28 Red-tailed Black-cockatoos
About this episode
The call of a Red-tailed Black-cockatoo can carry a whole conservation story. Scientist Richard Hill shares the community work helping protect the endangered south-eastern Red-tailed Black-Cockatoo.
Episode illustration: Red-tailed Black-cockatoo
Richard Hill is a conservation biologist who works on threatened birds and mammals. He shifted to Casterton with his family to study the region's endangered Red-tailed Black Cockatoo, and he's never looked back. Richard’s work involves understanding and mitigating key threats to the south-eastern Red-tailed Black-Cockatoo and Brolga, as well as working on a number of threatened small and medium-sized mammals.
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Kirsty: The guest in this episode of Weekend Birder lives and works on the country of the Jardwadjali people. I would like to pay my respects to elders past and present. The Jardwadjali peoples connections to the land, animals, seas, waterways and sky continues to be part of the very fibres of their being. I would like to thank them for their significant contributions to community, to science, and to the health of country.
Kirsty: Welcome to Weekend Birder. I'm your host, Kirsty Costa, and I am thrilled to introduce you to Richard Hill. Richard is a conservation biologist and he is here to tell us all about the Red-tailed Black-cockatoo. Firstly, let's find out how Richard grew his interest in birds.
Richard: My dad had birds in averies when I was young. He had budgerigars and quail, I was particularly struck by the quail for some reason, but probably more so through my grandfather who was a farmer in western Victoria and he had interest in birds. And I remember one year we gave grandfather and grandma a copy of the Reader's Digest Book of Australian Bird Illustrations, something like that. One of the first full colour big coffee table books. So all Australian birds. And somehow that really grabbed me. And that plus Pa had a farmer's interest, or more than just a latent interest, in birds. And he taught me the local names of common birds around the Grey-shrike Thrush, the tomtit, the Yellow-rumped Thornbill common in parts of western Victoria and grasslands and stuff. So through that, the terror of having the magpies attack me as I'd ride down the laneway to pick up the mail, all those things meant birds really grabbed me. I grew up in Melbourne and one stage spent a few years, almost three years, on Christmas Island doing my Masters and was eventually summoned back to Melbourne to finish writing it up, which didn't seem like a great idea to me. But anyway, we ended back in Melbourne with my girlfriend (and then soon to be wife) and in Melbourne in writing up the Masters. I was working for BirdLife and knew there was a job on Red-tailed Black-cockatoos that was coming up and I was lucky enough to get it. And we then decided to move to western Victoria to work on this what was then a three year full time project. Yes, that's how we came to Casterton. I had this wonderful job which was to look at and try and understand how this rare black cockatoo was going. Trying to understand the key threats which were keeping it so, so rare and how we might try and understand and better manage it to help help it recover.
Kirsty: Cockatoos are a family of large, long lived and very noisy parrots with movable crests on their heads. Australia is home to 14 of the 21 global species of cockatoo, with others also found in Papua New Guinea, Indonesia, the Solomon Islands and the Philippines. Galahs are the most widespread cockatoo and you can find them throughout Australia. You might have also seen members of the cockatoo family like corellas, Gang Gang cockatoos, cockatiels and Sulphur-crested Cockatoos.
Richard: Parrots and cockatoos is such a big part of our landscape. And the noises they make. I mean, they're something like the Sulphur-crested Cockatoo, the big white cockatoo with a lovely lemon crest. When you look for it and see it, that lovely lemon wash on the underside of the wings of a of a Sulphur-crested Cockatoo, just a gorgeous bird. And then it opens its mouth and you say, "Holy moly, that's such an awful sound!". And, you know, so the sounds are a big part of our landscape as well. And they don't they often don't sort of really match, do they? But the Red-tailed Black-cockatoo is it's a widespread species. The subspecies, you know, a variety, if you like, in Queensland, another one in Northern Territory and the Kimberleys, there's one in far southwest western Australia, and then there's a desert one. That's four so far. And then there's one in south west Victoria straddling the border with South Australia. Those other subspecies for the most part are reasonably widespread and common. The Little Forest one in south-west WA is a bit like ours. It's smaller and a very real forest specialist. It's still a lot more common, even though it's listed as threatened. It's much more common than our bird over here, which is the smallest of the Red-tailed Blacks and has a short wings and short tail and occurs just in this small area and is really quite rare. There's only about 1000 to 1500 of them. A beautiful little thing is called "graptogyne", which means brightly coloured female. The female is the most brightly coloured of the different Red-tailed Black-cockatoos, really striking spots and bars on the breast and those beautiful tail feathers. I've got one here. Obviously listeners can't see, but it's this black with these panels of yellow and a sort of fire orangey red and just the most beautiful tail feathers and do have real cultural significance to traditional owners of this part of the world as well. The male is really the black cockatoo. It's black or he opens his tail. Do you see the lovely orangey red panels of throughout the tail? But that's concealed when the when the tail is closed. So he's basically black and the female is really more a dark charcoal grey, but she's got lots and lots of very pale lemony cream coloured bars and spots on her breast and on over her head and on her shoulders. And her tail feather is the one that I just described previously with the lovely panels of of yellow and black and orange fire. Sometimes people mistake them. So I saw a flock and there was all these Red-taileds, but there was a whole lot of yellow tails in there as well. And the yellow tails are like females in those flocks. And in fact, the young ones as well, the all the young birds up until age three, including age three, all have that female plumage and that beautiful tail feather, I think. Fire-tailed Black-cockatoo would be a better name.
Kirsty: As Richard mentioned, the cockatoo that he is researching is the South-eastern Red-tailed Black-cockatoo, which is only found in south east South Australia and south west Victoria. You might know the yellow tailed black cockatoo with its yellow cheek patch and yellow panels on the tail. The Red-tailed Black-cockatoo is different for the reasons that Richard just explained. The South-eastern Red-tailed Black-cockatoo only eats the seeds of two types of stringybark tree. The Brown Stringybark is a gum tree that has thick fibrous bark and can grow up to 40metres in height. Cockatoos will pretty much spend all of their time feeding on the seeds and nuts of this tree.
Richard: And they spend many, many hours a day just sitting in the branches, quietly opening the capsules and taking the seeds out of those nuts. And there's another one called the Buloke, which is a type of casuarina or sheoak. They use that summer and autumn just for a short period when those seeds are actually on the tree. The gum tree is the stringybarks. The seeds stay on the tree, the nuts down the tree for a couple of years. And so there's a continual food source throughout the year and the stringybark in the casuarina is just a month or two, a couple of months, a year.
Kirsty: Spring and early summer is the Red-tailed Black-cockatoos breeding season and they are generally seen alone or in family groups of 2 to 3 birds in autumn and winter flocks of 100 to 250 cockatoos can be seen in areas with a good food supply. Trees also play an important role for the nesting of cockatoos.
Richard: Parrots and cockatoos in Australia basically nest in in tree hollows which develop in gum trees when branches fall off and they rot out and a combination of termites and fungus and things rot out and create these hollows. The size of the hollow you need depends on the size of your body. The Black-cockatoos are big cockatoos. They need big hollows, and that big means 60cm or 60 or 80cm deep, internal diameter of 30cm or so. There's quite big hollows. Those big hollows only develop in big gum trees. So that's what they need. Those big countries are unfortunately much rarer than they used to be because a lot of them occur on good ground that's been converted to farmland. They've been cleared or fallen over. So that's one of the things that these birds seem to be short of now is just those big gum trees in which to nest will be hollows in which to nest.
Kirsty: There are about 1500 South-eastern Red-tailed Black-cockatoos living in the wild, which means that they are endangered and considered a threatened species. So it's important that Richard and his team evaluate how its nesting and breeding is going to do this. Dozens and dozens of nests need to be included in their research so that they can get an estimate of the average nesting success.
Richard: The nests are hard to find. They don't nest in the same place every year. They change nest every year pretty much. Another problem with is the nests tend to be really high and they're really dangerous to get up to or difficult or you need a cherry picker. All these things mean that normal methods that we used to don't really work. And so what we've come up with is a way of using the calls that they make around the nest site, which are quite distinctive. You know, birds are really vocal and like I said, they make a whole range of sounds. Luckily, Red-tailed calls aren't as bad as they're really lovely. Sounds not as awful as the sulphur crested. They actually have quite lovely calls. Not revealing my bias, of course, and they have particular calls that they only use around the nest. And so what we do is put recorders at the nest, at the trees where we've seen them nesting before, which they tend to come back to every 2 to 3 years. So at the start of the breeding season in September, we put on these recorders, which can record for ten weeks continually or not continually, but without changing the batteries kind of thing. And if the if a cockatoo comes there, they tend to come in the evening, the male and female arrive and they use a sort of behaviour which we know pretty well and they call to each other and then the female which may be on the nest because she spends the first six weeks of the nest just sitting on the nest really on the egg and the single way, just one egg or looking after the little baby. So she will give a call from inside the nest. When he starts, he yells out, "I'm coming and coming". And she goes, "Okay, I can hear you". And she climbs out, up out of the nest and she calls there as well. And then she flies off. You can hear quite well on these little recorders. So even though we can't see what's going on, a few of us know the birds well enough. We can then interpret by listening to it. And it's very cool. So you get masses of data from this. It's huge amounts of data and we send it up to a girl, Dani, who's did a PhD and now works as a researcher at Queensland Uni of Technology. And we send these huge hard drives with masses of data up to and she's developed up these computer algorithms to sort through this masses of data using big computer because it's a lot of computing time and stuff and it spits out the end of it saying, "I think a cockatoo is here. I think it was one here". And we just go through and say, "Oh, that was a cockatoo. That was a cockatoo. That one's definitely nesting. I can hear the call". And through that we just develop a history of each nest and can tell whether it was used or not and whether it was successful or not, which is cool. And for the first time we're able to do that.
Kirsty: To give you a quick idea of what these birds sound like. Here is Eddie Smith's recording of the South-eastern Red-tailed Black-cockatoos in flight in South Australia. <Sound of cockatoos> Richard says that the technique that his team uses for recording sound in the Cockatoo's habitat and then using software to locate the Cockatoos' calls in the sound files is leading to finding nests in surprising places.
Richard: We had a student who's just finished his Masters, and I said to him, "Oh, look, it's pretty hard to find a nest. You just can't go and randomly put your recorders out in a tree and expect a cockatoo to turn up". But he did that anyway. So he ignored me. And and really interesting when he came back, if he had put out 20 recorders, maybe five of them had nests in them or something. We only really just started doing this in the last couple of years. So in the next year or two, we're going to get a much better understanding of breeding success and then start to understand what it is about. Those nests are successful versus ones that are not. Are they closer to the stringybark? Are they closer to the stringybark that have had good seed crop in the last 12 months kind of thing? And that's the way we'll build up a better picture of what they need to nest successfully and hopefully how to find and protect and recreate more areas like that.
Kirsty: The main South-eastern Red-tailed Black-cockatoo nest and population monitoring that Richard and his team do every year is organised by BirdLife Australia. People from the community volunteer their time to visit about 70 sites. Richard says that these sites are really big.
Richard: Each one is about 100km², ten by ten, and within that there will be blocks of stringybark and they drive around in their four wheel drives. So this all happens on a single day in May, the first Saturday in May and across the range, this great huge area, it's almost 20,000km² that the bird occurs within within the stringybark areas and they drive those areas listening for and recording cockatoos. That's a big deal. And it's only made possible because people like doing that and they like helping and just love a nice day out in the bush. When I first arrived here, a guy had only recently retired. His name was Dick Cooper. He got in touch with me and said, "I might be able to show you some some cockatoos". And I said, "Sure". And so we met out in the bush and sure enough, he did. He absolutely knew what a cockatoo was. And so we started talking about cockatoos. He'd only recently retired. Sadly, his wife had died in the last couple of years. And this, for him and for the two of us, became such an important relationship and friendship. So I'm getting a bit emotional describing it because he only died two years ago now, I think. But he was such a great friend and became so important in in helping me understand the cockatoos because he'd spent a lot of time watching them himself already. And together we spent hundreds of hours in the bush really driving around or meeting up out in the bush. And also he knew the names of all the farmers around because our bush out here is patches of Bush which are surrounded by farmland. The nests very often were in farmland on private land, and no one was going to let me on just just by tapping on the door and saying, "Hello, I'm from BirdLife Australia. I'd like to come and look at your cockatoos". A lot of people were going to say, "Well, okay, but go somewhere else". But with Dick, he knew all these people and he said we'd either turn up or he'd give them a call and say, "Look, my mate Richard, he's a good fella. He won't leave any gates open". And it was all I needed. And so between us, it was just absolutely crucial in maybe doing my work and in learning. And if we had dignitaries from time to time, we'd have some VIP know the governor of Victoria was one of them at one stage. And and Dick was the he was out every week and said taking his dog Timmy for a walk. And and Dick saw Sharp's track down the end of the saw some birds there the other day you'll be right you'll find some that kind of thing. And otherwise they're very, very hard to find. So it's not a matter of just driving out in the bush and seeing them birdwatchers know that this cockatoo is hard to find and you can spend days and days and days searching fruitlessly for this Cockatoo. So he was so important in many ways.
Kirsty: Thank you for everything you did for Cockatoos, Dick, and for the help that you gave Richard and his team. This episode of Weekend Birder is in your memory and acknowledges your incredible legacy. This is yet another example of the goodness of people and how communities are working together to love and protect birds. Richard's final piece of birdwatching advice for us is to get a decent pair of binoculars.
Richard: The best thing you can do for yourself is to buy a good pair of binoculars. Really, it's such a difference. You can struggle with a pair of poor quality binoculars and just really not get the pleasure that birdwatching brings, because one of the absolute delights of birdwatching is looking closely and having this beautiful, intimate, close up with these animals. And they and good binoculars are so, so wonderful. The detail you can see with them, it's it's such a lovely thing. The rewards can maybe be a bit thin on the ground, but with a good pair of binoculars, you know, just watching a magpie or any common bird or crimson rosella, these things are just in a good pair of binoculars. They sort of leap out of the binoculars and they're just wonderful. And another thing to do, if you're at all musically inclined minded, is that the calls of birds are such a delight. Not that cockatoo I mentioned before the sulphur crested, but so many of our birds. We've got some of the most beautiful songbirds in terms of their calls that they make in the world. The Pied Butcherbird call is considered to be blows the nightingale out of the water. Really, it's just the most gorgeous, gorgeous call. And lots of our songbirds do have. Beautiful calls. So both of those things, but a good pair of binoculars. It's a fabulous start.
Kirsty: Thank you so much for taking the time out of your busy schedule to chat with us, Richard. I have a new appreciation for Red-tailed Black-cockatoos and now know more about where they live, what they eat, and how scientists are researching their nesting behaviors. You can find out more about Richard's research in the episode notes or by visiting the Weekend Birder website. And many thanks to everyone who have recently sent an email or reached out on social media. It's so great to hear from you and I'm so glad that this podcast is of value to you and the people around you.
