Green Adelaide Podcast
Do you want or have a career in South Australia’s environmental sector? Then this podcast is for you!
Green Adelaide Podcast
Ep 15: RE-RUN w/ Geoff Williams | Platypus Reintroduction to River Torrens + Australian Platypus Conservancy + career in wildlife conservation + platypus + urban adaptability + conservation strategies
You might not know that August is known as Platypus Month.
So to celebrate this iconic Australian creature we’ll be re-running our episode all about platypuses and reintroducing them to metro Adelaide with the fun and knowledgeable Geoff Williams from the Australian Platypus Conservatory.
I’ll be back with a new ep for the pod next month!
This episode we’ll be diving deep into the details of re-introducing platypus to an urban area with platypus expert Geoff Williams from the Australian Platypus Conservancy. The Conservancy is a non-profit environmental organisation that was set up in 1994 to conserve the platypus and its freshwater habitats.
The Green Adelaide Podcast is your insider scoop on all things cool, green, and wild in metropolitan South Australia.
We feature the experts, including the leaders and ecologists to the planners and marketers to chat the people, projects, and news of SA that you, our enviro-listeners, must know about.
I’m your host Melissa Martin and I’m the Communication Manager at Green Adelaide.
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I was working at the zoos, for example. I had to become a general manager as well as a biologist, and that brought in a lot of useful skills in terms of knowing how to manage budgets and how to get sponsors and how to get you know, work with the media and all those sorts of things, and that's just as important in a way, as actually you know your environmental skills. And so I would say to people you know, never turn down an opportunity to take on something that's a bit out of the mainstream and certainly never dismiss an opportunity to move to different areas.
Melissa Martin:Hey guys, welcome to the Green Adelaide podcast. I am your host, melissa Martin. You might not know that August is known as Platypus Month, so to celebrate this iconic Australian creature, we'll be rerunning our episode all about platypuses and reintroducing them to metropolitan Adelaide. Platypuses and reintroducing them to metropolitan Adelaide. We are joined on this episode with the fun and knowledgeable Jeff Williams from the Australian Platypus Conservancy. I'll be back with a new ep for the pod next month, so enjoy the show and you will find out everything you didn't know, that you needed to know about platypuses and reintroducing them to Adelaide's River Torrens, katawita Pori.
Melissa Martin:Currently, there's really only one place in South Australia where you can definitely find wild platypuses and that is on Kangaroo Island in Flinders Chase National Park. We at Great Adelaide want to change that and we want to reintroduce platypus to the River Torrens, and it is possible. The river is so much healthier these days. We picked the platypus because they did actually used to live in the Torrens and there is records of them living there in the early 1800s. This episode we'll be diving deep into the details of reintroducing platypus to an urban area with platypus expert Jeff Williams from the Australian Platypus Conservancy. The Conservancy is a non-profit environmental organisation that was set up in 1994 to conserve the platypus and its freshwater habitats. Welcome, geoff.
Geoff Williams:Can you tell us about how you started your career in the environment sector? I studied biology back in England and was basically an ecologist, and therefore what's always interested me, I guess more than anything else, is fieldwork. I mean, I'm essentially, you know, I've spent a lot of my time being an administrative biologist in one sense, but what I really enjoy is fieldwork and getting out there and getting your hands on animals, as it were, in terms of you know them, being able to use that hands-on research to really find out about what the conservation needs are and then channeling those findings into actual action. And that's what has always fascinated me about the whole business of getting involved in environmental management.
Melissa Martin:What I found talking to different people in the environment sector and what's obviously very obvious now is the degree of people needing to move for their job when you're working in the sector and, as you're saying now, you've moved to different places around Australia and, of course, from the UK to Australia, so I guess it's I get the common sentiment that you've got to be open to moving for certain roles in the environment sector.
Geoff Williams:Yeah, very much so.
Geoff Williams:And I would really say to people who are considering a career that I mean in a way, the more you move, the better.
Geoff Williams:I mean one of the things that I think is really important if you're going to work in the environment is to get a range of skills, and I was fairly lucky in that I was exposed not just to biology, but when I was working at the zoos, for example, I had to become a general manager as well as a biologist, and that brought in a lot of useful skills in terms of knowing how to manage budgets and how to get sponsors and how to get you know, work with media and all those sorts of things.
Geoff Williams:And that's just as important in a way as actually your environmental skills. And so I would say to people never turn down an opportunity to take on something that's a bit out of the mainstream and certainly never dismiss an opportunity to move to different areas, because even, for example, even if you take platypus, there's quite a lot of significant differences between the habitats that they use in different parts of the country and even the way they sort of react. I mean, tasmanian platypus actually seem quite different in the way they behave to platypus on the mainland, and so, consequently, your opportunities to expose yourself to those sort of things is a good one, and I think people should always be happy to give that a try.
Melissa Martin:Yeah, good advice. And so you went from Wollongong to university, then Taronga Zoo, and then what was the name of the next?
Geoff Williams:one Healesville, healesville Centre. Yeah, yeah, gazoo. And then what was the name of the next?
Melissa Martin:one Healesville, healesville, yeah, yeah. And after your time at Healesville, then you were one of the creators or establishers of the Australian Platypus Conservancy.
Geoff Williams:From then, we built up a fairly good team at Healesville who were specialising in platypus, and you know it was good to be able to take most of that team into the platypus conservancy and to really branch out and start looking at a wider range of things. At Hillsville, I mean, obviously a lot of the work we were doing was linked to captive management, but once the conservancy was established our focus was really looking at how platypus were doing in the wild and particularly to see how platypus were doing where they were sort of living on the edge. And what I mean by that is in many places platypus were doing fine. I mean, you know, if conditions were good you have platypus in good numbers. But obviously there were many places where habitat quality had declined and platypus numbers had gone down or had even disappeared completely. And so we wanted to find where that point was, where platypus dropped out. And the way we did that in the initial instance was to look at the Yarra River that flows into Melbourne, because we knew in the top of the catchment it's quite good, habitat and numbers were good.
Geoff Williams:When you get to the centre of Melbourne then obviously you don't tend to find platypus at Flinders Street.
Geoff Williams:So consequently we knew there was a point there where platypus were living on the edge, and so we did a lot of survey work to find that point.
Geoff Williams:And then, having found that point, we could then concentrate on the habitat qualities that made it good or bad for platypus and so on, and that was a real step forward. I mean, that was something that had never been done before, and it was the first thing to also establish that platypus are very good habitat indicators. In other words, the better quality the conditions are, the more platypus, and vice versa. And so therefore, although you will occasionally get platypus in fairly crummy conditions and you can't even get them in really, really heavily urbanized environments, you won't get them in the same numbers per kilometer as you will in high quality habitats, and that's the real key to understanding platypus populations in high-quality habitats. And that's the real key to understanding platypus populations. You've got to look at the overall catchment, make a decision about the overall quality of it and therefore, can it support platypus? And this is going to be one of the key issues about can we get a platypus population re-established in the torrents?
Melissa Martin:And what do you wish you would have known before you started your career?
Geoff Williams:Well, I guess a couple of things really.
Geoff Williams:I guess one of them is I guess I would have liked to have known how good I was doing at nocturnal field work.
Geoff Williams:If you take on platypus, you spend a lot of sleepless nights, and I'm not naturally a night owl, and so, having done 500 or so sleepless nights chasing platypus, perhaps you would have reconsidered that decision.
Geoff Williams:I think the other thing, though, is probably recognizing what you enjoy doing most in the field of environmental work. Doing most in the field of environmental work, and I'll be honest and say, while I think I'm a pretty good manager and things like that, what I actually do is I'm a very physical, hands-on person, and if you're that, then you know, make certain that you get involved in environmental work. That is going to give you a lot of field work or a lot of practical, hands-on skills. On the other hand, if you're the sort of person who likes being analytical and likes working on computer modelling and things like that, fine, but try and find those out, and I think I sort of learned it the hard way in some respects, and I spent a lot of time behind an office desk when I would have been happier out in the field, and that's what's been great about the Plutipus Conservancy Yep.
Melissa Martin:Great. So I'm not sure if you listen to our other podcasts, but one of the things we do to get to know our special guests differently is a bit of a rapid fire round, so it's to take you out of, I guess, the topics that we're going to talk about. I just fire at you random questions and just say the first thing that comes to mind. So I'm going to give you 10 questions and they're pretty much this or that or your favorite things as the answer, and, yeah, we'll kick it off. So to start off what has been your favourite age so far, I think the 50s.
Geoff Williams:When I was in my 50s, I mean, I was doing a lot of field work and also having, I think, the most maximum impact of using my experience and knowledge to good effect, and probably also was it my most confident in my ability to do a whole range of things, and so I think that having that maturity is good.
Melissa Martin:And what is your go-to lazy dinner?
Geoff Williams:I'm hopeless. I'll be honest and say I love fish and chips. That's I'm quite happy. Do you like fish? Yep.
Melissa Martin:What is your favourite thing to do in the summertime?
Geoff Williams:Basically go for walks in the bush. Look, I enjoy just being in a natural environment and getting out and seeing the country.
Melissa Martin:yeah, how often do you floss?
Geoff Williams:Not as much as I should. My dentist is always telling me I should do it more.
Melissa Martin:What's one of your nicknames?
Geoff Williams:Well, I shouldn't tell people this. I always used to be called Il capo or il mafioso tell us the context so well. I, just when I was, when I was in you know management issues and so on, I guess, um, I I was considered a fairly hard-ass person to work for in terms of getting things done. Yeah, I did my fairly high standards to get work. I get results and I think you know, I think there was a few bodies buried in the backyard who complained about that, I think.
Melissa Martin:And on that same thing kind of if you had to change your first name, what would you change it to?
Geoff Williams:That's a good one. Ridiculously, I would actually choose William, but you can't really have William Williams because I actually like Bill as a name and that's consequently why it doesn't really have William Williams, because I actually like Bill as a name and that's so consequent Bill Williams. It doesn't work as William.
Melissa Martin:And what's your favorite movie of all time?
Geoff Williams:Of all time, I think. Probably it makes me sound ancient, but I actually think Gone with the Wind is the most classic movie of moviedom, if you know what I mean, because it would seem dated now, but of its time. I think it was a superb example of how films should and were made in the old days.
Melissa Martin:And what dish do you cook best?
Geoff Williams:Spaghetti bolognese is about the only thing I can cook.
Melissa Martin:And do you have a hidden talent?
Geoff Williams:I'm very good at digging holes in the ground. We live in a place where we live in the old mining district in central Victoria and it's really rock hard and if you want to plant trees trees you've got to be really good at digging holes.
Melissa Martin:so and can you describe your fashion style in one word op shop, nice, nice, that is. That is our rapid fire round, thank you. So for our next topic we're going to dive into all about platypus and just all the fun facts that everyone must know about them. So our listeners might not know, but the platypus was once native in the River Torrens and the records of platypus living there in the the records of platypus living there in the early 1800s. And now they're a missing, vital part of the ecosystem and platypuses have been considered extinct on mainland South Australia since the 1970s.
Melissa Martin:There are platypus on KI, though Today platypuses are listed as threatened species in Australia and are endangered in South Australia. So, jeff, can you help demystify the platypus for our listeners, because many probably haven't seen them in the wild before, probably not in South Australia either. So we all know they have a bill like a duck, a tail like a beaver, they lay eggs, they have otter-like fur and they have webbed feet. But have researchers been able to narrow down to really understand where these species actually evolved from? So what are their roots?
Geoff Williams:Well, they're definitely one of the key examples of reptiles evolving into mammals. It's believed that round about, you know it's still even unclear about how long ago, but perhaps 140, 120 million years ago reptiles started. Some reptiles started developing mammalian traits and that happened over many, many different examples in different ways, and it's believed the platypus and the echidnas are really one of the can be traced back to one of the first versions of that because they are egg-laying. So in other words, as reptiles were evolved, they maintained this egg-laying thing and then other, obviously other attempts of reptiles to evolve into mammals resulted in marsupials and eutherians like us who have placentas and so on. So they trace their ancestry back a long, long, long way. Now we don't know too much about that journey because the fossil record is very, very patchy so we can't say exactly what the lineage is. But clearly that eagle-laying mammalian you know unusual type of mammal suggests that it was one of the earliest goes at this process.
Melissa Martin:And is there only one type of platypus like the echidna? There's different subspecies of that, Like in South Australia there's the KI1 compared to the mainland one. Is there different subspecies? And I guess another difference that comes to mind is Tasmania they're bigger there, the size of the platypus is bigger. So I guess, is there subspecies?
Geoff Williams:Yeah, at this point in time, no, there are no recognised subspecies of platypus. I mean, there has been a strong case made for Tasmanian ones to be a subspecies, based on the fact that Tasmanian ones are bigger and tend to have some sort of behavioural differences of perhaps being a lot more terrestrial, they come out on land much more and seem much more diurnal. But I think that's just a behavioural issue and not an evolutionary issue. And the size thing in itself is not, again, diagnostic of a subspecies. Basically, the size varies as you go northwards. With platypus they become smaller.
Geoff Williams:So the Queensland ones are very small compared to Tasmania, but that's very similar to the situation with koypus they become smaller. So the Queensland ones are very small compared to Tasmania, but that's very similar to the situation with koalas. It's really just a reflection that it's mainly a reaction to climatic conditions. In other words, you need big animals to do better in cold conditions and vice versa. So at this stage there's been quite a lot of genetic analysis now over the last 10, 20 years and there is nothing really that supports the idea of subspecies. There are some, I think three sort of distinctive groupings genetically, but they have not yet satisfied the criteria for being separate species. So no, at this stage they're all considered one. It's possible there's still a lot more work to be done on this, and there is some. I always think Queensland ones look very different to the rest of the country, but that hasn't yet been, you know, finalised. Yep.
Melissa Martin:And I know they because they're semi-aquatic, so they're in the water and they're on land. Are they the same speed in both? Or are they fast swimmers, slow on land, or I guess? How fast are they?
Geoff Williams:Well, it's always a bit difficult to say how fast is an animal because it depends what it's doing at the time. Basically, what's been found with the platypus is it's probably optimum speed in the water is about one and a half kilometres an hour, but if they want to, they can go much faster than that. I mean, over short distances they can do the equivalent of an aquatic sprint. And certainly sometimes I remember one occasion when we were radio tracking a platypus that really decided it was going to go off and travel upstream to find a feeding place. You know we couldn't keep up with it, I mean, you know, I mean it's over an hour. It was motoring along at probably four or five kilometres an hour. So they can go faster if necessary.
Geoff Williams:And it's a similar thing on land. They don't come out and walk around on land very much, although the ones in Tassie tend to a bit more. If they want to move fast they can scuttle quite quickly. They're a bit unusual in that. Again, one of the things that traces back to their reptilian ancestors is that they have a shoulder structure that's the same as a lizard and therefore their arms sort of stick out at right angles, as opposed to most mammals that have their legs underneath them, so they're not very good at walking. They sort of shuffle more than walk, but, having said that, they can really put on a bit of speed if they have to. So it's never been properly measured, but they're by no means you know slouches when it comes to mobility.
Melissa Martin:When they're on land. Is there a reason that they are not hanging out in the water Like is it to find different food source or something else?
Geoff Williams:On the mainland. It's mainly a case of you get platypus on land, almost totally related to the time when juveniles disperse. There comes a point when young platypus get basically kicked out of the house and home. It's like when we get sick and tired of our teenagers and say, right off, you go to uni or whatever Something. I mean the adults don't want competition from the young ones. They have to go off and find territories of their own.
Geoff Williams:They travel quite long distances sometimes, and part of that is that they sometimes go on land trying to find either their way over to a different catchment or just because they get disorientated and whatever, and so that's the main reason you'll find platypus on land. They don't search for food on land because their build doesn't work, and so consequently, it's nearly all to do with dispersal movement. Now, the exception to that in Tassie they will come out on land much more, and we think this probably reflects the fact that this is basically suggests that platypus on the mainland probably used to do this much more as well, but have been under pressure now for a long time from things like foxes, and so consequently, there has been selection for platypus that don't come out and walk around on land very much On Tassie. They do come out on land for a whole suite of reasons that don't seem to exist with the mainland ones, and they will wander quite a long distance away from the water to take shortcuts around bends and things like this. So yeah, so that's the main reason they're terrestrial.
Melissa Martin:And kind of a two-part question. Are platypus found in all the states and territories around Australia?
Geoff Williams:No, platypus are only found on the eastern side basically. So their strongholds are really the states of Tasmania, victoria, new South Wales, act and Queensland. In South Australia, as we know, they're found on Kangaroo Island and the only other place they are sometimes found is there is a little bit of the Glenelg River that, for some obscure reason, about three kilometres of it are in South Australia. So you will get platypus that are crossing the border down there and, of course, in the Murray. You know they used to occur in the Murray system quite far down. Now we're occasionally getting reports of them starting to be seen on the South Australian side of the Murray border. So that's again where you sometimes get them. And then the only other place we know there might be platypus is obviously there were platypus introduced in Wurrung Sanctuary in the Adelaide Hills back in the 80s and it's believed that some of those perhaps escaped from the sanctuary and have established themselves around Wurrung. Now that's something which needs a lot more research to actually confirm that.
Melissa Martin:The other part of that question was through your experience working across the country with platypus what are the best places to see them? And I guess they're renowned to being hard to spot, especially during the day, and people wait around and they get like, oh where are they? It's so hard to spot them. So where would you suggest is one of the best spots to see them?
Geoff Williams:All right. Well, let me deal first with the fact about. You know, are platypus hard to spot? And there is a bit of a myth about this, look, I mean there is firstly the myth that platypus are nocturnal, so you don't see them during the day, and that we now know is not true. I mean, all of the studies that have been done suggest that platypus can be out 24 hours a day. They are predominantly nocturnal, but certainly there are times of the year when they'll be out much more during the day and you can potentially see them at any time. So it's always worth having a look. The second thing is there's this myth that platypus are shy and sensitive and, oh, you know you can't see them because they'll disappear the minute you look at them. Again, it's not true. If you're prepared to be patient and quiet and still, you have a very good chance of spotting them, and once you know what you're looking for, they're not hard at all.
Geoff Williams:In terms of places where you can see platypus easily, well, tasmania is undoubtedly the best place. You know most of the rivers in Tasmania, apart from one or two exceptions, have got pretty good platypus populations. So there are places in Tassie where you can go and you know I've been in places where you know in five minutes you can see five or six platypus. I mean, it's not hard, and even in Hobart Rivulet, which is a tiny river that flows in the centre of Hobart, you can see platypus there quite easily. So Tassie is definitely the place.
Melissa Martin:Do you have an understanding of the population of platypus, like numbers-wise in Australia overall, seeing as they are an endangered species?
Geoff Williams:No, look, it's really. There's been various attempts to estimate the number of platypus, and the best estimate at the University of New South Wales coming up was something between 30,000 and 300,000. You know, that's a fairly wide spectrum. It's very hard to say. What I always say is look, I mean, you can't. It's not even really a relevant question.
Geoff Williams:The question with platypus is always how is a population doing within a particular catchment or river system?
Geoff Williams:Because, basically, while platypus can cross land, they do it with great difficulty, and so, consequently, each platypus population is really got to be looked at in the context of its local catchment, and you therefore need to look at the number of platypus that will be supported by the quality of habitat in that catchment, and by that I mean there will be great variation.
Geoff Williams:If you've got good quality habitat, you might have as many as five, six platypus per kilometre. Where you go downstream and start to get into poor quality habitat and you get to very highly disturbed habitats, you may only have one or two platypus per kilometre and then zero. So you've got to weigh that up and make an assessment, and that's why, when we look at the Torrens River, that's going to be one of the key issues is you need to do that sum of saying what's the total number of kilometres in the Torrens that can support platypus, and how many per kilometre, based on the habitat quality, can we ideally get in there, and does that then add up to a number that is going to be a viable population in the long run?
Melissa Martin:Can platypus glow in the dark?
Geoff Williams:Look, this is a bit of a beat up in a way. Look, they did a study in an American museum where they looked at a couple of things to start with, like possums sorry opossums, american possums that they found glowed in the dark when you show it, sean, I think. And they had a platypus in their collection and they did it with platypus and found that glowed in the dark as well. But the reality is, almost everything glows in the dark if you shine the right lights on it. And that includes people you know. If you ever go to a certain type of nightclubs or discos, you'll notice a lot of people, their teeth start to gleam, all right.
Melissa Martin:So now we will dive a bit more into platypus in an urban area and more talking about Adelaide's urban area. So the River Torrens. So Geoff with your work with Green Adelaide and our plan ahead around platypus. What are your thoughts on them? Living a good life in an urban setting compared to like a conservation area or national park?
Geoff Williams:Look, I guess it comes down to the fact that I mean, as long as their basic requirements are being met in terms of, particularly, their food. Look, I mean it comes down to this there are plenty of examples of platypus living in urban environments, and so in Melbourne, for example, they occur within 10 kilometres of the city centre, so they're well within the main suburban area of metropolitan Melbourne, and that is true of many other fairly biggish regional towns throughout Australia. There is nothing fundamentally about living in an urban area that platypus can't adapt to. They are a quite adaptable species. They are not shy and sensitive. They're actually quite tough little animals, really, and as long as there is enough food there and as long as there is enough, you know, of the other things they need they will do fine.
Geoff Williams:I mean, basically, an urban platypus is probably just at home in an urban area as a rural platypus is at home in a natural environment. You know they are not by themselves. You know they become adaptive. You know they are a flexible species. They're quite smart little animals and there is nothing fundamentally about an urban environment that really scares them. You know. I mean, they adapt to the lights, they adapt to the noise and you know we've had platypus living right next to you know noisy highways and things like that. Fine, that's them. You know it's like, say, humans. I mean, you know there are humans who live well in cities and there are humans who live well in the country and it's exactly the same thing.
Melissa Martin:Yeah, it's actually a really good point. So obviously people do think that platypus are like to hide and be hidden and be really shy. So that's a good point that they can adapt and they're not shy as a creature that we keep assuming they are shy as a creature that we keep assuming they are.
Geoff Williams:Yeah, look, I mean, this is a real myth. I mean you know, platypus are, you know, quite inquisitive animals. When I first started studying platypus, I mean you know a lot of, for example, anglers used to tell me oh, you know, I was standing in a river and a platypus come over and swam up to me and swam around my legs and checked me out and I used to think, oh, another fisherman's tile. But it's true, I mean I've seen it happen. And platypus, you know, I've been out. For example, you know, sometimes you're standing in a creek and next thing you know you've got a platypus right next to you. And so, no, they are not shy and sensitive.
Melissa Martin:And so we know in South Australia platypus do exist on KI and there's lots of feral cats there and in the southeast of the country as well. There's foxes there and there's platypus too. Have you seen platypus manage predators like cats and foxes? Like you mentioned that, maybe they don't spend as much time on land if they know lots of foxes around? Yeah, how have you seen the manager and do you think it's a big concern in metropolitan Adelaide?
Geoff Williams:Yeah, look, I think the problem with foxes more than anything else.
Geoff Williams:Look, I think cats and domestic dogs to a certain extent will occasionally take butterflies.
Geoff Williams:I don't think it happens enough to be of any significance, but foxes certainly can take a proportion of the population and make dents in it, and it's particularly true they take juvenile platypus. Juvenile platypus, when they first come out, are very naive animals. They are not particularly good at swimming. They're not particularly good at knowing when to avoid danger. They paddle around in the shallows, and that's exactly where foxes can get down and take them, and so we know numerous examples where foxes have wiped out a lot of juveniles in a particular season, and so it is an issue, and even in urban areas, foxes can tend to be a big problem. Foxes are much more found in urban areas than they are in rural areas in some instances, and so consequently, it is something that can be a problem. I think there's less evidence they have an impact on adult platypus, and so if you can get your adult populations established, you can sort of overcome that threat, but it is nevertheless a significant one, and you can't close your eyes to that fact.
Melissa Martin:How have you seen, because I guess foxes are all around metropolitan areas across Australia how have you seen other states manage that?
Geoff Williams:You can't Look. I mean the reality is look. I mean there are all sorts of theories about how you can control fox populations and so on, and, being honest, none of them have been successful so far and we're a long, long, long way from eradicating foxes eradicating foxes, I mean. So I think the reality is that we need to try to make our environments difficult for foxes. In other words, I think what we should be trying to work towards is ensuring our native species have got enough refuge habitat where they can hide from foxes, so that it becomes less of an issue. And I think, if we're looking at platypus, for example, I mean one of the obvious things that we recommend to management agencies is where you've got shallow areas, you make certain you have dense vegetation buffers planted along the banks at that point. In other words, you just make it more difficult for foxes to get down to the water level, because I don't think they have the capacity to easily catch platypus in deep water, but in shallow water, that's where they can easily pick off.
Melissa Martin:Now we're going to go over to water rats, so ricali and there is lots of ricali in the Torrens and other rivers across metropolitan Adelaide and, as you know, they always get confused with platypus and people think they're seeing a platypus but really it's just a native water otter or water rat, whatever you want to call them. So they're really a super cute creature and I guess we don't want to jeopardize their population if we were to reintroduce platypus to the River Torrens. So, with their strong population today and I guess this happens in other states as well when they've reintroduced platypus to an area, how have you seen that balancing act happen, I guess, between Reucaly and platypus living together? Have you seen any significant changes? The two species?
Geoff Williams:occurred in many, many places together. I mean, you know they're not incompatible. Having said that, there is a degree of competition between them. They both will feed on aquatic invertebrates, but the difference is that the platypus feeds almost exclusively on aquatic bugs, whereas the ricale has got the capacity to eat a lot of other things as well. So small fish, for example, platypus can manage small fish, but they're not good at it. They don't have teeth so they really have to gum fish to death.
Geoff Williams:But ricali are very good at catching fish and catch quite big fish. And they will also eat a wide range of other things as well. And the other big difference between them is that ricali can come out on land and forage quite successfully. So, in very simple terms, ricali have done very well in urban environments because they've got this extra capacity to go scavenging and picking up scraps of food all over the place. And that's why, you know, in the old days in Adelaide I mean, they were particularly found, for example, round about the abattoir areas because there was lots of food scraps getting in the water and on the land they could take advantage of. So the picture therefore that you have, that we have from the studies we've done, if you've got fairly pristine habitats, platypus will tend to predominate. If you've got a fairly mixed habitat quality, then the two species tend to occur at sort of more or less equal numbers, and then when you get down into the more urbanized environment, then the ricale tends to dominate because it's got much more capacity to take advantage of other food sources and so the food sources. So that's the general picture. If we take the taurans, look, I mean one of the factors that's got to be faced up to is will the presence of a strong ricali population make it difficult for platypus to get established? And that is one of the key issues because, look, the two species, there's not a lot of aggression between them, but ricali will definitely, you know, defend their resources, perhaps more effectively than the platypus will.
Geoff Williams:Ricali are armed with fairly big teeth, whereas the platypus isn't, and therefore it's believed in most encounters, the ricali will, you know, chase the platypus out of its territory. When we're doing platypus surveys, where the two species occur together, for example when we examine the tail of the platypus, you'll often find lots of little nicks out of the back of the tail, and we interpret this as, basically what's happening is the ricalia is giving them little bites. It's biting their tail, saying get out, get out, we don't like you because you're eating our food, go away. And so they put this constant pressure on them to move on. So we think this is what happens. Interestingly though, the platypus can stand up for itself In the only very well-documented instance of violence between the two species.
Geoff Williams:What happened was a fight took place over eight minutes and, to cut a very long story short, at the end of eight minutes it was the platypus that swam off with a dead ricale in its back feet. Basically, what had happened is the platypus had grabbed the water rat by its back feet, held it underwater for long enough to drown it, and so the platypus is not quite as defenceless as we would think. But having said all that, look, I think you can't get around the fact that when you've got a very high density of ricali population in the urban areas, it may be very difficult for platypus to insert themselves naturally in that. In the reintroductions that have been done to date, that hasn't really been an issue. In the bigger reintroduction project we did in Cardinia Creek near Melbourne, ricali were not a big issue there at all and so it didn't arise, but the taurons will be a much, much different story.
Melissa Martin:And I guess, just to finish off, the last question and it is maybe building on what you've already said is because platypus eat. We know they eat 50% of their body weight daily in water bugs and the ricali and the platypus would be, I guess, not fighting but trying to get enough food for each other, and we kind of talked about how they had their own strengths if they were to fight each other. They had their own strengths to protect their resources and protect their population. And what do you think would be the key tactics from your experience to manage that? I guess introduction of platypus to an already existing rickily populated area.
Geoff Williams:Well, look, I think what we know, I mean two things are going to be important. I mean we need, in addition to doing more sort of study of the habitat quality of the torrents, there is, I think, going to have to be more work put into the actual distribution of the recaling population. Now, I mean, what we know about recaling population is what I said earlier they tend to be higher in numbers in disturbed habitats and somewhat lesser in good quality habitats. So we would predict for the torrents that the upper catchment is where there will be less recaling and the upper catchment also tends to be where the best quality is anyway. So I think the pattern of the reintroduction, based upon what we've done with other platypus reintroductions, is that you would start in the upper catchment and try to build up the platypus numbers there and then allow natural dispersal to take place. In other words, once there are enough juveniles being produced by the platypus in the upper catchment, the juveniles will naturally have to disperse into the lower catchment and at that point in time it will be an issue of can they, you know, cope with going down into an area where they may be hassled a bit by the ricale?
Geoff Williams:And that is something which I guess is just one of the hard facts of life. I mean, you know that occurs in a lot of places now and you know either the platypus are going to make it there or they're not. And if they don't make it there, one would have to hope that there is enough good quality habitat in the upper torrens for the population to be supported. So I think, you know, at the risk of sounding a bit sort of negative, I think the reintroduction of platypus to the Torrens has got a lot of good prospects. I don't know you will ever get to the point where you'll be able to walk from the, you know, the festival hall, festival centre or whatever it's called, in the middle of Adelaide and go and see a platypus there.
Melissa Martin:Yeah.
Geoff Williams:There is always going to be just the same as there is in Melbourne. You know there are plenty of platypus in the upper catchment, but you won't necessarily see them at Fling District Station. You'll have to put up with seeing Rakaile instead, which is not a bad alternative.
Melissa Martin:Just to finish off, I'm wondering if you have any from your career in the environment sector around Australia. What are your clear takeaways that you would give people up and coming their career into the sector?
Geoff Williams:Look, never knock back any opportunity to get experience in any aspect of environmental management.
Geoff Williams:You know, I mean a lot of universities these days don't necessarily provide enough hands-on experience of handling animals, so I would strongly suggest to people that they try to find opportunities to volunteer with wildlife in its widest range of things, because I think the ability to you know, work with animals in the wild is perhaps being lost and I still think in the long run, that is something which we've got to encourage people still to do.
Geoff Williams:So get out there and try and find where researchers are working in your area and see what you can do to join them in volunteer things in your area and see what you can do to join them in volunteer things.
Geoff Williams:The second thing is don't lose sight of the fact that getting involved with community groups is also really important, because definitely the trend for the future will be that more and more environmental work will be done more and more by citizen science and by environmental community groups, and therefore I think there is a bit of a tendency for these to be filled by older members of the population, and there's nothing wrong with that, but I think more young people should be getting involved if they are looking for a career in the environment. They need to get involved, firstly because it's good hands-on experience, but it's also good experience of how to work with community groups, which will be a key aspect of any work you do in the environment these days. So I think the key message is I would say to people, is don't be put off by joining groups that might be, you know, outside your normal age group, even if it's old buggers like me.
Melissa Martin:Cool, great. That brings us to an end. Thank you so much, jeff, for your time today I feel like I've learned a lot about platypus, and I hope our listeners have too. Thanks for your time.
Geoff Williams:Pleasure and we look forward to seeing how the Torrance Project progresses, and we certainly hope there'll be a day when we'll have platypus in South Australia in good numbers again.
Melissa Martin:And that brings us to an end of this episode of the Green Adelaide Podcast. This pod was recorded on Kaurna land and I acknowledge and pay my respects to the Kaurna people as the traditional custodians of the land. The Green Adelaide Podcast is your insider scoop on all things cool, green and wild in metropolitan South Australia. I am your host, melissa Martin, and we'll be back next month with an all new episode, not a rerun, a new episode. So please subscribe to our podcast for new episode alerts. Bye-bye.