Steve voice-over: I'm Steve Backshall, a naturalist and explorer.

♪ Aah!

♪ Ahh.

I've come to Russia to take on a first descent of an unexplored river.

♪ This is Kamchatka.

It's home to some of the most extraordinary wilderness found anywhere on the planet, and our team is going to attempt to become the first ever to paddle this river from source to sea.

♪ This river will take us deep into a land packed with more brown bears than anywhere else on the planet.

♪ Out here in the wilderness, there is no one.

In terms of adventure, this is one of the most exciting places on the planet.

We're heading into a forgotten world, a pristine wilderness untouched by humans.

♪ That is a giant bear.

♪ Steve, voice-over: Kamchatka.

A remote territory in the far east of Russia.

♪ One of the most spectacular but least populated places on earth.

♪ Almost all of its 400,000 inhabitants live in the capital city-- Petropavlovsk.

[Men speaking Russian] Helicopters are always really important to us on expeditions, but this is something else.

It's a Russian MI-8, which used to be, in the Soviet era, a real military workhorse, but they've been kind of repurposed now, and here in Kamchatka, this is kind of the only way of getting around.

Come check this out.

The payload on this thing is about 4 tons, which means that if you could get it inside, it could fly away with a fully-grown elephant.

So, I'm pretty sure it's gonna have room for all of us, our kayaks, and most importantly, my food.

On this expedition, I've assembled a team of world-class kayakers.

♪ In over 20 years of doing trips like this, this is probably the strongest team I've ever had.

Georgie and James are both international-quality athletes.

Tom and Sal, who are both professional kayakers, some of the best in the business.

And me.

♪ ♪ Steve, voice-over: We're flying north, along the volcanic spine of the peninsula, into a landscape untouched by human hands.

♪ 11 time zones and nearly 7,000 kilometers away from Moscow, the Kamchatka Peninsula is virtually cut off from the rest of Russia.

We're heading to the Kronotsky Reserve, a protected wilderness stretching for over 10,000 square kilometers.

♪ We want to kayak the length of the Kronotsky River, 40 kilometers through pristine bear habitat, to the Pacific Ocean.

♪ This is our first glimpse of our river.

For months now, we've been poring over satellite imagery and seeing it from high, high up, and this is the first time we've seen it for real.

♪ Look at that.

♪ This is an incredibly productive salmon spawning river.

Thousands and thousands of fish heading upriver to spawn, and wherever you've got that amount of protein, you're bound to find predators, and somewhere like this, completely untouched, completely unspoiled by human beings, is a real rarity in the modern world.

♪ Bear!

Bear!

Unbelievable!

If you can see them from up here, what's it gonna be like down there?

♪ Steve, voice-over: Many of these bears will never have seen humans before.

♪ But to reach them, we have to brave this ferocious and unpredictable river.

♪ Tom McClay is a professional kayaker and paramedic.

As our head of safety, it's his job to identify potential evacuation sites.

There's a harbor over here.

[Speaking indistinctly] Is that a potential landing site?

Tom: Down on the island.

♪ This looks to me like some of the most full-on white water that I will ever have tried to paddle.

♪ It's nonstop.

There's no way of getting out.

♪ And there's several big drops, like that there.

♪ Yeah, that is intense.

This is gonna be massive.

♪ Steve, voice-over: Our expedition starts at a research outpost on the shores of Lake Kronotsky at the head of the river.

♪ Oh, my--look at that!

That is jaw-dropping.

I wasn't expecting it to feel so close.

♪ Wow.

♪ So, I guess we're gonna take them down to the end of the lake?

Kayaks we can just carry just on back.

OK. Steve, voice-over: This expedition would be impossible without our Russian guide Sergey Lukin.

[Speaking Russian] Steve, voice-over: Sergey is an authority on Kamchatka's wilderness, but even he has never been down this river.

♪ It's just time for us to check every rapids.

It's really dangerous and I hope everything will be good.

♪ Steve, voice-over: It's October, and that means short days, unpredictable weather, and temperatures below freezing.

Oh, it's cold.

Ha!

♪ This was a rookie error.

I should've left all of this stuff inside.

♪ Steve, voice-over: Ahead of us lies 40 kilometers of unexplored river.

A first descent into untouched wilderness.

♪ To make it down in one piece, I'm putting my trust in lead kayaker Sal Montgomery.

Montgomery: Whitewater's a very dynamic sport, so, you're constantly reacting to what's happening, and obviously, if you're tired or not feeling so well, your reactions are basically gonna be much slower and you're more likely to make mistakes, and in whitewater like this, a small mistake can escalate quite quickly and cause big problems.

Steve, voice-over: Freestyle kayaker Georgie Preston competes for the army.

It's not whitewater that worries her.

It's bears.

Particularly as we've seen from the helicopter going down this first section, it's really dense vegetation at the side of the river, so, pushing through that, the chances of surprising a bear are quite high, and a surprised bear, particularly a mother with cub, is the most dangerous.

Georgie: Steve, um, do bears sense fear?

Steve: Yeah, so, that's one of the reasons why, you know, if you do, by any chance, come into encounter with one, do not run.

Just be calm and confident.

Just talk to the bear.

"Hello, Mr. Bear.

How you doing?

I'm fine.

I'm just gonna walk away now."

It's not that he can understand you, but the tone of your voice will be important to sort of just placating and comforting the animal.

I know it sounds nuts, but it does work.

[Group chuckling] ♪ Steve, voice-over: Capturing all the action on the whitewater is James Bebbington.

♪ All your kayak cams going?

Woman: Yes.

James: Cool.

We will see what's happened.

Sal: All good?

Sergey: You have to be a professional kayaker because it's--I hope we have some.

[Chuckles] [Laughter] Georgie: You're making it look really good.

There's no dignity in this sport, is there?

Sal: Here we go.

♪ Steve: The most special thing about any expedition is that sense of the unknown, of doing something, going somewhere that nobody ever has before.

And I feel that now.

♪ I see white!

Our first rapids already.

♪ Oh!

That water's really cold!

Georgie: Oh!

So cold!

Steve, voice-over: This unexplored river is our pathway into the heart of brown bear territory.

♪ The Kronotsky River cascades 40 kilometers through a landscape of volcanic rock.

We're anticipating 5 days of hard paddling.

Our first camp will be upstream of any serious whitewater.

♪ Tom: So, you've got that nice speedway into the river, and then below that, there's that crashing wave.

Steve, voice-over: To run a first descent, each kayaker takes on a different role.

♪ As safety kayaker, Tom goes first, with James close behind.

Sal goes next, and I follow her line through the rapid.

And Georgie brings up the tail.

♪ ♪ Ee-ooh!

Steve, voice-over: We're getting into a rhythm with our kayaks, but we've not worked out what to do when we see a bear.

I know you used to use this one for monkey.

So, you could use, like, "Rrr!"

Ha ha!

I like it!

That's the river signal for "bear."

Arrr!

You're a pro.

You're a natural.

-Arr!

-Arr!

-Bear!

-Guys!

Steve: I don't believe it!

Amazing!

Epic!

That was incredible!

Just seconds after you said it!

And Sal didn't even know the signal!

This is paradise!

Paddling down a pure, pristine, perfect whitewater river.

Bears coming down to the river's edge.

I mean, this could not be more perfect.

There cannot be many places like this left in the world.

Amazing.

♪ Steve, voice-over: Today, the Kronotsky Reserve is fully protected.

♪ But back in the Soviet era, it was surveyed for oil and hydro power.

♪ Some old surveyors' tracks remain.

♪ Sergey and the camera crew are using them to follow us down the river.

♪ They're heading 4 kilometers downstream, where, using satellite images, we've spotted the perfect campsite by the remains of an old bridge.

♪ It's an ideal place for us all to regroup.

♪ An old bridge!

This is the perfect campsite.

You all right, guys?

What'd you reckon?

Yeah, it does.

It's nice and sheltered out the wind.

Steve, voice-over: Sergey's ahead of the game, already setting up his tent for the night.

The only thing is, you know why all of this ground is flattened?

Bears.

[Laughs] Bear can be everywhere, especially on bear tracks.

We'll know we're on their food trail.

Yeah.

Well, this is probably a bear bed, actually.

[Both talking at once] Yeah.

[Laughs] Steve, voice-over: Sergey has just what we need-- an electric fence.

[Man and Sergey speaking Russian] Steve, voice-over: Camping in the middle of a bear trail like this, it's essential.

[Men speaking Russian] Yeah, this bear fence is really close to our tent.

These guys are doing a great job, but I'm really worried that I'm gonna get up in the night, little bit disorientated, come out, and stumble into it.

5.8 kilovolts.

[Indistinct chatter] Georgie: My bear plan, if a bear comes along, Sergey said just to make yourself look really big, but I think the best thing is to go and get Sergey out of bed and he can stand up to the bear for me.

Steve: It's been the perfect start, just the perfect start.

A chance to get confidence back, to paddle something big and impressive, but not too frightening.

Yeah, just get a sense of what it's like to be on a big river again.

Steve, voice-over: But we can't afford to drop our guard.

We know from the helicopter recon that from here on in, the river gets committing and intent.

♪ We've seen that a few hundred meters from our camp, the whitewater is forced into a canyon and thunders over 4 massive drops.

♪ ♪ It's absolutely epic.

Wow.

♪ Steve, voice-over: To get a closer view, we call in our drone pilot Jimmy Cape.

You can handle that one here.

Yeah, yeah.

Jimmy: [Indistinct].

[Drone whirring] ♪ A big, mean river.

Looks like there's quite a lot going off around that corner, doesn't it?

It doesn't look like it'd be possible to run these first two and then get out.

It looks like it's gonna be all or nothing.

And the fourth one is just peeling off around the corner as well, and that looks pretty significant, that one.

All of the water's constricted and it's just thundering through there at impossible volume and pace, and if you got something wrong there, you know, there is no way that you're coming out the other side.

♪ It's just that corner, isn't it?

Just that corner.

♪ Steve, voice-over: As a team, we decide this section is too dangerous to run.

We're not taking this decision lightly.

If someone were injured here, it would take at least a day to get them to somewhere where they could be evacuated by helicopter.

You know, it happens in the gorge, I mean, you're totally on your own.

There is no way anyone is coming to help you in there.

♪ Steve, voice-over: It's not a risk we can take in a landscape this remote.

♪ Our only option is to carry everything around the gorge.

♪ Rammed full of gear, our kayaks weigh about 40 kilos, and we've got a kilometer to hike before we can get back on the water.

♪ Ooh.

Look at that.

It's not difficult to figure out what the bears round here are feeding on.

Berries.

Ohh.

That's pretty much all this is, is just undigested berries.

As we get downstream, they're gonna be feasting on the salmon, and that is far, far richer in protein and fat.

This, you have to just eat almost nonstop to get enough to nourish you, and right now, they're trying to lay down fat reserves for hibernation in the winter, so, they just need to eat and eat and eat.

Uh, we just have to make sure we don't walk round the corner into any of them.

♪ Uhh.

Ahh.

♪ ♪ Steve: There it is!

We're here!

Ooh.

Let's see what we got.

♪ Georgie: We're, like, literally straight into it.

Sal: Yeah.

Man: No warming up at all.

Straight into the action.

Steve: Yeah, that's-- that's a full-on start.

♪ Steve, voice-over: There's no time to catch our breaths.

There's rocks at the bottom but the water's coming up.

Steve, voice-over: It's taken us half a day to pull our kayaks around the canyon.

And we still have hours to go to reach our next camp and rendezvous with Sergey.

♪ Man: Good to go?

Second man: Ready, yeah.

Steve, voice-over: Tom and James head down first.

Sal: Can we see George?

Steve: Yes.

♪ Steve, voice-over: We are all exhausted, but the clock is ticking.

♪ Aah!

No, come on, come on!

Bring it around.

That's it.

♪ Uhh!

Steve, voice-over: We pull our kayaks out onto a nearby island to scout the next section of whitewater.

Well, there's no letup, is there?

Um, [indistinct].

This is big.

Looking at the GPS, we're about half a kilometer from where we were gonna camp.

Steve, voice-over: After fording our kayaks around the canyon, our energy levels are low.

Oh, this looks dodgy.

Don't worry [indistinct].

Georgie: Uh, passing my boat.

Steve: Give it a little shove.

Georgie: Yeah.

Steve: I got it.

Georgie: Thank you.

OK. Where am I gonna go?

Steve: Go, Georgie!

Georgie: I wanna go now.

Ohh!

No.

Man: Whoa!

Straight away, upside down.

♪ Aah!

Steve, voice-over: The relentless whitewater is taking its toll, and we're all making silly mistakes.

Paddle, paddle, paddle, paddle, paddle!

Move, move, move, move, move!

Aah!

Steve, voice-over: We pull in to scout the next section.

But stepping out, I'm slammed by a wave.

Aah!

♪ Uhh!

♪ Can you get my water [indistinct] paddle under the boat?

Uhh.

♪ Steve: That's it.

Good, Georgie, good, Georgie.

Whoo!

♪ Steve: Here's Georgie with this, she is.

You all right, George?

Yeah, good.

Just slightly stressed.

It was tough up there.

It was all a bit stressful situation, you know, where to get back in.

There's a lot going on.

♪ Steve, voice-over: Running on empty, we make it to our second camp.

♪ Steve: What do you think, team?

Does this look like a camp?

Man: Whoo!

[Indistinct chatter] ♪ Oh, guys!

Look at this!

I love it.

It's perfect.

Lots and lots of bear tracks are scattered around, but-- This might be someone else's favorite campsite, too.

[Laughs] Steve, voice-over: Sergey and his assistant Anton are not far behind.

They've been following an old lava flow right down to the riverbank.

♪ Sal: Hello!

How you doing?

Georgie: Hey, guys.

Man: [Indistinct].

♪ Steve, voice-over: With rain on the way, it's a race to get our tents up and the kettle on.

Milk?

Yes, please.

♪ Thank you very much.

No worries.

Steve, voice-over: For Georgie, a cup of tea doesn't quite cut it.

You've always gotta bring something to the river that makes you happy 'cause if it's gonna be a bad day, it's very good to have something nice at the end of it.

Ha ha ha!

So, there's my Croc filled with condensed milk.

I won't go without that.

Ha ha ha ha ha!

Steve: We had a pretty full-on day.

We certainly spent more time carrying our boats than we did paddling them.

Yeah.

I'm gonna feel it tomorrow.

I'm gonna wake up in the morning battered and bruised with every single muscle in my body screaming out.

♪ Steve, voice-over: What we all need is a good night's sleep.

♪ [Thunder] [Rain falling on tent] It's about 2:00 in the morning and it's raining hard for 3 or 4 hours now and there's no sign of letup.

The river will certainly react to this much rain.

It'll come up.

It will get heavier.

I just hope that this doesn't continue much longer.

[Beep] Steve, voice-over: By morning, the rain has stopped... but the river is raging.

We want to see how the downpour has affected the first section of rapids.

Oh.

Yuck.

Oh, that's not good.

Sal: There's a crazy amount going on.

Steve: I mean, you look at all of these big piles of logs.

One of those submerged that you don't see and you go under it and you will die.

There is no way you're getting out of it.

Sal: What we can see from here is that it just keeps going and going.

It doesn't actually let up.

There's a lot of very jagged fresh rock just under the surface, so, it can catch your edge and flip you over, and it's so shallow and sharp rock that you really wouldn't want to be upside down.

Steve, voice-over: This section of rapids is an ancient lava flow.

If we make a mistake here, we'll be dodging jagged volcanic rocks.

There is no room for error.

♪ We make a team decision to paddle the first 500 meters and then carry our kayaks around the logjam.

♪ ♪ I psych myself up with a practice roll... but I'm close to the edge.

♪ ♪ ♪ ♪ Man: There we are.

Paddle, paddle, paddle!

♪ Steve: That was a panic roll.

Get me the hell out of here.

Ha ha!

♪ Steve, voice-over: When we regroup on the riverbank, Tom, James, and Sal take a closer look at the next rapid.

Yeah, well, we're just in that channel, after the island.

Yeah.

Steve, voice-over: They're confident they can make it through the logjam.

...go into it, down on that... Steve, voice-over: Georgie and I are not so sure.

Georgie: Change of plans.

Ha ha ha ha!

Sticking to my guns.

I didn't like the look of it the first time and I still don't like the look of it now.

Aah!

Steve: You come with me, Georgie.

Georgie: Yeah.

♪ Steve, voice-over: It's a tough call, but we decide to split the team.

Tom: The plan is for us to kayak down this rapid, find a good place for the other guys to get back in as soon as we can, because we are short on time and we got a lot of distance to cover.

Steve: Hey, bear.

Hey, bear.

♪ ♪ Uhh.

It's horrible.

Pretty bad, isn't it?

Yeah.

Hot, sweaty.

It's gonna be a tough one.

This feels worse than yesterday.

♪ Steve, voice-over: Tom, James, and Sal steer clear of the logs... ♪ but they're being thrashed by the volume of the water.

♪ ♪ ♪ [Walkie-talkie beeps] Steve: Tom, Tom, go ahead.

[Static, beep] Where are you guys at?

[Static] Tom: We're on-- we're stationed just round the corner... Steve: Do you see them, George?

Tom: however.

I can't see them, I can't see an eddy, so, they must be further down.

Steve: Oh, look, look, look.

Bears.

♪ The mother and two cubs, running along the water's edge.

Unfortunately, it's me who's holding the camera.

♪ What an incredible sight.

♪ And the thought that you could stumble round any one of these corners and into that is pretty full-on.

♪ But the fact that they're there means that I think they're about to thunder right into our other guys.

[Beep] Tom, Tom, this is Steve.

Tom: Go ahead.

[Beep] Yeah, we still haven't located you.

Did you see the bear and the two cubs?

Tom's coming upstream.

We're up again.

Ha ha ha!

It seems like we made a good decision, but now we're gonna go down to where it's level because to get through these bushes is way too tough.

♪ Steve, voice-over: We reunite as a team, but we've lost valuable time.

♪ We've only made it 800 meters from last night's camp.

Today's target is 5 times that distance further downstream.

From this point on, we face continuous whitewater.

♪ Our best strategy is to find eddies, areas of calm water at the edges where we can pull in and regroup.

♪ James: Guys, guys, guys, this way!

Steve, voice-over: But the strength and volume of the river picks me up... and sweeps me straight past the rest of the team.

♪ Georgie: Go right, Sal, go right!

Sal: Yes.

Steve, voice-over: I'm battling to find an eddy to escape the relentless pull.

Aah!

♪ Steve, voice-over: Sal overtakes on the far side and James is right behind her.

♪ Ahh.

James: Now let's go to the eddy where Sal is.

Follow me.

Steve: Ahh, come on!

James: To me, Steve, to me, to me!

Steve: Aah, no!

As I struggle to keep control... we reach a section of river full of jagged rocks.

♪ Aah!

♪ Steve: Oh, no, no.

♪ Ahh.

[Coughs] Steve, voice-over: The rock forces me straight down another rapid and away from Sal and James again.

♪ OK, relax.

OK. Hey!

No.

James: That's it.

Hold there, Steve.

Now, get over there.

Sal: Get in there.

Paddle, paddle, paddle!

Steve, voice-over: Every ounce of strength... No!

has been drained from my arms.

♪ But Sal's not giving up on me.

Sal: Hup-hup-hup, hup-hup-hup, paddle, paddle, paddle.

♪ [Indistinct], Steve.

Hup-hup, Pring, hup-hup!

James: Good work.

Sal: Keep hold of me.

Steve: That was intense.

James: That was big.

Don't [indistinct].

Let's get out.

Steve: Ohh.

James: Sal, grab Steve's boat.

Thank you.

[Steve exhales] Well, we made some good progress, at least.

[James and Sal chuckling] Oh, that was really scary.

Yeah.

Oh, I've got that buzz of adrenalin, you know, when you're just shaking like a leaf.

Sal: I'm just gonna go upstream and signal to the guys that we're OK. Steve: I've just gone down completely blind probably some of the hardest whitewater I've ever done.

Would you say fairly consistent class 4?

I think the last one is 5.

It's pretty big.

It's only thanks to these guys that I'm managed to get back in here at all.

Otherwise, I'd still be going.

You missed the eddy but then from there on, you did a real good job of fighting, keeping--making good decisions and basically going out in the first place.

You did really well.

Yoo!

Everyone OK?

All right?

Steve, voice-over: The team is back together.

Steve: All right.

What now?

Sal: It looks to me like the cleanest line is between the two boulders, pointing a bit right.

♪ Steve, voice-over: I've got to get straight back into the saddle.

♪ Yoo-oo!

Tom!

♪ Georgie: We made it.

Sergey: Maiden journey.

Sal: Aah!

Sergey: [Indistinct].

Steve: Oh, Sergey.

I'm very pleased to see you.

Certain interesting.

Certainly interesting.

Go and have a nice lie down.

[Laughter] We have to take the kayaks on the top.

It's 100 meters.

Sal: Uhh.

Steve, voice-over: Up on the riverbank, Sergey has just what's needed to lift our spirits.

Georgie: Hey, where'd you get that from?

Sal: It's a brew.

[Laughter] Amazing.

[Laughs] Oh, is that not a brew?

No, this is a quadruple shot of vodka.

[Laughter] Come on, Sergey.

Where's the rest of it?

Sergey: In this one.

[Group cheering] Man: Now we're talking.

Sal: I bet Pring will.

[Laughs] Steve: Why not?

[Laughter] Steve: Oh, stop it.

[Group laughs] That's what I've been screaming out for all day.

[Person speaking Russian] Steve, voice-over: Teamwork is the key to all successful expeditions.

Man: Look at that perfectly chopped veg there.

Steve, voice-over: At the end of the day, the most valuable team members are the ones who can rustle up a hearty meal on a riverbank.

Tonight, Anton is treating us all to a Russian camping delicacy.

Anton: It's pea soup.

Russian name [speaking Russian].

[Man speaking Russian] [Anton speaking Russian] Sal: Has anyone got any favorite moments of the day?

I can tell you my least favorite.

[Laughter] Man: I can guess, actually.

I think my least favorite bit would be going backwards and upside down down a rapid and thinking I was going to die.

[Laughter] Actually, no, I'll tell you exactly what my favorite moment of the day was.

We'd just gone haring down some ridiculous, gnarly whitewater, and I pulled into the side and my eyes were on stalks and my heart was going like a drum, and Pring said, "Look at that," and the volcano had just peeped out through the clouds and was just hanging over us and it was so dramatic and you kind of go, "Wow.

"Yeah, we're in Kamchatka, "doing a first descent of a river.

This is epic!"

That was my favorite moment.

Steve, voice-over: The worst of the river is behind us.

Ahead lies bear central.

♪ So, Sergey and the rest of the team are joining us en route.

Breathe strong, vigorous, to carry on all this stuff.

More than 40 bags.

Steve: Look at that.

Oh, my goodness, that is amazing.

♪ Ha ha ha ha!

That is the greatest wildlife sight in Kamchatka.

The way it's moving around, the head swaying from side to side, it's very obviously looking for salmon breakfast.

He's huge.

Steve, voice-over: We're now well and truly in bear country.

♪ We have two days paddling to complete our first descent and reach the Pacific Ocean.

It's through prime bear habitat, perhaps the most untouched on the planet.

♪ It feels really, really good to have the whole team together, to have Sergey and Anton with us every step of the way.

You know, that's how it should be, the whole team working together on an exped.

Steve, voice-over: To help carry the filming kit, Tom takes charge of one of the rafts.

♪ [Men speaking Russian] ♪ Steve, voice-over: We launch into the tail end of the whitewater.

♪ Sergey is in his element.

I've been rafting more than 20 years.

I never rafted this river.

The first time.

This is a great--a great river for whitewater.

Steve: And we are making great time.

We are zipping down through these rapids.

It's lumpy, it's wavy, but it's fast.

Which is perfect for us.

Whoa.

This looks a bit hectic.

Aah.

Bear!

Bear!

Bear!

Bear!

Look!

Guys!

That was incredible.

Oh, that is crazy.

Steve: Oh, here they come.

Yoo!

How are you doing, Sergey?

Good!

I just saw the biggest bear of my whole life.

Even bigger than you.

Yeah?

He was huge!

And you're still alive.

What happened to the bear?

Ha ha ha ha ha!

I was quicker than he was!

Yeah.

♪ Oh, that was close.

[Speaking Russian] So, this now is our biggest obstacle, certainly for the rafts, is branches like this overhead.

They can so easily catch a rafter off guard and just pull him out of the boat.

So, it's our job as kayakers to signal to everyone behind us, let them know they're there.

♪ Steller's eagle, in the tree!

In the tree!

♪ The most impressive bird in the world.

Oh, it's just gone to the loo, which means it's about to take off.

Look at that!

Ohh, wow!

The female Steller's eagle is the largest eagle in the world, a wingspan of two meters and capable of flying away with prey the size of a small human child.

Not that they ever would, but they are so powerful.

And to me, it is the most striking, the most dynamic and dramatic of all birds.

I once traveled 1,000 miles to see a Steller's eagle.

And there's one just in front of us.

♪ The river now braids out into dozens of smaller channels, all brimming with salmon.

These are their spawning grounds.

♪ After a life at sea, they swim thousands of kilometers, returning to the exact spot they were born to lay their own eggs.

Sergey: This is where almost all species of Pacific salmon, king salmon, dark salmon, red salmon, 5 species.

Steve, voice-over: Exhausted after their migration, these salmon are easy pickings for a hungry bear.

Steve: Oh, my goodness.

That is a giant bear.

Absolutely spectacular.

This is a big male brown bear, often known as grizzlies.

Immense.

Thick fur, which is gonna help him out in the freezing Kamchatka winters.

Right now, he's wading around in the river, hunting for salmon.

How about that?

♪ Steve, voice-over: And it's not just the big males stocking up on this annual banquet.

♪ The mother with two older youngsters.

They could be two years old.

So, they're still with her.

This'll be around about the time that she's gonna be trying to drive them away, take on their own independence.

♪ This time of year, everything is focused on the river and on the salmon, because pretty soon, it's gonna be very, very cold here and covered in snow, and these bears will hibernate, and to do that, they have to have really significant reserves of fat, but essentially, it's all about fattening up for winter.

♪ Steve, voice-over: Everywhere we look, there are bears.

Most are so busy feasting on salmon they hardly give us a second look.

♪ Oh, that's another bear.

♪ Sergey: That was a big male.

[Indistinct].

♪ A lot of fish, a lot of bears.

♪ I've never seen anything like it.

It's like every single corner you paddle round, there's another massive big, brown shape lurking there, having its lunch out of the water.

I can't think of anywhere on the planet that has as high a density of big predators as right here.

I mean--oh.

There's one right there.

Look.

One right there.

How about that?

Ha ha ha ha!

And it's a testament to how much salmon there is here.

With these rivers stocked full of millions and millions of salmon, it's plenty for all these massive mouths.

♪ Steve, voice-over: In this pristine wilderness, Kamchatka's brown bears are thriving.

♪ They're top of the food chain in an untouched ecosystem where nature is perfectly in balance.

♪ It's a glimpse of what the world was like before humans.

♪ It's our final day paddling the immense Kronotsky River.

♪ Steve: Right.

Shall we?

Man: Let's do it.

Sal: Do it.

♪ Steve, voice-over: We're in no rush.

We're soaking up every last meter of the journey.

Here we go.

We got one down here.

Mike?

Steve, voice-over: This place is truly special.

Wow.

There's a bear in the river ahead of me plucking chunks of salmon.

♪ Oh.

My mind is blown.

♪ ♪ ♪ [Steve whispering] Oh, it's absolutely good.

Steve, voice-over: These bears have never learnt to fear humans.

Other bears around the world are not so lucky.

♪ ♪ What'd you think of that?

Incredible.

Pretty amazing.

[Both laugh] Tom: That was awesome.

That was so good.

♪ Steve, voice-over: After 40 kilometers of paddling, with the Kronotsky volcano towering over us all the way, we finally reach the Pacific delta.

[Birds squawking] ♪ Seals!

Seals!

Oop!

Ooh!

[Laughs] Steve: Super, super curious.

Really inquisitive.

Lovely!

Steve: It's like a welcoming party.

♪ Steve, voice-over: Sergey and the rafts pull into the beach, but we can't resist the call of the waves.

Look at that surf!

[Woman cheering] ♪ Steve: Oh, yeah, come on!

Taste the Pacific Ocean.

Ha ha ha!

Hoo-hoo-hoo-hoo!

♪ Whoo-hoo-hoo!

Oh, that is so beautiful.

♪ Oh, [indistinct]!

Whoo!

We made it.

Ha ha!

[Sal laughs] Steve: Sergey!

Anton!

Georgie: Anton.

Get close.

Sal: What am amazing way to finish our river.

Georgie: Thanks, Sergey.

You know, to think that now, in this day and age, that you can do something as massive as this and it be a complete first, it's-- it's unreal, isn't it?

I'm not even sure how to describe how epic that journey was.

I can't think of a more magical river with this good whitewater, the wildlife, and end up with some sweet waves.

You can't really ask for much more from a river.

It's been amazing.

♪ Steve: There is a million hectares of wilderness here in just this one reserve.

I mean, look at this.

Look at this.

♪ The air's filled with birds.

There are bears just wandering down the beach.

It is extraordinarily beautiful and now, ever more, it is a rare and unique place.

♪ We stand at such an important moment in time.

All this talk of extinction events, it can bring you crashing down.

We need things like this.

You know, what this expedition is to me is hope.

♪ If there remain places as perfect as this on the planet, then there is a reason to keep battling.

♪ Announcer: "Expedition with Steve Backshall" is available on Amazon Prime Video.

♪ ♪ ♪