Predators give us a dramatic health check on our planet's wild places.
They are the top of the food chain
and need an abundance of prey and vast territories for hunting.
But as the human population grows,
the conflict between people and wildlife is on the rise.
Over 75% of the world's top predators are now declining.
Humans have created this crisis,
but we also have the power to resolve it.
We meet the pioneers at the front line,
searching for bold solutions.
The question is whether we are prepared to allow room
for the natural world's greatest hunters.
The world's forests cover a third of its land surface,
and contain over 50% of our wildlife.
In the jungles of India, the top predator is the tiger.
Once on the point of extinction,
its numbers are now steadily rising here
for the first time in over 50 years.
India is also home to 1.2 billion people
and the fastest-growing economy on the planet.
So, how is the tiger making a comeback?
Tigers are the largest of all big cats.
They need a territory of up to 60 square miles
and must make a kill every week to survive.
He's so perfectly camouflaged.
A deer could just come close to him without knowing the tiger's there
and he'd just go for it.
Dr Ullas Karanth from the Wildlife Conservation Society
is the world's leading expert on tigers.
Watching a tiger hunt is a dream, it's just spectacular.
You realise what a perfectly-designed killing machine this animal is.
500 years ago, there were over 300,000 tigers in India.
But in the last century, their numbers fell to just 2,000,
due to a combination of poaching and the loss of half of their forest.
In the late 1970s,
tigers were almost on the verge of extinction in India.
But strong measures by the Indian government to create protected areas
and a strong law enforcement effort led to a major recovery
better than anything else the world has seen.
As a result, tigers have come back big time in many places.
There are now around 2,500 tigers in India
and their numbers are steadily rising.
The problem now is not so much a shortage of tigers,
it's a lack of space for them.
India's human population has doubled in the last 30 years.
With so many people living in national parks,
conflict is inevitable.
These enclaves make a living out of raising crops, raising livestock
and they're competing for space and food with tigers directly.
So, this forces a conflict on them
and eventually the tigers lose out and people lose out.
The government has come up with a radical solution -
paying villagers to move out of their homes, to make way for tigers.
Relocating local people out of the forest is a highly emotive issue.
India has been strongly criticised in the past
for carrying out forced mass evictions.
It is extremely controversial,
because in some places, it's been done badly,
where people who have moved out were forcibly moved out.
But in many other places, it's been done right.
Ullas' daughter Krithi also works for the Wildlife Conservation Society.
Her job is to manage their village relocations
and make sure they're done responsibly.
KRITHI SPEAKS INDIAN
Mani and his wife Jyothi
have volunteered to leave the forest in return for compensation.
TRANSLATION:
They feel very strong ties to this place,
even though they have a very difficult life here.
And constantly living in fear of elephants, leopards and tigers.
When you have little children, those challenges are even greater.
Mani and Jyothi are leaving their old way of life behind.
India is changing very rapidly and you have to sometimes make
really hard choices and sometimes that involves moving people.
And I'm very proud of the way we've done it right,
helping them through every step of the way.
But not everyone is happy about being moved out.
HE SPEAKS INDIAN
It's the fear of the outside and unknown that is keeping them here.
Once that fear is broken
and they know they are better off, everybody wants out.
Mani and Jyothi are the latest of 631 families
to leave Nagarhole National Park.
In total, almost 30,000 people across India have been relocated.
As humans move out of the forest, tigers move in.
A very strong proof that relocation works is to look at
some of the tiger reserves where it's been done well.
People have moved out, prey numbers have multiplied
and in many cases, the tiger numbers have doubled or tripled.
There are many, many such cases in India.
Mani and Jyothi are coming to live in a newly-built relocation centre.
Here, they will have to find jobs and fend for themselves.
Each adult receives the equivalent of £10,000 -
a huge sum in India.
This is paid part cash and part in the form of a new house
and three acres of land.
TRANSLATION:
There is a widespread view that forest-dwelling people
should live in remote locations,
cut-off from all signs of civilisation,
eating fruits and nuts, and that's far removed from reality.
What these people want is good education,
modern amenities and health.
And all of that is not available in the remote jungle.
People want to live in cities
and you're going to see this huge transition,
where India is going from 70% of the country being rural
to 50% of the country being urban in the next 20 years
and this is going to open up land.
And once you move people out, the vegetation comes back,
the prey numbers rebound and then tiger numbers come back.
So, ecological recovery takes time,
but I think nature knows how to heal itself.
Relocation may be an extreme solution,
but India's tigers are proof that given enough space,
predators can bounce back.
The greatest tropical forest on Earth is the Amazon.
It covers almost half of South America
and is home to more species than anywhere else on the planet.
In the jungles of Venezuela, the canopy's deadliest hunter -
the harpy eagle.
This is the most powerful bird of prey in the world.
It has a two-metre wing-span,
and it hunts silently, on the lookout for monkeys and sloths.
HARPY EAGLE SCREECHES
The harpy eagle's territory stretches over 30 square miles.
At the heart of it, the nest, with a very hungry chick.
At two months old, the chick is vulnerable
and is fiercely guarded by her mother.
Down below on the forest floor,
others are also keeping a close watch.
Dr Alexander Blanco monitors 20 different pairs of harpy eagles,
trying to police this area of forest
and keep the nest sites safe from human encroachment.
Throughout the harpy eagle's range, across Central and South America,
an area of forest the size of Switzerland
is being cut down every year.
CHAINSAWS BUZZ
Alexander is studying the impacts of this loss on the harpy eagle -
and to do that, he must first get himself
35 metres up to the nest in the canopy.
HARPY EAGLE CHIRPS
When the chick reaches six months old, before she fledges,
Alexander must climb up and bring her down.
He'll then fit a small radio transmitter on the chick,
so he can keep track of her after she's left the nest.
The mother eagle could attack,
so Alexander is wearing a stab proof vest.
It's dangerous work,
but it's driven by a lifelong passion for the harpy eagle.
As soon as he reaches the nest,
Alexander must secure the harpy eagle's deadliest weapons -
its talons.
HARPY EAGLE SCREECHES
Today, the female is keeping her distance,
but Alexander has been attacked several times.
OK...
But as Alexander starts his descent,
he realises there's a problem with his ropes.
DULL THUD ALEXANDER SCREAMS
AMBULANCE SIREN
Amazingly, both Alexander and the eagle survive the fall.
But Alexander breaks both his wrist and his leg.
Alexander's assistant Don Blas
brings the young eagle back to camp, to keep an eye on her.
Don Blas attaches the radio as planned.
Very little is known about these eagles,
so this transmitter will help the scientists understand
how they survive in a disappearing forest.
Finally, the team return the young eagle to its nest,
under the watchful eye of her anxious parents.
The adult eagles waste no time bringing in more prey...
..and life at the nest returns to normal.
The harpy eagle is now 18 months old.
Alexander is returning to study her progress
for the first time since his fall.
The transmitter on the eagle sends out a radio signal
and the scientists can now track her through the forest
as she learns to hunt.
TRACKING APPARATUS BEEPS
She can now recognise her prey,
but she's doesn't expect it to fight back.
But Alexander's studies show the monkeys and sloths
that form the eagle's main prey
are disappearing as the forest is cleared.
In the face of this crisis,
the harpy eagle has proved to be remarkably resourceful.
The eagles are starting to hunt ground-dwelling prey
in more broken areas.
There are now less than 50,000 harpy eagles left.
At the current rate of deforestation,
their numbers will drop by a third in the next 50 years.
The only hope is that Alexander's data
will persuade governments to protect their habitat,
even if he has to risk his life in the process.
Nearly half of the world's land surface
is covered by grasslands and deserts
and none are richer than the plains of Africa.
This vast savanna is home
to some of the most celebrated predators on the planet.
And the most celebrated of them all is the lion.
The Ngorongoro crater in Tanzania
has the highest density of lions on Earth.
There are four prides of lions here
and they're engaged in a constant war with their human neighbours,
the Maasai people.
The Maasai rely on their cattle for survival.
When the lions attack their livestock,
the Maasai retaliate by killing them.
This is an ancient conflict between warrior and predator
that's been played out for millennia.
The human population here has nearly tripled in the last 20 years
and the conflict has now reached crisis point.
Craig Packer is the world's top lion expert.
He and assistant Ingela Jansson
are trying to stop the Maasai from killing lions
and allow them to breed in peace.
Those animals have to run the gauntlet of Maasai with spears.
And so, with that kind of armed guard all the way round the crater,
it's very difficult for the males to be able to come into the crater
from somewhere else to rejuvenate this population.
Time is running out for the lions of Ngorongoro.
Craig has roughly 100 of them
and the Maasai are killing an average of ten a year.
The one with the scar, MG103 -
she had cubs in May and two of hers were lost
and I didn't even see what sex they were.
Whenever one of our study lions is speared,
it's like right, that's just one more nail in the coffin.
It's like one more example of why something must be done
to address this problem.
The only way to solve the conflict here
is by brokering peace between these two ancient enemies.
Ingela and Craig have employed a team of Maasai scouts
from within the community.
Their job is to document lion attacks
and try and stop people from retaliating.
So, I'm asking them "Do you like lions?"
And yeah, there was some murmuring "yes" but then she said,
"No, I don't like lions", because a lion attacked her son last year.
SHE SPEAKS MAASAI DIALECT
Oh, he's like 22 years old.
He went then to defend their livestock
and then he got into a close fight with a lion.
After four years of Ingela's incredible dedication
to slowly, gradually build trust with people,
people are very much are more likely to tell her what's happened.
They might even have speared a lion in retaliation.
So, she can get a better picture of what really happens here.
And therefore, how best to improve circumstances.
TRANSLATION:
Craig, Ingela and their scouts have their work cut out.
The war between people and lions has been waged here
for over two million years.
And there is one deadly tradition
that's still widely practised today -
the ritual killing of lions.
The team are travelling to a remote settlement
on the edge of the Serengeti.
MAASAI SING
This is the front line in the conflict with lions.
We've come out here today to attend a Maasai wedding
in an area that's had a lot of ritual lion killing
over the last decade.
One of the things that Ingela has learnt in her research
is that these hunting parties often assemble at an event like this.
So, as you can see,
everybody's getting worked up and that level of excitement...
It's like they've got all this energy and all that testosterone ready to go
and one of the things they really get excited about doing is going to hunt a lion.
Ingela is hoping that the presence of her scouts
may be enough to deter the warriors from hunting lions.
They know these guys, they're friends, they're relatives
and everyone knows here that they work for Lion Conservation,
so they kind of know that they can't go hunting if that person is present.
Ingela's head scout, Roimen, comes from this area.
He killed two lions by himself in ritual hunts when he was younger,
and has the respect of his fellow warriors.
ROIMEN SPEAKS MAASAI DIALECT
Today, no-one is going hunting and the lions in this area are safe.
But it could take decades to solve the conflict,
so Craig is proposing a highly controversial solution -
putting up fences to keep people and predators apart.
Our romantic visions of Africa's unspoilt wilderness -
that's already out of date.
The human population now is already one billion people.
It's expected to quadruple by the end of this century.
So, it's time to consider erecting fences between people and wildlife.
It's time to rethink the basic need
for the safety of the people around these parks
and the safety of the animals themselves.
Craig is calling for fortress conservation -
protecting vast areas with hundreds of miles of electric fencing.
In South Africa,
all the wildlife parks have already been completely fenced in.
There are now 1,000 highly protected game reserves here
and the number of top carnivores is steadily rising.
But for wide-ranging predators like cheetah,
being fenced in poses a deadly problem.
Cheetahs need vast territories to survive.
The world's fastest land animal is mainly solitary
and must roam long distances to find a mate.
But when they're trapped in behind fences with their own families,
in-breeding becomes the biggest threat to their survival.
The only way to prevent this is by playing Cupid with cheetahs.
Vincent Van Der Merwe from the Endangered Wildlife Trust
runs what could be described as a cheetah dating agency.
These population are small
and inbreeding is a terrible thing, in the long run.
So, it's not a natural thing, you know?
We'd prefer natural dispersal,
natural migration between the populations,
but South Africa is a highly-developed country
compared to the rest of Africa.
And you know, we have to move them artificially.
Vincent has come to Dinokeng Game Reserve to remove two males.
They're 18 months old
and would normally have left their mother by now.
So, these two males are related to the two females
and they're reaching sexual maturity now,
so there is the possibility that inbreeding will take place.
So, it's important that we remove these two males to prevent inbreeding.
Before they can be moved,
the cheetah must be immobilised by wildlife vet Shaun Beverley.
Let's just have a look and see.
I just want to check what these two do.
Just reverse.
Stop here.
These animals are very sensitive to drugs
and there's a high risk of overdose or injury.
OK, I'm going to take it.
Just watch the female - she's not happy at all about the vehicle.
She's quite intent in protecting her... The young male.
CHEETAH HISSES
With an eye out for the angry mother,
Shaun carefully removes the first young male.
Ready. We're just going to pop him in here.
By collecting DNA samples, Vincent creates a profile for each cheetah
and matches them up with unrelated females on other fenced reserves.
OK, got some blood vials over there.
A single population on a small fenced reserve like this
is not viable in the long term.
But 53 small populations on 53 reserves
are viable in the long term, if managed as a single population.
So, we continuously have to move these cheetah
between the 53 small fenced reserves
to ensure that they remain genetically viable.
Just support his neck here.
You can put it in as deep as you can
and just grab him from the outside and drag him through.
Just give him an antidote.
Far more comfortable, once they're awake.
CHEETAH HISSES
OK, let's go.
ENGINE STARTS
Vincent has now moved 98 cheetah.
But alarmingly, one in five of them have died in the process.
It's a terrible price to pay for conservation.
A small box, it's a very, very confined space for a cheetah.
We don't like to keep them there too long.
Unfortunately, some of the reserves are really far from each other
and we have to move them over a day or two.
So, we really fear for them,
and we lose a lot of cheetah because of chronic stress.
CHEETAH HISSES
The two brothers are travelling 100 miles to their new home,
Sable Ranch, where they will stay for the rest of their lives.
Plenty of cheetah food over here.
These two young cheetah have survived their journey unscathed.
They are doing 100%, just a case of opening up now.
CHEETAH HISSES
Vincent will soon bring in a female, so they can start a family.
When their offspring have reached adulthood,
they'll need to be moved to another reserve.
It's never-ending work.
There are now less than 10,000 cheetahs left.
South Africa is the only country where the population is growing,
thanks to human intervention.
But at what cost?
Will all of Africa's wildlife end up living on fenced private reserves?
I really think that this is going to be the future of conservation,
because we're not going to find wide open spaces in Africa any more.
There's just too many people, too much development.
But we will find small fragments of natural habitat
where we can reintroduce cheetah.
So this is really a way to increase the range of cheetah,
to beef up their numbers,
because in the rest of Africa, their numbers are going down.
There is at least one place left in Africa
where you can still find wide open spaces.
Zambia.
With over 100,000 square miles of untamed wilderness,
Zambia is simply too large to fence in.
One hunter needs this vast landscape more than any other
and it's the most endangered of all the predators on the plains.
The African wild dog.
Wild dogs are highly social animals.
Before hunting, they carry out a greeting ritual,
reinforcing bonds within the pack.
They also care for their old and injured,
making sure no dog goes hungry or gets left behind.
But these greetings are becoming a rarity.
Wild dogs have lost over 90% of their former range
and there are now just 6,000 remaining in the whole of Africa.
Mike Bravo, go ahead.
Yeah, we have the hot springs pack just upstream.
Copy that, going there right now.
It's five o'clock in the morning
and a team from the Zambian Carnivore Programme
are tracking a pack of wild dogs.
Their study animals are getting caught
in the crossfire of a war with illegal poaching
and Thandive and Henry are trying to keep watch over them.
It's a huge area and to look for animals like that
is like looking for a needle in a haystack
and worse still, these dogs are moving at really high speeds.
They're heading out hunting, huh?
They're joined on their search by air support.
Team leader Dr Matt Becker is spotting from above,
trying to work out which direction the dogs are heading.
Tango Mike, Tango Mike, Mike, Bravo.
Mike Bravo, go ahead.
Yeah, we have the hot springs pack -
got a visual, all 15 of them, just upstream from the Kalousie.
Copy that, we'll head there right now and try to keep up as best as we can.
OK, sounds good.
Wild dog territories stretch over 600 square miles.
They're constantly on the move,
so the scientists track them using radio collars.
If you don't follow them on the ground for a couple of days,
you often have no idea where they may be.
So the quickest, easiest thing to do is get up in the air
and pick up the signal from a long ways away,
and then, we'll radio those locations to our ground teams,
who will come in with their Land Rovers
and follow the dogs on the ground
and collect all sorts of critical information on them.
Mike Bravo, I copy that.
Do you have the location right now?
Yeah, I've got them. 11 o'clock, moving in now.
Oh, that's great.
The team observe the pack hunting almost every day.
Once they've selected their target, it's all about teamwork.
When they actually encounter wildebeest or other prey,
you'll see them reacting to where the other dogs are running as well.
They are very aware of what's going on
and what their other pack members are doing.
You know, they take down wildebeest
that one dog can't possibly do by itself,
so through working together and helping each other out,
they're able to take down big animals like that.
No matter how many times I see a wild dog hunt, it's always amazing.
The grace and speed of the dogs in a hunt
is something that you can't get with any other species.
There's nothing like wild dogs
and if we lose them, there will never be anything like them again.
The greatest threat to wild dogs comes from humans.
The dogs are getting caught in snares intended for other animals.
Zambia's growing population is creating a huge
and increasing demand for commercial bushmeat,
with poachers targeting species like gazelles.
But snares are indiscriminate
and thousands of other animals are caught by accident.
With the dogs in constant danger,
the team keeps an eye on them, in case they get caught in snares.
To follow the dogs, they need to collar only one animal,
as they normally stick together as a pack.
WILD DOG YELPS
Once the dog is safely down, the team can slowly move in.
A lot of them are getting snared.
And so, these radio collars enable us to get an animal,
find it and de-snare it.
So, this collar may save this dog's life,
it may save its brothers and sisters and other pack members.
So, once the pack member is down, the other dogs will stay in the area.
As you can see, some in the background -
so that makes it easier for the immobilised dog to join the group
after the drugs wear off.
When he comes round, the young male is unsteady on his feet,
but he soon catches up with the rest of the pack.
I think the best sight of the whole darting
is when the dog gets up and rejoins the pack.
It doesn't get any better than that.
The team are searching for a pair of females that they're worried about.
It's not unusual for females to leave the pack
to look for new males,
but these two sisters have run into trouble.
A few weeks ago, we de-snared one of the females -
she had a snare around her waist
and was actually one of the worst we've ever seen.
If you look very closely, you can also see just where the wire was.
Her sister's also got an injured back leg.
We can't see any open wounds at the moment,
but she's clearly not putting any weight on it at all.
And that does not bode well for them,
when it comes to hunting, looking for food.
Looks like they have not eaten for a while, now.
They look very thin.
I don't think they have a good chance of survival.
We will keep monitoring them and see how it goes.
It's going to be difficult. We might just end up picking up
two empty collars in the next few weeks.
Sadly, the snared female doesn't make it
and is found dead a month later,
but her sister manages to join another pack.
Matt's team works closely with anti-poaching patrols
from the South Luangwa Conservation Society
and the Zambian Wildlife Authority,
looking for snares and searching vehicles for bushmeat and guns.
But as always, the greatest weapon in the war against poaching
is the next generation.
HENRY SPEAKS AFRICAN DIALECT
This is conservation club.
Every week, Thandi and Henry take children on safari,
so they can appreciate wildlife and the opportunities it brings.
How many people have seen wild dogs before?
They hunt in packs of course,
and they prefer to chase the animal down.
Probably the most important aspect of our work
is ensuring that the people that are most responsible for conservation
of wild dogs and wild life in general are the Zambians themselves.
Henry and Thandi are fantastic and are continuing
to help kids get engaged in wildlife conservation.
For those of you that have never seen a snare before,
this is what it looks like.
The mechanism is so that it should tighten
as the animal struggles to get away.
The best thing that can come out of this is a generation of people
that are interested in wildlife.
Regardless of what field they join later on -
they could be teachers, or bankers, or whatever -
but just environmentally-minded people.
The animals are important, because they are the sources of income
that can develop our Zambia - our nation.
When I grow up, I just want to teach people about wildlife.
Just like Mr Henry do.
Oceans cover over 70% of the planet.
This immense blue wilderness
is home to the largest predator that's ever lived...
..the blue whale -
up to 30 metres long and weighing 200 tonnes.
Since commercial whaling was banned 30 years ago,
off the coast of California,
its numbers have almost fully recovered.
But they face a new problem.
Here, blue whales are feeding on krill,
in one of the world's busiest shipping lanes.
Container ships plough through these waters 24 hours a day,
heading in and out of Los Angeles.
When the bow strikes a whale, it's usually fatal.
Some scientists have suggested that this could be one reason
why the blue whale population here is not increasing.
But proving it requires very challenging research.
So, we'll go through the area where we've had the sightings
and it looks like both those whales moved last night
to the shipping lanes, right in that zone...
On the MS Shearwater in LA harbour,
a team of marine biologists are heading out to hunt for blue whales.
Their mission is to investigate the impacts of ship strike.
I think we'll have a chance at this angle -
it looks like he's back into
a little bit more of a travelling mode.
John Calambokidis from Cascadia Research
is the world's top expert on blue whales
and has been studying them for 29 years.
I first became aware of the ship strike issue in 2007,
when we had at least four blue whales that were struck
and killed by ships just in Southern California in a few months' period.
The port of Los Angeles Long Beach
is the largest shipping complex in the United States.
Container traffic here has increased ten-fold in the last 30 years.
This spot right here probably has
some of the densest concentration of ships
that will funnel through here, coming into Los Angeles Long Beach.
This also, right here, is a canyon
that has quite a bit of krill for blue whales to feed on.
And we've often got concentrations of blue whales
right in this same area.
John is tagging a number of whales
to see how they respond to the ships.
Right now, we have a whale that's in the shipping lane,
so we're going to try to take this opportunity
to put a tag on this whale,
monitor both what it's doing and get the reaction of the whale.
Deploying a suction cup tag requires precision timing.
This first critical point, till you figure out what a whale's doing,
it's very easy to lose it.
Right now, there's a little bit of pressure.
He may come up again here.
Yep, here he comes.
All right! Let's go.
Coming up.
OK, nice job there.
So, that's attached with a suction cup.
We hope it will stay on
for something of the order of a few hours.
These modern day whalers with hi-tech harpoons
are hunting for new information about the whales' behaviour
and why they don't simply swim out of harm's way.
Blue whales don't seem to respond very strongly to the ship presence.
You think about a long ship,
the engine of that ship that's generating the noise
and the propeller are all the way at the far end.
What might be of danger to the blue whale
might be 300 metres in front of that.
The tags reveal how much time the whales spend in the shipping lanes,
especially at night.
The first thing that's rather surprising
is that the whale crosses the shipping lanes twice.
And we see that the blue whales are spending
about twice as much of their time at night near the surface,
where they will be vulnerable to being struck by a ship,
compared to the day time.
John is now working with the authorities
to try to divert the shipping lanes and slow the vessels down.
All sides are keen to find a solution
and allow the whales to feed in peace.
The polar regions are the least-inhabited
and the most remote wildernesses on Earth.
Here in the Arctic, the top predator is the polar bear.
Over almost half a million years, these bears have adapted to
the Arctic's dramatic annual changes of season.
They're the only predators to hunt on sea ice
and they rely on it for almost all of their prey.
But due to changes in the global climate, the ice is getting thinner.
And their season for hunting is getting shorter.
To prove this is happening, you need hard evidence.
And there's one team of scientists
who've been collecting that evidence for the last 30 years.
What is that?
It might be a swan.
- Oh, just this side of the ridge? - Yeah.
In West Hudson Bay in Northern Canada,
Government biologists are carrying out
the world's longest study on polar bears.
Oh, there's a bear, right below me - holy smokes.
I think if I was going to do this guy, I'd try to get on his left
and just push up onto this ridge here.
If we get him on this ridge, I think we're laughing.
The scientists are like health visitors for bears,
checking the pulse of the local population.
For Dr Evan Richardson, summer is the perfect time to call.
As the bears are resting on land right now,
living off their stored fat reserves, waiting for the sea ice
to come back in the fall, in November and December,
it really gives us a good opportunity
to come and study this particular population of bears.
The bears need to be immobilised
before the biologists can get to work.
I'll just keep pushing him in the direction he's headed now, OK?
Dr Nick Lunn's team has darted over 5,000 bears
since the project first started.
That bear's going into the water.
It's a place they consider safe, they head out to sea.
And we don't want to be darting him in the water,
so we need to move him back out where we can get a safe shot
and have him go down on the land.
Though it's stressful for the individuals in the short-term,
this research could help save the entire species in the long-term.
Once the dart is in,
the crew wait at a safe distance until the bear is down.
They must be extremely cautious when leaving the helicopter.
Working around polar bear country, one always has to be vigilant
and aware that there are other bears around -
they're curious, they're going to come in.
We have firearms, as a protective measure, just in case of an incident.
Let's see if we can reposition him - which might be easier said than done.
The team have to work fast.
Once the anaesthetic wears off,
this bear will quickly become very dangerous.
This bear was first caught back in 2003
and he's got about another ten capture histories.
We collect hair samples, we'll take fat samples,
we'll take a few standard measurements.
Head length - 343.
So now, we're going to get a straight line body length of this bear.
233.
His canines are one. Tooth wear is one.
By updating their health records each year,
the team can keep an eye on this bear's condition.
The number is 016.
Typically, male bears would be
10% larger than this particular individual,
so the bears are actually shorter,
smaller than they used to be in the 1980s and 1990s.
We believe it's probably related to nutritional stress
and the population and reduced access to food.
The bears are going hungry
because the winters here have become warmer and shorter
and the summers longer and hotter.
The bears need to see ice as a platform to hunt their prey,
to travel, they mate out on the sea ice,
but we see sea ice breaking up
around two and a half to three weeks earlier
and forming around two and a half to three weeks later,
so the bears have less time to feed.
They're thinner, they don't have the same amount of fat on their bodies.
We're seeing fewer cubs being produced, declines in cubs' survival,
bears coming ashore in poor condition,
weighing a lot less now than they did 30 years ago.
The scientists can now prove that these bears are, on average,
20% smaller than when their study first started.
If the loss of ice continues,
the polar bear will gradually become extinct.
Climate change is happening fairly rapidly,
so even though these bears are really good at fasting
and living off their body reserves and going long periods without food,
what we're seeing is, we're starting to push these bears
to their physiological limits,
and as they're pushed to the limits of their body reserves,
obviously, that has implications for their survival.
More than any other predator,
the polar bear has evolved to cope
with dramatic changes in the Arctic seasons.
But with the current pace of climate change,
the bears simply cannot adapt fast enough.
If polar bears are to survive,
we will all have to play our part.
DR ULLAS KARANTH: If people do smart things,
like different ways of producing energy,
I think we will have room for large predators
as well as people living really well.
- JOHN CALAMBOKIDIS: - If humans are going to survive on this Earth
and do so in harmony with other species,
we're going to have to find a more sustainable way to live than we do,
and a lot of that is going to have to involve
lower levels of consumption.
We have to accept the fact that
we can't just blindly go on the trajectory we're currently on
and expect things to work out well.
We've got to make changes.
CRAIG PACKER: We need to start thinking about the ways
the whole world can contribute.
These precious animals belong to all of us.
These are a world resource
and the world as a whole should guard these animals against poachers,
habitat loss and protect them into the future.
If we can't save the planet's most charismatic predators,
what hope is there for the rest of the natural world?
Wildlife has the power to recover
and people have the power to change.
What happens next depends on us.
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