In the Wild (1992) s01e18 Episode Script

The Sanctuary Part 2 Lagoons and Mangroves

Oh! That's good.
Most of us Australians take running water for granted - we turn on a tap in the house or we have rivers running past.
But the big part of Australia is arid, it's desolate, it's desert, there's no water.
And all life depends on water at some stage.
Even those totally desert-adapted things still have to have water.
And for a country that's so arid, Australians seem to be the least water-conscious people in the world.
All water begins as rain but after that it comes in all shapes and sizes.
It can form into big lily lagoons in the upland country.
These are often under enormous threat, especially from man's introduced animals.
When they're not damaged, they're a beautiful sight.
And birds - like this snake bird, or darter - make full use of them.
But the most delightful residents are these lily trotters, or Jesus birds.
They appear to walk on the surface of the water - they're actually on the leaves - and that's where they get that name from.
Of those places in Australia which have ample water, the richest is probably this North Queensland coastal region.
This little bloke wandered into camp last night, just up there.
Like all animals, I need water and I'm camped near the water - good, sweet, fresh water where I can use it for all the purposes of life that I need, like this animal, the birds, everything else.
This is the water rat.
And there are a number of races of the water rat in Australia.
In other words, there's no distinct demarcation between them.
In the south-west corner of Australia, there's a big black fellow.
In the north-west, there's a grey-blue looking one.
This little fellow's got a lovely yellow belly and is much smaller than the others.
But these are races, and the cline moves around Australia, and there's no place where you can say this one stops and that one ends.
This one has this marvellous little face specifically designed for living in the water, tiny ears to keep the water out, little eyes and a magnificent bunch of whiskers and, of course, very good teeth for biting.
He'd love to bite me if he could but I'm holding him in such a way that he can't.
His back feet are webbed for swimming, and you can see the webs between the toes quite clearly, but even so, they're clawed.
When he's in the water, they swim extremely efficiently.
This is one of the animals that invaded Australia somewhere in the first possible land bridge.
He came in from the north, most likely and has adapted to living on water.
Now, it is very likely that this is the first non-marsupial, perhaps apart from bats, to come into Australia.
Because he's adapted to water living, because he's adapted to going into the sea - they do go out to sea, eat crabs on reefs and things like that - it is quite likely that this was the first animal of all to come in.
Where the waters are deeper, the water lilies disappear, except in the shallow banks, and these long chains of open billabongs appear.
The deep water has different animals to the shallow water.
And to find out, you have to net.
So And we have a bag full of goodies.
Get rid of the weed.
Ah, there's something flapping in there.
It's not possible always to carry an aquarium in the field but it is possible to carry a plastic bag.
All you need to do is run your goodies in there and you can have a good look at whatever it is that you've got in the bag.
That's an apogonid.
What little kids call gobbleguts.
There's a story that they've got a mouth so big that they can open it and turn themselves inside out trying to eat a kingfish bait.
But it's not true, of course.
They are a mouth-breeder.
That big mouth is for catching food.
Great big gills.
They open their mouth and (SLURPS) suck in very quickly and suck in small food.
But its other use is to keep eggs and young.
The eggs are laid by the female, the male scoops them up in his mouth and they carry their eggs and their young in their mouth.
So they don't eat while they're breeding.
There's all sorts of other goodies in here too.
Let's see Hold it.
(LAUGHS) Greed'll get you nowhere.
(LAUGHS) Now, there, of course, is the perfect water animal.
A bit of stir-up of mud brings out shrimps and things, and this fellow's come up from the deeper water under the lilies and logs to see what he can find.
He's a boofhead tortoise or turtle.
He's totally adapted to this area - a good, strong solid shell, webbed feet with claws.
The short tail tells me it's a female.
Male tortoises have very long tails.
And this head, very strong biting jaws.
Very strong biting jaws for catching and eating things like shrimp and fish, all those sort of things.
The strong plate means he's armoured against anything except a really big crocodile who can swallow him whole, then digest him.
Very efficient animals.
They swim beautifully.
These blokes are very active on land, and during the wet season they come up, lay eggs.
They also hunt at night.
I'll show you how active he is on land.
Gonna sulk now, are ya? Having a look around to see what it's all about first.
"Ah, there's a nice bit of shade.
Think I'll head for that.
" Having a quiet amble down.
Getting fast as he gets closer to the water.
Falls in a few tracks and pads.
Very active and agile, though for an animal as clumsy as that.
Now he'll go back to what he got interfered with in the first place - looking for something to eat.
Tortoises aren't the only hunters in these open waters.
Birds, like these kingfishers, are very obvious with their beautiful colours.
Others are underwater birds, like cormorants.
On the edge of this big billabong we have reed beds and swamps.
And in this, other life is found.
The secret of survival is awareness.
Here's someone watching now.
A beautiful green tree snake.
Lovely yellow throat.
Quite harmless.
Scared stiff, hoping I won't eat him.
Just pretending to be one of the creepers or vines in the area.
And he'll just slip off quietly into another tree when I leave.
Yeah, there you are.
(LAUGHS) Oh, come on, it's all bluff.
(HISSES) Oh, dear me, look at that mouth.
All bluff.
A beautifully harmless snake (HISSES) called a black-headed python.
But look at this great bluff act he's putting on - he's gonna tear me apart, because that's his primary defence.
That black head from the little scales on the head Whoo, I'm winded.
Long way chasing him.
makes him look very much like a poisonous snake.
And that's how he protects himself, by pretending to be a poisonous snake.
Now, he's having a bite.
He's decided he doesn't like himself so he's giving it away again.
They can bite.
All snakes can bite.
But because he's a python he has no poisonous fangs.
See the grip he's got on me? Really curling around.
Put him around a bit more.
Come on, bring your head around so you can show yourself off.
He's just another one of the animals that lives here in the river and uses the river, or the water - he goes right down as far as the mangroves.
But this same species can move right up into the rocky hilltops.
It's liable to be found anywhere across the northern part of Australia.
This one's about to shed his skin.
You can see that sort of an opaque film over his eye, and that film shows It's the scale over his eye which is shed at the same time as the rest of his skin.
Well, let's show the people how well you can swim.
Come on, un wind! It's alright when they're this size.
When they get a big bigger, they're apt to be a little strong.
Because of the water and the dampness around these lagoons, they're usually surrounded by a specific environment - a paperbark swamp.
Paperbarks are specially adapted to growing in wet conditions.
And they've got a whole host of strange life forms associated with them.
(CHUCKLES) Just not enough.
It's a weird-Iooking beast, isn't it? It's actually a plant, very prickly which I particularly want because it's most uncomfortable up here.
As soon as I touch it, I'm immediately covered with little biting, stinging ants because this is the fabulous ant plant.
It's a symbiosis - that is, a relationship of two different things which live together for a particular purpose.
This is an epiphyte - a thing that grows on a tree.
I'll just put it down for a moment.
Ooh, yee! Nasty.
Strong ant smell and very nasty, nippy little bite.
This symbiosis is a plant that grows up on a tree - a paperbark in this case - and a colony of ants that live in its base.
Now, the exact relationship isn't really known.
Obviously, there's a defensive thing - if anything touches this plant, the ants swarm all over it, so that's the ants' role, to a degree.
The plant obviously offers a home to the ants.
Ooh.
You can see them all over me too.
Obviously, one of the functions is protective defence.
The ants protect the plant and because they make their home in it, the plant protects the ants.
All of these sort of plants make their homes on the bark of the paperbarks.
During the wet season, they soak up moisture with big, fleshy, bulbous bottoms, and then in the dry season, it's enough to support them.
Well, the ant plant had better go back with me.
I've got a bag here somewhere.
There it is.
Tie it up tightly so the ants can't get at me while I'm carrying it.
Take it back to the lab and have a good look at it because I want to form my own ideas as to why and how these two quite dissimilar things live together.
(STARTS ENGINE) Rivers eventually flow to the sea.
Now, where they join the sea occurs a very specialised habitat - mangroves.
Mangroves are plants that have evolved over the years to meet the impact of alternate salt and fresh water, of massive washes of mud and of extremes of climate.
Entering a mangrove swamp is something of an experience in itself.
It's an eerie, strange world, all on its own.
The animals and plants that make their homes in this area are somewhat strange and different, so I set some traps here yesterday and I'm just coming back to check them out.
You move with caution here.
It's dangerously muddy and slippery.
Aha.
It's one of the tree rats commonly known as bush rats.
And the big problem with rats is that they all look alike.
They're either big, medium or small rats, and that's about all you can say about them.
I'll have a close look at this fella but very carefully because they do bite.
There he goes.
He's got the choice of mud or trees.
This time he chose the mud.
And that's interesting because it's broad daylight - well, it is now - and he should have headed for cover.
But I guess he doesn't really live up in this tree.
His real home is probably up in another hollow tree, and since he's in his own territory, he's headed off to the place he knows is the safest in the daytime.
Daytime's a bad time for rats because that's when all the things that eat rats are around.
This landscape is like something out of 'The Enchanted Forest'.
You sit here long enough and this muted hush, this tangible atmosphere comes to you.
(INSECTS CHIRP) All of these little shapes are like little sculptures.
They're vaguely humanoid, like striving people reaching or wrestling or coming up out of the mud.
Then the trees themselves are twisted and warped like the fairytales from England and the Continent, our ancestral stories of the hobgoblins.
All sorts of animals make their home in this particular half-world.
It's a mixture of land animals and sea animals, both fighting for the same food.
This little sea snail, for example.
He's one of the periwinkles.
He's got a sharp, hard doorway.
He pulls it in behind him and nothing can eat him except the giant rays that come cruising up here when the tide's in and all of this is covered with mud.
Then the rays come nosing in through these roots, find this fellow, and their great, flat, bony jaws just go crunch.
And that's the end of him.
He gets crushed up and they spit out the shell.
So the survivors have now learned to move up the trees.
And you find them up in trees, not down in the mud.
They just graze on the mud.
Every tree trunk is covered with mosses and lichens.
And being tropical, of course, everywhere through here is jungle conditions - epiphytic orchids, ferns, all of those sort of things.
In essence, this mangrove is a particular sort of closed forest, almost a rainforest, but with the added advantage or disadvantage of a constant flushing of salt water.
The roots trap silts and muds, which are precipitated by the presence of sea salt.
And then the mangrove seeds and suckers take root and grow, and new forms and species of mangrove develop under the cover of the others.
This is the sort of thing I mean.
Tide's coming in, the river mouth coming out here, and there's a sandbank built across, and these mangroves are taking advantage of it.
Where the tide sweeps through around there, you can see the water is scouring the bank out, cutting it away and the roots are collapsing in.
But just around the corner here the roots are holding it and the mud is building up and banking out.
And these pioneer.
These are the real controllers.
They send down these big, clutching hands - zonk.
They reach out, and the moment they touch here, they grip.
And then any debris - leaves and branches and logs that are floating down - are caught there, build up, and you get the mud bank building up behind.
And already, you can see in there where they've established it, and you can see the young plants.
And away it goes.
A beautifully logical sequence.
But I've gotta get out before the tide catches me.
Cruising down these tidal river areas is a very exciting and enjoyable time for a naturalist.
There's always waterbirds.
On the move.
Hunting or sunning.
They always have to be cautious.
While they're looking for food, they in turn could be food for something else.
The open space allows you to see your enemies coming, but it also provides room for attack by predators.
Like this red-backed sea eagle.
Perhaps the best way of seeing things in the mangrove is to drift in a boat at night.
Using a spotlight, no motor, just very quietly.
All sorts of things appear.
The day animals are sleeping.
There's a little pied cormorant, a little restless in the light.
There's a sacred kingfisher.
He's also disturbed.
He knows it's not morning and yet the light is there.
The safest place is in the branches over the water.
There's something.
Gently now.
(CHUCKLES) You beauty.
That's the sort of thing I'm talking about, with evolution taking place.
This is the rufous shrike-thrush.
On the western side of the continent there's an identical bird except the one on the western side has got a black bill - this fellow's got a very pale bill.
Sometime in the past, when the sea came down through the central part of Australia, the race of shrike-thrushes was cut off.
And the ones up here in Queensland developed this race with the pale bill, and the ones on the western side are the dark-bill ones.
And there is a recently discovered hybrid race in between.
Superb singers.
Hear them in the mangroves every day.
Get up in the forest country surrounding the mangrove too.
Very curious little bird.
And as soon as you sit down, and start (CHIRPS) calling, they come in, have a look and see what's happening.
He knows it's night-time but he just doesn't quite know what it's all about.
Eyes closed, and he should be asleep.
Well, I think we'd better find him a spot to put him back to sleep.
Perhaps in the morning I'll let you go.
That'd be a good idea.
Then nothing will get you.
If I let him go now, he'll blunder off into the mangroves and something will catch him either tonight or first thing in the morning.
Just another one of these specialised little animals that's adapted to this mangrove situation.
Beautiful thing.
And there are so many of these beautiful things because the mangrove has probably got the richest assemblage of different life forms you can find anywhere in Australia.
But because it's not pretty, because it's full of mud and sandflies and smells and crocodiles, nobody goes there and nobody cares.
If we really want to save our Australian heritage, we must preserve more mangroves.

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