Hugh Possingham is one of Australia's most respected mathematicians, whose work has fundamentally influenced nature conservation. However, the enfant terrible of his field regularly provokes his colleagues and the public with his opinions. What these scandals have taught him, why he continues to make confrontational statements and what benefit he sees in scientific conferences, he reveals in the following interview.
His career is associated with a long list of conservation achievements, for example he contributed to the creation of the Brigalow Declaration, which significantly reduced the destruction of rare biotopes in Queensland fifteen years ago, or the Marxan software, which calculates in which place it is best to establish a national park or other protected area.
What brought a professor of mathematics to professional nature conservation?
We have a chief entrepreneur in Queensland, and he once said something interesting. Instead of wanting a career or a job, more young people have a purpose. When I was leaving high school, I didn't envisage any career at all, I only wanted to save biodiversity and habitats I loved. Science and mathematics were just an accidental career, the biproducts of my purpose.
In some sense, it was a luxury, as most parents force their children into picking lucrative careers if they get good grades at high school. But my parents said: Do what you want to do, achieve what you want to achieve. I never thought too much about that until very recently, when I realized that most people still don't have the luxury to choose a purpose, most people still must choose a career.
And do you manage to fulfill that mission? What are you most proud of in your profession in this regard?
The Brigalow Declaration. It is tricky to explain to someone from Central Europe. Basically, most of the Czech Republic was covered in ice 15 thousand years ago. So, if you stop ploughing a field and just let it be, it will probably be a very functional ecosystem within 200 or 300 years again, because all European ecosystems are quite resilient and able to rebuild themselves. But most of Australia has never been covered in ice, so when people destroy ecosystems here, they're doing something that’s almost irreversible, as recovering of an Australian habitat could take tens of thousands of years. When I compare this to climate change, which - and this is a confronting statement – will probably get fixed in the next two hundred, maybe even fifty years, evolution will take two million years to restore the diversity after we wipe out half the species on the planet. To me that was very upsetting. The Brigalow Declaration reduced habitat clearing in Queensland from a million hectares a year to fifty thousand hectares a year. That saved about five million hectares of habitat, which is around five billion trees, and 100 million birds, all saved from habitat destruction. That's the most important thing I've done and that’s why I continue to campaign about habitat loss and degradation.
Your love of nature was sparked by your father who brought you to bird watching. He also gave you a book about bird communities by Martin Cody which showed you that mathematics and ecology can be usefully connected. Could you tell me more about that connection?
Besides Cody’s book, I also read the work of Robert MacArthur, the most famous ecologist ever who trained as a mathematician first, and a physicist Robert May. He and MacArthur started to use mathematics to understand the way the world works. They turned ecology from a descriptive science to a quantitative science to build order and structure.
That said, what I've done in my career is similar, but different. I’ve been asking how mathematics can solve problems that are important to conservation, which immediately leads you to problems of optimization, economics, and allocation. For example, how do you save the most species for fixed resources, or how do you build an adequate system of protected areas for the least resources. That's the mathematics I became interested in, and that became very useful because very few people were using that sort of thinking in any of conservation in the 1990s.
As it was a new approach, how did people react to it?
Well, there are still people who don't like the idea of using maths and economics to deliver biodiversity ouctomes. They find it confronting because often when you talk about optimization and species, people worry about the idea of triage – allocating funds only to some species and letting the others go extinct. I can see why Europeans don’t like triage – they have relatively few species and through great policy and intensive management many species are recovering. They can save everything.
Compare Europe with Australia, which has two thousand endemic species that are threatened with extinction. That's many more than in the whole of Europe, while our economy is tiny compared to the economy of Europe’s, so, in the end, we can't save everything. The situation is worse in most other countries. We've worked out a whole series of approaches and mathematical tools to best allocate the funds and focus them on certain species, because there is a high probability of success, it’s cost-effective and they are important. But then people get very angry because they feel you're playing God. Truth be known, we have no choice, government and non-government funding is still inadequate in most countries to save all species.
Once you said many people dislike you because you tend to hold unpopular views, such as that money is not always used effectively in science. Can you explain why do you think it is ineffective and what should be changed?
I notice a lot of conservation biologists are really ecologists who will, for example, study the genetics of a rare plant that lives in four marshes in the Czech Republic. When I ask why, they will say to know whether population one is genetically distinct from population two, three and four. Tell me how will that change policy and management on the ground? Many times, even they can’t explain that. If there is no pathway their research having an impact on the ground and then it's not conservation science, it’s just more ecology. So, they shouldn't take the money from the conservation science budget.
I often say we don’t need more data to solve a problem, we have enough already. And people don't like that because they want to collect more data and do more science, because some of them just love science. But if you spend all your money in conservation just learning more, you never act. If you spend all your money in conservation just acting, eventually you'll make mistakes. So, there's got to be a balance between knowing more and acting more. The science to solve that problem is called “value of Information theory”.
And what about science communication, which is now more important than ever, is that in your opinion done effectively?
There has been a massive improvement over the last ten or twenty years. In Australia, we had a very influential environmental scientist, Peter Cullen, and he coined the term “knowledge broker”. A knowledge broker is a science communicator who sits in with the scientists and then works out all the different ways their science can be used to impact policy and management. I think that’s the interesting thing about science communication; there's about twenty ways to do it and all people have their preferred ways.
I don't have any theory about what works and what doesn't, I observe spectacular successes and spectacular failures. When somebody first explained Twitter to me, and mobile phones, I thought that they were the most ridiculous things in the world that would never be of any use to anybody. So, in terms of predicting the future of science communication, anything I could say is almost certain to be wrong (laughing).
In the past, you have caused a public outrage with your statement on culling a hugely overpopulated koala population. Speaking of spectacular successes and failures, I want to ask what did you learn from this case in terms of science communication?
Well, I'd probably do the same again, because I have a’ very obsessive-compulsive belief that even if it's unpopular, telling the truth is important. We went through our process, we said the best thing to do is shoot them, it causes less suffering, it's cost-effective and it delivers an outcome. We did convince most people in South Australia that it was a smart thing to do, but the further you moved, the harder it was to explain the complicated human wildlife interactions. The Japanese, Americans and Europeans were outraged. Also, when our committee advised shooting these koalas, I must admit I could not shoot one. Have I learnt anything? I suppose I haven’t.
Why do you think people are so concerned with culling some species, but care very little about culling other?
There's a great paper by Bob Smith about why some animals are more beloved than others. Often, it's just excellent media. I think generally animals who look more like babies, so big eyes, round faces and forward facing eyes. Obviously, not all animals fit that psychology profile, for example, elephants and whales have very small eyes, and they are on the side of their head and people love them. So, it’s also about iconic animals and stories around those animals.
What role do the academics and researchers have in helping environment and conservation?
A lot of it is about raising awareness and speaking truth to power. Many academics forget that they're some of the few people in society that can say what they want without fear of retribution. So, I think it's invaluable that they engage in public debate on issues that they're experts on as much as possible, it is our responsibility. Although, not everybody trusts scientists and academics and universities, I think they are more trusted than many people, because usually they're not profiting from the views they have. Personally, I must say that the whole process of being a public intellectual takes time away from my research, and people yell at me a lot. Because of the koala episode, I received a death threat. But I still think the fact that academics often take on altruistic roles to inform the public regardless of the consequences is a very important part of their duty.
Is it important to have the public involved in conservation? If so, how would you involve it?
Well, there's lots of ways of doing it. The easiest way is through natural history and getting people interested in nature. In Europe, the number of people who are naturalists of some kind is probably five to fifteen percent, so big percentages of the population. But I think the more people get involved in learning and looking about their ecosystem, counting the insects, the birds, and the mammals around them, the more that leads them to worry about things disappearing. So, that's when they start to move from a naturalist to an activist. And effectively that's what I did when I was 17.
For many people, the love of animals starts with a pet, then that changes to love of wild animals and that then becomes the love of habitats and that means people wanting to maintain functional ecosystems because they see they're connected. I'm keen to get more people through that journey. The data now shows that people's mental health is enormously improved by birdsong and green things and views of water. So, the more they know about them, the more they'll fight to defend their ecosystems, either through paying money or talking to government. You can influence your companies that they can use less paper, energy and water. Most people will do what's comfortable for them and that might be planting trees in the park, counting butterflies, or writing letters to politicians. I think that everybody should just do things that they like doing. I'm willing to do anything, to suffer any pain to achieve conservation outcomes.
In October, you attended the ICRI conference in Brno. Do you think that conferences are useful for making progress?
I think they are a way of sharing information face to face. I've been to around 150 conferences in my life. That's five a year, that’s a lot of conferences. And the good thing about them is that you listen to a lot of things you wouldn't normally listen to, you meet a lot of people you wouldn't normally meet. If you're sitting there, and I suppose smartphones have made a mess of this, usually you can't do much but think and listen. I find that many of my best ideas have come from conferences, conversations in the bar, and listening to people's talks. I think all that human interaction is very important. It encourages people to persist.
What do you work on now and what would you like to work on in the future?
In terms of the science and the mathematics, very little. I usually spend most of my time helping students and postdocs, writing them references to get a job. I’m still fighting the very important policy fight on habitat protection. But more and more I'm also trying to do the things I did when I was very young, like going out into nature and count the birds. I'm redoing bird surveys I did in 1981 at the same places in the same way. I'm trying to grow and plant more trees and shrubs. Basically, I think my task now is largely about assisting everybody else to achieve what they need to achieve.