River.Monsters.S01E03.Alligator.Gar

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Transcript

00:00My name is Jeremy Wade.

00:03I'm an explorer, a biologist and a fisherman.

00:07Look at this! There it is!

00:10I've caught many extraordinary fish from rivers all around the world.

00:14Fish that can be described as real monsters.

00:19Normally, I have to travel halfway around the world to find my quarry.

00:23Here we go.

00:24The biggest, some would say baddest, freshwater fish on the planet.

00:30It's not often I hear of a river monster in my own backyard.

00:35But this is exactly what's happened.

00:38A report in a German newspaper says swimmers are being attacked in a lake outside Berlin.

00:44This isn't a far-off exotic place.

00:47A river monster within 10 miles of a 21st century European capital.

00:52Can it really be true?

00:54It's an opportunity not to be missed.

00:58I'm already packing my equipment.

01:00I have my suspicions as to the identity of the culprit.

01:03And if I'm right, it's a fish with a monstrous reputation.

01:07Chronicled since medieval times.

01:10There it is! There it is! There it is!

01:13The Wells is Europe's largest freshwater fish, capable of reaching over 200 pounds.

01:28I've been doing some research into this predatory member of the catfish family.

01:44And I'm finding that ever since records began, Europe seems to have had its very own well-documented freshwater man-eater.

01:53It appears the Wells catfish is actually no stranger to making front page news.

01:58There are stories about this species going back literally for centuries, portraying it as a man-eating monster.

02:07I've been doing a bit of research. Quite frankly, I had no idea it had such a reputation.

02:14Back in the 1500s, a human head and a hand with gold rings found inside the stomach.

02:211630, the corpse of a seven-year-old child. Body of a woman. Two girls devoured.

02:28It just goes on and on. But all this is just so tantalising.

02:33There are no hard facts and figures unless, you know, you count something like that.

02:39If that was the equivalent of your front page story in the 16th century, would you go in the water?

02:49It would be too easy to dismiss these tales as the work of superstitious, unscientific medieval minds.

02:56Attacks and human body parts turning up in Wells' stomachs have been reported across Eastern Europe from Russia to Poland through the ages right up to the present day.

03:09I recently came across this report in a German newspaper of swimmers in a lake being attacked by what is thought to be a large Wells catfish.

03:24I'm on my way to Germany to investigate these attacks and maybe solve the mystery of a serial killer with its roots in Europe's medieval past.

03:40Germany is at the forefront of urban expansion.

03:43Although steeped in history, it is now coated in glass and steel.

03:47Hardly the place for a man-eating monster.

03:52Schlachtensee is a lake just ten minutes from Berlin's city centre.

03:56And it's just become Germany's very own Loch Ness.

04:00This is where the attacks are happening.

04:03Over a mile long and up to 700 feet across, the lake was formed in the last ice age.

04:09These cool waters have always been a refuge for Wells catfish.

04:13And falling to over 25 feet in places, it's plenty deep enough to hide an absolute monster.

04:22The attacks were localised, concentrated in two small areas.

04:28Strangely, areas according to local fishermen, not traditionally the places to hunt for Wells.

04:33So just what happened, I'm going to ask one of the victims, Jonas Feig.

04:43What exactly did you do when you came down that day?

04:45Maybe two or three months ago.

04:48I was swimming 10 or 20 seconds out of the lake.

04:53Suddenly, something big bit me.

04:56I don't know what it was, but it was a very big shock for me.

05:01Pain and shock. It hurts very much, of course.

05:04Almost exactly here?

05:06Yes, right here.

05:08In a freshwater lake so far from the sea, the last thing you would expect is to get attacked by a fish.

05:15It's just not supposed to happen.

05:18Being bitten by a Wells is to experience the power of two hard plates, packed with hundreds of needle-sharp teeth.

05:24Huge jaw muscles create a crushing force. A bite is like being grabbed by a vice, covered in coarse sandpaper.

05:36Before this happened, you used to quite enjoy coming here?

05:39Of course. Every day I was swimming here.

05:42But after that, yeah, I don't swim again.

05:46Normally I wait 100 or 200 people are swimming here.

05:49So definitely people have been put off, you think?

05:51Yes, yes, of course.

05:54But Jonas wasn't the only victim.

05:57In almost the identical place, Katharina and her friend Clara had an encounter that has spooked them out of the water for good.

06:04Just on a normal summer day and we wanted to swim a little bit and meet friends, so we went to the lake.

06:12We were swimming in the water, just treading water and talking to each other.

06:23There was something swimming around our legs, but we couldn't really define it.

06:28It was like a snake in the water.

06:31Then suddenly there was something on my leg.

06:35Then there was a wound on my leg, there was blood.

06:46There were two parts, that part here and the other one on the other side.

06:51I went to hospital with my mother.

06:54They reacted really shocked, the doctors, because they've never seen anything like that before.

07:01And there were other attacks, the same pattern each time.

07:05Swimmers bitten on their legs, sent terrified out of the water, bleeding.

07:10Will these 21st century attacks prove that this European river monster is no medieval myth?

07:20What I want to find out is what provoked these attacks.

07:23And are whales catfish really capable of what they stand accused of?

07:31To find out what's going on below, I'm working with my cameraman Simon and a mini submarine.

07:38We have also enlisted the help of Dr. Christian Wolter from the Berlin Fisheries to give me an expert opinion.

07:45We're here to examine the scene of the crime and see whether knowledge of the biology of the wells could explain what exactly happened to trigger such aggression.

07:56That's about ten metres out, isn't it?

07:58That is about where the boy said he was attacked.

08:01What we could do is take it down there.

08:03So just over a metre.

08:05It's only about, yeah, you're straight in weed at a metre depth.

08:08Yeah, that's okay.

08:09I'd have thought you'd be out of your depth there.

08:11You could stand up in that water, couldn't you, almost?

08:12Yeah.

08:14So it's weedy and shallow.

08:16But for Dr. Wolter, this is just the information he needs to understand what is going on.

08:22The wells were just doing what every parent does, protecting their offspring.

08:28The swimmers had trespassed into their nursery.

08:31So is there anything special or unusual about where they took place, do you think?

08:35These are common spawning places and so on.

08:39That's why it might be the reason why it occurred so close to the bank.

08:44The place that we've heard about the attacks happening, that would be a potential spawning place.

08:49Catfish is a plant spawner.

08:50They build nests and plants where they lay their egg and then they guard the net.

08:56Then it's the only explanation that it was during the breeding time that they had the nest there.

09:02We are guarding the nest and attacked something which comes too close.

09:07For this particular catfish, it was a huge stress to guard the nest and have almost swimmers around.

09:16So it was actually a provoked attack. It was protecting the nest.

09:23Freshwater crayfish and other fish will eat eggs from an unguarded nest.

09:27To prevent this, the male catfish sits over its 300,000 yellow eggs, protecting them from all comers, large or small.

09:43There are two essential qualities that make a man-eater.

09:46Wales catfish certainly have the attitude, but do they have the capacity?

09:51Do they literally have the stomach for the job?

09:53As a younger angler, I caught smaller Wales.

09:59But how big do they need to get to pose a serious threat to a human?

10:04There's no point fishing over the attack sites. Breeding is over.

10:09I've hooked up with local fisherman, Horst Statterjee.

10:13He knows where the Wales are likely to be now.

10:16I'll take a stick and do it with a stick.

10:18Through the mouth.

10:21Me too.

10:22But first, we've got to get over the language barrier.

10:25And we can't do a photo.

10:27Yeah.

10:29Oh, hang on, right.

10:31Oh, I understand.

10:33He's a butcher.

10:34Okay, so now just fishing?

10:36Fishing?

10:40Right.

10:42Always with two.

10:43One glove, no good, not enough. Always with two. One glove, the fish can twist and twist you around. So we have two gloves.

10:53Finally, with the best spots pinpointed, we want to start fishing at dusk.

10:58So this is the place to fish?

11:03Wales are night stalkers. Their bodies are bulging with sensory receptors.

11:11The lateral line that all fish have allows them to sense water vibrations.

11:16But catfish also have extra receptors in their skin.

11:19Those tentacles are more than just feelers. They can taste the water for slight chemical changes.

11:24Any clue that leads them to a meal, which can be anything from fish to crustaceans, even water birds.

11:43When you're up against these super senses, fishing gear for Wales needs to be tough, but you also need a bit of delicacy.

11:49I've got very strong, like 80 kilo breaking strain braided line there, so you can literally just hang on.

11:57You don't have to let them take any line at all. You just hang on and try and stop them getting anywhere near that wood.

12:03Float that slides, but only up as far as the knot. Going down to a fairly big single hook.

12:14And something on that hook that smells tasty, so a dead fish as bait should hopefully draw a large catfish in.

12:21The Schlachtensee catfish prove elusive. But my trip has not been wasted.

12:36I have confirmed that these fish have an aggressive attitude.

12:52It seems that these attacks in Berlin weren't predatory in their intent, but defensive, territorial behaviour at breeding time.

13:02But that's actually academic as far as the victims were concerned.

13:05They came away with bleeding wounds on their legs, which underlines the chilling truth.

13:11A large Welsh catfish has both the size and the fearlessness to be a potential man-eater.

13:18If there's one place where I'm going to find out just how big the Welsh catfish grows and how potentially dangerous it is,

13:26it's here, the Rio Ebro in northern Spain.

13:29The fish is introduced. It's been here a little more than 30 years.

13:34But in that time, you know, they're catching fish bigger than I am.

13:38I mean, they're growing massive.

13:39So, although part of me is a little bit dubious about coming here because it is an artificial situation,

13:45I'm also quite excited because I think that's a very good chance that in the next few days

13:50I'm going to see a seriously big fish on the end of my line.

13:56Northern Spain, the River Ebro.

14:01In 1974, a German scientist came here and released some Welsh into this river.

14:08Ever since, not only have they grown in numbers, but also in size.

14:14The Welsh has become Spain's very own Frankenstein monster.

14:19There are three reasons why the Welsh catfish are growing so big in this river.

14:23It's a mixture of man-made and natural.

14:25For a start, you've got three of these huge dams and it just means there's so much more water,

14:29more space for the fish to live in.

14:31On top of that, this water is hot.

14:33The fish, being a cold-blooded animal, can just feed and grow for more months of the year

14:38than they do in Eastern Europe and in Berlin.

14:40This place was stuffed with fish anyway, particularly carp.

14:43The anglers are coming in, they're throwing in huge amounts of bait

14:46and descending the whole system into hyperdrive.

14:57This river has a policy of catch and release.

15:00So every year, the biggest fish are even bigger than the year before.

15:04Monsters of over 200 pounds already prowl these waters.

15:09Wales can live to 80 years.

15:13Such fish are a massive lure to fishermen from all over the world.

15:24To test just how voracious these catfish are, I head into one of the Ebro's swollen tributaries.

15:29My guide tells me the fish are lurking right in at the margins.

15:33They are waiting to ambush fish in the current and also to grab anything that drops in from the banks.

15:38Very energetic, active fishing.

15:41That's quite precise as well.

15:43On the move, not sitting around waiting.

15:47And it's the kind of fishing where you're left in no doubt if you've got a bite.

15:50You're going to see it, feel it, hear it as something just launches itself at this

15:54and sort of wrenches on the rod.

16:00Ah, yes, yes, yes, yes, yes!

16:02Good!

16:08Whee! Going downstream, watch the oar.

16:10Watch the oar.

16:11Right.

16:17Ah!

16:18Gone, gone, gone, gone, gone.

16:21Hey!

16:22I'm not doing very well.

16:24Everything's happening too quickly.

16:26This is the last place I'd expect to find a fat, wallowing catfish.

16:30But it shows how you can misjudge these guys.

16:33I'm learning that there's more to Wales' behaviour than I thought.

16:43Ah, yes, yes, yes, yes, yes!

16:45Third one!

16:48Open the wheel!

16:49Open the wheel!

16:50Open the wheel!

16:51Open the...

16:52Off, off, off, off, off!

16:53It's off again.

16:56It's off!

16:57Literally took within about a second of the lure hitting the water.

17:01About six inches from the bank.

17:03This water is cracking along at such a rate.

17:05Yeah.

17:06This is like a fast running pace.

17:08That's the place to let it sink a little bit and then twitch a little bit.

17:13That's what I'm doing.

17:14And you'll see the attacks coming direct.

17:15The fish is in the water and let it sink.

17:16Yeah.

17:17Oh!

17:18Absolutely.

17:19Two strikes, no fish.

17:20Damn!

17:22The whales have made themselves totally at home here.

17:24Not just in the main channels, but throughout the whole river system.

17:29As apex predators, they have a confidence that I'm about to witness firsthand.

17:35These fish are scared of nothing.

17:38Look at this.

17:44That's a big fish.

17:47I could almost reach down and grab his mouth.

17:52Do you have a calamari?

17:55That's a catfish here.

17:57It's big.

17:58It's 140 pounds plus.

17:59It is two feet beneath me.

18:01The bank goes down here.

18:03I am looking into its mouth.

18:05I could almost reach down and touch it.

18:08Oh, the fish has backed off.

18:09I think he could see me.

18:10I'm going to throw this really hard.

18:18No reaction.

18:19No reaction.

18:20The fish is just melting away backwards.

18:30This is a really rare sight.

18:33That fish is seven foot long.

18:34It's about 140 pounds at least.

18:37And it was in the margins.

18:38And I could see the whole fish.

18:40There it is.

18:45That's a sight.

18:46That is a rare sight.

18:48That is a big fish.

18:49If I got down on my knees then, I could have patted him on the head.

18:52Mouth like that, right underneath me.

18:54And looking down on its back, this wonderful light camo pattern.

18:58This disruptive sort of black and white.

19:01Through a stone.

19:03To see if that would be a reaction.

19:05No.

19:06He just reversed back.

19:07And then under the boat and away.

19:10I really like seeing fish like that.

19:11It's fantastic.

19:12Really good.

19:15Any other fish would have been spooked off by that stone.

19:18It would have disappeared in a flash.

19:20And that guy is not even a really big one.

19:26I'm on the banks of the river Ebro in Spain.

19:29Hunting down giant whales catfish.

19:33They're estimated to put on up to 10 pounds a year.

19:37If that's true, it won't be long before an Ebro Wells reaches the man-eating proportions of medieval folklore.

19:44If I'm after a man-eater, I need to catch, at the very least, a man-sized fish.

19:50One that falls on the fat side of 150 pounds.

19:55It's time to rig up.

20:00Rather than casting, we drop our baits over 100 yards out.

20:04Just short of the sunken trees along the flooded river channel.

20:07Take up the slide.

20:08Then, with the high-tech alarms set, I can enjoy the Spanish sun.

20:21And now we wait.

20:23This is not my preferred fishing technique.

20:25I like to feel the line, be in contact with the bait.

20:28But wells are not delicate feeders.

20:31And besides, it's hot here.

20:35Yes, here, here.

20:36And it's about to get hotter.

20:42That's taking line, that's taking line.

20:44That's taking line.

20:46This is my first supersized Spanish wells.

20:49And immediately, it feels seriously big.

20:52Just physical, physical stuff.

20:54Whoa.

21:08A serious burst from that fish when it first took.

21:11It's actually taking line when I struck.

21:13Let's do that.

21:17My forearm is almost cramping up.

21:21It's a good sign.

21:23It's a good sign.

21:27We've got the fish, and that is a big fish.

21:30If I can lean in back.

21:32Yeah.

21:34These Spanish wells are hunting in broad daylight.

21:37They really are breaking their programming.

21:39And these fish even seem used to being handled.

21:42My first fish is 140 pounds, and measures 6 foot 9 inches.

21:46If these fish are putting on 10 pounds a year, then in 20 years, this already massive creature could weigh as much as 340 pounds.

21:57More than double its present size.

21:59And if they do live until 80 years, I'll let you do the maths.

22:03The only thing that will restrict them is food.

22:06But there is one food supply here that is in huge quantities.

22:09Other catfish.

22:11The wells is not just a man-eater.

22:14It's a cannibal.

22:16Just get a sort of a cool, scientific look at this animal.

22:18I mean, the first thing, I mean, it's obviously the thing to do, start at the business end, the head.

22:22You've got, I mean, the main thing is just this very, very wide mouth, about 10 inches across on this animal.

22:28And you've got needle-like teeth.

22:31They are sharp as well.

22:32You know, you put your hand in there and they'll draw blood.

22:34But in terms of getting a grip, just perfect.

22:37You know, if they clamp down tight with those sort of jaw muscles, you're not going to get out of that.

22:41They're just purpose-built for lurking on the bottom and grabbing stuff that comes above them.

22:45And they're going to know that stuff is there, the prey, because their eyes are on top of the head.

22:48But more to the point, they've got these.

22:51And these are just, you know, this is like sort of exosensory perception.

22:55You know, you can tell what's going on in the water.

22:58These will pick up vibrations and also chemicals in, you know, in very sort of, you know, very, very sensitive, very small quantities in both cases.

23:05And the side you've got, very pronounced on this animal, you've got the lateral line.

23:09And this is their super organ, the super touch organ.

23:13It just picks up vibrations in the water, you know, often again at a very low level.

23:16And also you can see here these sort of marks on the skin.

23:21Now, I think these are probably wounds from another fish.

23:25Possibly when this fish was spawning and, you know, they got a little bit too rough and a little bit sort of over-enthusiastic.

23:32Stomach here, that's the vent there.

23:34So actually if it swallows something, they can.

23:37This fish could potentially swallow something that long.

23:40It goes to the back of the throat, which is here.

23:42It opens up this sort of sphincter muscle there.

23:44And it could swallow something about two foot long.

23:48So no problem accommodating those medieval accounts of babies and small children in the belly of the beast.

23:56It looks like whales catfish can swallow prey roughly a third of their own body length.

24:01So if these fish in the ebro keep on growing, it's possible that they could reach a size where they will have man-eating potential.

24:09Fact is following close on the heels of what was once thought to be fiction.

24:14Looking at this fish, it is the perfect predator.

24:17I mean, they do eat anything, literally anything, but they are perfectly equipped to predate and also to come from underneath.

24:25You know, that is just a mouth on the end of a solid, sinuous piece of muscle.

24:33Anyway, I can't hold it much longer.

24:34Wells, like all catfish, can live quite a long time out of water if kept cool and wet.

24:44This guy seems quite reluctant to leave.

24:47Should I leave him there or just walking?

24:50In a split second, the fish turns. I'm just quick enough to escape.

24:59That was the first catfish attack on a human on camera.

25:02I was just wondering, is he going to move?

25:04And he did sort of double round.

25:06And I heard stories of them actually having a bite of somebody who's caught them.

25:09So I thought, that's not going to happen to me.

25:11There's no mark there, there's no mark there, but it has happened.

25:20I fish on into darkness.

25:30And I get another surprise.

25:33That just pulled me on my arse.

25:41Ah, fish on.

25:44Me, pull towards the water.

25:46I thought it was going to go in there.

25:50There's nothing right there.

25:58That's a sizeable fish, sizeable fish.

26:01With so many fishermen around, the only inconvenience these fish suffer for their midnight feasts is a little bit of manhandling.

26:08Imagine being in a river at night with one of these things swimming around your legs.

26:14I don't know, I don't know how big it is yet.

26:16I can see it's big.

26:17You all right?

26:18Yep, yep, yep.

26:24One four eight, I think.

26:25One four seven.

26:26One four seven.

26:27One four seven.

26:34Oh, wide.

26:35It's about nine inches, isn't it?

26:39This fish is almost as heavy as I am.

26:41I mean, it is, this is quite a monstrous beast.

26:45And the power as well.

26:46I felt the power.

26:47The thing nearly pulled me in the river.

26:48So, you know, definitely a fierce predatory animal.

26:51And some of these stories about them may be attacking swimmers.

26:54I don't know.

26:55I couldn't believe them now, having actually seen a sizeable one of these things actually up close.

27:00I'm still short of my target 150 pound beast.

27:09These creatures really are ugly out of the water.

27:12I want to see them in their natural element.

27:15But that means getting into the water.

27:20Cameraman Simon and I are going to try an experiment.

27:23I want to see and film a whales catfish underwater.

27:28I want to see exactly how Europe's biggest freshwater predator operates in its element.

27:34What I really want to see is the moment when the whales gets to strike its prey.

27:40It isn't going to be easy.

27:41This is something that very, very few people get to see.

27:43But I do have a few ideas about what I can use to tempt the fish in.

27:52This is the camera.

27:53And this is what's going to be behind the boat.

27:55And about three feet behind this is going to be the lure.

27:59So it's going to be looking back.

28:01The thing is, this is actually quite a lump of a camera, even though it's a small camera.

28:04So I think, here we go.

28:07Si's got, here we go.

28:08Flotation.

28:09Two if we need.

28:10Two tanks.

28:11And to stop it wibble wobbling around a little bit, because we're angling.

28:14There we go, one of those.

28:15And that will just keep it flying straight and level.

28:18And we'll lob that off the back of the boat.

28:20And we'll see the lure and hopefully we'll see something come up and grab the bait.

28:26I'll need to hang on otherwise, you know,

28:28if something big takes this, the whole monitor could go overboard.

28:33This is actually working really well.

28:35I've got the lure in picture.

28:36It's bang in the middle of the screen.

28:40I'm actually watching.

28:41You know, normally it's just there and you've no idea what's happening.

28:45I can actually see my lure out behind the boat.

28:51A fish, I think it was a carp.

28:53Yeah.

28:54Oh.

28:55We're bumping over the bottom.

28:56Oh dear.

28:57What's going on there?

28:58Right, me too.

28:59In a bit, in a bit, in a bit.

29:00No, it's bumping, it's bumping.

29:02I've lost the lure, haven't I?

29:03I've lost the lure.

29:06I think the camera might have been bashed around a bit though.

29:09Not robust enough, unfortunately, to withstand being bashed along the bottom.

29:17But other than that, actually doing very well.

29:21Before that, there was this grey shadow that appeared from nowhere,

29:24which sort of came and went and it could have been a catfish investigating it

29:28and shying off at the last minute or it could have just been a rock going past,

29:31I don't know.

29:32What I'm about to see is another unexpected aspect of these fish's behaviour.

29:41What we're doing is we're doing something called clunking and it's making a,

29:46sending a sound wave down into the water and we can see on the sonar.

29:51Oh, yes, yes, yes.

29:52Yeah, yeah, yeah.

29:53Oh, there it is, there it is.

29:54I've got it.

29:55There's a catfish, there's a catfish, there's a catfish.

29:56Yeah, it's right under the lure.

29:57Fantastic.

29:58Yeah, yeah.

29:59There he is, there he is, tentacles.

30:00Yeah, yeah, yeah, yeah.

30:01Right, what's happened now?

30:02And it's coming up now, right in the middle of the screen.

30:03Fantastic.

30:04Look at that.

30:05He's attacking the camera.

30:06What this has just demonstrated is that when you've got splashing, when you've got commotion

30:21on the surface, the catfish, which they live on the bottom, they will come up to investigate.

30:23Ah, yes, yes, yes, yes, yes, yes.

30:25Bottom of the screen.

30:26There it is.

30:27There it is.

30:28There it is.

30:29There it is.

30:30There it is.

30:31There it is.

30:32There it is.

30:33There it is.

30:34There it is.

30:35There it is.

30:36There it is! Look at that! There it is!

30:47Oh, he's come off.

30:49Come off.

30:53This is amazing, getting a fish on camera taking a bait,

30:57attracted in by sound and vibration.

31:00Like sharks to a plane crash, these fish fear nothing.

31:04It even attacks the camera.

31:07It's been really good, though, just to actually see what I've seen on the screen.

31:10Very, very rare to see this fish behaviour.

31:13So I feel quite privileged to have seen that.

31:21Although we didn't get a fish into the boat,

31:24I actually feel it was a successful day

31:26because I feel that I've actually learnt a lot about the behaviour,

31:29particularly how they react to vibration,

31:32to commotion on the surface.

31:34Here's this fish that lives on the bottom,

31:36but if it hears something, it comes up and the tentacles are waving

31:39and it investigates.

31:40Without the camera under the water,

31:42you just assume that nothing is happening.

31:44As soon as you put the camera there, dangling under the boat,

31:47you're making the noise with the clonk.

31:49They're coming up into the middle of the water

31:51and they want to know what's going on.

31:53Everything I've seen so far, the reaction of the whales catfish to a bait in the water,

31:59confirms its aggression as a top predator and also its fearlessness.

32:03Combine that with supersizing and you've got a creature

32:07that you really wouldn't want to get too close to in the water.

32:10What I want to know now is just how big a whales would need to be to tackle me in the water.

32:18I've said they look like giant slugs, but in their element they're like supersensitive sharks.

32:24Time for another experiment.

32:29Like most people, if I jump in the water, I don't sink, I float, even after a heavy lunch.

32:34And it's not too difficult, I'm flapping my arms a little bit and my legs,

32:38but the question is, how big would a fish need to be to pull me under?

32:48Right, I've got one dive weight on at the moment, four and a half pounds,

32:52and I can support it actually.

32:56That's harder, it's harder, nine pounds now, doubling the rate of paddling.

33:01But I can still just about keep myself on the surface.

33:06Right, I can support nine pounds with a bit of flapping and flailing of my legs.

33:13We've just weighed this rock, this is going to make it up to 20 pounds.

33:17I'll just see how I do against that combined weight in the water.

33:31That was actually very interesting.

33:3520 pounds of weight attached to me.

33:38I could just about keep my head above water, it was a struggle.

33:42I reckon another five pounds and I'd have just gone, no matter how much my arms and legs would have been flailing around.

33:48And that's interesting because if you ask most people how big a fish would have to be to pull a body under water,

33:54they'd say probably, you know, something about the same size as that person.

33:58Now, I weigh about 175 pounds and on land I can take care of myself.

34:03But in the water, you know, a fish would just have to exert a pull of 25 pounds, about a seventh of my body weight,

34:11and, you know, I wouldn't stand a chance, I'd just be gone.

34:15And if I took a lungful of water underneath there, then nobody would ever see me again.

34:24OK, that just goes to show that it doesn't need to be a huge fish to pull me under.

34:30Let's have a closer look at pulling power.

34:34That 147 pounder pulled me off my feet and almost into the water.

34:38How much force can I generate?

34:42I couldn't even pull in our director and she's half my weight.

34:46She's a match for me, even one handed.

34:52So I could be pulled under the water by a fish just half my size, 75 to 100 pounds.

34:58And the thing about the Ebro is that the river is just full of fish that size and much bigger.

35:04Which possibly explains why you don't see very many people swimming.

35:11With only a few days left in northern Spain, I'm trying to break the 150 pound marker that I have set myself.

35:17My respect for these fish over the past few days has really grown.

35:23oh, oh, oh, oh, oh, oh, oh.

35:26Oh, oh, oh, oh, oh, oh, oh, oh, oh, oh!

35:44Ah!

35:47Ah!

35:49Ha, ha, ha!

35:51If this one pulls me over, I'm in real trouble.

35:54I was nearly tipping forward over that edge,

35:56so I'm just going a little bit.

36:02My groin is starting to ache.

36:05This is strong.

36:07The rod's jammed in.

36:10Such physical stuff.

36:12Physical work.

36:15It's coming up.

36:18Strong fish.

36:19But I think it's, yeah, it's tiring.

36:21Tiring, tiring.

36:24There it is.

36:27There's the fish.

36:31Good grief.

36:32My crutch is killing me.

36:37And there it is.

36:40But does it weigh more than 150 pounds?

36:43For the measure of the beast, that is seven foot one, two, three, four.

36:50Seven foot four inches.

36:52And then we open the mouth.

36:56You can actually hear the echo coming out of the mouth there.

36:58Hello, hello.

36:59And I can see its gullet opening and closing.

37:02If I was so inclined, I could put my fist down there quite easily.

37:06That is an eating machine.

37:09The whole thing is nearly eight foot of just solid rippling muscle.

37:13If that grabbed hold of your leg, that's an unpleasant enough thought.

37:16But if that decided not to let go and you were swimming, you'd be history.

37:20I'm about 175 pounds on a good day or a bad day, depending on how you look at it.

37:30This fish could be more than that.

37:3574 kilos.

37:36That's about 163 pounds.

37:39Not quite as big and fat and ugly as I am.

37:50What I find really hard to tread is that I was doing those experiments where I was trying to see how much force I could exert in the water.

37:58And there was somebody on the back with a spring balance, just hooked around their finger, reading off, okay, 30 or 40 pounds.

38:04This thing in the water was almost pulling me off the bank.

38:09I was having to dig in and really act like I was in a type of war.

38:12How something with nothing solid to actually grab hold of can exert that force in the water, you know, I find quite mind boggling.

38:20It is very, very impressive indeed.

38:24And now it's time to let this guy go.

38:29Let's see how he reacts.

38:31The fish has recovered a bit, maybe a bit more than I have.

38:37I'm going to put it back in the water.

38:42If it does have a go at me, I'm going to actually stand my ground and see if it, a bit like an elephant, see if it's a false charge or will it actually go and grab my leg.

38:49This is what I'm trying to remember.

38:53This fish is bigger than I am.

38:55It's got a few inches on me.

38:57I've got a few pounds on this fish, but I'm in the water.

39:00My extra weight actually counts for nothing.

39:03It's the fish's environment sinking down towards my foot.

39:06I think my reflexes overruled what I was wanting to do, which was stand my ground.

39:21But I can visualise it too much, what might be going on down there, what might be going through its mind.

39:27So don't tangle these guys in their environment is the message.

39:32Wales catfish are predators with a lot of attitude.

39:45Two of the fish that I caught turned on me while I was releasing them.

39:50But as far as eating people, a Wales will swallow anything that fits inside its monstrous gut.

40:02Ah, yes, yes, yes.

40:04And if that includes you, well, it's no respecter of species.

40:08It seems that if they ever went away, these medieval monsters are now back, alive and well, and still growing in the river Ebro in northern Spain.

40:20This is quite a monstrous beast.

40:22If I came back here in 20 or 30 years, I think it's possible there could be something in here that is bigger than anything that's ever existed before.