turns out that, for example, the State of Hawaii underreports the catch of its inshore fisheries by a factor of two. But Guam and the Mariana Islands and other islands that are U.S. flag territories underreported by a factor of ten to fifteen. We have found that this is a pattern generally repeated throughout the Pacific, people don’t know that they catch a huge amount of fish in their inshore fisheries.

Interviewer: How far back does the catch data go back?

DANIEL: The catch data that FAO had collected, started in 1950, which was a good time to begin because World War II destroyed lots of fishing capacities in a lot of countries and the boats were used for other purposes. This provided a good baseline. Also, lots of the countries that are now developing were colonies of the European nations in the ‘50s. So the ‘60s and the ‘70s reflect the attempt to free themselves and build new fisheries.

We also know from studies conducted with historical sources, such as expeditions, that there is another reality that goes way back when stocks were completely untouched that my colleague, Jeremy Jackson, addresses. The analysis of this catch data enables a rigorous evaluation of the trend in fisheries. And we must use the old data, contrary to the fashion in most fisheries research, because we need a good baseline. We need to know how it was before it began to be strongly industrialized. This provides a contrast that we can use to see how fisheries are today. If we use only the last ten years, we would not see anything happening.

Interviewer: Can you tell us about the historical expeditions. What do they tell you?

DANIEL: In the sixteenth century, European countries began to systematically send expeditions throughout the world. These expeditions very much represent the equivalent to our sending the space shuttle nowadays. In addition to the captains, you’d put so-called naturalists on the boats. The most famous of them was Darwin. The naturalist was the doctor on board. But he was also the narrator of the expedition and the one who observed what was found and reported it. The expedition then sent back the loot they had acquired to Europe, to the museums, equivalent to bringing home solar dust or rocks from the moon. The scientists of the time, they all gathered to have this information available. Now we can now look back at these reports and we see descriptions of the various countries that are now developing countries. We can see the description, for example, of abundance, abundance of mammals, of birds, of life in general, which we can use and plot. We can plot against time; we can plot the range of certain animals and we can see them declining. Jeremy Jackson has worked on this and a colleague of mine, Maria Palomares, works on this extensively. She records the anecdotes, the observations of animals, and quantifies them where they reflect abundance or rarity. Over time, we see that for a certain group, say, seabirds, you would have their abundance observation diminish and the rarity observation increase. So you’d plot this over time; and so you have a time machine that enables you to quantify by diversity of observation for three hundred years in the past, which we couldn’t do before.

Interviewer: Industrial data, catch data, historical records – is this science?

DANIEL: This certainly is science. It is science to observe and to quantify. It doesn’t matter what the instrument is you use. Many people believe that biology was equivalent to physics where you can turn the direction of the change and it doesn’t matter which way it is analyzed. For example, how the planets turn around the sun. They could turn backward and it would be the same thing. In biology, it matters a lot. Our role of time is only in one direction. For example, it’s extremely hard to recover ecosystems once they have broken. And it’s also extremely hard to recover broken abundances of certain animals. In fact, when a species is gone, you cannot rebuild it.

The processes that generate the observations are different. But you’re trying to infer from processes that are not amenable to the senses directly, you’re trying to infer what happened from points on a graph. And it doesn’t matter whether that is generated by a nuclear reactor, by an accelerator or three hundred years of history.

Interviewer: When you put together all this data, what are the results are?

DANIEL: When you put together the open expeditions plus bridging data that we have in certain countries from 1900 to World War II and the field data from 1950 to now for the world, we have trends that are very strong. These trends are large animals are removed by humans, and small animals are left. For the sea, I call this process fishing down, mining food webs. The most frustrating thing is the animals that we catch are getting smaller and from lower in the food web. On average the catch is now compulsive animals lower down on the food web. So that’s one process. A second process is we are driving many systems toward a state where they only mainly consist of microbes, and jellyfish. My colleague, Jeremy Jackson, calls this the rise of slime. We had a richly structured three-dimensional system and we’re reducing it to two-dimensions. Animals are also getting short-lived. Short-lived animals are low on the food web living in a two-dimensional habitat. The water column altogether is full of murk and is more murky than before. And you have the extension of dead zones. You have a situation where you move from predictability to unpredictability, from healthy ecosystem to unhealthy ecosystem, and from exploitable ecosystems to difficult to explore ecosystems.

Interviewer: Can you put into numbers what’s happened to large fish populations?

DANIEL: I have a colleague who published a few years ago the fate of a large fish, typically tuna or a bottom fish. It takes about ten years to reduce it by eighty percent. In other words, ten years later it will reach eighty percent depletion. So twenty percent would be left. Fifteen years later, ninety percent depletion; ten percent will be left. That depletion curve is the rule, and it happens everywhere you look. It particularly happens with the larger fisheries. There seems to be a tendency, when we throw our industrial might at a fish species, to deplete it in ten to fifteen years. So that’s a given.

So all the management we do is concerned with collapsed fisheries. And collapsed fisheries are actually getting more and more abundant. If you define a collapsed fishery as ten percent of the catch that it had before, then we have now reached about thirty percent globally. The others would be optimally explored. If you project collapsed fisheries into the future, you will have a hundred percent collapse issues in 2048. Now that was published and much criticized because a prediction that precise cannot make sense. But predictions are based on the statement “all things being equal” and things don’t remain equal. Obviously there will be either an acceleration of the trend or a slowing down of the trend. But it does indicate which way we’re going if we don’t do anything. So in 2048, the fisheries will consist only of collapsed fisheries. And let’s not fool ourselves. This is a real danger because right now the fishery catches of the world are decreasing. And they are decreasing because during the ‘70s and ‘80s there were major collapses.

Interviewer What is the current status of the fish population in terms of marine bio-diversity?

DANIEL: We are at the threshold of major extinctions. Many species in the ocean have seen their population decline and eradicated. Populations are in many cases incipient species, separated groups of animals that produce by themselves. A species might consist of, say, ten populations. In many cases, only the most productive, most abundant population is left. All the smaller populations around the central population are gone. And really to extinguish the species, you have to extinguish only its last population. In many cases, we have reached and are exploring that last population. So I would say the fisheries of the world are poised before that last act.

You have to realize that fisheries are heavily subsidized. The subsidization rate is about thirty to thirty-four billion dollars per year. This is double as much as had been estimated by the World Bank. Normally when your old fish population becomes so rare, you should be losing money exploring it. But if you get subsidized, in other words if there is money transferred from the government, from the taxpayer, to you in the form of cheap boats, cheap fuel, cheap advice on where to find the fish and so on, then you can catch the fish even though they are very rare. You can also catch fish that are rare as by-catch of other species. You fish for species A and you catch species B, which is very rare — which is maybe even threatened as in the case of turtles. That’s the reason why fish are threatened, because it’s cheap to fish them and they are not the target of the fishery. They are the by-catch. And when by-catch fishes are caught, people also have the impression this is not a great loss; it’s just a rare species. But rare species is what a species always is before it’s extinct. A species can start out very abundant. It has to become common and less common and rare before it can be extinguished. All species become rare before they are extinguished, even species that are very abundant. Also, a species is extinguished only when you repeatedly cannot find it in its range. But that implies that you’ve sampled it and that you know about a species that you don’t find. That means you must be an expert in recognizing such species so that you know when you haven’t found it. Generally, it takes about forty years before a species is accepted as extinct. So how many species are extinct or almost extinct that we don’t know about?

Interviewer: Given the current trends, what is the worst-case scenario?

DANIEL: The worst-case scenario is called the sixth extinction. Throughout the history of the earth there have been five major extinctions and that defined the transition between different epochs. The best known one is sixty-five million years ago when the dinosaurs were wiped out. Now this was not the biggest of them all. The permian extinction was more important. It wiped out ninety-five percent of all species on earth. I think that in the extinction sixty-five million years ago, only about sixty-five percent of the species were eradicated. Five of the extinctions were natural. Most probably they were due to big meteors hitting the earth and generating such an explosion that you had fires and earthquakes.

Right now there is an extinction. Now this extinction is different. It is over a period of one hundred years. The habitat destruction — fragmentation and destruction, harvesting of birds, harvesting of reefs, overfishing, and global warming if we let it grow the way it looks that we’re going to let it — this intentional and unintentional destruction is going to terminate the job. That extinction could affect lots of species. In fact, some people have estimated how much that would be. At present it is about twenty-five to seventy-five percent of species of plants and similarly for animals. And that depends on what scenario you’re willing to accept as probable about the future. Business as usual certainly would see most animals and plants, especially large animals such as sharks go extinct. It’s almost a philosophical question that says what will happen in twenty years? What will happen in thirty years? Will we be able to maintain this bland belief that we can continue with anything? That I don’t know. But with business as usual, lots of fish will go.

Interviewer: Are there things we can do that will avoid this disaster?

DANIEL: There are things we can do and there are reasons for optimism. Essentially the subsidization rates cannot keep up with the price of fuel. Then the price of fuel really hits hard. And some of the fuel-intensive fisheries operations go bust. So you cannot go fishing, for example, far offshore with your gear if you’re only going to catch a small amount of fish. That is one reason for optimism. Another reason for optimism is the fact that most species are coastal and so each country can do a reasonable job managing its fisheries without affecting the others. That’s not true for tuna, obviously, and large sharks and so on, but some things are regional or local even. But it’s not an optimistic picture if we consider global warming, if we consider acidification. I think we have to bite the bullet and say unless we tackle the issue of global warming head on, unless we tackle head on the issue of acidification, the future looks grim.

Interviewer: What are the solutions for a better future?

DANIEL: One solution is to deal with carbon emissions. Another would have to deal with preserving habitats and life where it is. That is, we have to create large bases in the sea equivalent to national parks — marine protected areas. Right now the service area of the ocean that is protected, that is now minimally protected, with a declared area, that is point six percent of the world ocean. That is including the Great Barrier Reef and including the great area that has been declared by President Bush- off of Hawaii. Including those giant areas, it’s still point six percent of the world. The areas under protection are growing at about four to five percent per year. Now, four to five percent per year implies a doubling time of about fifteen years. So if you double the area under protection- not effective protection but under nominal protection, you get one point two percent in fifteen years. This is much too small to protect anything. On land we protect about ten to fifteen percent. Most countries protect ten to fifteen percent of the forests, of the wild land. And in the water, we don’t protect anything really. That is really an important thing — that we don’t protect any water area. So put differently, we can fish on ninety-nine point four percent of the ocean. And yet, the recreational fishermen, when we say we need a marine protected area, they freak out.

On land, you protect Yellowstone. You cannot hunt caribous, you cannot hunt animals there, but you can fish. So the idea of protecting fish is counter to our deepest feeling. But we must protect fish if we want to have them. If we want to have fish in the future to eat, fish to contribute to diversity, if we want to have marine habitats intact, if we have the provision of so-called ecosystems services in the sea, we must give them at least as much protection as on land we give to land animals and land plants. And that implies a much larger chunk than we have been up to now considering. And, again, we nominally protect point six percent of the ocean. Ninety-nine point four percent is fishable. This is absurd.

Interviewer: What needs to be done so that by the year 2050 or 2100 so we haven’t lost everything?

DANIEL: One thing that needs to be done is stop the subsidies. The U.S.A. is actually playing a very positive role there in international organizations. An alliance of several countries, including New Zealand and Australia and the U.S.A., have advocated a reduction of fishery subsidies. That would cause those exploiting collapsed stocks to go bankrupt right away. And that would help because the pressure would be reduced on the stock and it could slowly rebuild. Subsidies is a key point. Another is marine protected areas. In California I understand there has been lots of work on stocking the fisheries when they’re on the way to being depleted: turning the Monterey Bay Sanctuary into a real sanctuary, because it had been a sanctuary in name only. You could fish; you could troll; you could do anything you wanted except explode nuclear bombs in Monterey Bay Sanctuary. But now the sanctuary has turned into a thing that will be properly named. There will be no trolling, which is very destructive. That is the kind of thing we can do. The U.S. is actually taking such an initiative seriously. And it is, in relative terms, doing better than a lot of other countries, particularly the countries of the Far East, but it could be doing much more.

Interviewer: Do we have to stop fishing totally or do we just have to stop fishing in certain areas?

DANIEL: I think that fishing can continue in the areas that it has already occurred — where there has been lots of trolling. Fishing should continue to supply people with good, healthy protein. But there should be a network of marine protected areas to ensure that some money stays in the bank. Basically that’s the idea. You put some of your money in the bank so that not everything will be at risk.

Interviewer: If we want to keep some money in the bank, could we just stop fishing for certain types of fish everywhere instead of having designated areas where we wouldn’t fish?

DANIEL: No. Fishing for certain types of fish is tricky because it’s not possible to design gears that have no effect on the non-target fish. That’s the problem of by-catch. For example, you can put hooks in the sea designed to catch tuna- and they catch a lot of tuna, but they also catch a lot of dolphin, a lot of turtles, and a lot of sharks. That’s the reason why drift nets, for example, have been banned; because they caught lots of fish that were targeted, but they caught such immense amounts of by-catch that they had to be banned.

A troll, which is dragging a bag against the ground, is not selective. So they might be fishing for cod with a troll, but they also catch all kinds of things that were not aimed at. That’s one reason. And the second reason is the habitat. There are all kinds of animals that live on the ground, whose role it is to consume the uneaten plankton that falls on the ground, that are devastated every time a troll goes over them.

These animals take hundreds of years to grow — gorgonians and sponges and corals — are devastated. So you cannot have a little bit of fishing because a little bit of fishing, for example, one time a year, is enough to prevent the growth of anything that requires a hundred years to grow. So imagine, you would fish every month or every second month. Imagine you would log Yellowstone, every second month. No, no, that’s too much — every third month, every fourth month. It makes no difference. You cannot log in Yellowstone if you want trees. You could say every three hundred years – that would make sense. But every three hundred years is the same as closing it forever because three hundred years is forever in human affairs. So the idea is to close certain areas off. Imagine you have a sequoia, this big redwood, and it needs a hundred years to grow. If you want sequoias, you cannot have occasional harvesting. You cannot regulate that you can have only small chainsaws. That doesn’t work. You can only have no chainsaws. And that’s why the idea of marine reserves is so hard to get into the heads of people, because they think that the sea is like a meadow. A meadow you can harvest regularly and the plants still grow because they have a lifecycle that is compatible with being cropped. But sequoias don’t and rockfish don’t. The sturgeon that we get on our east coast could not sustain any fishing because some of them take thirty years to become mature. And a fish that needs thirty years to become sexually mature is not a fish that you can exploit with the kind of fishing machine that we have invented and which reduce stocks within ten years.

Series Directory

The Habitable Planet: A Systems Approach to Environmental Science 


Harvard Smithsonian Center for Astrophysics in association with the Harvard University Center for the Environment. 2007.
  • Closed Captioning
  • ISBN: 1-57680-883-1