The dangers of a noisy ocean -- and how we can quiet it down

This is the sound of orcas
off the coast of Vancouver.

(Whale sounds)

They make these fantastic sounds
not just to communicate,

but also sometimes to echolocate,

to find their way around and to find food.

But that can be tricky sometimes,

because, well, here is the sound
of a ship passing by,

recorded underwater.

(Oscillating sound)

You know, when we think
about marine pollution,

I think we usually think about plastics.

Maybe toxic chemicals,

or even ocean acidification
from climate change.

As a science journalist who often writes
about environmental issues,

those are the things
that have passed my desk

over the past 10 years or so.

But as I recently realized

when I was writing a feature
for the science journal "Nature,"

noise is another
important kind of pollution.

One that often gets ignored.

You know, maybe you've heard
of the dark-skies movement,

which aimed to raise awareness
of the issue of light pollution

and create pockets of unilluminated night,

so that people and animals

could enjoy more natural cycles
of light and dark, night and day.

Well, in much the same way,

there are people now raising awareness

of the issue of noise pollution

and trying to create
pockets of quiet in the ocean,

so that marine life can enjoy
a more natural soundscape.

This is important.

Noise isn't just an irritation.

It can cause chronic stress,

or even physical injury.

It can affect marine life's ability
to find food and mates

and to listen out for predators and more.

Think of all the sounds
we inject into the ocean.

Perhaps one of the most dramatic
is the seismic surveys

used to look for oil and gas.

Air guns produce loud blasts,

sometimes every 10 to 15 seconds,

for months on end.

And they use the reflections
of these sounds

to map the ground beneath.

It can sound like this.

(Explosion sounds)

Then, there's the sound
of the actual drilling for oil and gas,

the construction of things
like offshore wind farms,

sonar

and of course, the nearly constant drone
from more than 50,000 ships

in the global merchant fleet.

Now the natural ocean itself
isn't exactly quiet.

If you put your head under the water,

you can hear cracking ice, wind, rain,

singing whales, grunting fish,

even snapping shrimp.

Altogether, that can create a soundscape

of maybe 50 to 100 decibels,

depending on where and when you are.

But mankind's addition to that
has been dramatic.

It's estimated that shipping has added
three decibels of noise to the ocean

every 10 years in recent decades.

That might not sound like a lot,

but decibels are on a logarithmic scale,

like the Richter scale for earthquakes.

So a small number can actually
represent a large change.

Three decibels means a doubling
of noise intensity in the ocean.

A doubling.

And that's only an estimate,

because no one is actually keeping track
of how noisy the ocean is

all around the world.

There is a body called
the International Quiet Ocean Experiment,

and one of their missions

is to try and plug the hole in that data.

So for example, last year,

they managed to convince
the Global Ocean Observation System

to start including noise

as one of their essential
variables for monitoring,

alongside things
like temperature and salinity.

We do know some things.

We know that sonar can be as loud,
or nearly as loud,

as an underwater volcano.

A supertanker can be as loud
as the call of a blue whale.

The noises we add to the ocean
come in all different frequencies

and can travel great distances.

Seismic surveys off the East Coast
of the United States

can be heard in the middle
of the Atlantic.

In the 1960s, they did an experiment

where they set off a loud noise
off the coast of Perth, Australia,

and they detected it
as far away as Bermuda,

20,000 kilometers away.

So what does all this
sound like to marine life,

what do they hear?

It's kind of difficult to describe.

Sound travels further, faster in water
than it does in air,

and it also packs a different punch.

So sound of the same pressure
will have a different intensity

whether you measure it
in the air or underwater.

Then there's the fact that whales
don't have ears exactly like human ears.

Creatures like zooplankton

don't even have what you would
consider to be ears.

So what does this mean,

what is the impact
on all this marine life?

Perhaps the easiest thing
for scientists to assess

is the effect of acute noise,

really loud sudden blasts

that might cause physical injury
or hearing loss.

Beaked whales, for example,
can go into panicked dives

when exposed to loud noises,

which may even give them
a condition similar to the bends.

In the 1960s, after the introduction
of more powerful sonar technologies,

the number of incidents of mass
whale strandings of beaked whales

went up dramatically.

And it's not just marine mammals,

fish, if they stray too close
to the source of a loud sound,

their fish bladders may actually explode.

The airgun blasts from seismic surveys

can mow down a swath of zooplankton,

the tiny creatures near the base
of the food chain,

or can deform scallop larvae
while they're developing.

Well, what about chronic noise,

the more pervasive issue
of raising background noise

from things like shipping?

That can mask or drown out
the natural soundscape.

Some whales have responded to this
by literally changing their tune,

a little bit like people
shouting to be heard in a noisy nightclub.

And some fish will spend more time
patrolling their borders

and less time caring for their young,

as if they're on high alert.

Chronic noise can affect
people too, of course.

Studies have shown
that people living near busy airports

or really busy highways

may have elevated levels
of cardiovascular disease.

And students living
under busy flight paths

may do worse on some educational tests.

And even while I was
researching this subject,

they were actually blasting out
about three meters of solid granite

from the lot across from my home office

to make room for a new house,

and the constant jittering
of the rock hammer

was driving me completely insane.

And whenever the workers
stopped for a moment,

I could feel my shoulders relax.

This effect has been seen in whales too.

After the terrorist attacks of 9/11,

international shipping largely
ground to a halt for a little while

in the waters off the East Coast
of the United States.

And in that lull,

researchers noticed that endangered
right whales in that region

had fewer chemical markers of stress
in their feces samples.

As one researcher I spoke to likes to say,

"We were stressed,
but the whales weren't."

Now you have to remember,

we have evolved to be a visual species.

We really rely on our eyes.

But marine life relies on sound

the way that we rely on sight.

For them, a noisy ocean

may be as befuddling and even dangerous

as a dense fog is for us.

And maybe sometimes that just means
being a little more stressed,

maybe sometimes it means
spending a little less time with the kids.

Maybe some species can adapt.

But some researchers worry
that for endangered species

already on the brink

noise may be enough
to push them over the edge.

So take, for example,
the southern resident killer whales

that live in the waters
off my home town of Vancouver.

There are only 75, maybe 76 animals left

in this population.

And they're facing a lot of challenges.

There are chemical pollutants
in these waters

and they are running low on the salmon
that they really rely on for food.

And then there's noise.

When researchers studied these
and similar killer whales,

they found that they spend
between 18 and 25 percent less time

feeding in the presence
of loud boat noise.

And that's a lot for a species
that's already struggling

to find enough food to thrive.

The good news, as I heard
from all the researches I spoke to,

is that you can do something
relatively easily about ocean noise.

Unlike the wicked problems
of climate change

and ocean acidification,

you can just dial down
the knob on ocean noise

and see almost immediate impacts.

So for example, in 2017,

the Vancouver Fraser Port Authority

started asking ships to simply slow down

when going through the Haro Strait,

where the southern resident killer whales
are feeding in late summer.

Slower ships are quieter ships.

And because it's Canada, you can just ask,

it can be voluntary.

(Laughter)

(Applause)

In that 2017 trial,
most of the ships complied,

adding about half an hour
to their travel time,

and reducing noise by about 1.2 decibels

or 24 percent of noise intensity.

This year, they decided
to extend the length of time

and the area over which
they're asking ships to slow down.

So hopefully, that has
a positive impact for these whales.

In 2017, the Vancouver
Fraser Port Authority

also introduced discounts in docking fees

for ships that are physically
designed to be quieter.

You know, weirdly, a lot of the noise
from a ship like this

comes from the popping of tiny bubbles
off the back of its propeller.

And you can simply design a ship
to do less of that

and to be quieter.

The International Maritime Organization
has published a huge list of ways

that boats can be made quieter.

And they also have a target

of reducing carbon dioxide emissions
from global shipping

by 50 percent by 2050.

And the great news is that
these two things go hand in hand.

On the whole, a more
efficient ship is a quieter ship.

People have also invented quieter ways
of hammering in the giant posts

needed for giant
wind turbines like this one.

And gentler ways of doing seismic surveys.

And there are some incentives
for using quieter technologies.

The European Union, for example,

has a healthy marine system
directive for 2020.

And one of the ways that they define
a healthy marine system

is by how much noise
is going in those waters.

But on the whole, most waters
remain completely unregulated

when it comes to ocean noise.

But again, most of
the scientists I spoke to

said that there's real momentum
right now in policy circles

to pay attention to this issue

and maybe do something about this issue.

We already know enough to say
that quieter seas are healthier seas.

But now scientists are really scrambling
to come up with the details.

Just how quiet do we need to be?

And where are the best places
to make quiet or preserve quiet?

And how best can we hush our noise?

And you know, I'm not trying to tell you

that noise is the biggest
environmental problem on the planet

or even in the ocean.

But the point is that humankind
has a lot of impacts

on our environmental system.

And these impacts don't act in isolation.

They act together and they multiply.

So even for the ones
that are not so obvious,

we really need to pay attention to them.

I'll tell you about one last experiment,

just because it's so beautiful.

So Rob Williams,

one of the researchers who works
on southern resident killer whales,

also does some work in Bali.

And there, they celebrate
a Hindu tradition

called nyepi, or a day of silence.

And this day, apparently,
is very strictly observed.

No planes take off from the airport,

no boats go out fishing,

the tourists are gently led off the beach
back into their hotel rooms.

And Rob Williams put some
hydrophones in the water there

to see what the impact was,

and it was dramatic.

Sound levels dropped
by six to nine decibels,

about the same
as in the waters after 9/11.

For an "acoustic prospector"
like Williams,

which is what he calls himself,

this silence is golden.

Now he and other researchers
can go back to this place

and see what the fish choose to do

with all this additional
acoustic real estate.

(Sounds of underwater)

I like to think of them
having their own holiday,

feasting and finding mates.

Celebrating their own spot of calm

in an otherwise noisy world.

Thank you.

(Applause)