How Does Climate Change Reshape Conservation Policy?

: Araújo: If you are a scientist working in conservation planning, you want to maximise the benefit of biodiversity. If you are an economist, you don't deny that, but you want to do it in the cheapest way. Then we have the two more, more difficult types of rationality. One is the social rationality and you have different social groups. Each group, they have their own values and there's no optimal function. If you maximise the value of one, you are diminishing the value of another one. And then there's the political rationality. And the political rationality is about maximising power and maximising the probability of keeping it. The more closed are our solutions, the less power the politician has to strike these bargains in order to maintain these power. Scientists coming up with a system that tells what what the politician should do is not going to be welcomed in most of the cases, unless it's it's in the Constitution, in the law. Right? They are forced to do it.

00:00:54: Hahn: Welcome to Inside Biodiversity. This podcast is hosted by iDiv, the German Centre for Integrative Biodiversity Research. My name is Volker Hahn. I am head of the impact unit at iDiv. My guest today is Miguel Bastos Araújo. You will hear how to pronounce his name correctly later on. Miguel is a professor of the Spanish Research Council at the National Museum of Natural Sciences in Madrid, and he is also affiliated with the University of Évora and the Imperial College London. Miguel is currently spending several months at iDiv as a sabbatical researcher. In this episode, we will discuss how climate change affects biodiversity and how this knowledge can inform better conservation policies. We will also talk about competing rationality in conservation and how researchers can play a productive role in the science policy interface. Let's begin. Miguel, welcome to Inside Biodiversity.

00:01:57: Araújo: Thanks for having me.

00:01:58: Hahn: What's the correct way of pronouncing your name? Because I would probably fail, so I'll let you do that.

00:02:05: Araújo: So my name is Miguel Araujo and it is the Portuguese pronunciation. In Spain they call me Araujo. When I was in France I was aroozoo and in English could be a rougeau or rougeau. So many different. I don't know how, how, how do you say it in German? I would say.

00:02:23: Hahn: Araujo.

00:02:24: Araújo: Okay. Okay.

00:02:26: Hahn: Yeah, that would be a very German way of pronouncing it.

00:02:29: Araújo: Yeah, I don't mind.

00:02:30: Hahn: Okay. Tell us a little bit about yourself. And how did you become interested in biodiversity, geography and what motivates you to pursue this career as a researcher?

00:02:44: Araújo: Well, um, as far as my memory goes back, I think I've been always passionate by, you know, the natural world in a broad sense. And but I believe that retrospectively, the context matters. My father is a biologist. And when I was young, very young, you'd take me to the woodlands in Belgium and we'd collect insects and bring them home and observe them in a, in a terrarium. So this was fascinating. But also my grandfather. He was born and raised in Mozambique, in Africa. And he was, amongst many other things, a wildlife photographer, but also a hunter. So he had many stories of of the jungle adventures that I was fascinated by them. So when I was 13, I and people asked me what you wanted to be when you were grown up, and I would say zoo geographer. And uh, later on in Paris, I stumbled into a bookshop where I found a book by Jacques Blondel called, um, Evolutionary Biogeography. And I when I read the book, I thought, well, this is what I want to do. And, you know, and that's what I did.

00:03:50: Hahn: Yeah. Very cool. So you, um, a lot of your research has to do with climate change and how Nature responds to a changing climate. How can a specimen react to a changing climate? Or is that even maybe the wrong question? Do we have to look at the at a species at a whole?

00:04:13: Araújo: Well, I think we can start looking at the species. And there I think conceptually we can think of two. Two ways to formulate the problem. On one, the more classical, if you like, is the critical limits of tolerance. We all have a range of temperatures and that we can cope with. And and that's our climate envelope, right. So not just temperature but many other variables. And and that is associated with our physiology. We cannot tolerate too cold. We cannot tolerate too warm. And so that's the first the first angle with which you can explore the problem. The second is related to what we might call the critical, uh, resource limits. The resources drink we we the water we drink and the food we eat. It might change also collectively when changes in climate. So when you're looking at, uh, how climate change affects organisms, you can look for these two angles, uh, the critical limits of tolerance and, and how the resources change. And that leads to fundamental different ways of, of investigating the problem.

00:05:23: Hahn: So one way that species can respond is to migrate. Others are there's adaptation. What kinds of adaptations are there?

00:05:34: Araújo: If you don't feel well in a given place, you can move. If you can, you can adapt by changing behaviour. For example, if you are, if you're an animal, you can adapt by changing your habits. You may change your phonology, for example, which is like you'll read earlier, you'll migrate later, you will hunt in a different time of the day or forage in. You know, if you are a herbivore, you also forage in a different time of this. So so there is a plasticity in, in in how you can adapt to climate change. It does not involve a change in the organism itself. And then of course as adaptation genetic adaptations, which leads to a change in the makeup of the organism and its ability to cope with different environments, both of these processes coexist. But of course they have different timings.

00:06:20: Hahn: Yeah. And then.

00:06:22: Araújo: And if you fail to adapt, you die.

00:06:24: Hahn: And of course, a plant cannot migrate in that sense. But it can disperse and it can become more successful or successful in an area where it wasn't successful earlier because the climate has warmed. It has, or less successful, of course. So all of that contributes then to a change in the distribution of species, which is your expertise. What can we observe today? How are species distributions changing because of climate change. Can we already observe shifts and distributions?

00:07:04: Araújo: Yes. I mean, generally there's, um, a global pattern of movement of species from the equator towards northern latitudes, and there's a contraction of ranges. Of course, before there's a shift, there's a change in abundance. Right. We usually have we don't have much abundance data to that. There's now.

00:07:27: Hahn: Abundance is the number of individuals.

00:07:30: Araújo: Right. A shift occurs when abundance goes to 0 in one place and and goes to plus more than 0 in another place. So and there's transient changes in in abundance that we often don't see or we don't document before a range shift actually occurs. But there is been measured, for example, in the UK, um, in the past 25 years, um, shifts in ranges on average among insects and birds, and some plants and other vertebrates. Of about 31 to 60km north and 25m in altitude.

00:08:07: Hahn: Within what time span?

00:08:11: Araújo: 25 years. But if you have, you know, colleagues that are measuring those shifts on the ground, for example, in Spain, in the mountains, in the mountains north of Madrid, and you can see also movement shifts in the distribution of butterflies in altitude. So this is this is a process that is happening now and it has happened in the past is a normal adjustment of ranges of species track the climate. So so that they try to, you know, they maximise their fitness.

00:08:39: Hahn: There are probably those species that may benefit, at least in a certain area, from climate change and others who will lose out because the conditions become worse for them. What can we say about that? How many winners and losers are there. And are there certain groups of species that in general they're more on the winners side and others more on the loser side? What are the patterns there?

00:09:08: Araújo: There's clearly a trend towards favouring warm-tolerating species and species that are cold adapted, suffering more so species. For example, in northern Scandinavia and in tops of mountains, they tend to be shifting further north and further further in altitude, and then having to compete with species coming from below or from the south. Right. So those are clearly, um, becoming refuge species. They were already refuge species because we live in in a fairly warm times. We are in a interglacial that is a period between, uh, glacial periods. So warm period. So those species that were adapted to colder were already cornered in the top of the mountains and in, in the high latitudes, and they are now, uh, there's a driver pushing them further north and further in altitude. So those, you know, if you like to use your words, they would become losers. They are losers in the current in the current scheme of things. And then the species that tolerate warmth, they will they will expand. They are already expanding.

00:10:15: Hahn: That also means that we have some areas, maybe in general, the colder air areas where the number of species might actually increase. Yes, yes, in others more in the warmer regions where we can expect or already observe that species, the the species richness or the number of species is decreasing.

00:10:34: Araújo: Yes, for two reasons. One reason is that the pool, the pool of species on Earth that tolerate warmth, is greater than the pool on Earth that tolerates cold. Um, so there's more species, um, available to colonise, uh, areas that become suitable because they become warmer than colder species on Earth. So there's that imbalance will cause increase of species richness locally because there's more species coming in than the ones going out. But also, uh, productivity will increase. Warmer temperatures associated with, uh, greater amounts of water availability will increase the quantity of energy available for consumption. And if energy available for consumption increases the immediate reaction. The immediate response is an increase in the number of organisms that can that can exploit. And it can be different, more individuals of the same species, or it can be more species. So these two patterns, both on the on the tolerance limits that I mentioned earlier on and on the critical resources, uh, aspect, uh, favour and increasing species richness in higher latitudes and higher altitudes as well.

00:11:46: Hahn: In your research, you've been heavily involved in developing computer models that describe and explain these patterns and these changes caused by global change drivers, especially climate change. Can you tell us a little bit how these models work in a nutshell?

00:12:08: Araújo: Well, I mean, there are many different modelling techniques. I've been working mainly with what is called specie distribution models and specie distribution models. There are biogeographical models. They examine the distribution of species. And they you know, if you likely correlate those distributions with a range of predictor variables, including.

00:12:27: Hahn: Like a map that shows us where are the species and how many and

00:12:33: Araújo: Yes. What those models do, they try to characterise that climatic envelope of every species? Right. The range of tolerances the species can cope with by correlating where they are with the climate they are exposed to, and assuming that where they are is where they can be. Which is a big assumption, but that's the assumption of the models. Then you characterise those range of conditions where they can be And then you project into the future as the climate changes into the future, you can also project back into the past and and then use the fossil record to test, to test the models or examine what might have been the past. So there are several uses, but that is is a that is by far the most common type of models to, to to study biodiversity in space and time. You can also have other types of models that instead of focusing on the pattern because we study the pattern, try to infer the process from the pattern. There are other models that start with the process, so they model the process mechanistically if you like, and then they try to infer broad scale patterns from running models that focus on the process. And they can also be based on species, for example models. And now I'm going to use this jargon metapopulation models. Right. Models that study process like birth rates, death rates and dispersal. And they encode the model with information about the displays, the dispersal capability of species and what their expected death rates and and birth rates. And based on that information, they try to see how the species might, might change through time. Um, so that's that's a different type of model. And then there's, there are other models that instead of focusing on the composition of how, um, biodiversity from this compositional aspect, you know, what species occur. They focus on function, how the ecosystems will change. And for example, models like the LPJ models extending from Lund, Potsdam and Jena because it was developed by scientists from these three universities, people like Colin Prentice, Wolfgang Cramer and Martin Sykes. Um, they developed vegetation models based on plant functional types. So the unit of analysis is not the tree per se. The composition, that evolutionary unit is how they examine the collective properties of many plants that share the same functional type. Right. So. And what, what they try to do is to see how how those traits will change with time in response to climate change and what our functions are changed, like for example, CO2 cycling, nitrogen cycling, etc.. There's a new type of model that we are now starting to develop that is also focussed on on the function. But instead of being mechanistic in the sense that I've just described for the for the, you know, the vegetation models, they are pattern oriented, but they, they function based on they, they process analysis of functional groups rather than species per se. And those functional groups in the way we are addressing them. They are, um, trophic guilds, that is, groups of species that share a similar diet. And what we find is for animals, um, the, the currency that we are interested is not the functional types as is as for plants, in plants, these functional types, they reflect, um, eco physiological responses of species to climate. So you know that principle of limits of tolerance. Um, in animals, especially if you think about indoor terms. Uh, species that can, uh, thermo regulate and just.

00:16:04: Hahn: Like us.

00:16:05: Araújo: Like us. Um, we have many strategies to cope with, um, um, changes in climate. While in our case, we can, you know, we have have coal, we can have clothes, move indoors, etc. but if you are, um, another indoor term, uh, with less access to technology, let's say that you can change your behaviour, you can move, etc.. Um, so these models, they look at patterns as patterns in the distribution of the gills and they recover function from that completely different approach still in its infancy.

00:16:37: Hahn: Can you say a little bit about the uncertainties associated with these models, like if we project biodiversity in the year, I don't know, 2100, there's so much uncertainty about how climate will change. There are different scenarios. There are also other drivers than just climate and then uncertainties about how good are these models and how how well do we actually know how species respond. So how far in the future can we look using these models?

00:17:09: Araújo: Uh, that's that's a hard question. Uh, we can, you know, conceptually think of two lines of of uncertainties. One would be what we might call algorithmic uncertainty, the uncertainty associated with the models, which you can study through mechanisms like sensitivity analysis, which can trick aspects of your model and see how different your results are going to be. Um, and that kind of uncertainty, we call it variability model variability. And, and we have uncertainty in the, you know, response variables like the distribution of species in the predictor variables into the climate variables that we use, for example, uh, in the models that we use and in how the models are parameterised. And then of course, when we are interested in climate change, also in terms of what kinds of futures we are assuming when we project our, um, uh, climate change scenarios into the future. So these, these is a series of models that is not just additive, it's multiplicative. And the more you go, um, further in in the future, the greater those uncertainties are. Um, but that's because we, um, we don't extract any emergent property of our data. You know, individual species don't really have emergent properties. They respond. Um, we might say idiosyncratic, following their own rules to climate. When you, for example, if you model, um, vegetation or vegetation types, uh, you're not modelling the response of the idiosyncratic response of individual species. You are modelling a higher level property which relates to very well established relationships of functional types with climate, and these are much less error prone. So for example, if you if you have a forest with, um, if you have a mangrove that depends very strongly on a certain types of conditions where mangroves leave, uh, if you model, uh, model species A or species B, you, you might have some uncertainty about the response. But if you model the collective distribution of the mangroves, it will be easier because they have a much more deterministic response to climate.

00:19:27: Hahn: And that's an approach you try to increasingly use.

00:19:31: Araújo: Exactly, exactly.

00:19:32: Hahn: So, so you are trying a lot of your work is about reducing this uncertainty. Is that correct?

00:19:38: Araújo: Yes. Most of my research in the in the early days was about trying to understand the algorithmic uncertainty of the models, trying to contain it, and we've developed this approach called ensemble forecasting, where you generate several models, you tweak the models several times, you generate a cloud of uncertainty if you like, and then you combine those results in order to reduce them, you know? Just focus on that consensus of the models. That's an approach that is used not just by us, but it's very common in climatology, even in economics, stock market forecasting, etc.. So ensemble forecasting is, is is now mainstream when we're talking about trying to, to project the future or the past. But what I'm really interested is more about what we might call the ecological uncertainties and, and try to find out ways where we can reduce the uncertainty associated with ignorance. The things know the things we don't know. We don't know. Right. And when you when you focus on, on, on individual species, you can develop ever more complex models for that particular species. But if you are interested in biodiversity, you can count the number of years you need in order to get a a good understanding of the millions of species that exist on Earth. Develop one model for each one, and then there are problems of interactions amongst those species. If you want to factor them bottom up, you might get to a point where you don't really understand what's going on because there's there's butterfly effects, right. Chaotic dynamics. Whereas if you model, um, emergent properties of those ecosystems where those species, um, exist, you don't need to model every individual part of the system. You model those properties. And what we're finding is that we can find general properties emerging, not just in vegetation types, as it has been shown already for many years, but also in animal communities. And that's fascinating.

00:21:36: Hahn: Let's talk about how these modelling approaches are linked to conservation. Why do we need these models in order to improve conservation, for instance for selecting protected areas, because protected areas might harbour different species now than they will in the future. So tell us a little bit more about that.

00:22:02: Araújo: Yeah. Well protected areas, um, they can be they can be established for several reasons, not just for the conservation of species, but for other, other purposes as well. But but let's focus on, on that particular, um, application. Uh, typically protected areas were established in order to isolate biodiversity from the threatened, from the threatened, the threats of human activities. And underlying that principle is the idea that if we maintain, if we manage to protect them in that arc, um, isolated from, um, hostile environment, the species will be, will be, will be safe forever, right? And, um, with climate change, uh, we know that's not going to be possible because one main way for species to adapt to climate change is to move and go to other places where they can survive. So that brings us to focus the idea of um, of either, um, establishing connections between protected areas so that they can move between this network of areas or even create new hubs in the network, new protected areas that currently are not seen as important but might become important as as the climate changes. So how can we anticipate those changes? Well, is with models and then species distribution models proved to be quite um, effective um in as a tool to, to anticipate those changes because a lot of conservation is still focussed on focusing on, on focal species. So if you are interested in the links in the bear, in the wolf, for example, then you can model those species and you can predict where are suitable environments. So for example, in a recent study I've developed for Portugal, Um, we find it found out that, um, there are some areas in the northeast, in the mountain ranges that are likely to become refugia for species. And when I talk about refuges, I talk about two types of refuges the retention refuges, where species will not need to move because the climate will, um, um, maintain stability within the range, within the envelope of the species. And also what we call a displacement refuge, which is where species are not currently present but might become present in the future. And interestingly, all that area north of Lisbon, um, the coastline north of Lisbon is projected to become, um, a displacement refuge, an area where species are currently not. But they will go because it remains cool and and fresh, um, because of the of the oceanic breezes. Right. And so this is interesting as an instrument for, for planning.

00:24:41: Hahn: So north of Lisbon, if you glimpse into the future, you can project with some certainty that those areas will be important for species in the future, even though they are not that much at the moment. So it's informative for conservation today. Looking into the future.

00:25:03: Araújo: Exactly, exactly. And of course, it's an area where there's a conflict. It's an area very valuable from a, um, human-centred perspective, for example, these scenarios of big waves and surf, it's it's around that area.

00:25:19: Hahn: Yeah. That already brings me to, uh, to the next point, because you can use these models to identify like technically the, the best areas, most suitable for, for conservation for a specific set of species. But there are other interests. And, uh, you recently had an opinion paper you call this conflicting rationalites. And in that paper you say that the practical uptake of these, let's say, technically based recommendations for where a protected area could be remains limited because of these conflicting nationalities, conflicting interests. And you develop a proposal how to deal with that. Can you tell us more about it?

00:26:07: Araújo: Yeah, I mean, it's sort of this paper is interesting because this is part of the discussion of my PhD thesis that I finished 25 years ago. And, and the reason I stopped working on that topic, on conservation planning at the time and focusing on, on climate change, was that I felt that nobody was interested in scientific approaches for spatial conservation planning, and there was no interest. And in trying to investigate why there wasn't an interest, I realised that we were provide answers and answers that nobody was asking. Why is that? Um, because we are all, um, sons and daughters of the enlightenment, right? We believe in rationality, but the rationality that we believe is what we might call the scientific or technical rationality. We want to have access to the best information to to produce the best answer, to maximise a given function. In the case of conservation planning, we want to maximise the benefit of biodiversity and given the data, we try to find what is the best solution for that. But we don't live in isolation. We live in a much more complex world where there are other actors and they don't share our rationality, or at least they don't prioritise it as much as we do. They have other types of rationality. These are values or the values is not is that they are dumb. They just think in a different way. They try to maximise different functions and we need to understand that. So for example, if you are a scientist working in conservation planning, you want to maximise the benefit of biodiversity. If you are an economist, you don't deny that, but you want to do it in a most efficient way, in the cheapest way, because you want to to minimise cost. But that's fine. Minimising costs is can be part of an algorithm with which we work. Then we have the two more difficult types of rationality. One is the social rationality, and you have different social groups. Each group they have, they have their own interests, their own values, and there's no optimal function. If you maximise the value of one, you are diminishing the value of another one. In fact, there was a Nobel Prize in the past that said there's a theorem of impossibility that he demonstrated in social science. It was impossible to optimise the values of different interest groups. And then there's the the the political rationality. And the political rationality is about maximising power and maximising the, the probability of keeping it. And that involves power of, of of negotiation, the ability to, to strike deals with different interest groups and accounting at the same time, if possible, for the scientific and economic rationality. But the more the more closed are our solutions, the less power the politician has to strike these bargains in order to maintain his power. So scientists coming up with a system that tells what what the politician should do is not going to be welcomed in most of the cases, unless it's it's in the Constitution, in the law. Right? They are forced to do it.

00:29:03: Hahn: That reminds me of this narrative “Follow the science”, which is kind of like advocating a single technical solution for solving a problem. And that doesn't agree with what you say about conflicting rationality. What do you think about this narrative? Follow the science. And what do you think is a good role for researchers who want to inform policies? What's a good and productive role that will lead to better conservation policy?

00:29:39: Araújo: Well, that's a topic that I have great interest in. And I think one one analogy or metaphor that one might think is a medical doctor environmentalist. They study systems and in a way, what they want is to cure the planet Earth, cure biodiversity, bring health to ecosystems. Right. And a medical doctor tries to do the same, but with people, with humans. But we don't have medical doctors. Um, setting. Um, um, health care policy. I mean, they of course, they they contribute to it, but their word is not the last word on those topics. Why? Because that policy has to be balanced with other policies. And that's the role of of the politicians. And I think we are in a very similar situations. We we don't have as clear ideas as how to solve the problem of ecosystem health as the medical doctors have, because after all, the human body is simpler than ecosystems. Um, so our science is a lot more Complicated. And we still, um. Well, there's less funding for it, let's be honest. But, uh, we do have some, some, some some solutions. We do have views on how we can improve the health of the ecosystems and conserve biodiversity. But from that to providing the ultimate solutions that are inherently political, that's a big step. And I have nothing against we stepping into politics or acting as engaged citizens, even, even even becoming politicians. Um, if we feel the urge to solve some problems more effectively, I think the problem lies on when to try to win arguments and persuade others. We we come with arguments with authority. We are the scientists. We know about it. You don't know anything about it. And if you if you enter with arguments of authority backed up by science, um, science becomes an object of political discussion. And we see we can see what's the end result of that?

00:31:47: Hahn: So it can fire back.

00:31:49: Araújo: Exactly.

00:31:50: Hahn: On science

00:31:51: Araújo: Exactly. If if not careful enough. You know, science, after all, is is a methodology for acquire knowledge. Um, you know, society believes in science to the extent that that methodology and is, is, is robust and the opinions of everyone do not corrupt the methodology of the methodology. Um, if we mixed our opinions with what is the knowledge that is acquired systematically and and robustly and we we, we add our opinions on top of it to to win an argument, um, we lose the credibility, but it's not just us. Um, the problem is that there's, there's, there's, um, a chain effect and it might backfire to the whole, um, scientific system. That is a is a very expensive cost.

00:32:43: Hahn: To end this conversation, can you summarise in a nutshell, what would you like the listeners to remember from this conversation in a week from now?

00:32:54: Araújo: I think it's important to realise that more technically that when we addressing climate change, um, we have these two different strands that I mentioned earlier on, one that is related to our climate envelope, what we can tolerate and not tolerate in terms of um, changing, um, climatologists. Uh, and that's a it's an organismal response. And then there's an ecological response, if you like, which is the climate is affecting the distribution of several organisms. And collectively, each one of them is a resource for other organisms. So that's going to affect the network of biotic interactions is going to affect the ability to feed. Um so these are these are these are two different processes. They operate um, in. They are at the same time, uh, but they have to be studied and modelled in a different way. A second message is that, um, current conservation policy focusing on protecting the distribution of species today are incomplete. In fact, is, um, I didn't mention that, but, um, it's somehow curious that we collectively, environmentalists are forcing natural states to, um, adapt to modify policy across the board. You know, in all almost all areas of, of polity and are so resistant in changing conservation policy to be informed by climate change. So we want the energy sector to change the construction section to change, uh, the transport uh, section to change. But we're not doing the homework in conservation policy, even though we know a lot about it. So we need to adapt our conservation policy to climate change. Third, and to end, um, I think we need to have a serious thinking about our role as scientists and citizens in addressing those crises. We have to be, um, aware that if we don't pull the strings in the right way, uh, we might be exposing the scientific infrastructure, science as a whole, uh, into a situation where we don't want it to be, you know, to be, uh, politicised and to be defended by just one, um, in one, one axis of the political debate. We we don't want that. We want science to be a consensus. We want to be society. We want society to, uh, trust, uh, science trust education. Um, and to want to fund it, to maintain a society that is, uh, informed by the best, uh, available knowledge. Uh, and that requires a serious thinking about our individual, um, uh, attitudes when we engage in public discussions. I mean, I'm a very active, um, person on a on a citizen level. You know, I've written in blogs, I write in newspapers. Um, I've also maybe in the past and now engage, uh, publicly in a lot of discussions on environmental issues, but I always try to separate those. What is my opinion? I have the right one to have one. And what is what is what are what are facts? As much as we can have facts. Um, and try to engage in, in, in constructive discussions.

00:36:30: Hahn: It was a great conversation. It was a pleasure to have you here, Miguel. Thank you.

00:36:33: Araújo: Thank you very much

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