Horizon (1964–…): Season 47, Episode 2 - The Death of the Oceans? - full transcript
Sir David Attenborough reveals the findings of an investigation into what is happening to our oceans, and looks at whether it is it too late to save their remarkable biodiversity.
For thousands of years,
the world's oceans have held a
special place in our imagination.
Without them,
life would never have come about.
We're only really waking up
to how important the ocean
is for life on this planet.
Today, some four billion years after
they formed, our oceans continue
to dictate life on earth.
Oceans are absolutely critical.
There's billions of people around
the planet who are dependent on the
resources that we get from oceans.
But this most precious of assets
has never been under greater threat.
As the human population
nears seven billion, so our
oceans are struggling to cope.
It's quite clear that humans
have had a profound impact
on this eco-system - we are talking
now about an unnatural ocean.
If we haven't massive changes to the
oceans and, and how they function,
it could have really direct impacts
on humans and their societies.
With time running out,
marine scientists around the world
have been working as never before...
Seventy five in the water,
we're fishing.
..to save this vital eco-system.
We really do risk losing
species before we've even
been introduced to them.
But is it too late?
The living ocean is very fragile,
and don't for a minute believe
that we can't screw it up
much worse than it is today.
Spread over an area of 360 million
square kilometres,
the world's oceans cover
more than 70% of our planet.
So large is their volume,
that almost all of
the earth's available
living space consists of water.
It's one of the great
contradictions of the oceans,
that although they
lie all around us,
they remain the most mysterious
of the earth's eco-systems.
What's living just out there is
hidden from the sight of most of us.
But in recent years, our
understanding of this vast habitat
has begun to increase,
thanks, in part,
to one of the most ambitious,
inspiring, not to say timely,
scientific projects of my lifetime.
Called The Census of Marine Life,
its goal has been to compile the
most comprehensive list, to date,
of life in our oceans,
from the largest of mammals,
to the tiniest of microbes.
There have been few explorations of
the ocean on a par with this census.
Um, the only thing that I can think
of that really is like that, are the,
you know, the great exploratory
voyages of hundreds of years ago.
Involving over 2,000 scientists,
from almost 90 countries,
it's used the latest technology
to explore and document some of
the ocean's most remote regions.
There's never been as big a project
looking at the natural world.
And we census human populations,
we understand about
how many trees grow on the land,
but we have never, ever had
a baseline survey of what
actually lives in the oceans.
Literally the oceans are the support
system for all life on earth.
And if you don't care about the
oceans, then you're basically saying,
I don't care about
what happens to life on earth.
What the census amounts to is a
completely new biography of this,
the largest habitat on earth.
Not only has it increased our
knowledge of WHAT lives there,
but it also enhances
our understanding of how
that life keeps the planet alive.
Today, the health of the oceans
is in danger as never before,
and it could well be
that the census
could prove to be a vital tool
in safeguarding their future.
For the last five years, marine
biologist Dr Julian Caley has
been overseeing a unique project,
whose results have formed
an invaluable part of the census.
The aim of this project?
To catalogue the diversity
of the most complex eco-system
in the ocean - coral reefs.
A task so huge that it has
called for a new and innovative
way of collecting evidence.
This morning, Julian
is heading out to a long,
thin stretch of coral reef,
called Ningaloo
in Western Australia,
to recover some of that evidence.
Coral reefs host more biodiversity
than any other system in the ocean.
People appreciate the diversity
of the rainforest, but we don't
know about the diversity of reefs to
the same extent, and it's because we
haven't had the opportunity
to get out
and actually start
sampling all that biodiversity.
Together with dive buddy
Greg Coleman, Julian will be
descending to a depth of ten metres,
to retrieve a small plastic box
that's been attached to the sea
floor for the past twelve months.
OK, this is what we're
out here today to collect,
this is what we call an ARMS,
it stands for Autonomous
Reef Monitoring Structure.
It's a simple design that we can
replicate, and the purpose of it
is to provide some structure,
that we can take these down, we
can put them on, on the reef, and
things will come and live in them.
A simple, but ingenious design
that has helped Julian and his team
to retrieve countless thousands
of specimens from the sea bed.
After a thorough search of the area,
Julian and Greg eventually find
what they've been looking for,
quickly covering the ARMS
with a second box, to prevent
any creatures inside from escaping.
And with the ARMS safely on board,
the team head back to the lab.
Just a stone's throw from the
shoreline, the low-tech surroundings
of a rundown sheep station
double up as a makeshift laboratory.
We might just need a bit more
water in there. Yeah, we're
going to need some more water.
This one looks like it's got maybe
a bit more life on it than some of
the previous ones we've pulled up.
Here, work gets underway,
dismantling the reef-monitoring
structure.
We want to get everything
out of it, there might be a few
creatures still living in there.
So far, the project has recovered
almost two hundred of these boxes,
each one containing a
cross section of reef life.
As we dismantle these, we could
expect to find anywhere up to
hundreds of different species,
lots of which probably would be
invisible to the naked eye,
but that taxonomists can identify
with a microscope later on.
Ooh, brittle star. We find a
whole range of different life,
from the algae, the crustaceans,
brittle stars, there's obviously
the colonial animals, like
the corals, and the soft corals,
and the bryozoans.
It's a real snapshot
of the biodiversity of the place.
But collecting all this biodiversity
is only the first step.
The next is to identify it.
Every time one of these boxes
come up, or coral rubble samples
come up, it's an adventure.
There are so many different
tiny invertebrates that live
in the cracks and crevices
of algaes and corals.
These animals I work with, these
polychaete worms are very small,
sort of,
one to about ten millimetres.
Within this genus, there's only one
species that has been recorded,
in the 1970s.
I, so far, have found 22 new
species, belonging to this genus.
I focus on the seaweeds
and the algae.
And in algae,
I work with macroalgae
and we go, dive, and snorkel,
and collect everything we find.
So far I think we have 70 species.
We're part of a group with
The Census of Marine Life,
who's looking at marine parasites.
And what we look at are
the parasitic organisms
that live in the internal organs
and tissues of various reef fish.
Just about every day we'll find a new
species. There's a lot of work to do,
many, many lifetimes.
To date, the coral reef project
has identified more than
1,000 likely new species,
a number that rises to an estimated
6,000 across the census as a whole.
The census has really uncovered not
only new species and new life forms,
but just new understanding of
where they live and how they live.
And so it's everything from microbes,
to understanding connections between
small crustaceans, to finding new
species of fish and squids,
that have been quite remarkable,
and it's literally thousands
of new species,
in dozens of new environments.
But as these remarkable discoveries
are enhancing our knowledge
of what lives in the oceans,
and where, time is passing
only too swiftly.
It's one of the ironies
of marine research that,
as we discover more and more about
the oceans and what lives there,
more and more of it is disappearing.
And the reason for that,
of course, is us.
I think all the threats to the
ocean at the moment are man-made.
There's no question that humans
are eco-system engineers now.
Recent studies have found that there
aren't any places left on earth
where humans are not impacting
the ocean environment.
And there is perhaps no single human
activity that poses a more immediate
threat to marine diversity
than commercial fishing.
But with an increasing human
population, more and more dependent
upon the oceans for our food,
how are we to control
how much we take from them?
Here, in the fishing port of
New Bedford, in Massachusetts,
the nature of the problem
soon becomes apparent.
Like many other communities
in this part of the world,
fishing has been a fundamental part
of daily life for hundreds of years.
Do what you can, get us as much
as you can and we'll go from there.
At the local processing plant,
table fish, such as cod and flounder,
are de-scaled, filleted and packed
up for markets throughout the world.
50,000 plus for Monday?
Beautiful, beautiful.
The company has been run
by the Barrie family
for the last hundred years.
Welcome to the Pier Fish Company.
We employ approximately
about 100 people.
My grandfather started the business
in 1910, in the waterfront of Boston.
Snow white, just like my baby's butt
when, when he was born. Beautiful.
Every day, up to 90,000
kilograms of fish pass
through these doors.
A seemingly never-ending
conveyor belt of marine life.
But appearances can be deceptive,
because while stocks
might look plentiful,
companies like Pier Fish
are now having to source that stock
from further and further afield.
What's the update on, um,
the Courageous, as of today?
He's fishing in a barren sea.
Good Chris, good, good, we
appreciate that, we appreciate that.
From a 100% of our
production from domestic markets,
I'd say right now it's about 15%.
The rest is all imported
from out of the country,
or other parts of the country.
These days everything's coming in by
factory trawler, by rail car,
over the road by truck, it comes
from China, it comes from Indonesia,
it comes from Vietnam,
it, it, Russia, it, coming from
all over the world now.
While some of this change can be
attributed to the demand for ever
more exotic species,
it doesn't hide the fact
that fish stocks globally
have been drying up for decades.
And what's brought this about
is technology.
A combination of giant factory
ships, hi-tech sonar and nets
as long as sixty kilometres,
have enabled us to
plunder the seas at will.
Air transit and Styrofoam cooler
boxes have made any kind of living
creature from the sea
available anywhere else in the
world, in 24 hours, and it's
that sort of pressure
that is simply
not sustainable going forward.
Confronted with this technological
onslaught, many species have
reached the point of collapse.
In 2003, researchers from
the Census published a paper
in the science journal Nature,
comparing fish numbers
with those of 1950.
What they concluded was that
in a little over fifty years,
90% of top predators,
such as tuna, shark,
and marlin,
had been fished from the sea.
It's a predictable pattern in a
sense, things that reproduce slowly
are likely to be more vulnerable
if they're under
intense fishing pressure.
And it's a pattern that has
consequences for all ocean life,
owing to the nature of
the marine eco-system itself.
A lot of people would be familiar
with the term "food chain" - it's
one of those things that,
it's very evocative, you know,
the little thing that gets eaten by
the bigger thing,
gets eaten by the even bigger thing.
But in reality, most marine systems
are much more like a food web.
What you end up doing is, if
you take out a whole bunch of the
individuals from a particular level
in that, in that trophic
web, you can affect change
within the rest of the web.
And not necessarily
change for the better.
We can't imagine
that these systems function in
a linear way, they just don't.
And so we don't know, if you push
here, what actually happens there.
We do know that if you
keep catching all the fish, shooting
all the whales and seals,
netting all the birds, and taking
them out of the system, ultimately
you'll be left with copepods
and bacteria and some
other things, that won't make
the picture as pretty.
In one of the most disturbing pieces
of research commissions by the
census, the question was asked,
"How much longer can our oceans
tolerate the present level
of commercial fishing?"
The answer was simple and stark -
if present trends continue,
commercial fishing as we know it
will have collapsed
by the year 2050.
An outcome so catastrophic
that marine scientists have been at
the forefront of efforts
to manage remaining fish stocks,
before some species are
lost for good.
Massachusetts Bay,
in the north west Atlantic.
Hey, you're good to go.
Clear.
Onboard the fishing trawler,
Gloria Michele, the crew are letting
out their first net of the day.
Just another fishing vessel
going about her daily business.
Last 25.
But what sets this boat apart from
the vast majority of other trawlers,
is that she's using a type of net
that has been declared illegal.
Made from a very fine mesh, its
sole purpose is to catch whatever
is out there, regardless of size.
First mate, Carl Rhodes, is hopeful
it will ensure a good haul.
Sometimes we catch big torpedo rays,
and some of the larger animals too,
sculpins, sea robins,
just all kinds of fish that live
closer to the bottom.
At 50 metres down, the
winching mechanism comes to a halt.
75 in the water, we're fishing.
And the wait begins.
On a given signal,
the net is finally hauled in.
But as its contents spill out
onto the deck, it's clear
that this will be no bumper payday.
The last three days, all the
catches have been a little light.
While a catch this small would
normally be a disappointment,
for the Gloria Michele and her crew,
it's not a concern.
Because she isn't out here to turn a
profit. Instead, she's fishing for
an altogether different reason.
Who's got the little whiting bucket?
As part of a scientific survey
of fish stocks in the area.
For scientist Matt Camisa,
it's vital that each trawl
is exactly like the last.
The most important thing we do is we,
we do the same sampling technique,
the same methods, the same gear,
ah, consistently.
Consistency is the key, if you
keep it consistent, you can
look at the trends over time
and know that you haven't
influenced that trend.
Two hours later, the
Gloria Michele is in position
over her next survey site,
and the whole process begins again.
These are winter flounder, a lot
of people fish for these around here.
So what we're going to
do is, now that we have
the weight on all of these,
we're going to take
the lengths on them,
some of them have to be
sampled, we'll cut them open,
determine the sex and maturity.
These are the otoliths, or the ear
bones, they have rings on them, like
rings of a tree,
that's what they use to age them.
Determining the age of each fish
is crucial to the survey,
because only by getting an idea of
juvenile numbers, can the scientists
estimate how plentiful fish
stocks will be in the future.
All of our data, the
State Inshore Trawl survey data
gets fed to the Federal database,
which is used, to do all
these, ah, stock assessments
on all these various species.
And what, after they've done all
these stock assessments,
they make the management regulations
and all the decisions on what
fisherman can and can't do,
when they can catch them, how much
they can take, that's very valuable.
So valuable that some species
have actually begun to bounce back.
Certainly some stocks have rebounded.
We've had a fluke, a good
rebound in our fluke resource,
that's not something we're seeing
here today, but, yellowtail
resource is doing quite well also.
It's a mixed bag, some species have
gone up and others have gone down.
In fact, it's been estimated that
in American waters, where management
strategies have been implemented,
almost 50% of fish stocks have
shown some sort of increase.
But while this might be grounds for
hope, it raises another question,
which is exactly how productive
should we expect our oceans to be?
A question to which the answer
lies back in time.
Professor Jeff Bolster has been
part of a census-led project
documenting the history of
commercial fishing in New England.
Caught 4,760. Caught 1,600.
Caught 2,300 fish.
Caught 1,000 fish.
Caught 5,500 fish.
Caught 3,000, 24,000, 70,000
80,000, 100...
It's impossible to imagine the
coast of New England without
imagining commercial fishing,
This is the
oldest profession in America,
and it's one that
is threatened today,
but is woven into
these communities,
in a way that is deeply, deeply
part of their essence.
By trawling through
the historical record,
Jeff has become convinced that the
key to the future productivity
of the oceans lies in the past.
Every European that came here
wrote with astonishment about
the nature of the eco-system.
And the point is that they weren't
comparing it to the Caribbean, or,
or the exotic East Indies,
where all the fish were different,
they were comparing it to
their own back yard,
it was salmon and herring and skate,
everything they were familiar
with, but the numbers were colossal.
Just how colossal
is apparent from even the most
cursory examination of the record.
Monday, 4th day of July, 1859.
This day begins with light
winds and calm, and continues
throughout the day.
Thus ends the glorious 4th,
by all hands toiling hard in fishing,
and caught 2,700 codfish.
This is the log of the Schooner
Mahalia from Newburyport,
just down the road.
They're catching cod, the numbers
are phenomenal,
they've come in to spawn, and then
once the spawning is done, these
men are catching them.
The daily catch is
here for each man,
I mean we have one man caught
472 fish, another man 461,
403, 410, 390,
So, again, this is a
significant number of fish.
Using these historical figures,
Jeff has been able to compare
past cod numbers with present.
The annual catches today in the
entire gulf of Maine are
about 4,000 metric tonnes,
if you exclude the
recreational catch.
But, in 1861, 70,000 tonnes,
hand lining, little sail boats,
today 4,000 tonnes,
big modern steel ships, electronic
fish finders, navigation system.
So the system has
changed profoundly.
By showing the marine eco-system
as it once was, Jeff hopes to change
perceptions of what constitutes
a healthy fish population today.
I mean if you imagine, sort of the
pathetic graph of fish landings,
is that goes
down, down, down, down, down.
And around 1990, around
here, it bottoms out,
and now there's an uptick,
OK, there's an uptick and it's good.
And what people sometimes say is
well, look, there's more fish now
than there used to be,
because they're talking about now
compared to 20 years ago, right?
But they need to think about the
scale, the uptick is tiny, and what
we've had is this huge descent.
And what our group is doing, by
providing that historical
perspective,
is saying we need to look at
this eco-system through time.
But setting targets based on the
number of fish that used
to live in the oceans,
doesn't mean that we can
just expect to turn back the clock.
We don't know if it can be
as good again as it once was,
we don't even know if it can be as
good again 100 years out,
as it was 100 years back.
But to not try,
I think, is really short sighted.
We don't want to think about, you
know, matters in the environment
as if we're going to go back to some
pristine state, or even go back to,
you know, the
conditions 100 years ago.
Um, you know, eco-systems change,
human activities change, and so on.
But that doesn't mean that we
should ignore at least the potential
for oceans to produce, um,
you know, a greater
abundance of fish.
Whether or not the oceans
can ever again be as productive
as they once were,
is a question that
scientists can't yet answer.
But they are sure of one thing -
if we are to save the commercially
important species of fish
that are currently under threat
of extinction, we must act
with the data we now have.
Do nothing,
and the implications are inevitable,
the loss of dozens of species
of marine fish round the world.
But on the other side of the world,
there are habitats that
are facing a threat,
the implications of which
scientists are only just
beginning to work out.
At the southern tip of Australia's
Great Barrier Reef, lies the
tiny coral quay of Heron Island.
A designated national park,
its crystal clear waters have
been attracting tourists
for almost 80 years.
But these waters also contain clues,
which suggest that by the time
another 80 years is up,
they will have changed
beyond all recognition.
Well, it looks like
it has survived the night.
Today, Professor Ove Hoegh-Guldberg
from the University of Queensland,
is launching a unique experiment
to monitor how this change
will affect coral reefs.
In 2006, Ove took part
in a BBC documentary,
following the effects of
global warning on the reef.
When I come here and see this,
this really stressed-out reef,
I find myself getting
really concerned.
It's another reminder that
there are huge changes on
the way with climate change.
Everywhere I look,
all I can see is bleached corals,
corals that are normally brown,
are now glowing a brilliant white.
This is because of the
algae having left the tissues,
all that's left are the
absolutely reflective skeletons.
Four years ago we were looking at
the impacts of
temperature on coral reefs,
and that's where we've had rising
ocean temperatures
and mass coral bleaching that's
threatening the entire eco-system.
But since that time,
there's now the realisation that
there are even larger forces at play,
and that these forces are combining
with things like temperature,
to make a very gloomy
future for coral reefs.
The cause of this new
concern is an environmental
impact with the potential
to be every bit as disastrous for
reefs as rising sea temperatures...
ocean acidification.
For billions of years,
the oceans have played a vital role
in keeping the earth's
carbon dioxide levels in check.
The ocean's involved in a huge
conveyor belt of sort of a chemical
reactor, if you like,
in which CO2 goes into the ocean,
it's fixed by plants, it may
be deposited as calcium carbonate,
and through these
very, very large scale circulations
of water on our planet, it's
essentially processing the atmosphere
and keeping our planet habitable.
And of course, we're only
just starting to realise that this is
actually what we live off,
it's the ocean.
But since 1960,
carbon dioxide levels in the
atmosphere have risen by almost 20%,
and by roughly 30% since the start
of industrialisation.
Like all things,
oceans have a capacity.
So as we've been pumping CO2
into the atmosphere by the
burning of fossil fuels,
we've actually started to exceed
the capacity of the ocean to
absorb that carbon dioxide.
One by-product of this increased
CO2 in our oceans, is that
they are becoming more acidic.
When carbon dioxide goes into
sea water, it reacts with water
molecules to produce an acid.
That's something we
can actually show here.
Sea water around the planet has
a pH of probably 8.1 to 8.2.
Now what I'm going to do is,
I'm going to use the CO2 produced in
my body to blow into the sea water,
and essentially simulate what
would happen if we started to change
the CO2 content of the atmosphere.
So I'm just blowing air from my
body that's got lots of CO2 in it.
And after a while, we'll see the
pH value start to drop, and the lower
this is, the more acid the water is.
There, so it's starting
to drop right now.
The value on the pH meter has dropped
from 8.2 to now 7.9.
Now that happens to be the equivalent
of what would happen to sea water,
if we doubled the concentration of
carbon dioxide in the atmosphere.
Now it's not just the extra acidity
of the sea water that's the problem,
the fact we're blowing carbon dioxide
into this solution also changes
the concentration of a chemical
species known as carbonate.
Carbonate is what
corals need to build their skeletons.
It's to predict how acidification
will affect this ability of corals
to grow their skeletons
that Ove and his team
have built their experiment.
You can see the pH dosing water comes
in here, so that's the low pH water,
and it goes into four points, that
have poles going all the way down.
For the first time anywhere,
they will be subjecting
sections of living reef
to different concentrations of CO2.
What's really neat about this
experiment is you've got corals
growing as naturally as possible,
but under different
atmospheres of CO2.
And you've got to have
replicates, so we've got, ah,
two that at today's setting,
and then two that are really, one
of the worst case scenarios,
where we continue to build up CO2 and
we'll see, you know,
as much as a thousand parts
per million above coral reefs.
Now, from the laboratory, we've
got very good information to say that
that's going to do corals in
but we're trying to do it
here in nature, with these
different conditions,
in these different chambers.
Today, the system goes online.
But first each chamber must be
hooked up to a control module,
whose computers will help maintain
precise water conditions,
24 hours a day.
I see it as a little
bit like a lunar lander.
We're hoping to go for ecologically
relevant lengths of time,
which is hopefully a year
and that's, hopefully we'll get the
seasonal cycles, we'll see,
we might even see bleaching events,
all sorts of interactive phenomenon.
So we're hoping for that,
but that's going to be a challenge,
because no-one's really ever
run an experiment like this,
or for any length of time.
For the scientists,
this moment is the culmination of
many months of hard work.
Only two years of your guy's lives,
we can start again, can't we?
I don't think so.
One, two, three.
Mind the coral.
Just be careful not to fall over,
you're coming to the coral there.
A few hours later and the
underwater lab is up and running.
All our instruments are online, and
as we see the data that each of the
different instruments are giving us,
we can see that we're monitoring
the chemistry in the environment,
so we know what's happening with the
chemistry on the reef flat,
and at the same time it lets us
see how successfully
we're recreating these future CO2
conditions that are predicted
for fifty or a 100 years.
And you can watch the chemistry
change before your eyes,
it's, it's pretty exciting.
But if this experiment does indeed
confirm what many scientists are
predicting,
what does that mean for
places like the Great Barrier Reef?
Already, at the concentration of CO2
we have in the atmosphere, we're
already seeing very large responses
from coral reefs, we're seeing
large scale mortality events,
and scientists are now recording
the decline in the calcification
that's going on in reefs.
And this is not seen in hundreds
and hundreds of years of records.
So if we go forward in time,
we may see reefs degrading
such that, over time, we'll lose
these great wonders of the ocean.
All of which raises the question,
what can be done to save them?
So there's really two
things we've got to do.
The first is, we've got to limit
further increases in CO2,
because we know that those futures
don't have corals in them,
will rapidly exceed
the known conditions for coral reefs.
The second thing
we've got to do is treat
reefs better on a local scale,
we've got to reduce the over fishing,
we've got to reduce the pollution,
the sedimentation and so on.
And if we do that, we will have
coral reefs survive the century.
One of the key responsibilities
of scientists is to really provide
the evidence of what's happening
and put it in a format, so that
people can realise the impacts that
CO2 emissions are going to have,
and convince them that if
they don't do something about
how they live, day to day,
there's going to be
real consequences, for the oceans,
and for the whole planet.
To my mind, acidification is the
greatest threat facing oceans today.
Even if we stopped our
carbon emissions now,
it would be many centuries before
the oceans returned to full health.
But humanity is damaging the ocean
and ocean life in ways which are
very surprising, and which we're
only just beginning to understand.
The dips under here is, is
showing that we've just come down off
the bank, come off the edge of it,
it's getting deeper now.
Stellwagen Bank National Marine
Sanctuary, some 30 nautical miles
off the eastern coast of
the United States.
Very productive area, of course,
at that edge of that bank,
feeding frenzies up there with,
four or five different species
all, all entangled.
Marine biologists
David Wylie and Denise Risch
are scanning the horizon for
signs of one of the largest animals
to live in the ocean.
That's some really nice open
mouth feeding over there,
I can see four or five
animals all working together.
The humpback whale.
These are humpback whales,
they're an endangered species,
one of the real common animals
found in the sanctuary.
Although they're endangered
worldwide, this is really a
hotspot for humpback whales.
This is more open mouth
feeding over here.
For me this is one of the best
feeding aggregations I've ever seen,
I think we are, we're having probably
15 to 20 humpback whales
in the area, all actively feeding.
But despite this being a marine
sanctuary, the humpbacks don't
have these waters to themselves.
And that's because Stellwagen
sits in the middle of one of
America's busiest shipping lanes.
On a yearly basis we've got about
500 different vessels,
and about 4,000 transits
going through the sanctuary.
What you're going to see
here is a day by day plot,
for one month,
of that activity.
So each one of these black lines
you're seeing is the track of a
vessel as it goes in the sanctuary.
You can see those prop marks right
along that tail stuck on the animal?
That's from being hit by,
not one of the big ships that
we've been working with, but
from a smaller, more pleasure craft,
you can see the prop marks running
right up the side of the animal.
So they're also a risk out
here we're trying to deal with.
It's to help avoid these collisions
that David has been working closely
with scientists from the
Census of Marine Life, on a new
method of tracking whales, not on
the surface, but underwater.
The system employs
sophisticated sensors called D Tags,
that are attached to the whales
using suction cups.
Left, left, left, up, down, perfect.
Oh, beautiful.
Oh, perfect, perfect.
After a set time,
the tags detach themselves
and their data is downloaded.
Once we get the tag data back,
we download it into this
programme called Track Plot,
and it was designed specifically
for us to visualise our whale data.
What's been exciting about it
is, for the first time,
it's allowed us to really function
like terrestrial biologists,
where we can watch an animal from the
beginning of a behaviour to the end,
whereas before, all we could watch
was an animal taking breaths at the
surface and disappearing.
By plotting these movements,
the scientists have been able
to identify
those parts of the sanctuary with
the most whale activity,
so enabling them to
redirect shipping, and
reduce the number of collisions.
But this new technology has also
allowed them to monitor another
crucial aspect of whale behaviour.
Travel down into the ocean, and
gradually the light begins to face.
At 200 metres,
almost all the colours of the
light spectrum have been absorbed.
By 1,000, any light
has disappeared completely.
At these depths,
eyes are of little use.
Instead, this is a world of sound.
The world that whales have evolved
to make their own.
Humpback whales are one of the
probably most vocal, marine mammals
and the best well, understood.
WHALE SONG
They use sound kind of, kind of like,
like we use our, you know, vision,
they use it for,
um, to, to navigate,
they use it to find food, they use it
to keep in touch with each other,
and to find mating partners.
So basically, all their basic life
functions are governed by sound.
But in confirming the importance
of sound to whale behaviour,
the scientists have discovered
something else,
that this vital means of
communication is in danger
of being drowned out.
One of the issues that we're trying
to work with at the sanctuary is this
idea of the impact of noise
on the marine environment,
and on large whales in particular.
So you're looking at a bunch
of dots down here,
and those dots actually represent
whales that are calling.
The colour that you're seeing
is really a gradation of
how intense sound is.
So a very bright, like red,
is going to be a very loud sound,
and then if you get down to blue,
that's a much softer sound.
If you can see very nicely
the whales now,
but as a ship goes by you'll see they
disappear into the colouration.
Any time they disappear, that means
that their sound is being masked,
they're not able to send information
from one animal to another.
With noise pollution
doubling every ten years,
David believes this masking
could be having a significant impact
on whale behaviour.
The animals are making
sounds to communicate.
They may be communicating
their presence, the presence
of a food source,
but they're trying to send
information from
one animal to another.
When ships go by, they're unable
to pass that information.
But some scientists think that
ocean noise is affecting whales and
other marine mammals
in an even more fundamental way.
Here at Woods Hole Oceanographic
Institution, eight kilometres
south of Stellwagen,
a group of scientists are carrying
out research into the complex
hearing mechanism of marine mammals.
The work is being led
by Dr Darlene Ketten,
a world expert in not only animal,
but also human hearing.
We have a large body
of knowledge about how humans
lose hearing and exactly how
certain conditions affect hearing.
We're taking that
information now and applying it
directly to whale and dolphin ears.
Like the scientists at Stellwagen,
Darlene also has concerns about the
effect ocean noise is having
on these animals.
For whales and dolphins, it's very
much like our living next to an
airport, with planes going off
24 hours a day, living
next to freeways with
traffic jams constantly,
living in a factory with lots of
pounding machinery going on,
24 hours a day.
This morning she's looking for
physical evidence of how such noise
may have affected the
hearing of this dolphin,
found washed up on a local beach,
a process that begins with a
highly detailed internal scan.
CT scanning is a phenomenal tool,
modern imaging lets us actually
look at something at levels of detail
that you could not do normally,
without dissecting, and slicing down
to thin slices, mounted on slides.
People like Da Vinci would have
loved this, because you get
to see the whole body,
as well as micro parts of it.
That might be a calcified cyst.
Millimetre by millimetre,
the dolphin's medical history
is gradually revealed.
We got some lung collapsing there,
liver disease,
heart's a little enlarged.
OK, let's change
our parameters and focus on the ears.
Switching attention to the
dolphin's internal ear structure,
it's quickly apparent
that all is not as it should be.
What we're looking at here is
the whole head,
at half millimetre slices.
On both sides, there's some loss of
tissue at the inner ear,
especially in the
nerves going to the ears.
Here we can see that there's very
little nerve in this region.
This should be filled with tissue
and there's actually only about 50%
of what we'd expect to see,
which would have
made it very difficult for
this animal to hear normally.
While Darlene accepts that
this type of hearing loss
can have a number of causes,
her experience of not
only scanning marine mammals,
but also dissecting them,
has convinced her that ocean
noise is also playing its part.
We are seeing ears from animals,
particularly in very noisy areas,
like the North Atlantic
and the North Sea, that have hearing
loss clearly related to noise.
It's throughout the entire inner ear,
but equally important, the rest of
the auditory system
also shows some damages that
suggest that they are under stress
from the noise,
which is an important part of
noise effects, not just
hearing loss, but stress.
Taken together,
Darlene believes this combination
of hearing loss and stress
has very serious
implications for marine mammals.
Consider that hearing is a critical
sensory system for these animals,
it's fundamental to
everything that they do.
If we affect their ability to hear,
if we mask noise with other noise
that we're putting in the oceans,
even if we don't damage their
hearing directly, it's going to
impact their ability to survive.
But more concerning is the
possibility that ocean noise might
be affecting a much wider
cross section of marine life.
Hearing is not an important sense for
just whales and dolphins,
but for virtually
any animal in the oceans.
Clearly, if hearing can be affected
in a whale and dolphin,
if their prey also use their ears,
noise could be affecting the prey
and its ability to survive too.
Much more research
is required before we will fully
understand the implications
of ocean noise for marine life.
But as with other human impacts,
like over-fishing and acidification,
it will only be through
the power of evidence that we can
hope to bring about change.
From the cold waters
of the North Atlantic...
..to the coral reefs of the Pacific,
and beyond, the Census of Marine
Life has provided us
with a unique insight
into our oceans,
both past
and present.
A new baseline of knowledge,
from which to make sense of
this most vital of eco-systems.
But the census has also given us a
glimpse of the future, in which many
species and habitats
could end up
disappearing, some before we've even
had the chance to discover them.
This is a map of the world's oceans,
as you've probably
never seen them before.
It represents the impact that
human activities have made on them,
from shipping and fishing, to
pollution and climate change.
The redder the colour,
the greater the degree of impact.
In the seas off Britain, fishing,
pollution, the production of oil
and gas has turned them deep red.
Farther westwards,
the colour becomes orange,
proof that even thousands of miles
away from the continents,
man's activity is still being felt.
In fact, only very few areas of the
ocean's surface remain relatively
unaffected by human activity,
about 4%, like those small patches
of blue around the Torres Straits,
just north of Australia.
What this map will look like
in 50 years' time, or even 10 years'
time, how much redder it will be,
depends on how much notice we
take of facts revealed from projects
like The Census of Marine Life.
Until such time,
the question of whether it
is too late to save the ocean
will hang in the balance.
# Somewhere beyond the sea...#
Things are not going to go back to be
the way they were 200 years ago,
or even 50 to 100 years ago.
But that doesn't mean it's too late.
#..and watch as the ships
That go sailing...#
It's pretty grim,
it's pretty grim, and to think
it's not grim is self deluding.
But I think that we need
to live in hope,
whether it's too late, who knows.
There will be some changes in
the oceans in the future,
but the magnitude of those
changes are somewhat
dependant on what we do now,
because we're
running out of time.
If we don't do something soon,
we'll have really dramatic changes
that could have really important
consequences for the future.
I feel that we're right at the
moment where, if we go any further,
we will not be able to save
the ocean, and that will be
at great cost to ourselves.
But right now, I think we can do a
lot, we can just save this place,
I mean it's the heart and lungs
of the earth, I mean we
can't afford to lose it,
so we're not going to lose it.
# We'll meet, I know we'll meet
Beyond the shore
# We'll kiss just as before
# Happy we'll be, beyond the sea
# And never again
I'll go sailing...#
the world's oceans have held a
special place in our imagination.
Without them,
life would never have come about.
We're only really waking up
to how important the ocean
is for life on this planet.
Today, some four billion years after
they formed, our oceans continue
to dictate life on earth.
Oceans are absolutely critical.
There's billions of people around
the planet who are dependent on the
resources that we get from oceans.
But this most precious of assets
has never been under greater threat.
As the human population
nears seven billion, so our
oceans are struggling to cope.
It's quite clear that humans
have had a profound impact
on this eco-system - we are talking
now about an unnatural ocean.
If we haven't massive changes to the
oceans and, and how they function,
it could have really direct impacts
on humans and their societies.
With time running out,
marine scientists around the world
have been working as never before...
Seventy five in the water,
we're fishing.
..to save this vital eco-system.
We really do risk losing
species before we've even
been introduced to them.
But is it too late?
The living ocean is very fragile,
and don't for a minute believe
that we can't screw it up
much worse than it is today.
Spread over an area of 360 million
square kilometres,
the world's oceans cover
more than 70% of our planet.
So large is their volume,
that almost all of
the earth's available
living space consists of water.
It's one of the great
contradictions of the oceans,
that although they
lie all around us,
they remain the most mysterious
of the earth's eco-systems.
What's living just out there is
hidden from the sight of most of us.
But in recent years, our
understanding of this vast habitat
has begun to increase,
thanks, in part,
to one of the most ambitious,
inspiring, not to say timely,
scientific projects of my lifetime.
Called The Census of Marine Life,
its goal has been to compile the
most comprehensive list, to date,
of life in our oceans,
from the largest of mammals,
to the tiniest of microbes.
There have been few explorations of
the ocean on a par with this census.
Um, the only thing that I can think
of that really is like that, are the,
you know, the great exploratory
voyages of hundreds of years ago.
Involving over 2,000 scientists,
from almost 90 countries,
it's used the latest technology
to explore and document some of
the ocean's most remote regions.
There's never been as big a project
looking at the natural world.
And we census human populations,
we understand about
how many trees grow on the land,
but we have never, ever had
a baseline survey of what
actually lives in the oceans.
Literally the oceans are the support
system for all life on earth.
And if you don't care about the
oceans, then you're basically saying,
I don't care about
what happens to life on earth.
What the census amounts to is a
completely new biography of this,
the largest habitat on earth.
Not only has it increased our
knowledge of WHAT lives there,
but it also enhances
our understanding of how
that life keeps the planet alive.
Today, the health of the oceans
is in danger as never before,
and it could well be
that the census
could prove to be a vital tool
in safeguarding their future.
For the last five years, marine
biologist Dr Julian Caley has
been overseeing a unique project,
whose results have formed
an invaluable part of the census.
The aim of this project?
To catalogue the diversity
of the most complex eco-system
in the ocean - coral reefs.
A task so huge that it has
called for a new and innovative
way of collecting evidence.
This morning, Julian
is heading out to a long,
thin stretch of coral reef,
called Ningaloo
in Western Australia,
to recover some of that evidence.
Coral reefs host more biodiversity
than any other system in the ocean.
People appreciate the diversity
of the rainforest, but we don't
know about the diversity of reefs to
the same extent, and it's because we
haven't had the opportunity
to get out
and actually start
sampling all that biodiversity.
Together with dive buddy
Greg Coleman, Julian will be
descending to a depth of ten metres,
to retrieve a small plastic box
that's been attached to the sea
floor for the past twelve months.
OK, this is what we're
out here today to collect,
this is what we call an ARMS,
it stands for Autonomous
Reef Monitoring Structure.
It's a simple design that we can
replicate, and the purpose of it
is to provide some structure,
that we can take these down, we
can put them on, on the reef, and
things will come and live in them.
A simple, but ingenious design
that has helped Julian and his team
to retrieve countless thousands
of specimens from the sea bed.
After a thorough search of the area,
Julian and Greg eventually find
what they've been looking for,
quickly covering the ARMS
with a second box, to prevent
any creatures inside from escaping.
And with the ARMS safely on board,
the team head back to the lab.
Just a stone's throw from the
shoreline, the low-tech surroundings
of a rundown sheep station
double up as a makeshift laboratory.
We might just need a bit more
water in there. Yeah, we're
going to need some more water.
This one looks like it's got maybe
a bit more life on it than some of
the previous ones we've pulled up.
Here, work gets underway,
dismantling the reef-monitoring
structure.
We want to get everything
out of it, there might be a few
creatures still living in there.
So far, the project has recovered
almost two hundred of these boxes,
each one containing a
cross section of reef life.
As we dismantle these, we could
expect to find anywhere up to
hundreds of different species,
lots of which probably would be
invisible to the naked eye,
but that taxonomists can identify
with a microscope later on.
Ooh, brittle star. We find a
whole range of different life,
from the algae, the crustaceans,
brittle stars, there's obviously
the colonial animals, like
the corals, and the soft corals,
and the bryozoans.
It's a real snapshot
of the biodiversity of the place.
But collecting all this biodiversity
is only the first step.
The next is to identify it.
Every time one of these boxes
come up, or coral rubble samples
come up, it's an adventure.
There are so many different
tiny invertebrates that live
in the cracks and crevices
of algaes and corals.
These animals I work with, these
polychaete worms are very small,
sort of,
one to about ten millimetres.
Within this genus, there's only one
species that has been recorded,
in the 1970s.
I, so far, have found 22 new
species, belonging to this genus.
I focus on the seaweeds
and the algae.
And in algae,
I work with macroalgae
and we go, dive, and snorkel,
and collect everything we find.
So far I think we have 70 species.
We're part of a group with
The Census of Marine Life,
who's looking at marine parasites.
And what we look at are
the parasitic organisms
that live in the internal organs
and tissues of various reef fish.
Just about every day we'll find a new
species. There's a lot of work to do,
many, many lifetimes.
To date, the coral reef project
has identified more than
1,000 likely new species,
a number that rises to an estimated
6,000 across the census as a whole.
The census has really uncovered not
only new species and new life forms,
but just new understanding of
where they live and how they live.
And so it's everything from microbes,
to understanding connections between
small crustaceans, to finding new
species of fish and squids,
that have been quite remarkable,
and it's literally thousands
of new species,
in dozens of new environments.
But as these remarkable discoveries
are enhancing our knowledge
of what lives in the oceans,
and where, time is passing
only too swiftly.
It's one of the ironies
of marine research that,
as we discover more and more about
the oceans and what lives there,
more and more of it is disappearing.
And the reason for that,
of course, is us.
I think all the threats to the
ocean at the moment are man-made.
There's no question that humans
are eco-system engineers now.
Recent studies have found that there
aren't any places left on earth
where humans are not impacting
the ocean environment.
And there is perhaps no single human
activity that poses a more immediate
threat to marine diversity
than commercial fishing.
But with an increasing human
population, more and more dependent
upon the oceans for our food,
how are we to control
how much we take from them?
Here, in the fishing port of
New Bedford, in Massachusetts,
the nature of the problem
soon becomes apparent.
Like many other communities
in this part of the world,
fishing has been a fundamental part
of daily life for hundreds of years.
Do what you can, get us as much
as you can and we'll go from there.
At the local processing plant,
table fish, such as cod and flounder,
are de-scaled, filleted and packed
up for markets throughout the world.
50,000 plus for Monday?
Beautiful, beautiful.
The company has been run
by the Barrie family
for the last hundred years.
Welcome to the Pier Fish Company.
We employ approximately
about 100 people.
My grandfather started the business
in 1910, in the waterfront of Boston.
Snow white, just like my baby's butt
when, when he was born. Beautiful.
Every day, up to 90,000
kilograms of fish pass
through these doors.
A seemingly never-ending
conveyor belt of marine life.
But appearances can be deceptive,
because while stocks
might look plentiful,
companies like Pier Fish
are now having to source that stock
from further and further afield.
What's the update on, um,
the Courageous, as of today?
He's fishing in a barren sea.
Good Chris, good, good, we
appreciate that, we appreciate that.
From a 100% of our
production from domestic markets,
I'd say right now it's about 15%.
The rest is all imported
from out of the country,
or other parts of the country.
These days everything's coming in by
factory trawler, by rail car,
over the road by truck, it comes
from China, it comes from Indonesia,
it comes from Vietnam,
it, it, Russia, it, coming from
all over the world now.
While some of this change can be
attributed to the demand for ever
more exotic species,
it doesn't hide the fact
that fish stocks globally
have been drying up for decades.
And what's brought this about
is technology.
A combination of giant factory
ships, hi-tech sonar and nets
as long as sixty kilometres,
have enabled us to
plunder the seas at will.
Air transit and Styrofoam cooler
boxes have made any kind of living
creature from the sea
available anywhere else in the
world, in 24 hours, and it's
that sort of pressure
that is simply
not sustainable going forward.
Confronted with this technological
onslaught, many species have
reached the point of collapse.
In 2003, researchers from
the Census published a paper
in the science journal Nature,
comparing fish numbers
with those of 1950.
What they concluded was that
in a little over fifty years,
90% of top predators,
such as tuna, shark,
and marlin,
had been fished from the sea.
It's a predictable pattern in a
sense, things that reproduce slowly
are likely to be more vulnerable
if they're under
intense fishing pressure.
And it's a pattern that has
consequences for all ocean life,
owing to the nature of
the marine eco-system itself.
A lot of people would be familiar
with the term "food chain" - it's
one of those things that,
it's very evocative, you know,
the little thing that gets eaten by
the bigger thing,
gets eaten by the even bigger thing.
But in reality, most marine systems
are much more like a food web.
What you end up doing is, if
you take out a whole bunch of the
individuals from a particular level
in that, in that trophic
web, you can affect change
within the rest of the web.
And not necessarily
change for the better.
We can't imagine
that these systems function in
a linear way, they just don't.
And so we don't know, if you push
here, what actually happens there.
We do know that if you
keep catching all the fish, shooting
all the whales and seals,
netting all the birds, and taking
them out of the system, ultimately
you'll be left with copepods
and bacteria and some
other things, that won't make
the picture as pretty.
In one of the most disturbing pieces
of research commissions by the
census, the question was asked,
"How much longer can our oceans
tolerate the present level
of commercial fishing?"
The answer was simple and stark -
if present trends continue,
commercial fishing as we know it
will have collapsed
by the year 2050.
An outcome so catastrophic
that marine scientists have been at
the forefront of efforts
to manage remaining fish stocks,
before some species are
lost for good.
Massachusetts Bay,
in the north west Atlantic.
Hey, you're good to go.
Clear.
Onboard the fishing trawler,
Gloria Michele, the crew are letting
out their first net of the day.
Just another fishing vessel
going about her daily business.
Last 25.
But what sets this boat apart from
the vast majority of other trawlers,
is that she's using a type of net
that has been declared illegal.
Made from a very fine mesh, its
sole purpose is to catch whatever
is out there, regardless of size.
First mate, Carl Rhodes, is hopeful
it will ensure a good haul.
Sometimes we catch big torpedo rays,
and some of the larger animals too,
sculpins, sea robins,
just all kinds of fish that live
closer to the bottom.
At 50 metres down, the
winching mechanism comes to a halt.
75 in the water, we're fishing.
And the wait begins.
On a given signal,
the net is finally hauled in.
But as its contents spill out
onto the deck, it's clear
that this will be no bumper payday.
The last three days, all the
catches have been a little light.
While a catch this small would
normally be a disappointment,
for the Gloria Michele and her crew,
it's not a concern.
Because she isn't out here to turn a
profit. Instead, she's fishing for
an altogether different reason.
Who's got the little whiting bucket?
As part of a scientific survey
of fish stocks in the area.
For scientist Matt Camisa,
it's vital that each trawl
is exactly like the last.
The most important thing we do is we,
we do the same sampling technique,
the same methods, the same gear,
ah, consistently.
Consistency is the key, if you
keep it consistent, you can
look at the trends over time
and know that you haven't
influenced that trend.
Two hours later, the
Gloria Michele is in position
over her next survey site,
and the whole process begins again.
These are winter flounder, a lot
of people fish for these around here.
So what we're going to
do is, now that we have
the weight on all of these,
we're going to take
the lengths on them,
some of them have to be
sampled, we'll cut them open,
determine the sex and maturity.
These are the otoliths, or the ear
bones, they have rings on them, like
rings of a tree,
that's what they use to age them.
Determining the age of each fish
is crucial to the survey,
because only by getting an idea of
juvenile numbers, can the scientists
estimate how plentiful fish
stocks will be in the future.
All of our data, the
State Inshore Trawl survey data
gets fed to the Federal database,
which is used, to do all
these, ah, stock assessments
on all these various species.
And what, after they've done all
these stock assessments,
they make the management regulations
and all the decisions on what
fisherman can and can't do,
when they can catch them, how much
they can take, that's very valuable.
So valuable that some species
have actually begun to bounce back.
Certainly some stocks have rebounded.
We've had a fluke, a good
rebound in our fluke resource,
that's not something we're seeing
here today, but, yellowtail
resource is doing quite well also.
It's a mixed bag, some species have
gone up and others have gone down.
In fact, it's been estimated that
in American waters, where management
strategies have been implemented,
almost 50% of fish stocks have
shown some sort of increase.
But while this might be grounds for
hope, it raises another question,
which is exactly how productive
should we expect our oceans to be?
A question to which the answer
lies back in time.
Professor Jeff Bolster has been
part of a census-led project
documenting the history of
commercial fishing in New England.
Caught 4,760. Caught 1,600.
Caught 2,300 fish.
Caught 1,000 fish.
Caught 5,500 fish.
Caught 3,000, 24,000, 70,000
80,000, 100...
It's impossible to imagine the
coast of New England without
imagining commercial fishing,
This is the
oldest profession in America,
and it's one that
is threatened today,
but is woven into
these communities,
in a way that is deeply, deeply
part of their essence.
By trawling through
the historical record,
Jeff has become convinced that the
key to the future productivity
of the oceans lies in the past.
Every European that came here
wrote with astonishment about
the nature of the eco-system.
And the point is that they weren't
comparing it to the Caribbean, or,
or the exotic East Indies,
where all the fish were different,
they were comparing it to
their own back yard,
it was salmon and herring and skate,
everything they were familiar
with, but the numbers were colossal.
Just how colossal
is apparent from even the most
cursory examination of the record.
Monday, 4th day of July, 1859.
This day begins with light
winds and calm, and continues
throughout the day.
Thus ends the glorious 4th,
by all hands toiling hard in fishing,
and caught 2,700 codfish.
This is the log of the Schooner
Mahalia from Newburyport,
just down the road.
They're catching cod, the numbers
are phenomenal,
they've come in to spawn, and then
once the spawning is done, these
men are catching them.
The daily catch is
here for each man,
I mean we have one man caught
472 fish, another man 461,
403, 410, 390,
So, again, this is a
significant number of fish.
Using these historical figures,
Jeff has been able to compare
past cod numbers with present.
The annual catches today in the
entire gulf of Maine are
about 4,000 metric tonnes,
if you exclude the
recreational catch.
But, in 1861, 70,000 tonnes,
hand lining, little sail boats,
today 4,000 tonnes,
big modern steel ships, electronic
fish finders, navigation system.
So the system has
changed profoundly.
By showing the marine eco-system
as it once was, Jeff hopes to change
perceptions of what constitutes
a healthy fish population today.
I mean if you imagine, sort of the
pathetic graph of fish landings,
is that goes
down, down, down, down, down.
And around 1990, around
here, it bottoms out,
and now there's an uptick,
OK, there's an uptick and it's good.
And what people sometimes say is
well, look, there's more fish now
than there used to be,
because they're talking about now
compared to 20 years ago, right?
But they need to think about the
scale, the uptick is tiny, and what
we've had is this huge descent.
And what our group is doing, by
providing that historical
perspective,
is saying we need to look at
this eco-system through time.
But setting targets based on the
number of fish that used
to live in the oceans,
doesn't mean that we can
just expect to turn back the clock.
We don't know if it can be
as good again as it once was,
we don't even know if it can be as
good again 100 years out,
as it was 100 years back.
But to not try,
I think, is really short sighted.
We don't want to think about, you
know, matters in the environment
as if we're going to go back to some
pristine state, or even go back to,
you know, the
conditions 100 years ago.
Um, you know, eco-systems change,
human activities change, and so on.
But that doesn't mean that we
should ignore at least the potential
for oceans to produce, um,
you know, a greater
abundance of fish.
Whether or not the oceans
can ever again be as productive
as they once were,
is a question that
scientists can't yet answer.
But they are sure of one thing -
if we are to save the commercially
important species of fish
that are currently under threat
of extinction, we must act
with the data we now have.
Do nothing,
and the implications are inevitable,
the loss of dozens of species
of marine fish round the world.
But on the other side of the world,
there are habitats that
are facing a threat,
the implications of which
scientists are only just
beginning to work out.
At the southern tip of Australia's
Great Barrier Reef, lies the
tiny coral quay of Heron Island.
A designated national park,
its crystal clear waters have
been attracting tourists
for almost 80 years.
But these waters also contain clues,
which suggest that by the time
another 80 years is up,
they will have changed
beyond all recognition.
Well, it looks like
it has survived the night.
Today, Professor Ove Hoegh-Guldberg
from the University of Queensland,
is launching a unique experiment
to monitor how this change
will affect coral reefs.
In 2006, Ove took part
in a BBC documentary,
following the effects of
global warning on the reef.
When I come here and see this,
this really stressed-out reef,
I find myself getting
really concerned.
It's another reminder that
there are huge changes on
the way with climate change.
Everywhere I look,
all I can see is bleached corals,
corals that are normally brown,
are now glowing a brilliant white.
This is because of the
algae having left the tissues,
all that's left are the
absolutely reflective skeletons.
Four years ago we were looking at
the impacts of
temperature on coral reefs,
and that's where we've had rising
ocean temperatures
and mass coral bleaching that's
threatening the entire eco-system.
But since that time,
there's now the realisation that
there are even larger forces at play,
and that these forces are combining
with things like temperature,
to make a very gloomy
future for coral reefs.
The cause of this new
concern is an environmental
impact with the potential
to be every bit as disastrous for
reefs as rising sea temperatures...
ocean acidification.
For billions of years,
the oceans have played a vital role
in keeping the earth's
carbon dioxide levels in check.
The ocean's involved in a huge
conveyor belt of sort of a chemical
reactor, if you like,
in which CO2 goes into the ocean,
it's fixed by plants, it may
be deposited as calcium carbonate,
and through these
very, very large scale circulations
of water on our planet, it's
essentially processing the atmosphere
and keeping our planet habitable.
And of course, we're only
just starting to realise that this is
actually what we live off,
it's the ocean.
But since 1960,
carbon dioxide levels in the
atmosphere have risen by almost 20%,
and by roughly 30% since the start
of industrialisation.
Like all things,
oceans have a capacity.
So as we've been pumping CO2
into the atmosphere by the
burning of fossil fuels,
we've actually started to exceed
the capacity of the ocean to
absorb that carbon dioxide.
One by-product of this increased
CO2 in our oceans, is that
they are becoming more acidic.
When carbon dioxide goes into
sea water, it reacts with water
molecules to produce an acid.
That's something we
can actually show here.
Sea water around the planet has
a pH of probably 8.1 to 8.2.
Now what I'm going to do is,
I'm going to use the CO2 produced in
my body to blow into the sea water,
and essentially simulate what
would happen if we started to change
the CO2 content of the atmosphere.
So I'm just blowing air from my
body that's got lots of CO2 in it.
And after a while, we'll see the
pH value start to drop, and the lower
this is, the more acid the water is.
There, so it's starting
to drop right now.
The value on the pH meter has dropped
from 8.2 to now 7.9.
Now that happens to be the equivalent
of what would happen to sea water,
if we doubled the concentration of
carbon dioxide in the atmosphere.
Now it's not just the extra acidity
of the sea water that's the problem,
the fact we're blowing carbon dioxide
into this solution also changes
the concentration of a chemical
species known as carbonate.
Carbonate is what
corals need to build their skeletons.
It's to predict how acidification
will affect this ability of corals
to grow their skeletons
that Ove and his team
have built their experiment.
You can see the pH dosing water comes
in here, so that's the low pH water,
and it goes into four points, that
have poles going all the way down.
For the first time anywhere,
they will be subjecting
sections of living reef
to different concentrations of CO2.
What's really neat about this
experiment is you've got corals
growing as naturally as possible,
but under different
atmospheres of CO2.
And you've got to have
replicates, so we've got, ah,
two that at today's setting,
and then two that are really, one
of the worst case scenarios,
where we continue to build up CO2 and
we'll see, you know,
as much as a thousand parts
per million above coral reefs.
Now, from the laboratory, we've
got very good information to say that
that's going to do corals in
but we're trying to do it
here in nature, with these
different conditions,
in these different chambers.
Today, the system goes online.
But first each chamber must be
hooked up to a control module,
whose computers will help maintain
precise water conditions,
24 hours a day.
I see it as a little
bit like a lunar lander.
We're hoping to go for ecologically
relevant lengths of time,
which is hopefully a year
and that's, hopefully we'll get the
seasonal cycles, we'll see,
we might even see bleaching events,
all sorts of interactive phenomenon.
So we're hoping for that,
but that's going to be a challenge,
because no-one's really ever
run an experiment like this,
or for any length of time.
For the scientists,
this moment is the culmination of
many months of hard work.
Only two years of your guy's lives,
we can start again, can't we?
I don't think so.
One, two, three.
Mind the coral.
Just be careful not to fall over,
you're coming to the coral there.
A few hours later and the
underwater lab is up and running.
All our instruments are online, and
as we see the data that each of the
different instruments are giving us,
we can see that we're monitoring
the chemistry in the environment,
so we know what's happening with the
chemistry on the reef flat,
and at the same time it lets us
see how successfully
we're recreating these future CO2
conditions that are predicted
for fifty or a 100 years.
And you can watch the chemistry
change before your eyes,
it's, it's pretty exciting.
But if this experiment does indeed
confirm what many scientists are
predicting,
what does that mean for
places like the Great Barrier Reef?
Already, at the concentration of CO2
we have in the atmosphere, we're
already seeing very large responses
from coral reefs, we're seeing
large scale mortality events,
and scientists are now recording
the decline in the calcification
that's going on in reefs.
And this is not seen in hundreds
and hundreds of years of records.
So if we go forward in time,
we may see reefs degrading
such that, over time, we'll lose
these great wonders of the ocean.
All of which raises the question,
what can be done to save them?
So there's really two
things we've got to do.
The first is, we've got to limit
further increases in CO2,
because we know that those futures
don't have corals in them,
will rapidly exceed
the known conditions for coral reefs.
The second thing
we've got to do is treat
reefs better on a local scale,
we've got to reduce the over fishing,
we've got to reduce the pollution,
the sedimentation and so on.
And if we do that, we will have
coral reefs survive the century.
One of the key responsibilities
of scientists is to really provide
the evidence of what's happening
and put it in a format, so that
people can realise the impacts that
CO2 emissions are going to have,
and convince them that if
they don't do something about
how they live, day to day,
there's going to be
real consequences, for the oceans,
and for the whole planet.
To my mind, acidification is the
greatest threat facing oceans today.
Even if we stopped our
carbon emissions now,
it would be many centuries before
the oceans returned to full health.
But humanity is damaging the ocean
and ocean life in ways which are
very surprising, and which we're
only just beginning to understand.
The dips under here is, is
showing that we've just come down off
the bank, come off the edge of it,
it's getting deeper now.
Stellwagen Bank National Marine
Sanctuary, some 30 nautical miles
off the eastern coast of
the United States.
Very productive area, of course,
at that edge of that bank,
feeding frenzies up there with,
four or five different species
all, all entangled.
Marine biologists
David Wylie and Denise Risch
are scanning the horizon for
signs of one of the largest animals
to live in the ocean.
That's some really nice open
mouth feeding over there,
I can see four or five
animals all working together.
The humpback whale.
These are humpback whales,
they're an endangered species,
one of the real common animals
found in the sanctuary.
Although they're endangered
worldwide, this is really a
hotspot for humpback whales.
This is more open mouth
feeding over here.
For me this is one of the best
feeding aggregations I've ever seen,
I think we are, we're having probably
15 to 20 humpback whales
in the area, all actively feeding.
But despite this being a marine
sanctuary, the humpbacks don't
have these waters to themselves.
And that's because Stellwagen
sits in the middle of one of
America's busiest shipping lanes.
On a yearly basis we've got about
500 different vessels,
and about 4,000 transits
going through the sanctuary.
What you're going to see
here is a day by day plot,
for one month,
of that activity.
So each one of these black lines
you're seeing is the track of a
vessel as it goes in the sanctuary.
You can see those prop marks right
along that tail stuck on the animal?
That's from being hit by,
not one of the big ships that
we've been working with, but
from a smaller, more pleasure craft,
you can see the prop marks running
right up the side of the animal.
So they're also a risk out
here we're trying to deal with.
It's to help avoid these collisions
that David has been working closely
with scientists from the
Census of Marine Life, on a new
method of tracking whales, not on
the surface, but underwater.
The system employs
sophisticated sensors called D Tags,
that are attached to the whales
using suction cups.
Left, left, left, up, down, perfect.
Oh, beautiful.
Oh, perfect, perfect.
After a set time,
the tags detach themselves
and their data is downloaded.
Once we get the tag data back,
we download it into this
programme called Track Plot,
and it was designed specifically
for us to visualise our whale data.
What's been exciting about it
is, for the first time,
it's allowed us to really function
like terrestrial biologists,
where we can watch an animal from the
beginning of a behaviour to the end,
whereas before, all we could watch
was an animal taking breaths at the
surface and disappearing.
By plotting these movements,
the scientists have been able
to identify
those parts of the sanctuary with
the most whale activity,
so enabling them to
redirect shipping, and
reduce the number of collisions.
But this new technology has also
allowed them to monitor another
crucial aspect of whale behaviour.
Travel down into the ocean, and
gradually the light begins to face.
At 200 metres,
almost all the colours of the
light spectrum have been absorbed.
By 1,000, any light
has disappeared completely.
At these depths,
eyes are of little use.
Instead, this is a world of sound.
The world that whales have evolved
to make their own.
Humpback whales are one of the
probably most vocal, marine mammals
and the best well, understood.
WHALE SONG
They use sound kind of, kind of like,
like we use our, you know, vision,
they use it for,
um, to, to navigate,
they use it to find food, they use it
to keep in touch with each other,
and to find mating partners.
So basically, all their basic life
functions are governed by sound.
But in confirming the importance
of sound to whale behaviour,
the scientists have discovered
something else,
that this vital means of
communication is in danger
of being drowned out.
One of the issues that we're trying
to work with at the sanctuary is this
idea of the impact of noise
on the marine environment,
and on large whales in particular.
So you're looking at a bunch
of dots down here,
and those dots actually represent
whales that are calling.
The colour that you're seeing
is really a gradation of
how intense sound is.
So a very bright, like red,
is going to be a very loud sound,
and then if you get down to blue,
that's a much softer sound.
If you can see very nicely
the whales now,
but as a ship goes by you'll see they
disappear into the colouration.
Any time they disappear, that means
that their sound is being masked,
they're not able to send information
from one animal to another.
With noise pollution
doubling every ten years,
David believes this masking
could be having a significant impact
on whale behaviour.
The animals are making
sounds to communicate.
They may be communicating
their presence, the presence
of a food source,
but they're trying to send
information from
one animal to another.
When ships go by, they're unable
to pass that information.
But some scientists think that
ocean noise is affecting whales and
other marine mammals
in an even more fundamental way.
Here at Woods Hole Oceanographic
Institution, eight kilometres
south of Stellwagen,
a group of scientists are carrying
out research into the complex
hearing mechanism of marine mammals.
The work is being led
by Dr Darlene Ketten,
a world expert in not only animal,
but also human hearing.
We have a large body
of knowledge about how humans
lose hearing and exactly how
certain conditions affect hearing.
We're taking that
information now and applying it
directly to whale and dolphin ears.
Like the scientists at Stellwagen,
Darlene also has concerns about the
effect ocean noise is having
on these animals.
For whales and dolphins, it's very
much like our living next to an
airport, with planes going off
24 hours a day, living
next to freeways with
traffic jams constantly,
living in a factory with lots of
pounding machinery going on,
24 hours a day.
This morning she's looking for
physical evidence of how such noise
may have affected the
hearing of this dolphin,
found washed up on a local beach,
a process that begins with a
highly detailed internal scan.
CT scanning is a phenomenal tool,
modern imaging lets us actually
look at something at levels of detail
that you could not do normally,
without dissecting, and slicing down
to thin slices, mounted on slides.
People like Da Vinci would have
loved this, because you get
to see the whole body,
as well as micro parts of it.
That might be a calcified cyst.
Millimetre by millimetre,
the dolphin's medical history
is gradually revealed.
We got some lung collapsing there,
liver disease,
heart's a little enlarged.
OK, let's change
our parameters and focus on the ears.
Switching attention to the
dolphin's internal ear structure,
it's quickly apparent
that all is not as it should be.
What we're looking at here is
the whole head,
at half millimetre slices.
On both sides, there's some loss of
tissue at the inner ear,
especially in the
nerves going to the ears.
Here we can see that there's very
little nerve in this region.
This should be filled with tissue
and there's actually only about 50%
of what we'd expect to see,
which would have
made it very difficult for
this animal to hear normally.
While Darlene accepts that
this type of hearing loss
can have a number of causes,
her experience of not
only scanning marine mammals,
but also dissecting them,
has convinced her that ocean
noise is also playing its part.
We are seeing ears from animals,
particularly in very noisy areas,
like the North Atlantic
and the North Sea, that have hearing
loss clearly related to noise.
It's throughout the entire inner ear,
but equally important, the rest of
the auditory system
also shows some damages that
suggest that they are under stress
from the noise,
which is an important part of
noise effects, not just
hearing loss, but stress.
Taken together,
Darlene believes this combination
of hearing loss and stress
has very serious
implications for marine mammals.
Consider that hearing is a critical
sensory system for these animals,
it's fundamental to
everything that they do.
If we affect their ability to hear,
if we mask noise with other noise
that we're putting in the oceans,
even if we don't damage their
hearing directly, it's going to
impact their ability to survive.
But more concerning is the
possibility that ocean noise might
be affecting a much wider
cross section of marine life.
Hearing is not an important sense for
just whales and dolphins,
but for virtually
any animal in the oceans.
Clearly, if hearing can be affected
in a whale and dolphin,
if their prey also use their ears,
noise could be affecting the prey
and its ability to survive too.
Much more research
is required before we will fully
understand the implications
of ocean noise for marine life.
But as with other human impacts,
like over-fishing and acidification,
it will only be through
the power of evidence that we can
hope to bring about change.
From the cold waters
of the North Atlantic...
..to the coral reefs of the Pacific,
and beyond, the Census of Marine
Life has provided us
with a unique insight
into our oceans,
both past
and present.
A new baseline of knowledge,
from which to make sense of
this most vital of eco-systems.
But the census has also given us a
glimpse of the future, in which many
species and habitats
could end up
disappearing, some before we've even
had the chance to discover them.
This is a map of the world's oceans,
as you've probably
never seen them before.
It represents the impact that
human activities have made on them,
from shipping and fishing, to
pollution and climate change.
The redder the colour,
the greater the degree of impact.
In the seas off Britain, fishing,
pollution, the production of oil
and gas has turned them deep red.
Farther westwards,
the colour becomes orange,
proof that even thousands of miles
away from the continents,
man's activity is still being felt.
In fact, only very few areas of the
ocean's surface remain relatively
unaffected by human activity,
about 4%, like those small patches
of blue around the Torres Straits,
just north of Australia.
What this map will look like
in 50 years' time, or even 10 years'
time, how much redder it will be,
depends on how much notice we
take of facts revealed from projects
like The Census of Marine Life.
Until such time,
the question of whether it
is too late to save the ocean
will hang in the balance.
# Somewhere beyond the sea...#
Things are not going to go back to be
the way they were 200 years ago,
or even 50 to 100 years ago.
But that doesn't mean it's too late.
#..and watch as the ships
That go sailing...#
It's pretty grim,
it's pretty grim, and to think
it's not grim is self deluding.
But I think that we need
to live in hope,
whether it's too late, who knows.
There will be some changes in
the oceans in the future,
but the magnitude of those
changes are somewhat
dependant on what we do now,
because we're
running out of time.
If we don't do something soon,
we'll have really dramatic changes
that could have really important
consequences for the future.
I feel that we're right at the
moment where, if we go any further,
we will not be able to save
the ocean, and that will be
at great cost to ourselves.
But right now, I think we can do a
lot, we can just save this place,
I mean it's the heart and lungs
of the earth, I mean we
can't afford to lose it,
so we're not going to lose it.
# We'll meet, I know we'll meet
Beyond the shore
# We'll kiss just as before
# Happy we'll be, beyond the sea
# And never again
I'll go sailing...#