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This is the sound of orcas
off the coast of Vancouver.
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(Whale sounds)
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They make these fantastic sounds
not just to communicate,
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but also sometimes to echolocate,
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to find their way around and to find food.
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But that can be tricky sometimes,
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because, well, here is the sound
of a ship passing by,
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recorded underwater.
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(Sound)
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You know, when we think
about marine pollution,
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I think we usually think about plastics.
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Maybe toxic chemicals,
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or even ocean acidification
from climate change.
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As a science journalist who often writes
about environmental issues,
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those are the things
that have passed my desk
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over the past 10 years or so.
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But as I recently realized
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when I was writing a feature
for the science journal Nature,
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noise is another
important kind of pollution.
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One that often gets ignored.
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You know, maybe you've heard
of the dark-skies movement,
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which aim to raise awareness
of the issue of light pollution,
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and create pockets of unilluminated night
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so that people and animals
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could enjoy more natural cycles
of light and dark, night and day.
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Well, in much the same way,
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there are people now raising awareness
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of the issue of noise pollution,
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and trying to create pockets
of quiet in the ocean,
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so that marine life can enjoy
a more natural sound scape.
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This is important.
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Noise isn't just an irritation.
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It can cause chronic stress,
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or even physical injury.
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It can affect marine life's ability
to find food and mates
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and to listen out for predators and more.
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Think of all the sounds
we inject into the ocean.
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Perhaps one of the most dramatic
is the seismic surveys,
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used to look for oil and gas.
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Air guns produce loud blasts,
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sometimes every 10 to 15 seconds,
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for months on end.
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And they use the reflections
of these sounds
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to map the ground beneath.
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It can sound like this.
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(Explosion sounds)
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Then, there's the sound
of the actual drilling for oil and gas,
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the construction of things
like offshore wind farms,
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sonar,
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and of course, the nearly constant drone
from more than 50,000 ships
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in the global merchant fleet.
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Now the natural ocean itself
isn't exactly quiet.
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If you put your head under the water,
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you can hear cracking ice, wind, rain,
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singing whales, grunting fish,
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even snapping shrimp.
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Altogether, that can create a sound scape
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of maybe 50 to 100 decibels,
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depending on where and when you are.
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But mankind's addition to that
has been dramatic.
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It's estimated that shipping has added
three decibels of noise to the ocean
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every 10 years in recent decades.
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That might not sound like a lot,
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but decibels are on a logarithmic scale,
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like the Richter scale for earthquakes.
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So a small number can actually
represent a large change.
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Three decibels means a doubling
of noise intensity in the ocean.
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A doubling.
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And that's only an estimate,
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because no one is actually keeping track
of how noisy the ocean is
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all around the world.
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There is a body called the International
Quiet Ocean Experiment,
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and one of their missions
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is to try and plug the hole in that data.
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So for example, last year,
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they managed to convince the Global
Ocean Observation System
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to start including noise
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as one of their essential
variables for monitoring,
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alongside things
like temperature and salinity.
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We do know some things.
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We know that sonar can be as loud,
or nearly as loud,
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as an underwater volcano.
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A supertanker can be as loud
as the call of a blue whale.
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The noises we add to the ocean
come in all different frequencies
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and can travel great distances.
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Seismic surveys off the East Coast
of the United States
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can be heard in the middle
of the Atlantic.
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In the 1960s, they did an experiment
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where they set off a loud noise
off the coast of Perth, Australia,
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and they detected it
as far away as Bermuda,
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20,000 kilometers away.
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So what does all this
sound like to marine life,
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what do they hear?
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It's kind of difficult to describe.
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Sound travels further, faster in water
than it does in air,
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and it also packs a different punch.
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So sound of the same pressure
will have a different intensity
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whether you measure it
in the air or underwater.
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Then there's the fact that whales
don't have ears exactly like human ears.
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Creatures like zooplankton
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don't even have what you would
consider to be ears.
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So what does this mean,
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what is the impact
on all this marine life?
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Perhaps the easiest thing
for scientists to assess
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is the effect of acute noise,
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really loud sudden blasts
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that might cause physical injury
or hearing loss.
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Beaked whales, for example,
can go into panicked dives
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when exposed to loud noises,
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which may even give them
a condition similar to the bends.
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In the 1960s, after the introduction
of more powerful sonar technologies,
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the number of incidents of mass
whale strandings of beaked whales
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went up dramatically.
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And it's not just marine mammals,
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fish, if they stray too close
to the source of a loud sound,
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their fish bladders may actually explode.
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The airgun blasts from seismic surveys
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can mow down a swath of zooplankton,
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the tiny creatures near the base
of the food chain.
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Or can deform scallop larvae
while they're developing.
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Well, what about chronic noise
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the more pervasive issue
of raising background noise
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from things like shipping?
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That can mask or drown out
the natural sound scape.
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Some whales have responded to this
by literally changing their tune,
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a little bit like people,
shouting to be heard in a noisy nightclub.
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And some fish will spend more time
patrolling their borders
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and less time caring for their young,
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as if they're on high alert.
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Chronic noise can affect
people too, of course.
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Studies have shown that people
living near busy airports
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or really busy highways
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may have elevated levels
of cardiovascular disease.
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And students living
under busy flight paths
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may do worse on some educational tests.
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And even while I was
researching this subject,
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they were actually blasting out
about three meters of solid granite
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from the lot across from my home office
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to make room for a new house,
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and the constant jittering
of the rock hammer
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was driving me completely insane.
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And whenever the workers
stopped for a moment,
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I could feel my shoulders relax.
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This effect has been seen in whales too.
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After the terrorist attacks of 9/11,
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international shipping largely
ground to a halt for a little while
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in the waters off the East Coast
of the United States.
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And in that lull,
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researchers noticed that endangered
right whales in that region
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had fewer chemical markers of stress
in their feces samples.
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As one researcher I spoke to likes to say,
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"We were stressed,
but the whales weren't."
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Now you have to remember,
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we have evolved to be a visual species.
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We really rely on our eyes.
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But marine life relies on sound
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the way that we rely on sight.
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For them, a noisy ocean
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may be as befuddling and even dangerous
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as a dense fog is for us.
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And maybe sometimes that just means
being a little more stressed,
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maybe sometimes it means
spending a little less time with the kids.
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Maybe some species can adapt.
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But some researchers worry
that for endangered species
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already on the brink
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noise may be enough
to push them over the edge.
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So take for example,
the southern resident killer whales
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that live in the waters
off my home town of Vancouver.
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There are only 75, maybe 76 animals left
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in this population.
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And they're facing a lot of challenges.
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There are chemical pollutants
in these waters
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and they are running low on the salmon
that they really rely on for food.
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And then there's noise.
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When researchers studied these
and similar killer whales,
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they found that they spend
between 18 and 25 percent less time
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feeding in the presence
of loud boat noise.
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And that's a lot for a species
that's already struggling
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to find enough food to thrive.
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The good news, as I heard
from all the researches I spoke to,
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is that you can do something
relatively easily about ocean noise.
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Unlike the wicked problems
of climate change
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and ocean acidification,
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you can just dial down
the knob on ocean noise
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and see almost immediate impacts.
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So for example, in 2017,
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the Vancouver Fraser Port Authority
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started asking ships to simply slow down
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when going through the Haro Strait,
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where the southern resident killer whales
are feeding in late summer.
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Slower ships are quieter ships.
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And because it's Canada, you can just ask,
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it can be voluntary.
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(Laughter)
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(Applause)
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In that 2017 trial,
most of the ships complied,
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adding about half an hour
to their travel time,
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and reducing noise by about 1.2 decibels
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or 24 percent of noise intensity.
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This year, they decided
to extend the length of time
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and the area over which
they're asking ships to slow down.
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So hopefully, that has
a positive impact for these whales.
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In 2017, the Vancouver
Fraser Port Authority
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also introduced discounts in docking fees
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for ships that are physically
designed to be quieter.
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You know, weirdly, a lot of the noise
from a ship like this
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comes from the popping of tiny bubbles
off the back of its propeller.
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And you can simply design a ship
to do less of that
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and to be quieter.
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The International Maritime Organization
has published a huge list of ways
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that boats can be made quieter.
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And they also have a target
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of reducing carbon dioxide emissions
from global shipping
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by 50 percent by 2050.
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And the great news is that these
two things go hand in hand.
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On the whole, a more
efficient ship is a quieter ship.
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People have also invented quieter ways
of hammering in the giant posts
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needed for giant
wind turbines like this one.
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And gentler ways of doing seismic surveys.
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And there are some incentives
for using quieter technologies.
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The European Union, for example,
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has a healthy marine system
directive for 2020.
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And one of the ways that they define
a healthy marine system
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is by how much noise
is going in those waters.
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But on the whole, most waters
remain completely unregulated
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when it comes to ocean noise.
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But again, most of
the scientists I spoke to
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said that there's real momentum
right now in policy circles
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to pay attention to this issue
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and maybe do something about this issue.
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We already know enough to say
that quieter seas are healthier seas.
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But now scientists are really scrambling
to come up with the details.
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Just how quiet do we need to be?
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And where are the best places
to make quiet or preserve quiet?
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And how best can we hush our noise?
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And you know, I'm not trying to tell you
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that noise is the biggest
environmental problem on the planet
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or even in the ocean.
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But the point is that humankind
has a lot of impacts
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on our environmental system.
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And these impacts don't act in isolation.
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They act together and they multiply.
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So even for the ones
that are not so obvious,
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we really need to pay attention to them.
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I'll tell you about one last experiment,
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just because it's so beautiful.
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So Rob Williams,
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one of the researchers who works
on southern resident killer whales,
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also does some work in Bali.
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And there, they celebrate
a Hindu tradition
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called nyepi, or a day of silence.
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And this day, apparently,
is very strictly observed.
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No planes take off from he airport,
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no boats go out fishing,
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the tourists are gently led off the beach
back into their hotel rooms.
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And Rob Williams put some
hydrophones in the water there
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to see what the impact was,
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and it was dramatic.
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Sound levels dropped
by six to nine decibels,
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about the same
as in the waters after 9/11.
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For an "acoustic prospector"
like Williams,
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which is what he calls himself,
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this silence is golden.
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Now he and other researchers
can go bask to this place
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and see what the fish choose to do
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with all this additional
acoustic real estate.
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(Sounds of underwater)
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I like to think of them
having their own holiday,
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feasting and finding mates.
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Celebrating their own spot of calm
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in an otherwise noisy world.
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Thank you.
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(Applause)