Natural World (1983) s28e13 Episode Script

Cassowaries

The tropical rainforests of the northeastern coast of Australia are one of the oldest forests on Earth.
They're so extraordinary, they've been declared a World Heritage area.
And in these forests, there still roams an ancient and mysterious creature.
A giant flightless bird.
The cassowary is as tall as a man, and has dagger-like claws and a lethal kick.
But as few as 1,500 of them now remain in these forests.
Charismatic and bizarre, the cassowary has a remarkable appetite for large fruit.
Youngsters still play in the paperbark swamps, but urgent intervention is needed to secure their future.
Cyclones, a regular occurrence in this tropical climate, are now becoming increasingly severe.
And pressures from the human population are increasing, too.
Australia's southern cassowary is in trouble.
Cassowaries are related to those other giant flightless birds that include the ostrich and the emu.
But unlike its relatives which live in open country, the cassowary prefers the dense vegetation of the rainforest.
It's the beginning of breeding season.
A female is looking for a mate.
Her deep, low frequency calls travel far through the forest.
A male approaches very warily.
She is bigger than he is.
And stronger.
The size of the helmet-like casque on her head indicates her age and dominance.
The brilliant colour of her neck and her dangling wattles probably act as a beacon in the forest gloom.
The submissive male follows her majesty several paces behind.
She will take as many as three different mates in a season.
He displays in front of her.
She seems impressed and leads him deeper into the forest.
The pair will spend at least a month courting and mating.
But as soon as the eggs are laid, the female will leave the area.
The rest of the work is left to him.
Some of the chicks developing inside these eggs may not be his, but even so, he will incubate them all and rear all the chicks.
He'll sit here for fifty days and fifty nights.
He feeds only very occasionally.
As a result, he will lose up to a third of his body weight before incubation is finished.
But so long as he stays here, the eggs are safe.
This is the way cassowaries have always lived.
Secure in the depths of the forest.
But the coastal towns of Queensland are expanding and this one, Mission Beach, now extends right to the very edge of a tract of World Heritage rainforest.
And courting cassowaries sometimes wander into town.
Local residents are delighted.
I love the cassowaries.
They're just wonderful, wonderful creatures.
We've got a very small pond out the back and they come to drink at that which is why we see so many.
But in the summer time, he would always just go and stand in it and look like, "this is so nice," you know? We don't know this one.
And I think it is a female.
We know this bloke? No.
We don't have pets.
We don't need pets.
We have cassowaries.
But danger threatens.
A cyclone is building out in the Coral Sea.
Birds and people could be in for a rough time.
Cyclones are common here, but on 20th March 2006 Cyclone Larry speeds towards the coast with unprecedented fury.
BROADCASTER: 'This morning, 'a giant weather system is bearing down 'on the far North Queensland coast.
'Winds of 190 kilometres '.
.
it is expected to cross the coast of far north Queensland 'within two hours.
' Mission Beach and the cassowaries' precious rainforest are directly in the path of a fast moving cyclone.
BROADCASTER: 'Winds of up to 290 kilometres lashed 'the north Queensland coast this morning 'as the category five cyclone hit.
'Authorities in Queensland still can't estimate the full extent 'of the damage from one of the worst cyclones ever to hit the state.
' A great swathe, 100 kilometres wide, is cut through the forest.
The damage is so great that it will be years before the vegetation recovers enough to support the birds.
In the immediate aftermath, however, there is a glut of fruit, blown down by the wind.
But cassowaries need up to five kilograms of fruit a day and soon the windfall is gone.
The birds leave the devastated forest in search of more.
A banana plantation might provide it.
But cassowaries are territorial, they don't share and there's another bird already here.
The bigger one fiercely defends its claim.
And the smaller one, almost inevitably, loses.
HORN BEEPS In the three weeks after the cyclone, four birds are killed on the roads.
But the town is a source of food and the starving birds have become beggars.
Following the cyclone, there were cassowaries everywhere.
They were quite displaced.
They were looking for food.
The forest was in a very bad state and we had them coming up to the house nearly every day.
My eldest son was quite distressed.
Initially, we thought it was his experience of the cyclone, but after after talking to him about it more, we realised that it was fear of the cassowaries, and he didn't want to play outside.
If one saw a cassowary, they would call "Cassowary alert! Cassowary alert!" and everyone would run and hide in the cubby or on the stairs until the cassowary had passed and things were safe.
More and more cassowaries start to wander through the town, and that causes problems for both the people and the birds.
Something needs to be done.
Scott Sullivan leads a Queensland Parks and Wildlife team and he is called in to deal with the problem.
I'm the man with the food, rooster.
This cassowary's really skinny.
You can see its backbone, the ridge along its back, and there's no food here for it.
The vet will tranquillise it and the team will relocate it to some undamaged forest.
Ssh.
.
Everyone quiet.
He's ready to rock and roll.
Got him? That was brains over the buzzard.
It takes a while for the sedative to work.
I might even circle around the top end and get around him, then I can stand up the front end and he might walk back this way a bit.
Can you keep a visual on him? He's remarkably upright.
Get me the net, quick.
They'll need some body armour too, before they can handle the bird.
Bring it in.
Bring it in.
Don't push him.
Don't push him.
Where's your vests? You'll have to jump this one.
Let him come, let him come.
Let him come.
Get on, get on.
Time for snappy decisions.
Well done.
I could kiss you.
HE LAUGHS See the claw? Take notice of the size of that claw.
That's the primary weapon of defence.
You're gonna start pushing as far as you can and when you're ready for the final push and let go, we'll drop the door.
My biggest fear was when it got to the end of here, we've got an open backyard that leads out on to the main road.
And if you've got a bird that's slightly dazed by drugs, the last thing we want it doing is walking out in amongst the traffic.
For the next four months, Scott and the cassowary response team are kept busy relocating birds.
HE WHISTLES Come on, little birdie.
Can you guys hang back a bit, just so we can get out to that fenceline? You're on, boys? Yep.
The birds are taken as far as 80 kilometres away to forest beyond the cyclone-affected area.
This is good cassowary habitat and many of the birds can be released straight back into the wild.
Some, however, are injured or malnourished, or too young to fend for themselves and these are brought into the Cassowary Rehabilitation Centre at Mission Beach.
But their future must lie back in the forest.
We're going up to get an overview of the cassowary habitat around Mission Beach and to see what areas that the cassowaries might be using.
You can really see how the rainforest is broken up into pockets by roads and by development.
It's understandable that the cassowaries had such a tough time after the cyclone.
The cassowaries literally had nowhere to go.
Three months later, and Scott can see that the forest around Mission Beach is still far from recovering.
But beyond the cyclone-damaged area there is still healthy rainforest, where life for the cassowaries is continuing as normal.
Incubation has come to an end and the patient male has four tiny chicks to look after.
The chicks stick close to dad.
They're just two weeks old.
This is the most vulnerable time of their lives and they must quickly learn all they can.
Essentially, those chicks just model themselves off dad.
So dad mooches around and does cassowary business and then the babies will start to emulate that.
It's amusing to watch a cassowary when he's teaching his chicks, because he might be pecking fungus off a tree or he might be picking up a particular seed in the forest and all the chicks will gather around him and they'll mimic those same behaviours.
In doing so, they're getting fed but they're also learning.
The chicks will be looked after by the male until they are at least nine months old and ready to fend for themselves.
It's the dry season and dad must keep them moving through his territory in search of food and water.
Cassowaries need to drink frequently throughout the day and will do so, even if the waterholes are as muddy as this one.
The chicks drink enthusiastically.
Dad, with his thick black cloak of feathers, is obviously feeling the heat.
The chicks seem to be rather unsure about the water, but with their lighter coats, they are not over-heating.
For dad, the water may also soothe the itch from parasites.
The chicks' colours camouflage them very well against the leaf litter and helps to protect them from predators.
The family would normally have this range to themselves.
But dad becomes aware of the presence of another bird and he calls the chicks to him.
This older trespasser with the large head casque is not just a casual visitor.
This is a giant female and she is not to be messed with.
She's come for the food.
CASSOWARY CALLS The smaller male tries to avoid trouble by making little submissive calls.
The female might well be the mother of the chicks, but even so, she would have had nothing to do with them since she laid them as eggs.
To her, the family are just competitors and she wants to scare them off.
CASSOWARY CALLS The male retreats and the chicks follow as quickly as they can.
When they are all a safe distance away, Dad fluffs up his feathers to provide the youngsters with a refuge.
CHICK CALLS But in the hurry to escape, one has been left behind.
CALLING CONTINUES For a little lost chick, the forest is full of dangers.
And night is coming on.
A large monitor lizard is looking for a meal.
By itself, the chick has no chance.
Two months later, and the three remaining chicks are striding out after dad.
They're growing in confidence as well as size.
Their legs are now longer, but it will be some time before they begin to look like an adult cassowary.
One of them even plucks up the courage to take a bath with dad.
Dad clacks his beak to get their attention.
"This is how you find insects.
" Not so long ago, they just followed behind.
But now they can travel further afield and they are becoming more inquisitive.
Dad introduces them to the delights of fungus.
This is an important food source for them at times when there is not much fruit.
Back at Mission Beach, a wounded chick has been brought in to the vet after being attacked by dogs.
Let's have a look at him.
All right? Yeah.
The wound was sort of pretty bad when he first came in.
How does it look? It looks pretty good now.
There's just the tiniest little scar remaining.
He'll be fine in a few days' time.
He's in pretty good nick, condition-wise.
He's quite fat, quite solid and quite a bright and active little guy.
Yeah, orphan chicks, it's probably not the most uncommon reason for receiving them.
The dogs attack the adults, then the chicks have got no-one to look after them.
What do you reckon? Give him a run in the day yard? We can let him out into this pen here.
We're just going to have to lock him into that big cage at night just so that no scrub pythons or anything can get him.
Yeah, let's let him go.
Let him go.
He'll be fine.
He'll be fine out here.
Fantastic.
For the next year, the rehab team will try to give him the skills he'll need when he's released back into the wild.
But not all the birds are so lucky.
Apparently this cassowary was attacked by two dogs yesterday evening and had numerous lacerations and puncture wounds.
When dogs are in a pack, they have a pack mentality and they just try to kill the animal.
Since the cyclone, three birds have been killed by dogs and another twelve hit by cars.
For Julia Conole, the autopsy result is not surprising.
We've got a five centimetre tear on the medial aspect of the left hind into the muscle to the bone.
Right hind in a similar place, massive bruising.
This is one of the worst birds I've ever seen attacked by dogs.
There wasn't a spare centimetre of flesh that hadn't been damaged.
And there's no way anything could have survived those injuries.
The dogs should be put down, because this is what It just shits me.
People think their dogs can just do what they want.
Because the dogs won't be hungry.
They'll just be doing it for fun.
But as Scott knows, it's not just the cassowaries that are at risk in this shared habitat.
It's also the people.
Do you mind if I walk along the back and have a look at it from We don't mind but I don't think the neighbours will like it much.
I'll poke my head over the fence, if she feeds There's no fence.
Yeah.
The locals have known Reggie for years.
She is a big female who lives in the forest next door.
But she's hungry and she's becoming aggressive.
There's cases that we've heard from this bird where it's chased people.
It chased a woman that had a baby in a pram.
If it managed to jump up and rake down with its feet, those inner claws could literally unzip a person.
If a crocodile was dangerous, we'd remove it, we have to do the same thing with a cassowary as well.
Oh, it's just the way I want you.
Just follow her.
The vet actually hit the bird right on the point of the bone which is what bent the needle.
Hardly any of the drug went into the bird.
Got her that time.
Tranquillising wild cassowaries is not an exact science.
And when each bird is so precious, vets prefer to err on the side of caution by using a lower dose of anaesthetic.
The plan now is if she'll let the drug take a little bit of effect and if we can get her to sit down, we'll sneak up there with the net, throw the net over the top of her and she's had the wind knocked out of her enough by that stage that we should be able to do it without any danger to our staff.
She's feeling very woozy.
There we go.
Bring the net.
She's obviously got still a fair bit of spunk left in her and OK, pit tag going in.
Hang on a sec.
Righto.
And while we're relocating her, it's a good opportunity for us to attach a transmitter and then see how the animal behaves post-relocation.
We attach a microchip as well underneath the skin, so we can identify the animal a little bit later on.
But this section where we physically restrain the animal is obviously very dangerous.
We're applying weight to the body of the animal to keep it restrained.
The animal weighs up to 50 kilos and we've got three gentlemen here that are all a good 80 kilos or better holding the animal down, restraining its legs.
These legs are like a set of chainsaws.
So we're holding them firm against the body.
There's that really sharp inside claw.
If we keep that up against the body and away from us, we should do OK.
Have we got both legs in? Yes.
We do now.
Both legs in.
Big push, ready.
Go! Down, down, down, down, down.
That's the hardest capture I've ever done.
How about you, Graham? Yeah.
The drugs laid her down but didn't slow her down, if that makes any sense.
I think we might have underestimated her weight, slightly.
Female cassowaries will go up a good 60 kilo or so.
We dosed her for what, 50 odd? 50, yeah.
But she's not as big as some of the cassowaries we've seen so far.
She put up a fight right to the end, and you've got to ever be aware of those big feet being able to kick back and do some awesome damage to your face, your chest, and any other part of your body.
But it was good work.
Reggie is being taken to a patch of forest behind Mission Beach which the team thinks should be able to support her.
By the time they get there, she'll have recovered from the anaesthetic.
With luck, the traumatic experience of being captured will discourage her from bothering people again.
The radio transmitter she's been fitted with will allow the team to track her over the coming months to find out where she goes.
That's it.
Well, done.
All the relocated birds have been radio-tagged.
Much is still unknown about cassowaries, so every piece of information Scott and his team can obtain about their movements will help in our understanding of the birds' behaviour and of their needs.
BLEEPING Seven months after the cyclone and cassowaries are still wandering into Mission Beach.
It's clear that the damaged forest is not yet able to support them.
And the birds are hanging around longer and longer, staking out their claims in suburbia.
Local people are concerned that the birds are starving and so feed them.
But Parks and Wildlife are worried that the birds might begin to treat the town as their main source of food and so abandon the forest altogether.
So the team have set up 60 feeding stations throughout the cyclone-affected forest to help sustain the birds and draw them back from human habitation.
The feed stations were really set in place just to supplement the diet of the cassowaries.
It was basically to give them a top-up, keep their bellies full and keep them in the forest where they actually belonged, until the forest had time to recover enough that they could forage just from the forest resources alone.
The time for the forest to recover is another one that we couldn't judge that easily.
It's a one-in-how-many-year event that we have a cyclone of the magnitude of Cyclone Larry.
As a result of that, it was really just a 'suck it and see' with this and we put the science in place to monitor the forest and then, as the forest began to recover to an extent that the cassowaries could use it, that's when we started to remove the feed stations.
With help from the community, the rangers are putting out as much as a 1,000 kilos of fruit a week.
Normally, a male wouldn't risk bringing a chick near other large birds but here there's no choice.
It will be many months before the forest canopy begins to recover.
Meanwhile, there is little shade and the birds are suffering under the tropical sun.
The forest pools bring some relief.
Adults are surprisingly good swimmers and will, in fact, readily cross rivers, if necessary.
Beyond the cyclone-affected area, the forest still provides plenty of shade, water and fruit.
Dad and the chicks are doing well.
The youngsters are now eight months old and have lost their stripes.
Even so, it takes practice to get down a whole gardenia fruit in one go.
But one of the chicks is in trouble.
While its siblings fossick for food, it just sits.
Maybe it's just injured.
It certainly can't walk properly.
But the family has to keep moving to find food.
They may well walk up to seven kilometres a day.
The youngster must try to keep up.
Our knowledge of cassowaries in the wild is still limited, but it's estimated that less than half of the cassowary chicks in the coastal rainforest reach maturity.
Next morning and dad has only two chicks still with him.
He's led them out of the rainforest and into the nearby paperbark swamp.
Cassowaries will explore all kinds of forest in their search for food.
And they will eat all kinds of things fruit and fungus, foliage, insects and even small dead mammals.
Dad keeps watch for the missing youngster.
He recognises a high-pitched call.
BIRD CALLS Remarkably, the youngster who fell behind has survived the night.
Physical contact between adult and the chicks seems to be very important.
Surprisingly, Reggie has found her way back to the very Mission Beach garden where she was captured.
But she's lost her transmitter and she is not in good shape.
Do you want full breakfast? I only got continental today.
You didn't you get enough, did you? It's not fair.
Give me a kiss.
Good girl.
Lovely girl, aren't you? You're a lovely girl.
The beauty comes from within.
Hmm.
The residents, worried by Reggie's loss of feathers, have called in Scott and Graham the vet.
Hello, big chook.
I've got a little bit of fruit here, too.
Hello, Ken.
How're you doing? Yeah, good, good.
So any ideas in terms of what you think's causing the feather loss? Um, sure, yeah.
The most likely thing is actually some sort of hormonal deficiency or trauma or over-preening, or these mite parasites that they do get.
But this looks very much to be more a systemic or a metabolic problem rather than something simple.
Right, we're coming, we're coming.
One bit at a time.
Yeah, ready to go.
I probably got a good shot there when you just come back, Scott, actually.
What, over here? Yeah.
Got it all? Yep, got the lot.
You're a champ.
Absolute champ.
We'll give you one more piece for being a good girl.
So she's actually got some feather regrowth.
She's got some feather regrowth, but it's abnormal.
Normally as feathers come through, they come through fully formed, whereas these are coming through in stumps.
We're looking for blood counts, signs of infection.
More importantly in this bird, we want to check hormone levels if we can.
Thus the need for a fair amount of blood, cos there is quite a few tests happening there.
The condition of her skin and feathers is quite remarkable and certainly now she's a bit of a shadow of her former self.
Yeah, a bit further.
Just lift a bit higher.
Don't be shy to lift her up.
Yep, just watch where you are the moment, Ken, because if she kicks, you will absolutely wear it.
It's all right.
I got her.
The strange disease may be contagious, so to protect other birds, they decide to quarantine her and run some more tests.
One week later, and Reggie's results are back.
The tests were a little inconclusive.
The pathologist is suspicious of a virus called circo virus.
Like in parrots? We're not certain at this stage.
We haven't been able to isolate the virus.
The pathology of the skin looks suspicious - as if it is.
But we haven't had that confirmed as yet.
It's not a disease we've seen in cassowaries previously, but the possibility of being immune suppressed following the cyclone, having shortness of food, weakness in the immune system would have contributed to the It's made her a bit susceptible? For sure.
That's why we'd like to certainly keep her in quarantine, because there's the potential that it could be spread to other cassowaries in the area.
Because cassowary numbers are so low, every single bird matters and Reggie will have to undergo more tests.
A year after the cyclone, the forest is at last recovering and cassowaries are playing an important part in its regeneration.
Birds use trees.
But trees also use birds.
And for some trees, only a very large bird is up to the task.
Studying the cassowaries' role is ecologist, Dr David Westcott.
The forest is looking good.
There's lots of recovery now and cassowaries are contributing to that by their passed seed dispersal.
Like most of us, cassowaries are really enthusiastic about eating, and this is the result of all of that eating.
A beautiful pile of bits and pieces, a range of different species.
The thing that cassowaries do that is different to most of the other animals in here is that they can disperse large seeded fruits and they can do that in very large quantities.
The other species can move large seeds, but they usually do it one or two at a time.
Cassowaries can do dozens, hundreds maybe.
Over the coming weeks and months, these seeds will germinate, and what we'll end up with is a little clump of seedlings.
So as the fruit goes through the cassowary, it scrapes off cells from the inside of a cassowary's stomach lining and those cells are passed out in the dung, and what we're trying to do is to use the DNA that those cells contain to be able to genetically fingerprint the individuals.
Then we can actually estimate the number of individuals that there are in a given area and that's one of the key pieces of information that you need to manage an endangered species - an estimate of how many animals are actually there.
The latest calculation suggests that there are only about 1,500 cassowaries remaining in the whole of Australia.
Their survival depends on the existence of healthy and continuous rainforests.
But the birds here must constantly cross roads to get from one fragment of forest to the next.
Much of the coastal rainforest had already been cleared before the World Heritage boundaries were drawn, and unprotected forest is still being felled to make way for human developments.
In Australia, the southern cassowary is only to be found along the northeastern Queensland coast.
But all the surviving forests, protected or unprotected, are now under threat from climate change.
Research is more necessary than ever.
Four giant cranes located in tropical rainforests around the world are enabling ecologists to study the forest from floor to canopy.
By rotating the 50 metre jib through 360 degrees, they can monitor an entire hectare of forest in minute detail.
Other scientists are examining the rich leaf litter on the ground to build up a picture of how the rainforest functions and just how diverse it is.
Changes in the behaviour of leaf-eating insects may give an early warning of how the forest is responding to the stress of climate change.
Climatologists are now predicting longer drier dry seasons and severe cyclones.
Whatever damages the rainforest, will inevitably have an effect on the cassowaries.
If the forest disappears, so will they.
Dad's teenagers are now much more adventurous and leave him for hours at a time, to play what appears to be their version of hide and seek.
But life is not all games.
The youngsters don't know it, but their lives are about to change.
The big female is back.
LOW ROLLING CALL But it's not their food she wants this time.
It's their dad that she's after.
He knows what she wants.
But before she will mate with him, there's something he has to do.
He must get rid of the kids.
It's not easy to persuade them to go.
They have been dependent on him from the time they were hatched.
One way is to chase them off.
Another way is to lead them into the bush and then slip away, hoping that they won't notice.
SCREECHING CALL Now they are on their own.
The Rehabilitation Centre is still busy.
Since Cyclone Larry, 15 birds of all ages have been brought in.
Come on.
Come on.
Orphans spend a few months longer here than they would with a male in the wild.
It takes longer for them to learn from humans.
Come on, come on.
They love the pawpaw.
We've had these young birds in the compound here for about 13 months, and that's round about the time that the parents actually, or the dad, kicks them out, so they have to go and fend for themselves.
And, um, as of this Wednesday, we're releasing three smaller ones.
Yeah, each individual bird's got their own personality.
Um, yeah, I'm certainly going to miss them.
Just stand on the mound, just behind Morris.
The surrogate dads, too, must help the young cassowaries become independent.
No, no, whoo, whoo, whoo.
Everybody stop.
He's coming in behind you guys.
He's done it again.
THEY CHUCKLE Beautiful net.
That's it.
Watch the angle of the bird.
One, two, three.
Well done.
This is what makes all the work of rescue and rehabilitation since the cyclone, worthwhile - putting individual cassowaries back into the wild.
These are the lucky ones.
But will rescuing a few birds at a time be enough? The birds of Mission Beach need more than one-on-one help.
They urgently need their fragmented forests to be connected by wildlife corridors where they can live without human interference.
It's the wet season again.
It will bring life-giving rains or perhaps another cyclone.
The young siblings we have been following are now emerging as individuals.
But they have yet to develop the full adult regalia of casques, wattles and brilliant necks.
It will take another three years for them to reach sexual maturity.
They have spent nearly ten months together as brothers and sisters but that is now coming to an end.
There's time for one last game.
But the playful rivalry now takes on a new edge.
They must separate and find territories of their own.
But how many of them will survive? And will there be enough rainforest to shelter future generations? The remarkable cassowary that has had such a long and ancient past is today walking into an uncertain future.

Previous EpisodeNext Episode