Original subtitles

Welcome back to the Bahamas, a

paradise for sharks big and small. I'll

I'll be following their epic migrations

migrations and seen what the future holds

holds for the next generation. And I am

am flying over Mexico's Sea of Cortez

Cortez looking for whales, dolphins, seals

seals and sharks, live! And, on the other

other side of the world, as the sun is

is rising, I'm taking to the water, discovering

discovering how all the animals here contribute

contribute to the health of the Great

Great Barrier Reef. Join us for all the

the action and more on Blue Planet Live.

Hello and welcome back to Blue

Planet too, for one whole week we have

have our teams in strategically selected

selected locations across the globe. Two

Two years on from Blue Planet two, this

this is an opportunity to take a snapshot

snapshot from a moment in time. One week

week in our ocean's 3.8 billion year history

history to find out how they are faring

faring and revel in their glory. Tonight

Tonight we will follow marine wildlife,

wildlife, embarking on vast migrations,

migrations, crossing seas and oceans,

oceans, finding out how those marine habitats

habitats are all interconnected. And events

events in one place can have impacts thousands

thousands miles away. The

The world's oceans. The Atlantic. Pacific.

Pacific. Indian. Arctic. And Antarctic.

Antarctic. All joined by powerful currents.

currents. Together, they form one, global

global ocean, a vast, interconnected body

body of water, shifting heat... Nutrients

Nutrients and life around the planet.

planet. Shaping our climate... Defining

Defining our way of life, like a ripple

ripple effect, what happens in one corner

corner impacts another. With warming waters,

waters, plastic pollution, overfishing...

overfishing... And, increasingly powerful

powerful storms, understanding our Blue

Blue Planet as one ocean is key to how

how we protect it.

how we protect it. So, our teams are live

live broadcasting now from three different

different time zones. So, where am I?

I? Well, I'm in the Bahamas, specifically

specifically in Bimini, in the Atlantic

Atlantic Ocean. We are 4000 miles away

away from the UK and this place is a globally

globally important shark sanctuary. Liz,

Liz, on the other hand, is on the other

other side of the world. She is, before

before her breakfast coffee, getting up

up before the door 9000 miles away in

in Australia. Thank you very much. Tonight

Tonight I'm finding out how what happens

happens where you are can have a direct

direct impact on where I am here on the

the Great Barrier Reef. Meanwhile, Chris

Chris is 7000 miles away from us in Mexico,

Mexico, taking to the skies. Yes, hello,

hello, and welcome to the Sea of Cortez.

Cortez. I've widened my field of view

view today by jumping on board our helicopter

helicopter to take part in an aerial survey.

survey. Our mission is to bring you some

some ocean giants. Yesterday we promised

promised blue whale and I'm ashamed to

to say we failed you butter fingers are

are crossed today because we are confident

confident we are going to find some whales,

whales, and if not those, then some other

other large marine animals. It'll be fantastic,

fantastic, Steve! Over to you! Thank

fantastic, Steve! Over to you! Thank you

you very much, Chris. We will scour the

the skies, we will find them on the beaches,

beaches, we will even wade around in tidal

tidal mud to find marine animals and give

give you a health check of our oceans

oceans right now. Blue Planet II showed

showed how animals and particularly sharks

sharks undertake migrations, crossing

crossing oceans, and an awful lot of them

them are turning up right here in the

the Bahamas. We have at least 78 species

species of sharks and rays using these

these waters as a sanctuary, the fact

fact it is protected has an enormous impact

impact for their lives. But why are they

they coming here to the be Hamas? Well,

Well, a part of the puzzle and part of

of the answer lies with one of their close

close cousins, the stingrays.

I'm being overwhelmed by what looks

like a flotilla of flying carpets. These

These are southern stingrays, an animal

animal closely related to the shark. The

The eyes are on the top of the body looking

looking upwards. And the mouth is on the

the underside. Let's see if I can get

get this one in close to my underwater

underwater camera so you can see that

that mouth. There it is! They have the

the sting that gives them their name,

name, and that is down here at the base

base of the tale. If you look it up really

really close, it has a lacerating edge

edge to it, coated in venom. That stinger

stinger is its way of defending itself.

itself. Hammerhead sharks have been found

found with dozens of those stingers embedded

embedded into their mouths. I've seen

seen one or two males around but, almost

almost all of these are big females. Why

Why are they here, right now, in these

these shallows? Well, there is only one

one way to find out.

Yes, we will try to answer that

question right now with the help from

from some of my friends from Bimini Shark

Shark Lab, the most fantastically named

named Institute of learning in the entire

entire world. You've been studying the

the sharks and rays for a long time, Matt

Matt Smukall. This is a female, what's

what's going on? If you look at her here,

here, she looks very descended but you

you never want to assume she is pregnant

pregnant so we are going to go ahead an

an ultrasound her to see if we can look

look at her pups to try to understand

understand how big they are. If

look at her pups to try to understand how big they are. If

understand how big they are. If you want

want to put your hand here,

understand how big they are. If you want to put your hand here,

want to put your hand here, you can feel

feel the pup moving around. Are you serious?

serious? Yes, it's kicking. Do you ever

ever wake up and go, I have the weirdest

weirdest job in the world? Yes, but also

also the greatest. Look at the ultrasound,

ultrasound, you can see the mouth of the

the pup moving within the uterus. These

These pups are near term. I can see the

the little, small dot no actually, I saw

saw it! That is incredible! We can tell

tell based on the bars that the pups are

are near term so she is close to popping

popping any day now. Now that we've confirmed

confirmed she's pregnant, we're going

going to let her go. I can actually feel

feel that movement, the movement of her

her pups, incredible! I never thought

thought I'd get the opportunity to do

do that, that is incredible. If you notice,

notice, she is missing her barb. We have

have a lot of stingrays and other sharks

sharks that come to this area for reproduction

reproduction to speed up gestation in

in the warm waters so they are coming

coming in and foraging on things like

like sting rays and turtles. Well, that

that was a very quick health check, she

she certainly looks stress-free, should

should we let her go? Let's let her go

go on her way. Fantastic, there she goes.

goes. Not this way! Anyway but this way!

way! Gliding off in between us both. Sensational!

Sensational! Now, Matt, why are these

these waters so important to stingrays

stingrays and sharks? The Bahamas are

are productive for a number of fish species

species are not only do you have great

great fish but you also have the stingrays,

stingrays, turtles, then the predatory

predatory sharks coming in at the top

top of the food chain with the warm waters.

waters. It is a great way to speed up

up gestation and metabolism. We will be

be learning lots more about that in the

the show. But, for now, let's head all

all the way across the world to Liz, who

who is on the water on the Great Barrier

Barrier Reef. Thank you very much, Steve,

Steve, we are just off the jetty on Heron

Heron Island, it's a beautiful morning,

morning, check out the magnificent backdrop.

backdrop. This week, we've been looking

looking at the activities of green sea

sea turtles and I've positioned myself

myself over what is known as a cleaning

cleaning station so let's go to our live

live underwater camera to take a look

look at what we've got, if we have got

got some green turtles. Take a look at

at that! Hello, turtle on our cameras!

cameras! What they do is they start to

to gather around these cleaning station

station scattered across the Great Barrier

Barrier Reef for a very important task

task indeed. They are going to try and

and solicit the help of these cleaner

cleaner fish, little cleaner fish that

that love to eat the algae and parasites

parasites of the skin and the shells of

of sea turtles. It is a mutually beneficial

beneficial relationship. This is an image

image from a couple of days ago on this

this cleaning station where the turtle

turtle stretches out her neck, saying

saying to the little fish, "Clean off

off the parasites, get your fill of algae,

algae, I'll feel better, my skin will

will be cleaner, and you will get a lovely

lovely meal". It's a beautiful place to

to be at this time of the morning. As

As we saw on Blue Planet II, turtles are

are great Ocean wonders spending about

about 90% of their lives in the ocean,

ocean, they hatch on the beaches, then

then they head out to sea and they only

only return to land to nest and lay their

their eggs. The distances that turtles

turtles travel can be simply staggering.

staggering. Now,

Now, hatchlings travel to greatest distance

distance of their entire lives for the

the most part at the mercy of the currents.

currents. Loggerhead turtles from this

this area of the divorce - make Great

Great Barrier Reef go past New Zealand,

Zealand, all the way across the Pacific

Pacific to Chile and Peru, a distance

distance of 8000 miles. Now, at about

about 16 years of age, the turtles will

will have made their way back across the

the Pacific towards the Great Barrier

Barrier Reef and at that age they are

are known do to make known as juveniles.

juveniles. They are not ready to breed

breed yet. They establish foraging grounds,

grounds, find where the best food is and

and that is where they will stick for

for about 13 years. Once they are mature

mature enough to breed, they head back

back towards the beaches, where they first

first were born, and near those areas,

areas, they will set up breeding locations

locations as well where they will nest.

nest. And during their adult lives, so

so around 30 years and upwards, they move

move back and forth between those two

two locations, distances as great as something

something like 1600 miles, even 2000 miles.

miles. The green sea turtles on Heron

Heron are known to travel up to Indonesia

Indonesia and the Coral Sea to feed, then

then they come back here to nest. As these

these turtles travel, they are transporting

transporting incredibly important nutrients

nutrients to all of the areas they travel

travel to. There is a live turtle there,

there, just beneath me! Oh, such a treat

treat to have them so close to us! And

And these guys travels so far throughout

throughout their lives, that all of the

the nutrients that deposit in the form

form of poo, basically, they are incredibly

incredibly important to the oceans. The

The parasites... Look at her! She is breathtaking!

breathtaking! But the parasites and the

the barnacles on their skin as well as

as the algae they get travels around the

the oceans as well, they are like hitchhikers

hitchhikers and sometimes they will drop

drop off on a completely different part

part of the ocean which adds to the biodiversity

biodiversity of the oceans and adds to

to the health of it. Honestly, the roles

roles of these green turtles around our

our oceans cannot be overestimated. Oh,

Oh, my gosh, she is breathtaking! She

She is right under us, getting ready for

for a bout of cleaning. The threats to

to our oceans are on the increase of it

it means that as these turtles migrate

migrate all around the planet they are

are exposed to more and more dangers.

dangers. So, I travelled to the Cairns

Cairns Turtle Rehabilitation Centre a

a few weeks ago to find out a little bit

bit more. This

This image of a turtle entangled in plastic

plastic from Blue Planet II was a shocking

shocking revelation for many but in the

the past few years public awareness and

and funding for the rescue and rehabilitation

rehabilitation of turtles has increased.

increased. Providing a lifeline for these

these endangered creatures.

these endangered creatures. This is Midori,

Midori, a rescued green sea turtle. She

She was found over two years ago with

with tumours and plastic blocking her

her digestive system. Following an extensive

extensive treatment plan by the total

total rehabilitation centre in Cairns,

Cairns, we have privileged access to see

see if Midori is fit enough to be released

released back into the wild. Thankfully,

Thankfully, she has now passed all the

the plastic in her system so Jenny Gilbert

Gilbert and her team are giving her a

a scan to reveal if she is finally free

free from tumours. So, Jenny, what are

are your thoughts, looking at the scan?

scan? I can't see any tumours and we haven't

haven't picked up any plastic. As she

she ready to go? She is healthy and ready

ready to go. The next task is to fit Midori

Midori with a GPS tracker so the team

team can monitor her after release. And

And this is nontoxic, right? Nontoxic,

Nontoxic, yes. What kind of data is this

this going to give you about Midori once

once she is in the wild? It gives us a

a top time, bottom time, dive time, water

water temperature, distance and salinity.

salinity. All in that. The most important

important thing about releasing a turtle

turtle is we want a health profile so

so we want to know that this turtle is

is diving and staying down there and feeding

feeding rather than doing short and shallow

shallow dives. With the tracker fitted,

fitted, Midori is transported 28 miles

miles off the coast to a reef.

Today is the culmination of two and

a half years of rehabilitation and thousands

thousands of hours of care. Ready? Step

Step forward. Stepping forward. Go.

Step forward. Stepping forward. Go. Yeah!

How are you feeling? Fantastic. What

a great release. That is to one half years

years in captivity and she has just gone

gone straight out. We can actually see

see what she is doing. She is a scientist

scientist for us.

scientist for us. What an incredibly special

special moment it was the release that

that Turtle, who is going to be joining

joining the other green sea turtles. Every

Every individual is so precious. That

That was the culmination is that a lot

lot of hard work on the part of a team,

team, it was special to be part of that.

that. We are over this beautiful green

green sea turtle off of the Jetty on Heron

Heron Island. It is a special thing to

to be sharing their stone with these majestic

majestic creatures. We have some of the

the tracking data from

Midori from the last 12 days or so.

She is sticking close to the place where

where she was released but that is not

not that unusual. Most rehabilitated and

and released titles tend to stay local

local for about ten days and then they

they start living further afield. She

She has been rehabilitated for two and

and a half years and it takes a while

while to get back into her stride. We

We cannot wait to see what she is going

going to do in the next few days. We will

will keep you updated. It is clear that

that higher migrations and wide-ranging

wide-ranging feeding habits will contribute

contribute to the health of the Great

Great Barrier Reef, just like those of

of the best green sea turtle I am sharing

sharing the ocean with now. Chris is in

in Mexico in the sky is looking for other

other majestic ocean wanderer.

other majestic ocean wanderer. We

We promised you a large marine mammals

mammals live and we have got one. You

You are looking at a giant man

You are looking at a giant man, what an

an extraordinary animal. These can have

have a wingspan of several metres and

and it is closing across the surface feeding

feeding on the plankton in these waters.

waters. The Sea of Cortez is a remarkable

remarkable place for wildlife. It is quite

quite big. 62,000 square miles of surface

surface and that is why we are taking

taking part in this aerial survey. We

We have Larry piloting the chopper. We

We have our wildlife cameraman bringing

bringing you these extraordinary pictures.

pictures. We have marine biologist Geraldine

Geraldine Busquet Vass. We have already

already seen something we can take off

off and marine survey. A great whale which

which is uncommon in this area but this

this winter we have had 53 whales which

which is surprising -- had five. They

They do not typically come in here but

but probably they have malnutrition so

so they are entering the Gulf trying to

to find some food. What about other whale

whale species? A far greater area than

than we would do on the surface, this

this is a great way of doing a census.

census. What are we seeing in blue whales?

whales? Around 300 blue whales but within

within the park on a 13 different individuals.

individuals. Yesterday I was seeing what

what are our chances of finding the blue

blue and you are offering a statistic

statistic of 99%. Are you going to revise

revise your off I govern we have so few

few animals in this area? I am going to

to go for 99%. We love Geraldine. She

She is so optimistic when it comes to

to finding things. That beautiful shot,

shot, look at that. We have scored with

with error Manta ray. One of the key things

things is that the Sea of Cortez offers

offers great opportunities for wildlife

wildlife spectacles. If you cast your

your mind back to Blue Planet II you might

might remember the mobulas that were found

found here, extraordinary groups of these

these animals coming together very densely

densely and performing these extraordinary

extraordinary leaps out of the water.

water. I never guess the thing that these

these things could throw themselves out

out of the water. They look amongst the

the least aerodynamic. These mobulas come

come together in huge numbers, bleeding

bleeding and mating and feeding, it is

is a great place for them to be together

together -- breeding. The other thing

thing we have seen are large numbers of

of dolphins together. The species we have

have been looking at me and they have

have been common dolphins and these typically

typically occur in groups of ten to 50

50 but sometimes you will get pods of

of up to 2000 of these dolphins. They

They will be searching the waters here

here for any sign of food. I was able

able to get close to them when we first

first came out. I went out on a boat and

and it is always thrilling to see them.

them. It is marvellous to watch how they

they twist and turn in the water. One

One thing they do typically if you are

are out whale watching is they will go

go bow-riding, using the pressure wave

wave of water being pushed by the boat

boat to push them through the water, so

so they are having an easy ride at the

the front. Unite think this is behaviour

behaviour they have adapted solely because

because they can utilise it in front of

of a boat but we have been doing aerial

aerial surveys and picked up amazing shots

shots of dolphins bow-riding blue whale.

whale. The blue whale is a huge animal,

animal, it is not very fast. They typically

typically move forward about 12 miles

miles another but I guess because of its

its bulk it is shifting water in front

front of it and the dolphins can take

take advantage of that body of water.

water. Not just a blue whales, we have

have also seen dolphins in front of Fenn

Fenn whales which has been an extraordinary

extraordinary thing to see. Dolphins are

are famed for being playful. We know that

that they are a very curious animal and

and if you cast your mind back to Blue

Blue Planet II you will know that we were

were watching one playing with Coral.

Coral. These days there are other entities

entities in the ocean, not just natural

natural things but things like plastic,

plastic, and this is what happens if dolphins

dolphins get involved playing with that.

that. Dolphins,

Dolphins, the acrobats of the sea. With

With over 30 species, from common dolphins

dolphins to spinners, they are present

present in almost every ocean around the

the world, including our coastlines. Travelling

Travelling in large pods with impressive

impressive displays of speed and agility.

agility. But it was this group of bottlenose

bottlenose dolphins from Blue Planet II

II that show as they are more playful

playful side.

playful side. Dropping and catching fragments

fragments of coral seems like a popular

popular pastime with these youngsters.

youngsters. These games are thought to

to develop their coordination and dexterity

dexterity that they will need when they

they start hunting in the open ocean.

ocean. Two years on, their behaviour hasn't

hasn't changed. But their playthings have.

have. Plastic. Although these dolphins

dolphins appear to be playing with it,

it, ingestion or entanglement can be deadly.

deadly. With 8 million tonnes still finding

finding its way into heresies each year

year animals are coming into contact with

with plastic on a daily basis. But there

there is hope. Since Blue Planet II the

the world has woken up to this threat.

threat. But thousands of organisations

organisations attempting to reverse the

the trend. More money is being spent on

on removing plastic than ever before.

before. From state-of-the-art technology

technology and the open seas to global

global beach planes. People are coming

coming together to read our oceans of

of plastic.

of plastic. Sometimes

Sometimes it takes seeing the effects

effects on marine mammals that we have

have such an emotional connection to to

to really make us sit up and take notice

notice and start to change our habits.

habits. I find it heartening so many people

people are already doing all they can

can to live better lives. In the Bahamas

Bahamas we have had incredible results

results seeing so many different kinds

kinds of sharks and rays. This is a shark

shark sanctuary. The animals are protected.

protected. Catching them is illegal but

but it is not the turquoise seas that

that is the reason they do so well, it

it is these spiderlike plants, mangroves.

mangroves. Our cameraman is down in the

the mangroves and has a camera under the

the water and we may have some baby sharks

sharks on the camera right now. And a

a few other fish as well. You can already

already see why these mangroves are so

so important. They are themselves a remarkable

remarkable plant so wait I am now is in

in tidal salt water. I was standing on

on the sand a couple of hours ago and

and right now it is up to my thighs and

and mangroves can shed salt through their

their rates and can reproduce using seed

seed pods like this which look like Cuban

Cuban cigars but it is a living tree that

that is cast onto the and will set up

up a mangrove elsewhere. There are lots

lots of different sharks travelling a

a long way to come to these mangroves,

mangroves, lemon sharks travelling 2000

2000 miles from the east Coast of America

America to come here to the mangroves.

mangroves. Why? They are a very special

special and important place indeed. This

This tangled mass of rates is the mangroves.

mangroves. It is an environment that changes

changes constantly with the tides throughout

throughout the day and provides the perfect

perfect spot for baby marine animals to

to hide out in. I am enjoying clemency

clemency to see another vital piece of

of the puzzle for maintaining a healthy

healthy population of sharks. Look at

at that. Yep, they are all waiting for

for us. Baby sharks. That is absolutely

absolutely incredible.

absolutely incredible. These are lemon

lemon sharks. They have been studied by

by researchers for over 30 years. It looks

looks like they want to be fed. Yeah,

Yeah, we have a little bit of squid if

if you want to give it a go. I would genuinely

genuinely loved her. How old are the sharks

sharks we are looking at? Most of them

them are in their first few years of life,

life, the majority will be two or three

three and the larger ones are four or

or five. That small narrow walkway we

we walked in the bigger sharks cannot

cannot use that. What are they taking

taking shelter from? The biggest predator

predator of ginger lemon sharks is adult

adult lemon sharks. They are cannibalistic.

cannibalistic. Also bull sharks and other

other species like that. This is a nursery

nursery where the youngsters are safe

safe from other... That went right between

between my legs! I should be waiting a

a cricket box or something! OK. Seriously.

Seriously. That went right between my

my legs. They must like you. That one

one day is a decent size. They will be

be pretty loyal to the mangroves they

they were Bourne end. They will be and

and they mangrove their entire life cycle.

cycle. What are the main threats to mangroves?

mangroves? We see the mangroves are being

being removed to build hotels and bigger

bigger resorts and that means that these

these will be using the same areas but

but they will not have the security. Lose

Lose the mangroves and you lose the lemon

lemon sharks. Yeah.

It may not look like any other

nursery you have seen before but you can

can see how vital this environment is

is to these rather wonderful and surprisingly

surprisingly cute animals. Quite

Quite lucky to have escaped that intact,

intact, I think! I hope to redress the

the balance on sharks this year is to

to try to convince people they can be

be cute and I think seeing those baby

baby sharks, they certainly can be. These

These mangroves, let's have another look

look at our live camera, is there anything

anything there? We've got a baby lemon

lemon shark right now, we've seen a couple

couple of them swimming together side

side by side. Lemon sharks have an ability

ability to form friendships, believe it

it or not. We've got to make together

together right now! These two animals

animals have been following each other

other all day, nose to tail. It is remarkably

remarkably cute but they are not the only

only animals that rely on mangroves. Egrets,

Egrets, herons, pelicans will nest in

in the trees, you have sponges all over

over the branches, as much as 80% of fish

fish rely at some point in their lives

lives directly or indirectly on mangroves

mangroves so this is an absolute paradise

paradise for wildlife. It is a bit more

more of a hard sell for us as human beings.

beings. It's often portrayed as being

being an environment that is a stinking,

stinking, stagnant swamp that is bug ridden.

ridden. And of course it is prime real

real estate with an ocean view so they

they are being cut down at a frightening

frightening rate. We've lost 30-50% of

of the world's mangroves in my lifetime.

lifetime. In the Americas they are being

being lost faster than tropical rainforests.

rainforests. If we lose them, then we

we face a life with seas that have simply

simply nothing in them. In the Bahamas,

Bahamas, that is not a problem because

because we have mangroves here and because

because of that we have fabulous seas.

seas. Let's see what is happening in the

the sea with Liz on the other side of

of the world. We

We have got fabulous seas as well here,

here, Steve Backshall, we are on the jetty

jetty of Heron Island. Look at that, beautiful,

beautiful, green sea turtles wandering

wandering around in the morning light,

light, jellies everywhere, we have rays

rays of all sorts, we have cowed tail,

tail, whiptail, we've also got lemon sharks,

sharks, black tip sharks, black tip sharks,

sharks, the most wonderful spot just off

off the jetty every morning we see a heck

heck of a lot of life and every species

species here is deeply reliant on the

the next, all of these animals are here

here to feed on the prey they need that

that is buried in the sand, if you are

are a ray, but also on the small fish

fish in the shallows if you are a juvenile

juvenile shark. The Great Barrier Reef

Reef is deeply connected, of course. Scientists

Scientists take to the often to get a

a better understanding of how all those

those connections work, so our coral expert

expert got a bird's eye view just a few

few ago.

First time I flew over a reef was in

the 1990s and I got a sense of the scale

scale of the whole reef. And what was

was really remarkable was just the incredible

incredible colours coming from the reef

reef system, these blue and turquoise

turquoise colours. It does something to

to me personally, it makes the hairs on

on the back of my neck stand up, I just

just react to that colour and for me it

it is like a spiritual home for the marine

marine world. I think the reef Edge, the

the scalloped edge, where you see the

the forces, the wave action coming in,

in, the wash moving through with all the

the nutrients coming into the reef system,

system, that is one of the most extraordinary

extraordinary owes. In terms of sheer

sheer beauty it is central part of the

the reef where you get all these intricately

intricately connected parts of the different

different reef systems, all the patchwork.

patchwork. One of the beautiful things

things about having the privilege of flying

flying over a reef system, it reinforces

reinforces how spectacularly beautiful

beautiful these systems are and I wish

wish everyone on the planet could see

see a healthy, functioning reef system.

system. Hopefully in the future there

there will be enough systems so that people

people can enjoy them. That

That looked incredibly special, Peter.

Peter. How much do you enjoy going up

up there? You had a big smile on your

your face. It's fantastic to get that

that perspective and to be able to see

see the magnificence of these reef systems.

systems. Why is it important for scientists

scientists to understand these connections?

connections? It is very important because

because when we are focusing on a reef,

reef, you look at these small-scale interactions

interactions and it's only when you get

get back in the air you remember these

these reef systems, although physically

physically separate, they are interconnected,

interconnected, and they are interconnected

interconnected through larvae dispersing

dispersing between them over time and,

and, therefore, you find that you get

get flow of energy and life between these

these different reef systems. How much

much do corals contribute to the connections

connections and animals? How much can

can corals travel from one part of the

the Great Barrier Reef, a 2300 kilometre

kilometre stretch of reef networks? It

It is immense and one of the things that

that is exciting about the research we've

we've been doing is that we are starting

starting to realise these connections

connections are very large scale. You

You can get some coral larvae and fish

fish juvenile that recruit into different

different parts of the reef system, dispersing

dispersing from one reef over tens of

of thousands of kilometres. Hundreds of

of kilometres? Hundreds and sometimes

sometimes thousands of kilometres which

which explains why so many of the organisms

organisms we see on some of the reefs

reefs on the Great Barrier Reef are found

found in other parts of the world. And

And we see so much life here, the turtles,

turtles, the sharks, the rays, we have

have live shots of the rays and the pre-recorded

pre-recorded footage of what has happened

happened since we arrived here. It's teeming

teeming with life and they are important

important for the connectivity of the

the Great Barrier Reef, aren't they? Absolutely

Absolutely and one of the fascinating

fascinating things as it is not only the

the reefs, it is other organisms moving

moving between different habitat so for

for example some fish start off in the

the nursery areas and mangroves, then

then they migrate to seagrass beds, then

then to the inshore reefs, than outer

outer reefs. So, all of these flows between

between reefs systems, it shows as they

they are interconnected. It so fascinating,

fascinating, the more we learn about this

this reef, the more incredibly awe-inspiring

awe-inspiring it is. It is thanks to these

these aerial surveys we can understand

understand the interconnectivity and into

into reliance on everything of it but

but all of our oceans ecosystem is the

the world over are connected. One healthy

healthy ecosystem will affect the health

health of the next, it is one Blue Planet,

Planet, one, living, breathing organism.

organism. Chris is still in the skies.

skies. Well,

Well, here we are, hovering above the

the Sea of Cortez this afternoon conducting

conducting our aerial survey. If you are

are watching earlier, you saw we had that

that fabulous manta ray. I think Florian

Florian has the beautiful view but there

there isn't much down there, we are failing

failing in our quest to find anything.

anything. Florian is working hard, Larry

Larry can't take his eye off the sea and

and Geraldine is counting everything we

we find. Not finding things is as important

important as finding things, isn't it?

it? Negative data is important. When you

you don't see things, you know they are

are not distributed there which is the

the point of doing the survey, to know

know who is there, when it is there and

and what types of species we can see.

see. I'm sorry to tease you but are you

you sticking to a 99% chance of a blue

blue whale? Come on, Chris! We saw a manta

manta rays and a grey whale, what else

else do you want? We've had some successes

successes so far, no doubt. Another thing

thing we have seen from up here are mass

mass feeding events, and, typically the

the queue for this that leads to them

them are dolphins on the surface of the

the water and we see these animals speeding

speeding towards their food. Now, typically,

typically, the animals we have been looking

looking at have been common dolphins,

dolphins, short beaked and long beak difficult

difficult to tell apart but you can see

see that classic hourglass pattern and

and they look like they are travelling

travelling incredibly fast but, in fact,

fact, their fastest speed is 37 miles

miles an hour. As soon as they get into

into the bait ball, they get excited,

excited, they stir things up, they can

can press the fish together which means

means it is easily spotted by birds, and

and it is then that we start to see the

the pelicans arriving. They will come

come from great distances across the sea,

sea, honing in on this rich source of

of food. One pelican watches another,

another, which watches another, which

which watches another, so an network aggregates

aggregates in this area. They will plunge

plunge into the water from about 60 feet

feet high, they come in at about 60 or

or 90 degrees, and they dive down only

only a couple of metres, not far beneath

beneath the surface. Just like gannets

gannets in the UK, they are specially

specially evolved for this, their beak

beak breaks their entry into the water

water and their body is covered with airbags,

airbags, if you like, to cushion the view

view as they hit the water, cushion the

the impact as they get into it. Then,

Then, of course, other animals will come

come because this is such a rich source

source of food. And the last visitors

visitors and the slowest moving, these

these can be the large whales. Here you

you can see a whale coming up from beneath

beneath that mass of fish, probably anchovies

anchovies and sardines, and filling its

its huge, expanded mouth. You can see

see that very characteristic pimply face

face of the humpback whale. And humpbacks

humpbacks like this are typically attending

attending these sorts of compressed shoals

shoals of fish that we call bait balls.

balls. Absolutely fantastic! And, now,

now, I'm looking down, we have some live

live dolphins here, we have a view live

live from our chopper in the Sea of Cortez,

Cortez, a bit of activity but they don't

don't seem to be moving quite so fast

fast as normal. We will try to get closer

closer to them. When we were out earlier,

earlier, it wasn't just the dolphins we

we were looking at, we were extremely

extremely fortunate to find the world's

world's largest fish. Yes, we found a

a whale shark. Just to look at theirs.

theirs. What a beautiful animal! Not a

a large fish feeder, they eat small fish,

fish, but they are swimming along on the

the surface in these warm waters with

with their mouth wide open because they

they are filtering the water for plankton.

plankton. It is an extraordinary opportunity

opportunity to see one of these beautiful

beautiful animals. Now, you can find them

them all over the world in warm waters

waters but they remain a mystery. Cast

Cast your mind back to Blue Planet II,

II, they thought they might have found

found for the very first time at the beginning

beginning of the 21st century, the place

place where these animals go to breed.

breed. As it turned out, that wasn't the

the case but they have been back on the

the case and, as you'll see here, the

the scientists have found another lead.

lead. At

At up to 12 metres long, whale sharks

sharks are the largest fish on the planet.

planet. They can live for 100 years, cruising

cruising our seas in search of plankton

plankton and tiny fish.

plankton and tiny fish. Solitary giants,

giants, they cross oceans, and maybe even

even swim around the entire globe. But

But this lonely lifestyle makes them really

really hard to study. One of the things

things that interest me about whale sharks

sharks is how little we know about their

their adult phase of their life so once

once the sharks hit adulthood at about

about eight or nine metres, how they usually

usually disappear off into the open ocean.

ocean. Now scientists from around the

the globe are trying to figure out how

how to protect these gentle giants, which

which means answering questions like where

where these enormous fish breed. If you

you want to protect a species, you have

have to answer these fundamental questions

questions about its life history that

that seems simple but have stumped scientists

scientists for years. Blue Planet to revealed

revealed a large group of females thought

thought to be pregnant in the Galapagos.

Galapagos. But the scientists were back

back to square one when recent underwater

underwater ultrasounds revealed they were

were not pregnant at all, just fattening

fattening up in the bountiful waters there.

there. Now the same team are shipping

shipping their attention to another site.

site. Just off the coast of Saint Helena,

Helena, a British island in the middle

middle of the Atlantic Ocean, they are

are investigating a gathering of male

male and female adult male sharks that

that dish - Mike whale sharks and they

they think they found their breeding grounds.

grounds. There's only one pregnant female

female that's ever been examined so the

the fact there are adult males and females

females is something we want chase up.

up. What finding as you have this 50-50

50-50 ratio of mature males and females

females which put strength behind the

the theory that Saint Helena is the place

place where mature adults will come and

and come and mate and breed. And if this

this is the case, this discovery could

could bring us one step closer to protecting

protecting these extraordinary fish for

for the future. People often ask why we

we are doing the research, why do we need

need to understand where they breed, where

where they go, which sites are they using.

using. Once we know this information,

information, we can better inform management

management measures and protect the species.

What about that! Extraordinary!

Saint Helena! Maybe that is where they

they are all going, all the whale sharks

sharks going to Saint Helena? Absolutely

Absolutely amazing. We've been doing the

the aerial survey and we have a couple

couple of dolphins down there, which are

are not quite the blue whale we are looking

looking for but nevertheless it's great

great to see these animals live on TV.

TV. They are on the surface but this week

week we have been very pleased to have

have been partnering with the Woods Hole

Hole Oceanographic Institute, who offer

offer a service to us of being able to

to dive much deeper under the water. We

We are going over now to talk to Andy

Andy Bowen, the director of the US National

National Deep Sea Submergence Facility

Facility and he is on board the RV Atlantis

Atlantis with their submersible Alvin

Alvin off the coast of California, Andy,

Andy, how are things going on? Welcome

Welcome aboard the research vessel Atlantis.

Atlantis. We have a fantastic day for

for diving and, actually, we are just

just in the final stages of recovering

recovering our research submersible, Alvin.

Alvin. Yesterday, it dived to the top

top of a seamount 1000 metres below us

us with the objective of surveying the

the ecosystem there, the glass sponges,

sponges, crabs, and deep sea corals, and

and their distribution. Chad King was

was on board the Alvin and had the opportunity

opportunity to see with his own eyes through

through the viewport is the unique ocean

ocean environment. Humans are still effective

effective at engaging this. This, for

for example, is a deep sea bubble gum

gum coral, which is actually half the

the size of the Alvin submersible and

and centuries-old. Please come back, we've

we've got plenty more dives during this

this expedition. Chad and I will be talking

talking about the unique recently discovered

discovered footage.

Thank you. Other team have to leave

the Atlantis with some urgency because

because the boat is heading out into the

the Pacific and that they do not leave

leave now they are going to be stuck on

on it for two months. We will be getting

getting more in the final show on Sunday.

Sunday. One of the greatest rates in marine

marine biology has been a better understanding

understanding of where sharks go and the

the people I have been working with here

here have been instrumental in ever greater

greater understanding and knowledge of

of the movements of these animals that

that once were a complete mystery. I have

have been working across the sea in Florida

Florida with some of their scientific

scientific colleagues in just over a week

week ago I was there and I took the flight

flight of my life.

flight of my life. This

This is Palm Beach, Florida. It is a playground

playground for the rich and famous but

but do they know that off the coast is

is one of the greatest gatherings of large

large predators on the planet?

large predators on the planet? Each year,

year, thousands of black tip sharks gather

gather here before migrating north to

to their summer feeding grounds almost

almost 4000 miles away off the coast of

of North Carolina. They are followed by

by larger predatory sharks including hammerheads,

hammerheads, which grows in from deeper

deeper waters to feast on the mass gathering

gathering of black tips. I have joined

joined Stevie, a professor at Florida

Florida Atlantic University. Each year

year he takes to the monitor this extraordinary

extraordinary natural spectacle. Just

Just a slick of sharks going on all the

the way parallel to the coast. That is

is absolutely fantastic. They stand out

out so well against the sandy bottom.

bottom. That is one of the reasons we

we are so successful with the surveys,

surveys, clear water, white sandy bottom,

bottom, you can see everything. And they

they are shallow. They make it easy for

for you. Are you getting a sense of how

how the numbers are changing over time?

time? We have been doing these surveys

surveys for the last nine years and we

we have seen this decline in the number

number of sharks. At the same time we

we have seen an increase in the water

water temperature down here. They have

have narrow thermal tolerance. They like

like water between 21 and 25 Celsius and

and has water temperatures are rising

rising you are getting fewer sharks this

this far south. The black tips you have

have got here, there are constant interactions

interactions between those and the larger

larger predatory sharks. How is that likely

likely to be affected? If you do not have

have these black tips sweeping down, tens

tens of thousands every spring, there

there is no food for the big hammerheads

hammerheads and the black tips are not

not eating may fetch so we do not know

know what might happen. Global seed temperatures

temperatures have increased by 1 degrees

degrees in the last 50 years. While that

that does not sound like a lot the knock-on

knock-on effects can be seen in our oceans.

oceans. These ecosystems remain pretty

pretty much unchanged for millennia but

but they are dramatically changing in

in my lifetime and where that will lead

lead we simply do not know. What

What incredible images for a shark lover,

lover, that must have been a dream come

come true. For a healthy reef you need

need ocean fetters beneath the surface

surface to be healthy and goes above the

the surface to be healthy including the

the sea birds that come here during the

the breeding season. Kingfishers, silver

silver gulls and the fluffy chicks we

we are trying not to tread on, there are

are so many of them, Eastern egrets and

and the eastern golden glove that comes

comes all the way from Siberia. By far

far the greatest numbers are disease,

disease, the black noddies. This nest

nest is made of carefully picked out twigs

twigs and bird to. We have these wedge

wedge tailed shearwaters. It is a beautiful

beautiful place to appreciate sea birds

birds and their importance to the reef

reef simply cannot be overestimated so

so joining me is a doctor from the University

University of Tasmania to tell me more.

more. You are a sea bird expert. Tell

Tell me about how important sea birds

birds are to reef ecosystems. Critical.

Critical. As the birds are foraging out

out on the open ocean over may be hundreds

hundreds of kilometres fish and squid,

squid, they bring that nutrition from

from the fish and squid back to these

these islands like Heron and they deposited

deposited and it is built up in the nests

nests and we are trying to avoid it. Live

Live on TV. Just on Heron 45 tonnes every

every year. Just from the black noddies.

noddies. That is a lot of bird excrement.

excrement. And it is beneficial nutrients

nutrients like nitrogen and phosphorus.

phosphorus. It is not just the island,

island, it is the reef out there. Those

Those nutrients flow from the island out

out onto the reef and this is where things

things start to get really exciting. New

New research is showing those nutrients

nutrients are fundamental to fish growth

growth so they're more nutrients you have

have the bigger the fish and the faster

faster they grow and the more of them.

them. You have more corals growing faster

faster and probably most important those

those corals have more resilience. So

So if we have a climate event may be the

the nutrients could actually help the

the corals resist that climate change.

change. Birds are helping corals to manage

manage rising sea temperatures. That is

is how interconnected everything here

here is. It is one of your areas of expertise

expertise and research that there is a

a lot of plastic in our oceans and birds

birds are picking up plastic when they

they are trying to feed. What does this

this mean for populations? They are not

not just bringing back fish and squid

squid and the good stuff, they are also

also bringing back the bad stuff. In the

the Great Barrier Reef shearwaters contain

contain on average 25% of them contain

contain plastic so this is a perfect example.

example. This is plastic from a wedge

wedge tailed shearwater's stomach. We

We do not want this in the birds. They

They deposited onto the islands. So they

they are also leaving plastic on the islands.

islands. Absolutely. The birds are not

not just the link between sea and land

land for good stuff, it is also for bad

bad stuff. What does this mean for sea

sea birds especially considering how many

many different ecosystems they visit?

visit? Around the world sea birds are

are declining faster than any other bird

bird group. This is very worrying for

for the health of the oceans and for our

our islands. With their decline, less

less nutrients but some bright spots with

with shearwaters doing great. There is

is light in the story but we can all play

play a part particularly with plastic.

plastic. Each individual can show the

the planet that we care by changing our

our plastics habits. I cannot wait to

to show you on Sunday the extraordinary

extraordinary work that scientists are

are carrying out here. Some mind blowing

blowing stuff to show you when it comes

comes to giving the reefs a lifeline.

lifeline. It is time to go back to Chris.

Chris. Sadly

Sadly we are running out of time on the

the aerial survey over the Sea of Cortez

Cortez but I think it has been successful.

successful. We did not find a blue whale

whale but we saw a grey whale which is

is an unusual sighting. Of course we had

had the whale shark which is fantastic

fantastic and we are following this giant

giant man

giant man Manta ray. Many of the species

species have been fish feeders. We saw

saw those feeding frenzy is with the whales

whales and the dolphins.

whales and the dolphins. We have seen

seen sardine fishermen out plying their

their trade. Globally each year somewhere

somewhere between one and three Chilean

Chilean fish are caught by our fishermen.

fishermen. 10% of them are thrown back

back in. Here in the Sea of Cortez 85%

85% of the fish stocks are being overexploited

overexploited and when it comes to things

things like sardines 80% of them are being

being used to produce fish pellets and

and those fish pellets are fed to animals

animals or they go for pet food. There

There are solutions and there has been

been a solution affected here. There is

is a place on the south of this peninsula,

peninsula, quite a small area, 95 square

square kilometres, and in the ten years

years following it being protected, the

the fish biomass quadrupled and you can

can see there are huge numbers of fish

fish that have come back here. It is a

a place for the apex predators to return

return as well. It has paid dividends

dividends for fishermen because they are

are making far more money out of ecotourism

ecotourism by leading divers to the site

site than they were making when they were

were fishing it in the first place. Plenty

Plenty of marine protected areas around

around the world. The largest is in Antarctica.

Antarctica. There is a giant one around

around Hawaii. Just last week the British

British government declared a Marine Protected

Protected Area around the middle of the

the Atlantic with no less than 90,000

90,000 square miles. Top work. These marine

marine protected areas are a good idea

idea but we need no take zones in them,

them, no doubt about it. That is about

about all we have got time for. I will

will be back tomorrow with another great

great success story. I am going to give

give you a clue. Which song was featured

featured on the single largest pressing

pressing of an LP record in the history

history of the music business? You will

will find out tomorrow. Until then, over

over to Steve.

over to Steve. I

I could not agree more. Coming up another

another final show... We are on the search

search for humpback whales. The Great

Great Barrier Reef as you have never seen

seen it before. And I will be diving with

with these guys live. There is nothing

nothing else quite like the hammerhead

hammerhead shark.

That is one of the great wildlife

encounters on planet Earth.

encounters on planet Earth. Yes, our final

final show on Sunday at 8pm on BBC One.

One. Please tune in. Our planet, worth

worth fighting for, wild and wondrous.

wondrous. The Open University has produced

produced a free booklet exploring the

the human impact on our oceans including

including a tater guide to the different

different types of plastic that could

could be recycled. To order, please call

call or go to the website.

Follow the links to the Open University.