My two cents on the pulse ban

As I am writing this the European Parliament, the European Council, and the European Commission are still discussing a ban on pulse fishing. Dutch fishers have invested millions of euros in this technology, assuming they would be able to use it for many years to come. And judging by the scientific results so far, they had every reason to do so: pulse trawls have lower fuel use, lower CO2 emissions, less penetration of the sea floor, lower bycatch of plaice than traditional beam trawls. So no wonder they are angry and frustrated at the prospect of a ban.

Most likely it will come to pass. There are plenty of articles on how The Netherlands have lost the battle for the hearts and minds of other EU member states, such as this article in a Dutch newspaper, or this paper by my colleagues at Wageningen University (paywall – sorry!). By and large the experts seem to agree that the Dutch government dramatically overplayed its hand, and that a more careful introduction of the technology may have been more effective in the long run. I can’t judge this but I have two reflections.

Don’t people ever listen?

First, the scientists working on the effects of pulse trawling are also frustrated, and it’s a frustration I also sense with respect to other societal debates. By and large, the scientific consensus is that pulse trawling is most likely better than its alternative, beam trawling:

  • “No injuries were found in fish exposed to the electrical pulses.” (Soetaert et al., 2018, North American Journal of Fisheries Management)
  • “Exposure of Sole embryos at 2 d postfertilization and larvae at 11 d posthatching to pulsed DC used to catch brown shrimp did not result in a lower survival 8 d after exposure. Additionally, no differences in yolk sac resorption and morphometric length measurements of the notochord, muscle, eye, and head were observed in the developing larvae.” (Desender et al., 2018, North American Journal of Fisheries Management)
  • “Compared to tickler-chain beam trawlers, pulse trawlers showed relatively higher discard survival under fishing conditions pertinent to these studies.” (van der Reijden et al., 2017, ICES Journal of Marine Science)
  • “These results indicate that, under the laboratory circumstances as adopted in this study, the small-spotted catshark are still able to detect the bioelectrical field of a prey following exposure to [pulsed direct current] used in pulse trawls.” (Desender et al., 2017, Journal of Experimental Marine Biology and Ecology)
  • “These data reveal the absence of irreversible lesions in sole as a direct consequence of exposure to electric pulses administered in the laboratory, while in cod, more research is needed to assess cod’s vulnerability for spinal injuries when exposed to the cramp pulses.” (Soetaert et al., 2016, Fisheries Research)
  • “Electrode diameter and pulse amplitude showed a positive correlation with the intensity of the fish’s reaction. However, the present experiments confirmed that cod also show variable vulnerability, with injury rates ranging from 0% to 70% after (almost) identical exposures near the electrode.” (Soetaert et al., 2016, Marine and Coastal Fisheries)
  • “In conclusion, under the circumstances as adopted in this study, the electrical field seemed to have only limited immediate impact on the exposed animals.” (Desender et al., 2016, Fisheries Research)
  • “Some of the large cod (n = 260) developed haemorrhages and fractures in the spine, and haemal and neural arches in the tail part of the body. The probability of injuries increased with field strength and decreased when frequency was increased from 100 to 180 Hz. None of the small cod (n = 132) were injured and all survived. The field strength at the lateral boundaries of the trawl was too low to inflict injuries in cod.” (de Haan et al., 2016, ICES Journal of Marine Science)
  • “The evidence presented here suggests that the electrified trawls are superior to conventional trawls regarding different aspects, including ecological impact on the North Sea (less bottom impact), management of commercial fishing stocks (less discards) and carbon footprint (reduction of fuel consumption).” (Soetaert et al., 2015, Fish and Fisheries)
  • “The pulse trawls had fewer fish discards […]. The pulse fishing technique resulted in a lower fuel consumption (37-49%), and consequently in spite of lower landings net revenues were higher. A downside of using pulse trawls is the possible spinal damage of marketable cod (Gadus morhua L.), but because total cod landings by beam trawls are low (4-5%), the implication will likely be limited.” (van Marlen et al., 2014, Fisheries Research)

So to summarise:

  • Cod may indeed be affected more severely by pulse trawls than by beam trawls;
  • For other species the effects appear negligible;
  • There are clear benefits in lower fuel use, greenhouse gas emissions, selectivity, and sea floor penetration.

Basically it’s a trade-off between a possible (but possibly limited) damage to cod versus higher fuel use, greenhouse gas emissions, and damage to shellfish and other benthic life. These scientific findings have led ICES to conclude that “pulse trawling has fewer environmental and ecological effects than beam trawls.

The response by BLOOM, the NGO at the forefront of this crusade against pulse trawling, to ICES’s advice?

twitter.com Bloom_FR status 1002253942108061698

Note that all studies I just cited appeared in peer-reviewed scientific journals. Add to this that ICES is more or less to North Atlantic fisheries research what the IPCC is to climate research, and you see the similarities. How often do climate scientists get to hear they’re only in it for the money? How often do pseudosceptics ignore the vast body of scientific evidence that climate change is happening, that much of it is driven by man-made emissions, and that this is a huge problem? Really, there is not much difference between climate deniers (I’m sorry, I mean to say deniers of the vast current scientific consensus that climate change is happening, anthropogenic, and problematic) and the folks at BLOOM.

And these are not the only examples where science and reason loses against emotions, fake news, and conspiracy theories. Australian green NGOs convinced the government to revoke the license of the Margiris trawler, even though CSIRO found its concessions respected ecological limits. Scientists time and again found no detrimental effects of genetic modification, but opponents pay no attention or refer to studies that have been done so poorly they had to be retracted. And don’t get me started on vaccination.

Perhaps we’re not speaking the right language?

This brings me to the second lesson: all too often scientists expect facts to speak for themselves. It may work like that for us (or so we think, wrongfully), but there is a big bad world out there where there is emotion, cherry-picking, motivated reasoning, political cynicism, and other monsters that will tear that illusion to shreds. Whether we like it or not, facts are not enough if we want our research to have the impact it deserves. Scientists, especially natural scientists (but probably also economists), need to learn that explaining your research is not enough: we must also consider how our findings are being used and interpreted in the wider political and societal debate, and we might need to involve different societal actors in the research in a much earlier stage to build trust and to understand the concerns and loyalties that determine people’s support for, or opposition to a policy.

These two, for me, are the main lessons from this sorry saga.

Work and pleasure, arts and science

One can dream up uncountable categories in any profession, of course, but among academics, and perhaps especially among economists, two types stand out for me: the athlete and the artist/entrepreneur.

Athletes want to be the best in whatever competition they perceive to be in. Rankings are all that matters: all admiration goes to those in the Top 3. Athletes have a strong sense of who is ‘in’ and who is ‘out’: you want to associate with people who are ‘in’ because they publish in all the cool journals, go to the cool conferences and some of that coolness may someday rub off on you. Like real athletes, these academics choose their game, learn the rules, and try to be really good at it. Does this field require me to eschew interdisciplinary research, and prove difficult mathematical propositions? Then by heck I’m going to be the best at it. An athlete is another athlete’s competitor, first and foremost: if other athletes score he cringes his teeth in jealousy and swears to beat them in the next game.

Artists/entrepreneurs want to make a good product. A product is good if they themselves think it is good (the artist) or if it is good enough for a sufficient number of people (the entrepreneur). Artists/entrepreneurs don’t choose games or follow rules: they invent their own game, their own rules. When other scientists produce a great product, like a highly original paper, an artist/entrepreneur is eager to read it, and learn from it. Where athletes are driven by a constant comparison of themselves with others, artists/entrepreneurs are intrinsically motivated: they want to make something they themselves can be proud of.

Fiddle Tunes and IIFET

I have a lot more affinity with artists/entrepreneurs than with athletes – no surprises there. The current system in academia is largely geared towards athletes, with its emphasis on journal citation scores, H-index, and university rankings. This worries me. Athletes may be rule-followers, they are also more likely to cheat – just witness the doping scandals in bicycle racing and other sports. Rule-following also kills creativity – an essential ingredient of science.

IMG_4434 smallI had plenty of opportunity to reflect on the importance of creativity and inventing your own rules in science in the past three weeks. The first week of July I was at the Festival of American Fiddle Tunes in Port Townsend, Washington. It was an overwhelming experience to immerse myself in the music and hospitality of all the folks at this beautiful spot on a peninsula at the Puget Sound. One of the highlights was an improvisation workshop by bluegrass fiddler Tatiana Hargreaves. I don’t want to give away too many details about what we did (perhaps to preserve the secret but actually just because the truth is too embarrassing), but an important lesson that scientists might want to draw from it is that to get out of your comfort zone you should not take yourself too seriously!

DSC00089_smallAnd then there was the conference of the International Institute of Fisheries Economics and Trade (IIFET) in Seattle, in the third week of July. It was my second IIFET meeting but I’m sure it won’t be my last. One of the things I like about IIFET is its broadness, including not only economists but also policy scientists, sociologists, and people from NGOs and the fishing industry. Where the environmental economics conferences can feel like a gathering of athletes, IIFET is the place to go for artists/entrepreneurs. I was also excited to hear that 2020 will see the second edition of MSEAS, a conference on marine social-ecological systems, in Japan! The first edition, in Brest in 2016, yielded what must be the first comic in a peer-reviewed journal – another example of how art and science can make a happy marriage. More of that please!

All knowledge is hearsay

Why do we believe what we believe? One of the many complicating factors in marine policy is that different stakeholders hold different beliefs. Is pulse trawling a boon or a disaster for the marine environment? Do Marine Protected Areas enhance fish catches? Does human activity change the global climate? Finding consensus on how to allocate marine resources is difficult enough when all the people involved agree on the facts. Problems become a lot more difficult when facts are disputed, or worse, when beliefs run parrallel to divisions between political, religious, or other segments of society.

I recently started reading some of the psychological literature on this issue and I came across an article by Dan Kahan of Yale Law School. It addresses the phenomenon that for some policy topics, such as climate change, nuclear power, or genetic modification, acceptance of the scientific consensus correlates strongly with one’s political preferences. In a nutshell, conservatives are more likely to be skeptical of climate science, and to accept the scientific consensus that transgenic crops are safe; progressives, on the other hand, tend to accept the scientific consensus on climate change but are often suspicious of genetic modification. Kahan’s article explains and tests three hypotheses for this phenomenon:

  1. Bounded Rationality. A common theory in psychology posits that our brains have two systems to process information: a “fast” system that works through low-effort heuristics and associations (System 1); and a “slow” system that works through high-effort systematic reasoning (System 2). According to this hypothesis a member of the Dutch Party for the Animals is against biotechnology not because she has read all the literature and visited all the conferences, but because she applies a heuristic that accepts a belief if people like her believe it.
  2. Ideological Asymmetry. Empirical studies have shown that conservatives tend to be averse to complexity and ambiguity: they prefer their beliefs and principles to be simple, clear, and unshakable. According to this hypothesis these preferences make them more closed-minded and less willing to accept facts that contradict their current beliefs.
  3. Expressive Utility. The naive economic view is that values come before affiliations: people hold particular values and beliefs, and then vote for parties and politicians that conform those values and beliefs. A recent publication by political scientists Christopher Achen and Larry Bartels, however, turns this idea on its head: people choose which politician they like, or what party they prefer to associate with, and adapt their values accordingly. According to the Expressive Utility hypothesis, people express group membership through their beliefs: in a sense, they are willing to ignore facts in order to avoid becoming a heretic to their group.

Kahan goes on to test the three hypotheses and he finds that people who use more systematic reasoning are more, not less, likely to align their beliefs with their political affiliation. This makes it unlikely that they use a heuristic (System 1); rather, they invest considerable effort to justify their rejection of scientific facts. This supports the Expressive Utility hypothesis: conservatives are skeptical of climate science because accepting it would make them a bad conservative. I find it a plausible conclusion, particularly considering the findings of Achen and Bartels, and it resonates with other findings that more highly educated people are more skeptical of vaccination.

I’m not buying the Ideological Asymmetry hypothesis that conservatives are inherently dogmatic. I’ve encountered similar closed-mindedness among progressives, especially the radical Left, so I suspect it is more a feature of political extremism than of any particular end of the political spectrum.

Neither am I convinced by the Bounded Rationality hypothesis, although I do think there could still be a grain of truth in it. As far as I understand the dual-thinking model (i.e. as an economist with a half-read copy of Thinking Fast and Slow on his bedside table), System 1 is a fast, associative heuristic: it makes people give the wrong intuitive answer to the Bat and Ball Problem when they don’t have the time or the energy to use the kind of cognitive effort typical of System 2. But climate skeptics or vaccinophobes are not being asked to give their response on the spot. They have Googled the issue, they have read blogs and articles, they have discussed it with friends, relatives, and colleagues. This is not a System 1 activity. But there could still be a mechanism at work that is related to Bounded Rationality – just not in the way suggested by dual-thinking theory.

All knowledge is hearsay

I’m sure there is a theory on this in social psychology or a related field, so I’d be happy to hear about it if anyone who reads this knows more. I suspect that what is going on is that very little of what we know (or think we know, or hold to be true) comes from genuine first-hand experience or logical reasoning. The vast majority of our beliefs depend crucially on information that we got from other people, for example through newspaper articles, scientific publications, radio programmes, and coffee-table chit-chat. Every such piece of information involves a messenger, and whether you accept that information depends on whether you trust the messenger. Moreover, we don’t have time to check all our beliefs, so any time we receive new information we need to decide whether to trust the messenger, to dismiss the message right away, or to verify it with other information – which, again, has to come from other messengers with varying degrees of trust. There will always be a point where we stop verifying and go with the information we have, in other words trusting the messengers of the information we have not been able to verify. So it is not a black-or-white question of using either the heuristics of System 1 or the systematic reasoning of System 2, but rather finding the mix of believing and verifying that leads to an efficient use of cognitive effort.

What makes us trust a given messenger? There used to be messengers with a particular authority, either through formal designations such as college degrees or through informal assignments such as reputations. The views of a professor would have more weight than those of a layman because we assumed that the professor had earned his degree by studying hard, gathering a lot of knowledge, and being really smart; newspapers like The Economist or The Washington Post had solid reputations for honest and well-researched reporting. Both forms of authority have eroded of late due to the increased role of social media and online news outlets, but also a growing anti-intellectualism.

And this erosion of the authority of traditional messengers also points towards another mechanism: we tend to trust people who are like ourselves. A conservative is more likely to reject the consensus on climate change because the Wall Street Journal does so too, and he is more likely to trust the Wall Street Journal than the New York Times. Likewise, an environmentalist is more likely to believe The Ecologist than The Economist on the merits of free trade and biotechnology.

And of course I’m no exception. On all the issues I mentioned above, pulse trawling, MPAs, climate change, vaccinations, and biotechnology, I tend to adopt the scientific consensus. Is that because scientists should be trusted, objectively, to do their work right or is it just because I work in science myself so I am more willing to trust them?

Dutch biologists complain about publishing culture in academia

An interesting article on the current academic climate in the Dutch newspaper NRC Handelsblad: biologists complain about the pressure in the current academic climate not to try to replicate (let alone refute) other scientists’ results, but to exaggerate the results of your own research.

“In my field there are articles in Nature, Cell or Science, of which all experienced people know: this can’t be right,” says Hans Clevers, director of the Hubrecht Instituut in Utrecht and former president of the Dutch Academy of Science, “but rarely does somebody write that explicitly in an article. So every now and again I am approached at a conference by a PhD researcher from a remote university who has been trying for years to replicate that publication. It is very inefficient.” […] Ecologist Raymond Klaassen of Groningen University blames the “short-winded academic climate, that focuses on scoring.” “If you find a deviating pattern in one year, then the current practice is to publish that with a lot of ballyhoo in as high-ranking a journal as you can.”

The Dutch word used in the original article (which I translated here as “short-winded”) is “hijgerig”: from hijgen, Dutch for “to pant”. It evokes an image of heavy competition and short-termism. It reminds me of the atmosphere at a high-ranking Dutch university that has made quite a name in behavioural economics: scoring was the norm, in the best economics journals, but I saw little of a long-term research agenda. Nevertheless, I don’t believe it got as bad there as the biologists describe in this article (knock on wood). I do see it in fisheries science: 2048, anyone?

On interdisciplinarity

Check out the really cool cover of Nature’s special feature on interdisciplinarity!

Of course, as an economist I especially like their inclusion of “Invisible Hand” as the sole superhero representing the social sciences in their scientific team of Avengers. But it is also symbolic for the fact that economists have, in my view, gone the furthest in integrating their discipline with the natural sciences. This holds particularly for environmental and resource economists, who by definition deal with problems of the natural environment like pollution and overfishing. The reason is pretty geeky: most economic research is quantitative, and quite a lot involves the development of mathematical models. And whaddayaknow: so do climate science, population biology, hydrology, and a host of other natural sciences. Give me your equations and I’ll plug them into my CGE model.

It is actually much, much harder to truly integrate qualitative social sciences like sociology or anthropology with quantitative sciences – even with a social science like economics. Models like IMAGE and DICE describe the global climate as well as the economy; the Gordon-Schaefer fisheries model and Colin Clark’s work on renewable resource use, which use basic models from population biology like logistic growth, are part of the standard canon of resource economics since decades; when Daniel Pauly criticizes the limited impact of the “social sciences” on fisheries research, he lumps together economics with biology, not sociology. Meanwhile, it has taken until 2009 that the Nobel committee finally recognized anthropologist Elinor Ostrom for her contributions to the economics of common pool resources, and economists and sociologists share little but contempt for each others’ fields. The Indian economist Jagdish Bhagwati is said to have joked that good economists reincarnate as physicists; wicked economists reincarnate as sociologists. But Ostrom’s Nobel also shows that things are changing, especially in the field of institutional economics. Let’s have more of that in the future.