Episode 65      30 min 53 sec
Effects of Climate Change on Biodiversity

Prof Ary Hoffmann and Dr Michael Kearney discuss the effects of climate change on biodiversity, and how our quality of life could be adversely affected. With host Shane Huntington.

"In a sense biodiversity, or a loss of biodiversity, can actually threaten our food supply." - Prof Ary Hoffmann




           



Prof Ary Hoffmann
Prof Ary Hoffmann

Prof Ary Hoffmann completed his undergraduate education at the University of Queensland and Monash Universities, graduating with a BSc(Hons) in 1980. He then undertook PhD at La Trobe with Peter Parsons, graduating in 1984. Ary completed a postdoc at UC Davis with Michael Turelli before returning to La Trobe where he started as a Lecturer and attained a personal Chair in 1998. Ary recieved a Federation Fellowship in 2005 to conduct research at the University of Melbourne.

Ary is a Fellow of the Australian Academy of Science

Dr Michael Kearney
Dr Michael Kearney

Dr Michael Kearney completed his undergraduate studies in Botany and Zoology at Monash University where he obtained a BSc(Honours) in 1998. Michael then obtained his PhD in Zoology at the University of Sydney under the guidance of Prof Richard Shine in 2004. This included a one year Fulbright fellowship the USA where he collaborated with Prof Kellar Autumn at Lewis and Clark College in Portland Oregon, and Prof Warren Porter at the University of Wisconsin in Madison, Wisconsin. Dr Kearney then took up an Australian Research Council Postdoctoral Fellow at the Centre for Environmental Stress and Adaptation Research (CESAR) from 2004-2006. Michael joined the Zoology Department as a lecturer in 2007.

Credits

Host: Dr Shane Huntington
Producers: Kelvin Param, Miles Brown and Dr Shane Huntington
Series Creators: Eric van Bemmel and Kelvin Param
Audio Engineer: Miles Brown
Theme Music performed by Sergio Ercole. Mr Ercole is represented by the Musicians' Agency, Faculty of Music
Voiceover: Paul Richiardi
Photos: Les O'Rourke

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The Effects of Climate Change on Biodiversity

VOICEOVER
Welcome to Melbourne University Up Close, a fortnightly podcast of research, personalities and cultural offerings of the University of Melbourne, Australia.  Up Close is available on the web at upclose.unimelb.edu.au.  That’s upclose.unimelb.edu.au.

SHANE HUNTINGTON
Hello, and welcome to Up Close, coming to you from Melbourne University, Australia.  I’m Dr Shane Huntington.  Over the course of the last century, there have been many circumstances in which biodiversity in particular ecosystems has been threatened by human activity.  Forest clearing, over fishing, pesticide usage and industrial pollutants are examples of human activity that have adversely affected numerous species.  In these somewhat contained scenarios, we can determine with relative ease the impact on biodiversity.  Global climate change, in comparison, will have a planet-wide impact on biodiversity, changing weather patterns, the complete removal of ecosystems, intensification of severe conditions, and sea level changes, and the overall changing of entire climatic zones will all contribute to the overall assault on the biodiversity of earth’s ecosystem.
Today on Up Close we are joined by two of Australia’s leaders in biodiversity.  Professor Ary Hoffmann from the Centre of Environmental Stress and Adaptation Research at the Bio21 Institute and the Department of Zoology here at the University of Melbourne, Australia, and Dr Michael Kearney from the Department of Zoology, the University of Melbourne of Australia.  Welcome, gentlemen.

MICHAEL KEARNEY
Thank you.

ARY HOFFMANN
Nice to be here.

SHANE HUNTINGTON
Okay.  I think we should start off by talking a bit about what we mean by biodiversity.  So, Ary, I’ll start with you.  If, for example, the biodiversity of the planet earth was substantially reduced all of a sudden, what would be the effect?  What sort of things would we see happening?

ARY HOFFMANN
Well, obviously if the biodiversity is reduced, we’re going to lose a lot of species, given that biodiversity is often defined in terms of the number of species you have.  So that means that we could potentially lose many species that we consider to have a high value.  So, you know, mountain pygmy possum, I guess, is a local example.  It lives up in the alps, it’s very restricted, and that’s a particular marsupial which is the only hibernating marsupial, could actually disappear completely.  
We could also lose a lot of our iconic plant species and animal species, and on top of that you’re also going to lose a lot of ecosystem processes. So when you lose biodiversity what you can also do is lose the processes that that biodiversity actually provides.  So, for instance, biodiversity in the sense of plants provides a filtering system for our water.  So when you think about the catchments around Melbourne, which is our main water supply, that is filtered water that runs through the vegetation, and if the vegetation starts disappearing or changing in a dramatic way, then that could actually be quite severely affected.
It’s not just water supply.  It’s also things like pest control so, for instance, there are many aspects of our biodiversity that help control the pests that attack our food supply.  So in a sense biodiversity, or a loss of biodiversity, can actually threaten our food supply.

SHANE HUNTINGTON
Michael, let me turn to you for a moment.  In terms of things like disease and how we are affected by it and what things transmit it, will biodiversity increase or diminish our exposure to disease.

MICHAEL KEARNEY
As Ary was saying, we have biodiversity providing us a means of pest control, and so some species like mosquitoes, which transmit disease, may alter in their abundance as interactions between species change as we reduce biodiversity.  When we just reduce biodiversity, what we’re doing is changing a very complex web of interactions of ecological interactions, and that’s going to change the distribution and abundance of different species including those that cause disease.

SHANE HUNTINGTON
Now, I’m going to get onto the specific aspects of climate change soon, but there are no doubt examples in our history, or not necessarily our history;  we’re not old enough;  but in the planet’s history, where this sort of scenario has occurred before.  Can you talk a bit about that, Ary?  I mean, that have been major changes in biodiversity in the planet’s history?

ARY HOFFMANN
Yes, look, I mean, animals and plant species are continually changing distributions over periods of hundreds of thousands of years, and there are dramatic examples of that.  So, for instance, we know that at one stage rainforest was much more widely spread in south-eastern Australia than it is currently, and also up in the tropics.  So you do have those expansions and contractions that are a consequence of changing climates. And at certain times in our past history a lot of our biodiversity actually becomes restricted to refugia areas, you know, which are small areas that might remain damp or warm enough to actually support that form of life.  So, yes, you do have those large cycles going on, but of course what is different about climate change compared to those cycles is the speed at which it actually occurs.
So when you have something happening over hundreds of thousands, or even millions of years, then obviously plants and animals can adapt to a large extent, but when it’s happening over tens of years it’s a very different situation.

MICHAEL KEARNEY
We have had major losses of biodiversity in the past, so you may have heard of the different geological periods, like the Cretaceous Period.  They’re all identified by losses of species in the fossil record.  So the Permian mass extinction, we lost something like 99 per cent of the species that were in the fossil record.  So those are cases of cataclysmic events that did dramatically reduce biodiversity on very long time periods,  millions and millions of years, and the biodiversity then recovers and then we’ll crash again at the next mass extinction event.

SHANE HUNTINGTON
Over the next 20, 50, 100 years, are we expecting something of that magnitude?

MICHAEL KEARNEY
Well, it’s difficult to predict, but one of the best predictions made is that we could potentially lose up to a third of our biodiversity through the process of climate change alone in the next hundred years or so.

SHANE HUNTINGTON
Ary?

ARY HOFFMANN
It really depends on what sort of levels of CO2 in the atmosphere and what sort of levels of temperature change we’re talking about.  I mean, those predictions depend very much on what we consider to be the [equivalent] value that we can actually get to.  Certainly based on current trends we are looking at, as Michael said, a third, and probably a lot higher than that in many situations, in terms of loss over a period of 50 to 100 years.

SHANE HUNTINGTON
We often hear these numbers of a few degrees over the next century in terms of the average temperature of the planet, but in individual environments, how extreme is that?  Are we talking about 10 degrees. Or is it all much the same?  A couple of degrees here and there?

ARY HOFFMANN
In the Australian context, we’re not just talking about temperature but we’re also talking about rainfall, and it’s actually rainfall that at least from the perspective of plants is likely to have somewhat a bigger impact.  We are talking about a few degrees, so hopefully we can stabilise it at two to three degrees. But there are many people that think that we’re already in a situation where five degrees might be unavoidable in 100 years’ time.  So that’s an awful lot, and that means that from a thermal point of view, you’re going to fall outside the tolerance limits of a lot of species.  But again it’s the extremes that are often quite important as well.  So just because average temperature is changing by a few degrees, it might actually be a case that extremes are going to change a lot more, and that certainly is the prediction of a lot of climate models, and those extreme effects and events can have a major impact on the biology of a system.
You’ve only got to think about the heat wave that was recently in Melbourne, where we had the highest temperature being exceeded in Melbourne, and it’s only a short period but that had a massive impact in terms of leading to a large amount of animal death and plant death as well.

SHANE HUNTINGTON:
You’re listening to Melbourne University Up Close.  I’m Dr Shane Huntington and today we’re speaking with Professor Ary Hoffmann and Dr Michael Kearney about biodiversity.  
Gentlemen, I assume there are a number of scenarios over our history of, say, the last 100 years where species have responded to changes caused by humans to their environment.  Can you give me a couple of examples, Ary, of where that’s occurred and where species have evolved to deal with our impact?

ARY HOFFMANN
Yes, absolutely.  There are many well documented cases where species have evolved.  Firstly, of course, what species can do is actually change their distributions.  They don’t necessarily have to evolve to deal with climate change, and certainly in the context of recent climate change over the last few decades we have a number of species that are actually shifting their distribution.  Now, evolutionary changes can also happen, and certainly some of the best examples of evolution in action, or rapid evolution in action, come from human-related stressors.  So, for instance, we can think about insects evolving resistance to pesticides.  We can think about weeds evolving resistance to herbicides.  Those are all very rapid evolutionary changes.
Now, also in the context of recent climate change, we are starting to see some animals actually adapt, and also some plants.  So, for instances, we’ve had situations where weedy species have evolved their flowering time in response to aridity, so if things have got drier, basically some species seem to be shifting their flowering time to flower early, and those are genetically based changes that are actually examples of evolution.  We also have situations where certain insects are changing the way they respond to seasons, so if the season is becoming more favourable because winter is arriving later, what some insects are actually doing is staying around longer to reproduce, and that means that they can actually take advantage of the warmer conditions, and that again is a evolutionary shift.

SHANE HUNTINGTON
I understand one of the big challenges at the moment is determining the vulnerability of particular species to these changes, and I’m sure our listeners will appreciate that determining vulnerability for even one species is an incredibly complex scenario because of all the things that affect it, and my understanding is these fall into two distinct categories, one being intrinsic categories and one being extrinsic categories.  So I’d like to separate those two for a moment and talk about them individually.  Ary, can you give us an idea or a feel for what we mean by an intrinsic factor?

ARY HOFFMANN
When we talk about intrinsic vulnerability, we’re talking about the characteristics that a species possesses that actually allow us to deal with particular stressful conditions, and they fall into two categories, I guess.  On the one hand you’ve got your genetic make-ups, so in other words particular genes allow you to cope with different types of conditions, and we all know that different plants and different animals have different susceptibilities to climatic stressors, so that’s an example of a genetically programmed response.
On the other hand, you can also mount what’s called a plastic response.  So in other words, if you’re exposed to a fairly warm condition, you can then become more resistant to dealing with a heat wave when it comes along.  On the other side of the coin, if you’re exposed to a cold condition, you can actually deal with cooler conditions because you become acclimated to those conditions.  
The other thing that animals and plants are very good at doing is to go into hiding, so you can go into hibernation and avoid extremes in that way, or if you’re a plant you can produce a seed that’s highly resistant at a particular stage, and if you’re an animal you can also produce an egg stage that’s highly resistant to desiccation or to heat, and that happens all the time.  So seasonally animals and plants deal with changing conditions in those ways, and that provides a certain amount of intrinsic resistance to those sorts of changes.

SHANE HUNTINGTON
When you look at some of these factors, do you find that species that live in harsher conditions or more severe conditions have a sensitivity level that may give them an advantage in these climatic shifts?

ARY HOFFMANN
Yes, and it’s interesting.  Michael mentioned the fossil record and the fact that we’ve had these sorts of dramatic changes in biodiversity. And it turns out that when you look at those, different groups suffer different levels of extinction.  So, in other words, the groups that consist of organisms where they do have resistance tend to do a bit better than other organisms in terms of avoiding extinction.  So in that sense they really do seem to actually have some intrinsic level of resistance to even surviving mass extinction events.

SHANE HUNTINGTON
Michael, I want to get your take here on this, and I think maybe through a particular example regarding thermal tolerance.  I understand you’ve been studying certain species where thermal tolerance is incredibly important to their propagation.

MICHAEL KEARNEY
Yes.  Temperature is an important issue for every species on the planet, and temperature affects different kinds of animals in different ways.  So we can get a clue about what aspects of the animal to look at based on what kind of animal it is.  If we’re talking about what we call an ectotherm, most organisms on the planet are ectotherms, their body temperature depends on the environment that they find themselves in.  So, for instance, a cane toad would be an example of an ectotherm.
So a cane toad’s temperature depends on the air temperature around it, but also it’s got wet skin so it’s actually losing water through its skin, and that’s cooling it down a little.  So we want to be able to predict what temperature the cane toad is at, and we also want to know how sensitive the cane toad is to different temperatures, and we can get an idea about animals’ sensitivity to different body temperatures by changing their temperature and then making them do something.
So, for instance, with an animal like a cane toad or a lizard, we can actually change the temperature of the animal and then run it down a race track and see how fast it can run, and that it highly sensitive to temperature.  A cane toad, for instance, has trouble moving at all if temperatures get below about 15 degrees, and yet at 30 degrees they can race along at about two kilometres per hour.

SHANE HUNTINGTON
So this is the reason why cane toads, loved here in Australia we could jokingly say, have not spread across the entire continent.  They’re restricted to a very specific part of the northern aspects of our continent.

MICHAEL KEARNEY
That’s right, yes.  They are relatively at the high temperature end of sensitivity, and they like it to be warm, and there’s a link between the humidity and their temperature too, so in southern areas the humidity cools them down.  If you’re thinking about a cane toad, it also has an aquatic part of its life cycle, so it has a tadpole phase which requires water to breed in.  So knowing a bit about the biology of the animal, knowing it’s a frog, you know that there’s going to be some temperature sensitivity and there’s also going to be a requirement for water, and so you can bring those sorts of characteristics into your prediction.

SHANE HUNTINGTON
What about things like population size, Ary?  How does the size of a population affect its sensitivity to these shifts, and if you had a scenario where, for example, you were geographically restricted on an island or something, what does that do to the vulnerability of these species?

ARY HOFFMANN
In general the rule is that the smaller the population, the more vulnerable you actually are, and that really relates to how much genetic variation you have to allow you to actually evolve.  So if you have a large population size, it means – a bit like humans, for instance;  we’re obviously a very large population;  you have many different forms of genes and some of those genes might allow you to deal with temperature stress better than other forms.
So when a temperature stress comes along and you’ve got a population of a large size, then the forms that actually allow you to deal with temperature are going to become more abundant over time.  So in a sense that allows you to mount, if you like, an evolutionary response to the change in temperatures.  When you’ve got a small population size, you simply don’t have that variation there, so you can’t mount an evolutionary response as easily as when you’ve got a large population size.
Now on top of that you’ve also got this issue of how restricted you are.  If you’re stuck on an island, you actually can’t really move, of course, which means that if conditions change then you have to adapt a lot more quickly because you can’t get out of the way of a particular stress.  So island populations are particularly vulnerable, not just because of population size but also because of where they are.  They’re sort of stuck in an area where the environment around you is incredibly hostile.

SHANE HUNTINGTON
I guess this comes to the point of resilience of a given species and aspects like the reproduction rate and the actual life history of that species.  I assume these also have a major impact on just how vulnerable they are to change.

ARY HOFFMANN
Yes, they certainly do.  I mean, if you’re producing an awful lot of offspring every year, then you’re generally more resistant than if you’re only producing a few every few years.  So basically if you have a life history that means that you have a high rate at which you pump out things, and also that you have a life history that often allows you to extend a certain period of time, so you don’t die every year, for instance, you tend to be a bit more resilient to short term changes in climate for those reasons.

SHANE HUNTINGTON
In the past, whenever we’ve talked about animals that have had a particularly large free range, so elephants, a lot of the larger mammals in particular, we’ve often seen this as something that human activity has encroached upon and had a very negative effect on their lives and their populations.  When it comes to climate change, does having a large range over which you roam give you an advantage?

ARY HOFFMANN
Let’s think about an Australian example.  So we have migratory birds, for instance, in Australia.  When you’re a migratory individual, what you have to do as you migrate is to pick up food all the way along.  So what can happen there is when you have these long distance migrations, you have to make sure that you can provide all the resources along the way to allow you to do those long distance migrations.  Any effect along the way means that that species then becomes vulnerable.  So if, for instance, you’re destroying the habitat of a bird population and it’s important habitat like a wetlands that they require to rest, if you like, during the migratory period, then effectively you’re destroying that migration route which, of course, potentially can lead to extinction of that series.  So long distance migration can make you more susceptible to climate change. Now, if you have a species that is widely distributed geographically and that is not specifically migrating, then it does become more resistant to climate change, simply because of the fact that there will be some populations that will be in moist areas;  some populations that will be in very dry areas;  which means that the entire distribution of that species encompasses a range of climate zones.  
So if you think about the east coast of Australia, we have insects, for instance, that occur all the way from the tropics down to temperate areas.  They’re going to be pretty resistant to climate change.  On the other hand, if you’re actually stuck on a mountain top somewhere in the tropics you’re going to be very susceptible to climate change.  So widespread does mean more resilience, but widespread and a very strict migration route actually makes you more susceptible.

SHANE HUNTINGTON
You’re listening to Melbourne University Up Close.  I’m Dr Shane Huntington and we’re speaking with Professor Ary Hoffmann and Dr Michael Kearney on biodiversity. Let’s move now to the extrinsic issues, the issues coming from outside the species themselves.  I’m guessing the level of exposure that a certain species has is probably the most important element of determining this risk factor for their vulnerability.  Ary, can you say something about that?

ARY HOFFMANN
Yes.  I mean, if you’ve had a species that’s had a long history of being exposed, for instance, to fluctuating conditions or very dry and very hot conditions, it’s going to be more resistant to those sorts of changes.  On the other hand, if you have a species that lives in a very narrow climate zone, a very narrow range of climates, it’s going to be more susceptible to any change that’s actually going to occur.  So our weedy species tend to be quite resistant to climate change because they’re often exposed to a range of different conditions, whereas species that we have in the rainforests are actually generally much more susceptible to different types of climate stress.
So, for instance, we’ve been doing work on Drosophila which is a vinegar fly, and the majority of biodiversity actually occurs in rainforests, these rainforests in North Queensland in particular, and all those species tend to be incredibly susceptible to desiccation, and they also tend to be incredibly susceptible to cold conditions.  So as soon as it gets too cold or too dry, they basically die out.
On the other hand, if you look at species that have a much broader distribution, so for instance we have vinegar flies that are associated with humans up and down the east coast and the west coast of Australia and pretty much around the world, and those sorts of species tend to be very resistant to climate stress.  Be it drier conditions or warmer conditions or colder conditions, they just seem to be able to deal with the extremes to a greater extent, and that probably really reflects the evolutionary history of those species.
So species that tend to have an evolutionary history of being exposed to a range of conditions tend to be more resistant, whereas species that tend to have an evolutionary history of being in a confined environment tend to be much more susceptible to those stresses.

SHANE HUNTINGTON
Ary, what do we mean by the term microhabitat buffering?

ARY HOFFMANN
What microhabitat buffering is, is basically a situation where an environment might change and the ambient conditions in that environment might change, but you’ve got somewhere to hide out, so you can actually buffer the conditions you’re exposed to by hiding out in a particular spot.  So, for instance, the mountain pygmy possum example I mentioned earlier, they actually live in boulder fields, so there are these massive boulders that are stacked on top of one another on the top of the alps in Victoria, and what those animals they can do is they can experience quite different temperatures to the ambient conditions by hiding out amongst those boulders.

SHANE HUNTINGTON
Mike, was microhabitat buffering a short term solution for these species?  Does it generally end badly?

MICHAEL KEARNEY
All animals are using microhabitat buffering to some extent.  So when we think about climate, we’re thinking about what’s measured in a weather station, and that’s the air temperature at two metres.  Animals actually seek out micro climates within their habitat, and when we’re thinking about climate and microhabitats, we’re thinking about micro climates.  So different animals will use different kinds of micro climates to buffer themselves against a change in the environment around them.  Lizards, for instance, you see the lizards doing this all the time.  They choose shade in their environment to cool themselves down if it’s getting too hot, and if it’s a cool environment they’ll move out of the shade and into the sun.
So this is a link between the habitat and the animal, and the animal’s sensitivity.  So an animal might have quite a narrow sensitivity.  When you race them down the race track there’s only a very narrow window that’s optimal for them.  But maybe in their habitat they can choose between sun and shade if the habitat allows it, and buffer themselves, and actually make sure that the temperature they’re experiencing stays very close to what they want to be at.  If we change habitats through land clearance or change fire frequency or increase shade in some cases, we’re going to alter the ability of animals to buffer themselves in microhabitats.

SHANE HUNTINGTON
Michael, you’ve already given us a couple of beautiful examples but I know you have another couple to share.  One is that of the great glider which is one, I understand, of the largest possums here in Australia.  Tell us a bit about that particular possum and why there’s interest there.

MICHAEL KEARNEY
The greater glider is an amazing possum that you get down the east coast of Australia, and it’s our largest gliding possum.  We’ve talked a lot about ectotherm so far but it’s, like us, an example of an endotherm.  So it can produce its own internal heat to keep itself warm if it’s in a cold environment, but when it gets hot it can also control its temperature by losing water.  So a greater glider requires a particular kind of retreat site.  It requires a tree hollow to live in.  The reason it needs a tree hollow is to help buffer itself against extreme environment conditions.  It’s actually very sensitive to high temperature, so if you put a greater glider in a room that’s about 30 degrees, they’re starting to get heat stressed and they’re starting to pant, lick their fur and lose a whole lot of water.
So for an endotherm, for a mammal or a bird, if it gets cold it costs it energy to be cold.  If it’s hot, it costs it water to cool down.  We’ve seen a lot of endotherms in trouble, a lot of bats and ringtail possums in Melbourne recently when we had the heat wave on Black Saturday, a lot of animals died because they just weren’t able to use their evaporative cooling to keep themselves from rising up to a dangerous body temperature.

FACILITATOR
Black Saturday refers to an event that occurred here in Melbourne Victoria Australia on February 7, 2009, when extreme bush fire conditions caused the destruction of many towns, the loss of many lives, and the destruction of a large number of ecosystems around the Melbourne and surrounding areas.

MICHAEL KEARNEY
With the greater glider, what we’ve tried to do is ask where could it potentially live by asking how much water would it need in a given environment to actually cool itself down, and how much would it be getting in from the food, because it’s eating eucalypt leaves;  it’s a bit like a koala;  and it really only gets its water from those leaves, so we know the content of water in a leaf, and so we can say in these places it’s going to need more water than it actually gets from its leaves to survive, and therefore can’t live in those places.  Then we can ask if we change the climate to a climate change scenario, how does that affect the potential range.

SHANE HUNTINGTON
If we move across the ocean for a brief moment to New Zealand, I understand a species there called the tuatara actually has its sex dependent on temperature.

MICHAEL KEARNEY
Yes, tuatara are weird for lots of reasons.  They’re an ancient relic kind of lizard-like creature, not really a lizard but they’re a lizard-like creature that used to be widespread at the time of the dinosaurs and now are restricted to islands off an island in New Zealand.  So they’re only on offshore islands in New Zealand.  Like a number of reptiles, the sex of their babies depends on the temperature the eggs experience while they’re incubating.  They’re kind of unusual among other animals with this kind of phenomenon in that as it gets warmer they just become all male, so above a critical temperature of about 21, 22 degrees at a certain time in incubation, you only get male tuatara coming out of the next.  
The worry is, of course, that if it gets too warm, then there won’t be any girl tuataras, so we’ve been trying to assess whether the tuatara has an ability to buffer itself against climate change by changing how deep it lays its eggs, changing what time of year it lays its eggs, and changing the degree of shading where it lays its eggs, and currently tuatara only lay their eggs in full sun.  If they keep doing that on the islands that they live on, one species in particular, it’s in trouble;  but if it was to choose shade it would completely fix that problem.  We don’t know whether they would actually choose shade but we can easily shade the nests themselves if we need to, as a manipulation.

ARY HOFFMANN
Of course, it would be very strong evolutionary selection for laying your eggs in the shade in that situation, and perhaps the tuatara has genetic variation that might allow it to actually do that.

MICHAEL KEARNEY
Fingers crossed.

SHANE HUNTINGTON
Ary, just to finish up I think we should cover off the issue of how we respond to issues of biodiversity.  Do we currently have the right level of adaptive management capacity to deal with this scenario?  The number of species on this planet is immense.  Do we have that capacity?

ARY HOFFMANN
We’re thinking about it.  We don’t quite have the answers and the right framework yet, but at least we’ve started thinking about it.  So in Victoria, the Victorian government is currently thinking about how do you actually manage biodiversity on the climate change, and it’s a very serious issues because in the last 100 years or so we’ve got used to thinking about it from a very static point of view.  So in effect we’ve a fairly good system of national parks and reserves, and what they do is protect biodiversity in a static way.  So basically you say, oh, well, you know, I’ve got this species and it’s a threatened species and it’s in a national park and that’s okay, as long as I’ve got it in another national park in case one burns down, then at least it will survive in the other one.  
So that’s sort of the way that we’ve approached biodiversity management in the past.  Now what we’re saying is, well, hang on a sec, that national park that that particular species is in is going to be very different in the next few years, and that eucalypt species that that particular species requires to survive may no longer be able to live because the climate is shifted.  So all of a sudden what we realise is, gosh, you know, what we need to do is to actually set up systems that allow species to migrate, because that provides at least some resilience to those species.
Then we have to start connecting things.  So we’ve got a bit of a national park here, a bit of a reserve there, and somehow we need to somehow bring those together to allow movement to actually occur.  The other thing we have to realise is, you know, as you pointed out at the beginning of this interview, climate change has occurred in the past.  It’s been a lot slower, but animals and plants have survived those drastic periods through refugia.  So what we need to do is very quickly identify where those refugia have been in the past because that’s also where they’re likely to be in the future, and we need to put a very strict protection order on those refugia to make sure that our biodiversity at least has somewhere to go back to if things change dramatically.
So we need a very dramatic way of rethinking this whole issue, and of course part of our challenge is that governments come and go every three years and what we’re talking about is planning for a period of 50 years or 100 years, and you need a certain amount of political will to achieve that.  When politicians are obviously concerned about being re-elected, and you can’t blame them for being concerned about that, it’s very hard for them, even if they have the vision, and I think some of our politicians do, but even when they have the vision to try and push that through, to say to the community, “Let’s think long term about these things.  This is a serious business.  We are going to lose a lot of our essential services that we need to live if we don’t do this now.”

MICHAEL KEARNEY
Ary has described some particular things that we need to do in the face of climate change that are directly related to the climate change response itself, but we can also do is just do the basic conservation that we’re doing now better, because species in Australia and around the world are suffering from invasive species, from introduced predators and pests, and from land clearance.  So that we’re going to maximise the ability of animals to buffer themselves against climate change through also just reducing those other stressors that they’re experiencing right now.

SHANE HUNTINGTON
Professor Ary Hoffmann and Dr Michael Kearney, I certainly do not envy you the task ahead but it has been a great pleasure having you on Up Close today.  Thank you very much.

MICHAEL KEARNEY
No problem at all.

ARY HOFFMANN
Thank you, Shane.

SHANE HUNTINGTON
Relevant links, a full transcript and more info on this episode can be found on our website at upclose.unimelb.edu.au.  We also invite you to leave your comments or feedback on this or any episode of Up Close.  Simply click on the Add New Comment link at the bottom of the episode page.  Melbourne University Up Close is brought to you by the Marketing and Communications Division in association with Asia Institute of the University of Melbourne, Australia.  Our producers for this episode were Kelvin Param and Miles Brown.  Audio recording by Russell Evans.  Theme music performed by Sergio Ercole.  Melbourne University Up Close is created by Eric van Bemmel and Kelvin Param.  I’m Dr Shane Huntington.  Until next time, goodbye.

VOICEOVER
You’ve been listening to Melbourne University Up Close, a fortnightly podcast of research, personalities and cultural offerings of the University of Melbourne, Australia.  Up Close is available on the web at upclose.unimelb.edu.au.  That’s upclose.unimelb.edu.au.   Copyright 2009, University of Melbourne.


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