A Conversation with Callum Roberts on the Disastrous Turning Point for the Ocean 

May 2023 (Part 2)

Renowned marine ecologist Prof. Callum Roberts agreed to speak to The Tyler Prize about our 2023 Laureates, Rashid Sumaila and Daniel Pauly.

This is part two of a two part interview. In this section, Prof. Roberts delves into the influence of Daniel Pauly’s publications on his own early work, Rashid Sumaila’s vision of ‘infinity fish’, and the importance of seeing the ocean as a global system.

Click here for Part 1

Callum Roberts with OW

As a fellow marine biologist, what was your first interaction with the work of Daniel Pauly, one of our 2023 Tyler Prize Laureates?

I’ve been studying the oceans for a very long time. Back in the 1980s and 1990s, I was fascinated by coral reefs but by the ‘90s I realized that they were beginning to struggle under the onslaught of human influences. It was at that point that I first discovered that fishing was having a profound influence on marine life. So I started reading papers on fishing and of course I almost immediately landed upon Daniel Pauly’s work. I saw that we were kindred spirits; looking at the impact of people on the ocean and trying to understand how we could use the oceans better to preserve fish and maintain all of the good things that the oceans give us.

As a fellow marine biologist, what can you tell us about Daniel Pauly’s work?

Daniel has achieved so much over the course of his career, and any one of those achievements for any normal scientist would be their lifetime contribution. But not for Daniel, he didn’t stop there. Daniel’s major achievements have been to really put fish on the map for many people, to provide the tools that are necessary for people to undertake excellent science, to understand fish better, to enable the world’s fishing industries and those who oversee them to understand what impact they’re having on ocean life, and to understand how they can have less impact to make fisheries more sustainable over the long term.

I think one of the things that Daniel has done is to give us new ways of seeing things that are very important phenomena, but which have gone unrecognized. And one of his great insights was into what’s known as the shifting baseline syndrome whereby, as the environment changes and declines, older people will have seen a bigger decline than younger people. Younger people’s baselines are set in their youth. The amount of wildlife around them is what they think of as normal and declines then seem smaller from that new baseline. Another one is the idea of fishing down the food web. It’s a phenomenon that others of us have observed, that big fish are becoming rarer whilst small fish are more abundant over time. But by labelling it as Daniel did, it allows people to intuitively understand the nature of the change in a very simple and conceptual way. And I think that has really led to a whole new area of investigation which has proven extremely fruitful.

What roles have Daniel and Rashid played in addressing the challenges that the world’s oceans face today?

Daniel and Rashid have been incredibly powerful advocates for change in practice by governments, regional development organizations and anybody who promotes fishing. They have taken their message across the world, saying look: we are doing it wrong at the moment, we know there is overexploitation taking place. We know what the problem is. If you take too many fish from the seas, you will have fewer to take in the future. And if we want to be sustainable in our activities, in our businesses, in our industries and if we want to sustain communities and give them access to food over the long term, we’re going to have to do things differently. They have taken to the world stage and have been relentless in talking about the problems and the solutions to anyone and everyone. I think that’s what singles them out as being different from most people, who sit in their labs and publish their papers. Both Daniel and Rashid realize that if you want to make a difference, you don’t leave the paper at the computer, you take it to the next stage. You make sure that the people who are able to act on the results and bring about change understand your papers and the science that makes it possible for them to make better decisions. Of course, better decisions don’t inevitably flow from better data. And that’s where you have to be dogged in your determination not to let go of this problem and to make sure that it’s heard all the way to the highest levels of the United Nations.

As you mentioned earlier, coral reefs, like a lot of marine ecosystems, were struggling by the 1990s. What did the data available at the time suggest about the state of marine life?

The Food and Agriculture Organization of the United Nations (UN FAO) have been compiling government statistics on fishery landings for a long time. That was the data on which most people based their perceptions of how well fisheries were doing. That data showed a gradual rise followed by a leveling off in fish catches. At face value, that graph looks fine. Their argument is that the data shows that we’ve intensified our fisheries, we’ve built up the world’s fishing fleet, and now we’re in a steady state where everything is sustainable. And yet that isn’t what’s going on. There were worrying signs of sustainability in the data early on, but they were concealed by aggregating all of the fish together.

Daniel Pauly is well known for his work on creating large data sets. What was Daniel’s role in challenging the data presented at the time?

What Daniel Pauly did was to closely examine the data that was presented and he identified that there were flaws. He could see that we weren’t recording everything that we caught and we weren’t looking at how the composition of catches was changing over time. What we needed was a much better database of fish landings to see the detail of what was going on. Daniel’s work revealed that the ‘leveling off’ that had previously been identified in the data was actually an indicator that we had reached the maximum number of fish that could be exploited. Now we’re seeing serial collapses of fisheries around the world. Many of the species that we caught in the fifties and sixties are no longer abundant. They’re essentially economically extinct.

What was the role of the Sea Around Us, the database founded by Daniel Pauly?

One of the things that Daniel Pauly dedicated the last decade or so of his career to is reconstructing the world’s fish landings from scratch. He realized early on that there was a great deal that the FAO were not including in their statistics, for example any fish that was caught but not traded which includes all the fish caught for subsistence, also fish that were caught but thrown over the side of the boat because they were over quota. So, Daniel assembled a big team and set out to reconstruct all of the fish that we catch, not just the ones that governments report on. Daniel found that catches were being substantially under reported.

What impact have FishBase and the Sea Around Us had for fisheries scientists in the Global South?

What’s needed to manage a fishery well is knowledge. FishBase and the Sea Around Us gives fisheries scientists the global experience of fishing, both unsustainably and sustainably, at their fingertips. If you have access to that information, then potentially you can make better decisions about how to exploit fish stock in perpetuity rather than just for the short term. The databases that Daniel has built have given so many more people the tools to be able to do excellent science, and particularly in the world’s South where there are not the great libraries like there are at Harvard, for example. That has democratized the whole field of fisheries science. And I think that is an enormous contribution. He’s hugely deserving of the Tyler prize for that alone, but there is more: building from scratch all of the data on fishes and landings over time… I’m lucky enough to be working with Daniel to try and unlock a new insight into how the world’s continental shelves have been impacted by fishing gear disturbance of the sea, and how much carbon that might have released in the atmosphere over the course of history. And because he’s got this incredible data set at his fingertips, we can simply plug that new scientific question on top of it and reach answers far more quickly than we could have done if we had to build a database from scratch ourselves. So it’s enabling people to answer new questions, important questions faster than we could answer them before.

What do the advancements that scientists like Daniel Pauly and Rashid Sumaila have made in fisheries data show us about the state of the world’s oceans now?

Fishing activities are far less sustainable than we thought. The impact of fishing is far greater than we thought that it was. What we can now see very clearly is that fish landings are declining over time and not leveling off as the FAO data seemed to suggest. Statistics suggest there is a decline of about a million metric tons per year in wild fish landing. Unfortunately despite the urgency and the gravity of the situation, a lot of the world’s governments are still listening to the voices telling them that everything’s fine, that we can carry on developing fisheries and increasing investments. In India, for example, many in power still think that it has a huge amount of fish offshore that can be developed to feed its people but actually history tells us otherwise. Looking at the position of fish landings in India today, you can easily look at them and say – you’re running out of fish.

How would you characterize the impact of Daniel Pauly and Rashid Sumaila’s work?

Daniels and Rashid’s work have transformed the way that we think about the ocean. Previously we thought of it as an inexhaustible source of fish to feed humanity forever, but what we realize now is that it is a finite resource and that it’s being drawn down over time and that the value of life in the sea is less than it was before. This is having a profound impact, not only on fisheries and the people who depend on them, but also on the way that the ocean functions. And if we don’t change the way we go about exploiting the ocean, then we’re going to lose a great deal more than just fish. The ocean itself is fundamentally important to the habitability of earth. It’s huge compared to the size of the terrestrial biosphere. The ocean occupies something like 97% of the living space on the planet, which means that what goes on in the sea is of absolute importance to everything else that happens on the planet. We realize now that it is not impossible for people to alter that in damaging and harmful ways. And we realize through the work of fisheries and fish statistics and biology that we’ve got a problem here that needs to be fixed. And if we don’t fix it, then bad things will happen to all of us.

Daniel and Rashid’s work is showing us how to fish better for the benefit of many. Both have been powerful advocates for the rights of small scale fishers who depend on fish for their nutrition and for their income, for their wellbeing. Industrial fisheries are robbing many countries of the resources that they depend on most. And I think Daniel and Rashid have spoken out on behalf of people in Africa and Southeast Asia whose rights are being trampled on by industrial conglomerates. And if that was their only achievement, that would be worthy of a prize too. Daniel and Rashid are bringing the world’s problems into the decision making hall of the world’s rich and forcing people to confront the issues which are leading to worse livelihoods to poverty and malnutrition in these communities and to understand their culpability and role in that situation and to give people the tools to change that and to improve the outlook for so many people across the world whose lives revolve around fish and the ocean. I don’t think Daniel and Rashid will ever retire. They are absolute powerhouses of scientific and economic thought. I think they’re gonna be working for a better world until their last breath.


May 2023

To read more on Dr. Callum’s incredible work:

Youtube: Future Ocean with Callum Roberts

Faculty Website: Dr. Callum Roberts, University of Exeter

Wikipedia: http://Professor Callum Roberts