0:00:14 > 0:00:19The giant otter - six feet long, from tip to tail.
0:00:19 > 0:00:22They're known in the Amazon as "wolves of the river".
0:00:24 > 0:00:28For me, they hold a special fascination.
0:00:28 > 0:00:32Loud, boisterous and aggressive. They're also loving,
0:00:32 > 0:00:36affectionate and fiercely protective of their family...
0:00:41 > 0:00:45..even if it means risking their lives.
0:00:51 > 0:00:54I first filmed giant otters when I was just a young cameraman
0:00:54 > 0:01:00and got to know a very small, rather goofy, little cub, called Diablo.
0:01:04 > 0:01:08I watched him grow up for almost a year and got very attached to him.
0:01:16 > 0:01:19I've often wondered what happened to Diablo.
0:01:19 > 0:01:22And now, I'm about to find out.
0:01:37 > 0:01:39I last saw Diablo
0:01:39 > 0:01:4213 years ago, in Manu National Park,
0:01:42 > 0:01:46a remote part of the Peruvian Amazon.
0:01:46 > 0:01:51Manu's incredible. The amount of life here blows my mind -
0:01:51 > 0:01:54half a million species of insect,
0:01:54 > 0:01:5810% of all the bird species in the world.
0:02:03 > 0:02:06Nowhere can touch Manu for diversity.
0:02:10 > 0:02:13It's a long way from home, back in Britain.
0:02:16 > 0:02:21My name's Charlie and I've been completely obsessed with otters
0:02:21 > 0:02:23since I was a kid.
0:02:23 > 0:02:25I've rescued orphaned otters,
0:02:25 > 0:02:28I've spent hours filming and watching otters.
0:02:28 > 0:02:30They've all got their own character...
0:02:34 > 0:02:37..and many have become like old friends.
0:02:38 > 0:02:41In Diablo's case, long-lost friends.
0:02:41 > 0:02:45So I can't wait to try and find him again, after all this time.
0:02:47 > 0:02:51My journey across the Andes and down into the Amazon Basin
0:02:51 > 0:02:52takes me almost a week.
0:02:55 > 0:02:58Ooh, just getting swept down.
0:03:00 > 0:03:02Where I'm going, means journeying by boat,
0:03:02 > 0:03:04far beyond any towns or villages,
0:03:04 > 0:03:07right into the headwaters of the Amazon.
0:03:20 > 0:03:27Manu - 17,000 square kilometres of pristine tropical rainforest.
0:03:27 > 0:03:30I just love this place.
0:03:30 > 0:03:34Right in the middle of it, is a stunning oxbow lake
0:03:34 > 0:03:35called Lake Salvador.
0:03:35 > 0:03:40This is where I last saw Diablo, as a cheeky young cub.
0:03:48 > 0:03:52It's late November now, just coming to the end of the dry season.
0:03:52 > 0:03:54For the next six months,
0:03:54 > 0:03:57me and a small crew of local guides and boatmen
0:03:57 > 0:04:00will be calling this place home.
0:04:06 > 0:04:09It's four in the morning and I'm just so excited
0:04:09 > 0:04:12about finally starting the search for Diablo.
0:04:25 > 0:04:27I love the sound of the forest at dawn.
0:04:27 > 0:04:30It's loud, it's like a busy city,
0:04:30 > 0:04:32but there's one sound that I'm just desperate to hear.
0:04:35 > 0:04:38SQUEAKING AND WHISTLING
0:04:38 > 0:04:41There it is!
0:04:45 > 0:04:49Seeing giant otters again, after all this time...
0:04:49 > 0:04:52Well, it's just magical.
0:05:04 > 0:05:08SNORTING
0:05:11 > 0:05:15Is that not the coolest animal in the world?
0:05:17 > 0:05:22But are any of these otters Diablo?
0:05:28 > 0:05:32Otters have got unique throat markings, a bit like fingerprints.
0:05:32 > 0:05:36If I can get a look at the pattern on each otter's throat,
0:05:36 > 0:05:40I might be able to work out if one of them is Diablo.
0:05:54 > 0:05:58There's one otter, he's just a bit bigger than the others.
0:05:58 > 0:06:01He's the one I want to get a better look at.
0:06:01 > 0:06:08I'm trying really hard to get a shot of this otter's chin and throat.
0:06:10 > 0:06:17It's definitely Diablo. Wow, there's the man.
0:06:25 > 0:06:29That's stunning. I can't believe I'm looking at him.
0:06:32 > 0:06:34Just look at him, though. He's rock solid.
0:06:34 > 0:06:40He looks healthy, he's big. You know, this guy's 13.
0:06:40 > 0:06:44That is as old as giant otters get.
0:06:44 > 0:06:48And he looks to me in really good shape.
0:06:56 > 0:07:02Giant otters live in family groups - mum, dad and the teenage kids.
0:07:02 > 0:07:04I just don't know how big his family is,
0:07:04 > 0:07:08but there's just otters everywhere.
0:07:16 > 0:07:19Diablo's obviously a very special otter,
0:07:19 > 0:07:22to have such a big family like this.
0:07:22 > 0:07:25And now that I've found him after all this time,
0:07:25 > 0:07:31all I want to do is sit and just watch. They're just so beautiful.
0:08:39 > 0:08:44Finally, I get the chance to see Diablo out of the water.
0:08:44 > 0:08:49He's busy working on what's politely known as an otter latrine,
0:08:49 > 0:08:52in front of what must be the family den.
0:08:52 > 0:08:56There's a good reason why Diablo's rubbing his feet around
0:08:56 > 0:08:58in the family toilet like this.
0:08:58 > 0:09:01It makes the most almighty stink,
0:09:01 > 0:09:07which warns other otters that this territory belongs to Diablo.
0:09:07 > 0:09:09And then, I understand, why my old friend
0:09:09 > 0:09:12is being so protective of his den.
0:09:15 > 0:09:18That's a cub. That's a cub.
0:09:20 > 0:09:22Oh, my God.
0:09:22 > 0:09:26If she's got it in her mouth, that's the mum with it in her mouth.
0:09:27 > 0:09:30Wow, look at that. Tiny.
0:09:32 > 0:09:36That is really young. That can't be more than six weeks old.'
0:09:38 > 0:09:41He's got another one.
0:09:43 > 0:09:46There's at least two of them.
0:09:55 > 0:09:58Come on. Yeah, yeah.
0:10:02 > 0:10:06Seeing otter cubs in the wild like this is incredibly rare.
0:10:07 > 0:10:09This is a real surprise.
0:10:11 > 0:10:14That's amazing. That is a big family.
0:10:16 > 0:10:20This seems to be some sort of swimming lesson.
0:10:20 > 0:10:24I know it sounds bizarre, but otter cubs don't actually like water,
0:10:24 > 0:10:28so lessons like this are obviously essential.
0:10:42 > 0:10:45There's one cub in particular who catches my eye,
0:10:45 > 0:10:47not because he's muddier than the others,
0:10:47 > 0:10:51but because he really doesn't like the water.
0:10:56 > 0:10:59And despite his mum's best efforts, all he wants to do
0:10:59 > 0:11:03is get back to the warmth and security of the den.
0:11:19 > 0:11:22The other cubs all seem to be enduring their swimming lesson.
0:11:22 > 0:11:27Some even look like they're starting to get the hang of it all.
0:11:27 > 0:11:31But this little guy - well, he's just not having it.
0:11:31 > 0:11:34So in the end, there's nothing for it, but to just pick him up
0:11:34 > 0:11:36and dunk him in the water.
0:11:39 > 0:11:42Oh, my God.
0:11:53 > 0:11:55All of the otters here are given names as cubs,
0:11:55 > 0:11:57to help any scientist studying them.
0:11:57 > 0:12:01And it seems only fitting to give this little guy a name
0:12:01 > 0:12:06appropriate to Lake Salvador, so I call him Dali.
0:12:24 > 0:12:28It's hard to count, but it looks like there are six tiny cubs,
0:12:28 > 0:12:30which is a record number!
0:12:36 > 0:12:37Diablo and mum, Sophia,
0:12:37 > 0:12:42are doing the bulk of the caring for the cubs at this age.
0:12:43 > 0:12:46They are helped out by the older brothers and sisters,
0:12:46 > 0:12:48but even then, they will have their work cut out,
0:12:48 > 0:12:51because six is such an unusually large family.
0:12:56 > 0:12:59Well, you know, it makes you wonder actually,
0:12:59 > 0:13:04how Diablo and the others are going to keep six cubs alive in this lake.
0:13:10 > 0:13:14It's actually something that worries me.
0:13:17 > 0:13:20Giant otters might be the largest of all the otters,
0:13:20 > 0:13:24but they do have an arch enemy here on the lake.
0:13:24 > 0:13:30A predator that kills more otters and their cubs than any other.
0:13:30 > 0:13:34And I'm heading out into the night to find it.
0:13:39 > 0:13:40It's got properly dark now
0:13:40 > 0:13:44and suddenly there are just eyes everywhere when I shine my torch.
0:13:57 > 0:14:01My boat appears to be surrounded by black caiman.
0:14:01 > 0:14:06These guys can grow huge - up to 18 feet long!
0:14:06 > 0:14:10They're the largest predator in the Amazon Basin.
0:14:10 > 0:14:13Those great big eyes are adapted to seeing in low light
0:14:13 > 0:14:16and they've got a very acute sense of hearing,
0:14:16 > 0:14:20which makes them perfectly suited to hunt in the dark.
0:14:22 > 0:14:26It's quite astonishing, really, just how many caiman we're seeing.
0:14:26 > 0:14:30I thought we might see, you know, one or two,
0:14:30 > 0:14:34but there are, literally, caiman everywhere.
0:14:38 > 0:14:41Caiman are essentially ambush hunters.
0:14:41 > 0:14:44What they do is they sit in places like this,
0:14:44 > 0:14:49just along the edges of the lake, and wait.
0:14:49 > 0:14:51And they can wait and wait and wait.
0:14:51 > 0:14:54I mean, they're in no hurry to get fed.
0:14:54 > 0:14:56This is why they're such a threat to the otters.
0:14:56 > 0:14:59Lurking in the bushes around the edge of the lake,
0:14:59 > 0:15:01waiting for any prey to swim past.
0:15:04 > 0:15:08There are over 700 black caiman on this lake,
0:15:08 > 0:15:12so they're obviously doing very well here.
0:15:12 > 0:15:15Diablo and his family are going to have to be super-cautious
0:15:15 > 0:15:17to keep those cubs alive.
0:15:34 > 0:15:38The next morning, Diablo and the other otters are all by the den.
0:15:38 > 0:15:42Something's going on. They look anxious.
0:15:44 > 0:15:47There's a great big caiman not far from the entrance.
0:15:51 > 0:15:52The cubs are inside,
0:15:52 > 0:15:56but Diablo's not going to tolerate any caiman this close to them.
0:16:09 > 0:16:11The caiman stands its ground.
0:16:14 > 0:16:18This is where having a large family pays off.
0:16:18 > 0:16:20Diablo leads the family in.
0:16:22 > 0:16:25The gang encircle the caiman, intimidating it.
0:16:31 > 0:16:35And Sophia, there she is, moves in to distract it from the front
0:16:35 > 0:16:40giving Diablo the chance to bite the caiman right on the end of the tail.
0:16:59 > 0:17:01Most caiman will bow out like this,
0:17:01 > 0:17:05when faced with a whole family of giant otters.
0:17:05 > 0:17:08The dangerous ones are those that refuse to move.
0:17:15 > 0:17:19There is another predator around here that Diablo and his family
0:17:19 > 0:17:21just wouldn't dare stand up to.
0:17:22 > 0:17:26Few of its victims ever even see it coming.
0:17:28 > 0:17:32And on our way back to camp, I stumble across evidence of one,
0:17:32 > 0:17:35just a stone's throw from Diablo's family den.
0:17:40 > 0:17:45Look at this. This is amazing. These are jaguar footprints.
0:17:45 > 0:17:50And it's got out the water and it's walked along this beach
0:17:50 > 0:17:54and it's done that in the last five minutes. These are still wet.
0:17:54 > 0:17:59That's wet sand, and in this hot sun that would have dried out.
0:18:02 > 0:18:05Quite daunting and quite exciting
0:18:05 > 0:18:11to know that there's a jaguar who almost definitely knows we're here,
0:18:11 > 0:18:13just up ahead.
0:18:19 > 0:18:21Not quite sure why
0:18:21 > 0:18:27I'm following jaguar prints that are just minutes old,
0:18:27 > 0:18:32but I have to say it's very exciting.
0:18:32 > 0:18:36Just amazing to know that within a few hundred metres
0:18:36 > 0:18:41of where I am now is a massive cat.
0:18:44 > 0:18:46That's pretty awesome.
0:18:51 > 0:18:56To me, the jaguar is the ultimate forest hunter.
0:18:56 > 0:18:59If one doesn't want to be seen, well, then, it won't be.
0:18:59 > 0:19:03It's quite unnerving to know that a jaguar's living this close
0:19:03 > 0:19:06to Diablo and the cubs.
0:19:06 > 0:19:09So I'm putting out a camera trap, right outside the otters' den,
0:19:09 > 0:19:13just in case the jaguar decides to target the family.
0:19:18 > 0:19:22But as we head off, we find signs of an even greater predator
0:19:22 > 0:19:26than the jaguar and it's hunting only metres from the den.
0:19:28 > 0:19:31This isn't the path of an animal.
0:19:34 > 0:19:37It's the path of an uncontacted tribe.
0:19:39 > 0:19:44And German, in front of me, can see this path,
0:19:44 > 0:19:48which is just the odd snapped stick, which you know,
0:19:48 > 0:19:54in a forest, which to me is just a massive tangle of broken sticks,
0:19:54 > 0:19:58and he can follow it through, by seeing all these snapped off ends.
0:19:58 > 0:20:02He can spot them really well. I mean, he can just follow this path.
0:20:02 > 0:20:05To me, you know, we're not on a path. There's nothing on the ground.
0:20:05 > 0:20:10But he's navigating us through the forest.
0:20:10 > 0:20:14Look, there's another one, been snapped off.
0:20:14 > 0:20:18My guides, Juan Andres and German explain that it's the path
0:20:18 > 0:20:22of a hunting party from the uncontacted Mashco-Piro tribe.
0:20:22 > 0:20:26The broken twigs are their way of navigating through the forest.
0:20:29 > 0:20:34So three guys with bows and arrows sneaking through the forest here.
0:20:34 > 0:20:36If they're hunting here, I'm worried.
0:20:36 > 0:20:38Might they go for the otters?
0:20:38 > 0:20:45Nothing from the river. Normally just turtle eggs, but no fish, no.
0:20:45 > 0:20:49Nothing from... Just the turtle eggs and peccaries mainly.
0:20:49 > 0:20:51Does he think they might...
0:20:51 > 0:20:55Maybe they've seen us and we haven't seen them?
0:21:02 > 0:21:05No, these are old marks.
0:21:05 > 0:21:07They're old. Oh, OK.
0:21:08 > 0:21:10Diablo and the cubs live on a lake
0:21:10 > 0:21:13that's clearly within the tribe's hunting ground.
0:21:13 > 0:21:17So it's a real relief to learn that they're not on the menu.
0:21:24 > 0:21:28The forests here might be the domain of the Mashco-Piro hunters,
0:21:28 > 0:21:33but out on the lake, Diablo and his family are in charge.
0:21:33 > 0:21:34And when it comes to hunting,
0:21:34 > 0:21:39there aren't many fishermen who can catch fish as fast as a giant otter.
0:21:43 > 0:21:46The family seem to spend their whole time fishing.
0:21:48 > 0:21:50I can't believe they never get full.
0:21:55 > 0:21:58But then, a fully-grown giant otter does need
0:21:58 > 0:22:01around four kilos of fish a day.
0:22:13 > 0:22:17What that means is that the most infamous fish of them all
0:22:17 > 0:22:22is at the top of the menu - the piranha.
0:22:22 > 0:22:25Look at the size of this fish.
0:22:25 > 0:22:30Now that is a piranha. Wow.
0:22:32 > 0:22:37Very proud of himself. That is good work.
0:22:37 > 0:22:39Piranhas are really common on the lake
0:22:39 > 0:22:41and Diablo and the others seem to love them.
0:22:41 > 0:22:45It makes me wonder though - how can he teach his cubs to take them on
0:22:45 > 0:22:48without getting bitten by those razor-sharp teeth?
0:22:53 > 0:22:57I've decided to try and see just how aggressive those piranhas are,
0:22:57 > 0:23:01by attaching a chunk of meat to an underwater camera.
0:23:12 > 0:23:17Ooh, now there's a fish. Ooh, there's a fish.
0:23:17 > 0:23:21No, that's a piranha. And another one.
0:23:23 > 0:23:27They just pile in, grab it, rip it up, and swim off.
0:23:27 > 0:23:31One went in and started and now all the others have started piling in,
0:23:31 > 0:23:32they're really going for it.
0:23:35 > 0:23:37Those piranhas move really fast.
0:23:37 > 0:23:39They've got a very acute sense of smell,
0:23:39 > 0:23:41so that's why they can find meat so quickly.
0:23:41 > 0:23:45What fascinates me though is how frenzied they are at devouring it.
0:23:45 > 0:23:47Less than 30 seconds!
0:23:48 > 0:23:52I am amazed at the speed they've torn that piece of meat apart.
0:23:55 > 0:23:57Those cubs will have to move at lightning speed,
0:23:57 > 0:24:00to catch their dinner without getting bitten.
0:24:00 > 0:24:03It's a skill they're going to have to learn.
0:24:07 > 0:24:09You've got to admire those otters
0:24:09 > 0:24:12because they swim around in this all day long,
0:24:12 > 0:24:16and I don't even want to dangle my feet off the end any more.
0:24:35 > 0:24:37Swimming lessons for Dali and the other cubs
0:24:37 > 0:24:41are now a daily event here on the lake.
0:24:41 > 0:24:44And although they're not the best of swimmers,
0:24:44 > 0:24:47the cubs are finally starting to get the hang of it.
0:24:59 > 0:25:02Moments like this are a really good chance
0:25:02 > 0:25:06for the older brothers and sisters to help out, get to know the cubs.
0:25:30 > 0:25:34They do all sometimes get a little bit over-excited.
0:25:34 > 0:25:37So Diablo and Sophia have to step in, occasionally,
0:25:37 > 0:25:39and rescue the little ones.
0:25:43 > 0:25:45Building these family bonds is crucial,
0:25:45 > 0:25:47because they need to be able
0:25:47 > 0:25:50to depend on each other, in times of danger.
0:26:05 > 0:26:09And as for little Dali, well, I can see mum Sophia
0:26:09 > 0:26:12trying to take him off to one side
0:26:12 > 0:26:15so he can get some practise in peace.
0:26:24 > 0:26:26He's nearly swimming unaided now,
0:26:26 > 0:26:29just about keeping his head above water.
0:27:00 > 0:27:03A few weeks have passed.
0:27:03 > 0:27:08More and more, I'm noticing a build-up of caiman near the den.
0:27:08 > 0:27:11I'm not sure whether this is from the smell of the latrine,
0:27:11 > 0:27:15which is really starting to stink now,
0:27:15 > 0:27:18or whether the hunting's just better down this end of the lake.
0:27:27 > 0:27:30There's one large caiman in particular
0:27:30 > 0:27:33they just can't seem to shift.
0:27:35 > 0:27:40So today, they've clearly decided to do something about it - move den.
0:27:43 > 0:27:47Diablo and Sophia have a cub each and the rest of the family
0:27:47 > 0:27:50are flanking them in one big protective group.
0:27:58 > 0:28:00They're going a really long way.
0:28:00 > 0:28:04I mean, they've been going for ages, right down the centre
0:28:04 > 0:28:07and I guess that's cos the caiman are going to be on the edges
0:28:07 > 0:28:10and they're really vulnerable when they're like this
0:28:10 > 0:28:11having those cubs out.
0:28:11 > 0:28:13Even when everyone's backing each other up,
0:28:13 > 0:28:16moving like this is a risky business.
0:28:16 > 0:28:20Yeah, I can see several caiman along the edges.
0:28:22 > 0:28:26And although these guys are essentially ambush hunters,
0:28:26 > 0:28:29they're also big opportunists,
0:28:29 > 0:28:34so if they see any weakness, they'll go for it and exploit it.
0:28:34 > 0:28:37So these otters have got to be careful.
0:28:37 > 0:28:38It's the middle of the day
0:28:38 > 0:28:41so the otters are banking on the caiman being less active.
0:28:45 > 0:28:48All the other members of the family are coming together.
0:28:53 > 0:28:58This is where having a big family, being a social animal,
0:28:58 > 0:29:02really comes into its own, because this family is now working
0:29:02 > 0:29:07as a single unit, to shift those cubs from one den to the other.
0:29:12 > 0:29:14OK, so things are looking good.
0:29:14 > 0:29:20They've got four cubs across now, which is good.
0:29:22 > 0:29:25As long as everyone sticks together, these cubs should be safe.
0:29:28 > 0:29:30But then something odd happens.
0:29:30 > 0:29:33One of the otters, I think it's Diablo,
0:29:33 > 0:29:35has been back to the den alone.
0:29:35 > 0:29:39It seems he's the only one who's remembered the two missing cubs.
0:29:45 > 0:29:47Now, that is just dangerous.
0:29:47 > 0:29:53They're really vulnerable now, carrying that cub on its own.
0:29:53 > 0:29:57They need the family. They need the protection of everyone else.
0:29:57 > 0:29:59Shouldn't be doing this on its own.
0:29:59 > 0:30:02I'm not sure whether he's brave or just taking too big a risk.
0:30:06 > 0:30:09I can see a caiman really close.
0:30:12 > 0:30:15Just got to steer clear of there.
0:30:18 > 0:30:22Just easy pickings for a caiman.
0:30:25 > 0:30:29Because to defend itself, the otter has to drop the cub.
0:30:35 > 0:30:36This is actually quite dodgy
0:30:36 > 0:30:39because this otter is really vulnerable now.
0:30:59 > 0:31:05Come on, where are you? Where are you?
0:31:05 > 0:31:07There! Ha-ha!
0:31:07 > 0:31:10Good old Diablo, what a dude!
0:31:16 > 0:31:18Hold on, what's that?
0:31:18 > 0:31:20There's two cubs.
0:31:22 > 0:31:25That's bizarre. He's carrying two.
0:31:25 > 0:31:30He only had one in his mouth. That's amazing!
0:31:31 > 0:31:33He's gone up.
0:31:33 > 0:31:37He must have had one in his mouth and been carrying the other one.
0:31:39 > 0:31:42I've never seen an otter carrying two cubs.
0:31:46 > 0:31:49He must just be swapping, juggling, you know.
0:31:49 > 0:31:53Holding one in his mouth and the other one in his front paws maybe,
0:31:53 > 0:31:57and then swapping them allowing them to breathe.'
0:32:04 > 0:32:08I'm very relieved that all six cubs have made it back to the den.
0:32:12 > 0:32:16SCREECHING AND SCREAMING
0:32:20 > 0:32:22But then all hell breaks loose.
0:32:26 > 0:32:29I don't know what's going on in here.
0:32:29 > 0:32:33Like, all I can hear is just the loudest screaming and shouting.
0:32:33 > 0:32:37They're just... I've never heard them squeal that loudly.
0:32:37 > 0:32:39There must be a fight going on.
0:32:39 > 0:32:44It sounds to me like something's kicked off with a caiman
0:32:44 > 0:32:47and they're all getting involved.
0:32:47 > 0:32:51The vegetation's so thick here, it's impossible to see what's happening.
0:32:53 > 0:32:56It's so frustrating. I just want to see it.
0:33:00 > 0:33:03Just after the commotion ends, a caiman slips out of the forest.
0:33:11 > 0:33:14The family slowly reappears in dribs and drabs.
0:33:14 > 0:33:17But something doesn't feel right.
0:33:19 > 0:33:20Dali looks like he's OK,
0:33:20 > 0:33:24but I'm pretty sure two of the cubs are missing.
0:33:25 > 0:33:29They must have been killed by the caiman during the fight.
0:33:32 > 0:33:35It's so sad.
0:33:35 > 0:33:40And to me, I guess it's because I got really fond of them,
0:33:40 > 0:33:42I got to know them.
0:33:42 > 0:33:46But what's worse about it, what's more tragic, is that
0:33:46 > 0:33:51the giant otter population can't afford to lose two cubs like that.
0:33:51 > 0:33:55They're just, they're rare, and they needed them.
0:33:55 > 0:33:57And it all just seemed so pointless.
0:33:58 > 0:34:02But I guess that's just the way things are on this lake.
0:34:11 > 0:34:15Diablo's success now rests with the four remaining cubs.
0:34:27 > 0:34:31By mid-February, the cubs are growing up fast.
0:34:33 > 0:34:36They're all now getting pretty confident in the water
0:34:36 > 0:34:39and even Dali's swimming like a pro.
0:34:42 > 0:34:44It's lovely seeing him out of the water
0:34:44 > 0:34:47playing with his old dad Diablo, like this.
0:34:47 > 0:34:51He looks like a very well-fed, healthy young otter.
0:34:52 > 0:34:56One of the main reasons everyone's doing so well here
0:34:56 > 0:34:59is that the lake's very rich in nutrients,
0:34:59 > 0:35:02which makes it absolutely jam-packed full of fish.
0:35:03 > 0:35:05And where there's fish,
0:35:05 > 0:35:09there's always a load of fishermen lining up to catch them.
0:35:21 > 0:35:26Some with eyes bigger than their beaks.
0:35:42 > 0:35:45At four months old, Dali and the other cubs
0:35:45 > 0:35:49can only really watch the fishing.
0:35:50 > 0:35:53They're getting more confident in the water,
0:35:53 > 0:35:55but they've got a long way to go
0:35:55 > 0:35:57before they can catch their own fish.
0:35:57 > 0:36:01They're still very young and vulnerable, but if they make it
0:36:01 > 0:36:04through the next few months and learn to fish for themselves,
0:36:04 > 0:36:07they've got a good chance of making it to adulthood.
0:36:11 > 0:36:15For now, they're still relying on the rest of the family for food,
0:36:15 > 0:36:19but to get it, they've got to beg.
0:36:19 > 0:36:22And Dali, in particular, seems the most persistent.
0:36:37 > 0:36:42Although Diablo's not going to give up his breakfast that easily.
0:36:46 > 0:36:50Fishing plays such an important role in the otters' lives
0:36:50 > 0:36:55and I find it so frustrating that most of it goes on out of sight.
0:36:55 > 0:36:58So I've come up with a simple invention -
0:36:58 > 0:37:02one small waterproof camera taped to my water bottle.
0:37:02 > 0:37:06And what I want to do with this device is stick it in the water
0:37:06 > 0:37:10and then bank on the otters', sort of, natural curiosity,
0:37:10 > 0:37:12and hope they'll come up and have a look at it
0:37:12 > 0:37:15and I'll then get a decent look at them underwater.
0:37:38 > 0:37:41You can really see the size of the webs on their feet.
0:37:41 > 0:37:43They're almost like flippers.
0:37:46 > 0:37:51In this muddy water, my bottle cam can't film very much
0:37:51 > 0:37:53but it does remind me of the only other time
0:37:53 > 0:37:56I've filmed these animals underwater.
0:37:56 > 0:38:01Back then, I got some great pictures of their amazing swimming abilities.
0:38:01 > 0:38:06So fast and able to instantly change direction to grab a fleeing fish.
0:38:11 > 0:38:15It must be the huge, flat tail that gives them such a turn of speed.
0:38:24 > 0:38:29Diablo's cubs are too small at the moment to move like these adults.
0:38:29 > 0:38:31They lack the power.
0:38:41 > 0:38:44Going out into the lake, watching the parents hunt,
0:38:44 > 0:38:46is how the cubs learn,
0:38:46 > 0:38:49which is why fishing trips like this, with the family,
0:38:49 > 0:38:52are now becoming a daily event.
0:38:59 > 0:39:03Dali, like the other cubs, seems to be a bottomless pit -
0:39:03 > 0:39:07he's constantly harassing the adults every time one of them gets a fish.
0:39:13 > 0:39:16He can't swim and eat at the same time, though,
0:39:16 > 0:39:19so he's got to go ashore with his prize.
0:39:23 > 0:39:25The problem with that is that now he keeps going missing
0:39:25 > 0:39:28in the bushes along the edge of the lake.
0:39:32 > 0:39:36Today, the family's chased fish right up the lake,
0:39:36 > 0:39:40and it looks like poor old Dali's been left well and truly behind.
0:39:50 > 0:39:52Yeah, I hope there aren't any caiman about,
0:39:52 > 0:39:54cos he's really squeaking.
0:39:54 > 0:39:55DALI GIVES A HIGH-PITCHED SQUEAK
0:39:55 > 0:39:57And if any caiman hear that...
0:39:58 > 0:40:00..they'll go in for him,
0:40:00 > 0:40:03cos he's really vulnerable on his own like that.
0:40:09 > 0:40:11Oh, I can see one in the bushes...
0:40:11 > 0:40:13but he's not moving.
0:40:15 > 0:40:18The family have realised Dali's missing -
0:40:18 > 0:40:20they're all calling out to him.
0:40:21 > 0:40:24SQUEAKS AND GRUNTS
0:40:28 > 0:40:30They are a bit dopey sometimes,
0:40:30 > 0:40:33cos they're all screeching their heads off,
0:40:33 > 0:40:35but they're never waiting to listen for a reply.
0:40:39 > 0:40:41CALLS CONTINUE
0:40:42 > 0:40:46The family all head back to the area where they last saw Dali.
0:40:46 > 0:40:49DALI SQUEAKS
0:40:57 > 0:40:58SQUEAKING
0:41:00 > 0:41:04It's a relief when Diablo finally spots his son.
0:41:09 > 0:41:12I love it when they greet each other.
0:41:12 > 0:41:14There is definitely affection there.
0:41:14 > 0:41:17It's definitely, you know... They're pleased to see each other.
0:41:34 > 0:41:36Earlier in the season,
0:41:36 > 0:41:39I put a camera trap out in front of the family den,
0:41:39 > 0:41:43to try and find out if a jaguar might be hunting in the area.
0:41:44 > 0:41:48I reckon it's time to have a look and see if it's filmed anything.
0:41:52 > 0:41:56There's the otters outside the den.
0:41:56 > 0:41:58Probably getting ready for bed.
0:41:58 > 0:42:03And then out of the darkness emerges a cat I never thought I'd see.
0:42:03 > 0:42:06Look, look at that! Oh!
0:42:06 > 0:42:10Not a jaguar, but an ocelot.
0:42:10 > 0:42:13I've never seen an ocelot in the wild.
0:42:13 > 0:42:15They're mostly nocturnal hunters
0:42:15 > 0:42:18and, given half the chance, they'd take an otter cub.
0:42:18 > 0:42:22The fact that there are predators like this ocelot on the prowl
0:42:22 > 0:42:25is probably why the otters are out during the day
0:42:25 > 0:42:28and tucked away in the safety of the den at night.
0:42:28 > 0:42:32Watching a shot of an ocelot like that is pretty special.
0:42:32 > 0:42:34Well, that was worth putting this out for.
0:42:49 > 0:42:51But then I can't believe my luck.
0:42:53 > 0:42:54There's a jaguar!
0:43:03 > 0:43:04- HE CHUCKLES - Oh, my God!
0:43:06 > 0:43:08That is stunning.
0:43:08 > 0:43:10Big male jaguar.
0:43:16 > 0:43:19That is unbelievable.
0:43:19 > 0:43:21What an incredible creature.
0:43:33 > 0:43:35What a treat.
0:43:37 > 0:43:40It's amazing to know that...
0:43:41 > 0:43:43..everywhere we walk around here...
0:43:45 > 0:43:48..these massive cats are also wandering around.
0:43:50 > 0:43:54And I bet they see us all the time.
0:43:57 > 0:43:59There he goes.
0:44:03 > 0:44:04Well done there, man.
0:44:08 > 0:44:10That was a BIG animal.
0:44:12 > 0:44:16It's pretty awe-inspiring to see a massive jaguar like that.
0:44:16 > 0:44:19But knowing that they're living and hunting so close to the otters
0:44:19 > 0:44:25does worry me. Not just for Diablo and his family, but also myself.
0:44:31 > 0:44:36I've been watching the giant otters for nearly four months now.
0:44:36 > 0:44:38And what's impressed me most about them
0:44:38 > 0:44:41is just how nice they are to each other.
0:44:41 > 0:44:43Yeah, they get a bit boisterous occasionally,
0:44:43 > 0:44:45but it's all good fun.
0:44:45 > 0:44:47SQUEAKING
0:44:50 > 0:44:55They seem to me to be a really happy, tight-knit family.
0:44:57 > 0:45:00Even if old Diablo likes to slip away
0:45:00 > 0:45:03for a bit of peace and quiet every now and then.
0:45:08 > 0:45:11Dali's gone from strength to strength
0:45:11 > 0:45:13and he's really starting to explore the world.
0:45:21 > 0:45:23But the large caiman's back again.
0:45:40 > 0:45:43As usual, it seems to be lurking right by the den.
0:45:46 > 0:45:49The otters are on high alert.
0:45:49 > 0:45:50They all want to keep him in sight.
0:45:52 > 0:45:54Diablo seems especially twitchy.
0:45:57 > 0:46:00The caiman's blocking the way to the den.
0:46:03 > 0:46:07The cubs are in the water, so no-one's taking any chances.
0:46:10 > 0:46:13The caiman has to be moved on.
0:46:22 > 0:46:25All the adults move in to harass it.
0:46:31 > 0:46:33The cubs keep their distance.
0:46:38 > 0:46:41Sophia goes in at the front, sizing up the caiman.
0:46:44 > 0:46:47THE OTTERS SNORT
0:47:00 > 0:47:03Others move in to try to distract it,
0:47:03 > 0:47:07giving Diablo his chance to go for the tail.
0:47:17 > 0:47:20But the caiman still won't budge.
0:47:24 > 0:47:25Then it goes for him.
0:47:27 > 0:47:30THE OTTERS CALL IN ALARM
0:47:49 > 0:47:54The cubs panic and follow the adults right into the middle of the fight.
0:48:10 > 0:48:15By the time the caiman realises that it's outnumbered, it's too late.
0:48:15 > 0:48:16The otters step it up.
0:48:26 > 0:48:29They overpower the caiman, some holding it down,
0:48:29 > 0:48:30others biting it in the head.
0:48:43 > 0:48:46After an hour of fighting, it's all over.
0:49:02 > 0:49:07The caiman may be dead, but I need to know if the otters are all OK.
0:49:11 > 0:49:16It doesn't take long to realise two of the cubs are missing.
0:49:20 > 0:49:23It's kind of hard when you...
0:49:23 > 0:49:27when you...see an event like that, because on the one hand
0:49:27 > 0:49:31it's, you know, undoubtedly an incredible thing to see.
0:49:31 > 0:49:37You know, giant otters taking on a caiman...and winning!
0:49:37 > 0:49:40But on the other hand, you know, we lost two cubs.
0:49:46 > 0:49:48I find that really hard because...
0:49:49 > 0:49:51..I've watched these cubs since they were tiny.
0:49:51 > 0:49:53You know, just a few weeks old.
0:50:01 > 0:50:03And you know, they'd done really well.
0:50:03 > 0:50:06They'd got, you know, they'd gone so far.
0:50:06 > 0:50:09And then to see the caiman killing them...
0:50:11 > 0:50:15Well, it kind of, it was a moment that destroyed the whole family.
0:50:16 > 0:50:17And...
0:50:20 > 0:50:24..I guess that's why they went from this,
0:50:24 > 0:50:29you know, loving family - happy, playing around, fishing -
0:50:29 > 0:50:35to these angry, furious killing machines.
0:50:36 > 0:50:40Biting it in the head, ripping it apart underneath,
0:50:40 > 0:50:44at huge risk to their own lives,
0:50:44 > 0:50:51in order to, I guess, kill the thing and eliminate it from the lake.
0:50:51 > 0:50:55You know, that caiman was a threat to their family
0:50:55 > 0:50:56and they had to get rid of it.
0:51:16 > 0:51:18THUNDER CRACKS
0:51:22 > 0:51:25WATER DRIPS
0:51:37 > 0:51:42A week after the fight, the rainy season finally kicks in.
0:51:45 > 0:51:48I haven't seen the otters for days
0:51:48 > 0:51:51and can't be sure which cubs are still alive.
0:51:55 > 0:51:58There's just no let up in the weather -
0:51:58 > 0:52:01the lake and surrounding forests are completely flooded out.
0:52:10 > 0:52:14The downpours are torrential and they're not stopping.
0:52:14 > 0:52:18It's making just travelling through the forest almost impossible.
0:52:26 > 0:52:28THUNDER BOOMS
0:52:37 > 0:52:41Our camp's now flooded out and our equipment's starting to fail.
0:52:45 > 0:52:48We've got no choice but to evacuate.
0:53:04 > 0:53:07THUNDER CRACKS
0:53:20 > 0:53:23A month later, the weather's better
0:53:23 > 0:53:26and I'm travelling back upriver to look for the otter family.
0:53:29 > 0:53:30I'm apprehensive, though.
0:53:30 > 0:53:33I've no idea if Dali's alive.
0:53:33 > 0:53:36I don't even know if the family's living on the lake anymore.
0:53:38 > 0:53:40OTTERS SQUEAK
0:53:40 > 0:53:43So I'm very relieved when I hear the familiar shrieks.
0:53:48 > 0:53:52But before I get too excited, I want to know who's left.
0:53:56 > 0:54:00It looks, from what I'm seeing here, there's only six.
0:54:03 > 0:54:07Sadly, there's no sign of my old friend, Diablo.
0:54:14 > 0:54:17But of the otters I CAN see here,
0:54:17 > 0:54:20two in particular are of real interest.
0:54:22 > 0:54:25I can see there's two cubs left.
0:54:25 > 0:54:29I mean, they don't look like cubs any more. Probably that big?
0:54:30 > 0:54:33And one of them is Dali.
0:54:45 > 0:54:47I spend the morning with the otters
0:54:47 > 0:54:49and follow them as they head off fishing.
0:54:57 > 0:55:00The two cubs have really grown since I last saw them.
0:55:00 > 0:55:03They're so much bigger and bolder now.
0:55:05 > 0:55:08Dali might still be smaller than the others,
0:55:08 > 0:55:10but he's got real attitude,
0:55:10 > 0:55:13and seems to love throwing his weight around.
0:55:24 > 0:55:29It amazes me that these two cubs have managed to survive so long.
0:55:29 > 0:55:32I've seen the odds they face.
0:55:32 > 0:55:36But there's still one big hurdle I want to see them overcome.
0:55:43 > 0:55:45That's the cub. He's caught his own fish.
0:55:48 > 0:55:49He's got his own fish!
0:55:54 > 0:55:56That's a major breakthrough.
0:55:56 > 0:56:01That's the first time I've seen one of the cubs catch their own fish.
0:56:03 > 0:56:08And that is a major life moment for an otter cub,
0:56:08 > 0:56:10not to be fed by Mum and Dad,
0:56:10 > 0:56:13not to go and steal a fish off another otter,
0:56:13 > 0:56:19but to actually catch its own fish finally means it can feed itself.
0:56:22 > 0:56:27That's like the last major hurdle
0:56:27 > 0:56:31going from childhood into adulthood for an otter,
0:56:31 > 0:56:35is to catch its own fish and he's just done it.
0:56:50 > 0:56:53These cubs when I met them, they were this big.
0:56:53 > 0:56:56They were totally helpless, totally useless,
0:56:56 > 0:56:59totally dependent on Mum and Dad and the family
0:56:59 > 0:57:00to do everything for them.
0:57:00 > 0:57:05And now they're proper otters, they're six months older.
0:57:05 > 0:57:07You know, and they're catching fish.
0:57:07 > 0:57:12And that means that their chances of survival have just skyrocketed.
0:57:15 > 0:57:20And then I'm relieved to see a familiar face.
0:57:29 > 0:57:31It's Diablo.
0:57:33 > 0:57:38It's down to this devoted father that the cubs have made it this far.
0:57:40 > 0:57:44And if they can go on to be even half as prolific as their dad,
0:57:44 > 0:57:49the giant otter population here in Manu will be in good hands.
0:57:51 > 0:57:55In a place like Manu, which is one of the last strongholds
0:57:55 > 0:58:00of these incredibly rare animals, that's hugely important
0:58:00 > 0:58:06that we've just got two new otters into that population.
0:58:07 > 0:58:11And that's a lovely thing to have sat here
0:58:11 > 0:58:13and witnessed over the last six months.
0:58:36 > 0:58:39Subtitles by Red Bee Media Ltd