0:00:00 > 0:00:00- 888
0:00:00 > 0:00:02- 888- - 888
0:00:02 > 0:00:02- 888
0:00:07 > 0:00:09- 888
0:00:14 > 0:00:16- 888
0:00:22 > 0:00:26- Despite living on this planet - for 240 million years...
0:00:26 > 0:00:31- ..life for the crocodile - hasn't been easy in recent years.
0:00:31 > 0:00:34- Numbers had fallen dramatically - by the '70s...
0:00:34 > 0:00:37- ..because they were hunted by man.
0:00:37 > 0:00:39- Today, it's a different story.
0:00:39 > 0:00:45- Bags and shoes made out of crocodile - skin was the biggest problem...
0:00:45 > 0:00:49- ..for Australia's - native saltwater crocodiles.
0:00:49 > 0:00:53- There were only 3,000 left - in the Northern Territory...
0:00:53 > 0:00:57- ..when zoologist Grahame Webb - started a campaign to save them.
0:00:58 > 0:01:03- Today, 100,000 survive in the wild. - They are now a protected species.
0:01:03 > 0:01:07- Thousands are bred in captivity - to satisfy demand in the market.
0:01:10 > 0:01:15- Grahame opened this crocodile centre - in 1978 to develop his work further.
0:01:15 > 0:01:20- It also presented an opportunity to - educate the public about crocodiles.
0:01:20 > 0:01:23- One of the main attractions - at the park...
0:01:24 > 0:01:26- ..is feeding the crocodiles.
0:01:26 > 0:01:28- This happens three times a day.
0:01:29 > 0:01:32- What have we got - on the line there, Adam?
0:01:32 > 0:01:35- There are more than - a thousand crocodiles in the park.
0:01:36 > 0:01:40- Some are recently hatched, - whilst others are 16 feet in length.
0:01:41 > 0:01:44- They can weigh half a tonne. - It's chicken on the menu today!
0:01:47 > 0:01:49- In prehistoric times...
0:01:49 > 0:01:52- ..the crocodile's ancestor...
0:01:54 > 0:01:59- ..could eat something - as big as a dinosaur.
0:02:00 > 0:02:03- Crocodiles were a lot bigger - back then.
0:02:03 > 0:02:06- They were 40 feet in length.
0:02:06 > 0:02:09- That's a big crocodile!
0:02:11 > 0:02:15- He's so deceptive. - He seems fast asleep.
0:02:15 > 0:02:17- Whoo!
0:02:20 > 0:02:25- They've been studying the area's - freshwater crocodile population...
0:02:26 > 0:02:27- ..for the last 25 years.
0:02:28 > 0:02:31- While the saltwater crocodile - numbers are increasing...
0:02:32 > 0:02:35- ..there are concerns - about their smaller cousins.
0:02:36 > 0:02:42- The biggest threat to them is posed - by the South American cane toad.
0:02:42 > 0:02:45- Its numbers - have increased dramatically...
0:02:46 > 0:02:50- ..since it was introduced - to the country fifty years ago...
0:02:50 > 0:02:52- ..to eat insects - in agricultural crops.
0:02:55 > 0:02:59- The toad and the eggs it lays...
0:03:00 > 0:03:02- ..are poisonous.
0:03:02 > 0:03:05- They can have an adverse effect - on the wildlife...
0:03:06 > 0:03:09- ..around this wetland area - of Australia.
0:03:24 > 0:03:25- During the wet season...
0:03:25 > 0:03:28- ..the water level reaches - halfway up these trees.
0:03:29 > 0:03:32- Today, the McKinlay River's - waterbed is dry.
0:03:32 > 0:03:37- I'm joining the team who monitor - the freshwater crocodiles...
0:03:37 > 0:03:40- ..which live here - during the dry season.
0:04:02 > 0:04:05- Well, here we are on the banks - of the McKinlay River.
0:04:05 > 0:04:10- During the dry season, the area - has an abundance of billabongs...
0:04:10 > 0:04:12- ..which are pools of water.
0:04:12 > 0:04:15- During the wet season, - the pools fill up...
0:04:15 > 0:04:18- ..join together and create a river.
0:04:18 > 0:04:22- These pools are the perfect place - to see freshwater crocodiles.
0:04:23 > 0:04:25- That's what we're here for today.
0:04:28 > 0:04:32- Adam Britton is responsible - for the research work.
0:04:32 > 0:04:35- He'll spend - most of the next three months...
0:04:36 > 0:04:40- ..leading a team of volunteers - to collect the latest data.
0:04:40 > 0:04:44- He was eager to expand his horizons - as we ventured out onto the water.
0:04:44 > 0:04:46- 'Nol' is easier. 'Nol'.
0:04:46 > 0:04:49- 'Nol'? No problems.
0:04:50 > 0:04:53- 'Nol' is backwards, - and 'Ymlaen' is forwards?
0:04:57 > 0:04:59- What's 'hurry up'?
0:04:59 > 0:05:01- 'Siapa dy stwmps'!
0:05:03 > 0:05:05- Siapa dy stwmps!
0:05:08 > 0:05:11- We need to pull backwards - so we don't hit the net.
0:05:12 > 0:05:16- We've placed a net - across the billabong.
0:05:16 > 0:05:22- After around five minutes, - we think we've trapped a big one.
0:05:24 > 0:05:26- We've got a crocodile here.
0:05:26 > 0:05:28- Let's have a look.
0:05:28 > 0:05:30- Let's have a look.- - There he is. Can you see him?
0:05:30 > 0:05:32- Oh, yeah.
0:05:33 > 0:05:38- Instead of 'siapa dy stwmps', I - had to watch out for my 'stwmps'...
0:05:39 > 0:05:42- ..as I guided the first croc - into the boat.
0:05:42 > 0:05:46- I have to admit, - my heart was racing.
0:05:46 > 0:05:48- Just hold him there.
0:05:48 > 0:05:49- Just hold him there.- - OK.
0:05:52 > 0:05:55- We haven't had a chance yet...
0:05:55 > 0:05:58- ..to tape his mouth up.
0:05:58 > 0:06:01- His mouth is so narrow...
0:06:02 > 0:06:05- ..he's got tangled in the net.
0:06:05 > 0:06:09- His teeth are very sharp.
0:06:11 > 0:06:15- You have to know what - you're doing in this situation.
0:06:15 > 0:06:18- Working as a team is so important...
0:06:18 > 0:06:20- ..and you have to trust each other.
0:06:21 > 0:06:25- Adam's put a lot of faith - in his partner for the day!
0:06:25 > 0:06:30- We've been very lucky. - We've trapped one that's quite big.
0:06:30 > 0:06:37- He'd be longer if he hadn't had - a problem with his tail.
0:06:37 > 0:06:43- I think he's had a fight - at some point.
0:06:43 > 0:06:46- He's not as long as he should be.
0:06:51 > 0:06:55- What I'm going to do is put - the screwdriver through his jaws...
0:06:55 > 0:06:58- Gosh, his neck is swelling loads.
0:06:58 > 0:07:02- Can you see this? - His neck has swollen an awful lot.
0:07:03 > 0:07:07- He's biting down very hard.
0:07:08 > 0:07:11- What I'm trying to do - is open his mouth a bit.
0:07:11 > 0:07:13- Shall I keep a hold of his neck?
0:07:13 > 0:07:14- Shall I keep a hold of his neck?- - Just keep holding him.
0:07:15 > 0:07:17- Can you see his teeth?
0:07:17 > 0:07:20- If he loses one, - another will grow in its place.
0:07:20 > 0:07:23- This happens all the time.
0:07:23 > 0:07:28- In a year, - they can lose up to 66 teeth.
0:07:29 > 0:07:32- But they all grow back, - so it doesn't matter.
0:07:33 > 0:07:35- This man's got a lot of faith.
0:07:35 > 0:07:37- Voila!
0:07:37 > 0:07:39- 'Voila', as they say in Welsh!
0:07:42 > 0:07:44- I can't believe I'm doing this.
0:07:45 > 0:07:47- It's a fantastic feeling.
0:07:52 > 0:07:54- OK.
0:07:59 > 0:08:04- With the crocodile's jaws fastened, - we found another one in the net.
0:08:04 > 0:08:06- This one wasn't as quiet!
0:08:06 > 0:08:08- It's quite a big one.
0:08:09 > 0:08:11- He's really big.
0:08:11 > 0:08:13- Just watch his head.
0:08:13 > 0:08:15- Just watch his head.- - Can you lift his bum up?
0:08:15 > 0:08:17- Oh, he's not happy.
0:08:18 > 0:08:24- As you can see, - this crocodile isn't very happy.
0:08:24 > 0:08:25- I don't blame him.
0:08:26 > 0:08:30- But, um... it makes life - a bit more difficult for us...
0:08:30 > 0:08:34- ..and a bit more frightening.
0:08:35 > 0:08:37- OK, boss.
0:08:37 > 0:08:39- Can you hold on to his head?
0:08:40 > 0:08:44- Freshwater crocodiles are smaller - than saltwater crocodiles.
0:08:44 > 0:08:47- This one is almost fully grown.
0:08:51 > 0:08:52- OK.
0:08:52 > 0:08:55- I'm sitting on a crocodile.
0:08:55 > 0:08:58- I've just been bitten by a fly...
0:08:58 > 0:09:03- ..but, right now, - that's the least of my worries!
0:09:06 > 0:09:10- As you can see, - his teeth are quite small.
0:09:10 > 0:09:14- This means that they're growing back - and that he lost a lot of them.
0:09:14 > 0:09:19- It looks like he's eaten something - he couldn't swallow.
0:09:19 > 0:09:23- He's lost a few teeth - in the process.
0:09:23 > 0:09:26- They've only just started - to grow back.
0:09:28 > 0:09:32- They've caught - this crocodile before.
0:09:32 > 0:09:34- They've already marked him.
0:09:35 > 0:09:38- When they go back - and check their records...
0:09:38 > 0:09:42- ..they can find out - where they caught him last time...
0:09:43 > 0:09:47- ..how much he weighed, - how long he was and what he ate.
0:09:50 > 0:09:52- OK, we're nearly done.
0:10:06 > 0:10:08- Grab him, if you want.
0:10:08 > 0:10:11- I can do it. - I've got him, I've got him.
0:10:11 > 0:10:13- Hey, baby!
0:10:15 > 0:10:17- Look at this one - it's a baby.
0:10:18 > 0:10:20- Very cute!
0:10:24 > 0:10:28- If you see a crocodile in the water, - and you can only see his head...
0:10:28 > 0:10:31- ..you know instantly the length - of the rest of the body.
0:10:32 > 0:10:37- The rest of the body - is six times the size of its head.
0:10:40 > 0:10:43- It's a formula that's always right.
0:10:43 > 0:10:48- In contrast to the other - two crocodiles we caught...
0:10:48 > 0:10:50- ..this one's not nasty.
0:10:52 > 0:10:55- He's quite docile.
0:10:55 > 0:10:57- Its neck isn't swollen either.
0:10:57 > 0:10:59- He's not biting down hard.
0:10:59 > 0:11:03- After an exciting and successful - morning, we returned to land...
0:11:03 > 0:11:07- ..to examine - the crocodile prisoners.
0:11:07 > 0:11:10- They're surprisingly heavy.
0:11:17 > 0:11:20- Crocodiles have been monitored here - for over 25 years.
0:11:20 > 0:11:24- Detailed data is kept - about the crocodile population...
0:11:24 > 0:11:27- ..in the McKinlay River - during this period.
0:11:27 > 0:11:31- This data is very useful - to researchers.
0:11:31 > 0:11:34- It provides all sorts - of information.
0:11:36 > 0:11:39- At the moment, - that data is very useful...
0:11:40 > 0:11:44- ..because the cane toad - has been introduced to the area.
0:11:45 > 0:11:50- It was first introduced - to Australia in 1935.
0:11:50 > 0:11:54- It's only been in this area - for the past year.
0:11:54 > 0:11:56- This toad is very poisonous.
0:11:56 > 0:12:01- They're worried that its presence is - reducing the crocodile population...
0:12:02 > 0:12:04- ..in this area.
0:12:04 > 0:12:08- They will look at the data - they collected last year...
0:12:08 > 0:12:11- ..and compare that - with this year's data...
0:12:11 > 0:12:16- ..to see if there's been - any reduction in the numbers.
0:12:18 > 0:12:23- She's been caught four times before - - in this billabong, every time.
0:12:23 > 0:12:26- She was first caught in 1979.
0:12:26 > 0:12:29- She's probably at least - 50 years old.
0:12:29 > 0:12:32- She's quite an old animal.
0:12:32 > 0:12:37- We think that freshwater crocodiles - can live up to 60-70 years old.
0:12:37 > 0:12:42- But, if there are going to be - cane toads here in the wet season...
0:12:42 > 0:12:47- ..this could be the animal's - last year - which is a bit tragic.
0:12:48 > 0:12:52- Time will tell what will happen - during the wet season.
0:12:52 > 0:12:57- For now, they're free and happy - to reach the billabong again!
0:13:01 > 0:13:05- More details about the crocodiles - can be found on our website.
0:13:05 > 0:13:10- After the break, I'll come face to - face with their larger cousins...
0:13:10 > 0:13:13- ..the saltwater crocodiles - of the Adelaide River.
0:13:18 > 0:13:18- 888
0:13:18 > 0:13:20- 888- - 888
0:13:27 > 0:13:31- This is the highlight for me - - the moment I've been waiting for.
0:13:31 > 0:13:36- We're on the Adelaide River - looking for saltwater crocodiles.
0:13:36 > 0:13:39- Yes, the ones that eat people!
0:13:39 > 0:13:42- This is the best time to catch them.
0:13:42 > 0:13:47- The tide is out and they come out - to feed at this time of day...
0:13:47 > 0:13:49- ..when the sun sets.
0:14:00 > 0:14:04- As the sun's heat disappears, - threatening shapes pass our boat...
0:14:04 > 0:14:07- ..under the water's surface.
0:14:07 > 0:14:11- Adam's seen an opportunity - under the shadow of the trees.
0:14:13 > 0:14:15- We're going to target one of them.
0:14:20 > 0:14:22- It's exciting.
0:14:23 > 0:14:28- At the end of the pole, there's - a hook at the end of a strong line.
0:14:28 > 0:14:30- If the croc comes - towards the water...
0:14:31 > 0:14:34- ..Adam will plunge the harpoon - into its nape.
0:14:34 > 0:14:39- But this is a sly one that scurries - away into the thick undergrowth.
0:14:57 > 0:15:00- Well, we lost that one, - unfortunately.
0:15:00 > 0:15:04- We'll carry on looking. - The night is young.
0:15:13 > 0:15:17- It will be easier to catch them - in the water when it's dark.
0:15:24 > 0:15:28- It got very exciting - when it was dark...
0:15:28 > 0:15:31- ..as we lost sight - of the river's immensity.
0:15:39 > 0:15:45- There were crocodiles all around - and Adam had plenty of choice.
0:15:47 > 0:15:50- Well, we've caught a crocodile.
0:15:50 > 0:15:53- It's a female crocodile.
0:15:55 > 0:15:58- It's quite big - eight feet long.
0:15:58 > 0:16:04- At the moment, she's dived down into - the depths because she's scared.
0:16:04 > 0:16:07- We're giving her enough slack...
0:16:07 > 0:16:11- ..to allow her to swim away, - then pull her in, swim away...
0:16:11 > 0:16:13- ..and then pull her in - until she tires.
0:16:14 > 0:16:18- She'll have to resurface soon - to take a breath of air.
0:16:21 > 0:16:26- There was something incredibly - surreal about the situation.
0:16:26 > 0:16:29- We had a powerful crocodile - at the end of our line...
0:16:29 > 0:16:33- ..and we were about to smack her - with one of the oars...
0:16:33 > 0:16:35- ..to make her open her mouth.
0:16:35 > 0:16:40- I didn't hurt her, but she wasn't - happy about the whole thing.
0:16:40 > 0:16:42- It's no surprise, is it?
0:16:50 > 0:16:52- We're pulling the crocodile in...
0:16:52 > 0:16:54- ..and we'll tie her jaws up now.
0:16:55 > 0:16:57- It's an important thing - to remember...
0:16:58 > 0:17:00- ..don't put your hand - near her mouth.
0:17:00 > 0:17:05- Crocodiles don't have the energy - to open their jaws regularly.
0:17:06 > 0:17:10- But when they close their jaws, - they do so with a force...
0:17:10 > 0:17:13- ..that's corresponds - to two tonnes of weight.
0:17:13 > 0:17:16- It's like a lorry - falling on your head!
0:17:16 > 0:17:18- Just put your finger there.
0:17:18 > 0:17:20- Just put your finger there.- - Are you serious?
0:17:27 > 0:17:30- It's hard to believe - that this flimsy piece of tape...
0:17:31 > 0:17:35- ..will keep the jaws closed - while Adam administers the tests.
0:17:35 > 0:17:39- It will all happen inside - our tiny 15 ft boat.
0:17:43 > 0:17:48- As you can see, we're taping up - the crocodile's mouth.
0:17:48 > 0:17:52- It's a frightening experience, - to say the least.
0:17:57 > 0:17:59- Right. - I am as ready as I'll ever be.
0:18:03 > 0:18:07- The four of us were fully aware - of our responsibilities.
0:18:07 > 0:18:11- Otherwise, we'd have an irate - crocodile back in the water...
0:18:11 > 0:18:14- ..and we'd be keeping her company.
0:18:14 > 0:18:16- Shall I grab a leg?
0:18:16 > 0:18:18- I've got it. Hang on.
0:18:21 > 0:18:23- Come here, you bugger!
0:18:23 > 0:18:25- I've got it.
0:18:25 > 0:18:27- Lift it up.
0:18:27 > 0:18:29- Whoo-hoo!
0:18:30 > 0:18:32- Wow!
0:18:35 > 0:18:41- With the three of us sitting on her, - there was no escape... hopefully!
0:18:42 > 0:18:44- This is the harpoon.
0:18:45 > 0:18:47- It's a small device.
0:18:47 > 0:18:52- This enters the crocodile's skin, - like a hook when you're fishing.
0:18:52 > 0:18:57- It's this size to make sure - it doesn't penetrate the muscles.
0:18:58 > 0:19:01- It doesn't harm the crocodile.
0:19:01 > 0:19:06- It's long enough to snare it - by its skin.
0:19:07 > 0:19:12- The scientists are interested - in its immunity from disease.
0:19:12 > 0:19:15- Adam regularly takes - blood and skin samples...
0:19:15 > 0:19:19- ..and it's hoped that - this revolutionary research...
0:19:19 > 0:19:22- ..will lead - to a better understanding...
0:19:22 > 0:19:25- ..and medical benefits for humans.
0:19:25 > 0:19:27- She's about seven feet long.
0:19:32 > 0:19:34- With the worst over...
0:19:34 > 0:19:38- ..the croc senses that it's time - to return to the water.
0:19:38 > 0:19:45- But, first, we have to clarify - one important fact for the data.
0:19:48 > 0:19:52- Adam has just asked me - to find out...
0:19:52 > 0:19:57- ..if this crocodile - is a male or a female.
0:19:57 > 0:20:03- It appears that I have to insert - my finger into this hole...
0:20:03 > 0:20:05- ..to find out!
0:20:09 > 0:20:12- Adam was fairly sure - that this was a female crocodile...
0:20:13 > 0:20:16- ..but there was only one way - to find out for sure.
0:20:16 > 0:20:18- I had to feel around - for its sexual organs.
0:20:20 > 0:20:22- Well, I can't feel anything.
0:20:23 > 0:20:26- That means it's female.
0:20:29 > 0:20:30- So, a little girl.
0:20:30 > 0:20:32- So, a little girl.- - You've got a little girl here.
0:20:33 > 0:20:34- Well, a big girl!
0:20:38 > 0:20:43- This is the most precious part - of the crocodile - the stomach.
0:20:43 > 0:20:49- This is where the skin is smoothest.
0:20:49 > 0:20:53- From 1945 to 1971...
0:20:54 > 0:20:59- ..crocodiles were killed - to provide this skin to make bags.
0:20:59 > 0:21:04- By 1971, the future of crocodiles - was under threat.
0:21:04 > 0:21:10- That's when they decided - to do something about it.
0:21:14 > 0:21:18- It's time for us to get - this one back into the water.
0:21:18 > 0:21:22- First, we need to calm her down.
0:21:33 > 0:21:37- We're preparing to put - the crocodile back into the water.
0:21:37 > 0:21:41- We have to release her - back into the water...
0:21:41 > 0:21:44- ..without the tape over her eyes...
0:21:44 > 0:21:49- ..and the tape and rope - around her jaws.
0:21:50 > 0:21:52- It's quite a feat.
0:21:52 > 0:21:54- We don't want to get hurt either.
0:21:54 > 0:21:59- I think she'll be a bit annoyed - at having been tied up for so long.
0:22:01 > 0:22:03- OK, we just need to put her on here.
0:22:03 > 0:22:06- Are you ready? One, two, three.
0:22:10 > 0:22:14- What we're going to do - is just undo this.
0:22:14 > 0:22:18- And then John, - if you could just put the tail in.
0:22:19 > 0:22:23- OK, are you ready to go? - Just slide the tail in there.
0:22:23 > 0:22:25- Australian saltwater crocodiles...
0:22:26 > 0:22:30- ..have been a protected species - in the wild for the past 30 years.
0:22:30 > 0:22:36- Control schemes which support the - development of crocodile farms...
0:22:36 > 0:22:40- ..have created a more stable - situation in the Northern Territory.
0:22:41 > 0:22:43- Congratulations.
0:22:43 > 0:22:46- It's hoped that - these crocodiles will survive...
0:22:47 > 0:22:51- ..for at least another 240 million - years in the Adelaide River.
0:22:55 > 0:22:59- Next week, I'll be capturing - some wild animals in Africa.
0:22:59 > 0:23:01- For more information, - visit our website.
0:23:04 > 0:23:06- The animals are in there.
0:23:06 > 0:23:11- The sirens will go off again - and then the curtains will close...
0:23:12 > 0:23:15- ..to make them move closer - to the lorry.
0:23:19 > 0:23:22- S4C subtitles by Rh Sion Morgan