Each day,
our sun gives rise to a resounding chorus
that continues around the globe,
24 hours a day,
365 days a year,
for millennia.
These are not some random collections of sounds.
These sounds are the living reflections
of evolution’s economy.
The costs and benefits imposed
by the Earth’s biological and physical environments.
I’m a bio-acoustics engineer.
I listen and study the songs and sounds of life.
In the ocean,
on land,
in the sky.
I didn’t start out planning
I was going to be a bio-acoustics engineer.
I was on my way to medical school, in 1972,
when I met two of the world’s leading whale scientists,
and they invited me to join them
on a National Geographic expedition,
to Patagonia, Argentina,
where they were about to study,
a long-term study,
on southern right whales.
I figured,
“This is a once-in-a-lifetime!”
And I accepted, knowing it was only going to last three months,
and then I’d go home and go to medical school.
We lived in tents, along this beach,
ate around a campfire at night,
beneath the Southern Cross,
and awakened each morning
to the sounds of whales, and elephant seals, and penguins.
It was in this magical place
that Roger Payne explained to me his hypothesis,
that prior to the advent of modern shipping,
and all the noise that ships make,
the songs of blue whales and fin whales
– these are the two largest animals ever to live on this planet –
could be heard across an ocean.
I was a little skeptical about this idea
that whale songs could travel thousands of miles through the ocean,
or that the noises from ships
could drown out their voices.
But I was enchanted by this idea.
And so, when I went home,
I never went to medical school.
Instead, I dove into the ocean,
excited by the possibilities
of listening to and discovering the songs and sounds of life.
After Argentina,
I went to the Arctic,
to study bowhead whales,
this is a relative of right whales.
And it was in the Arctic that I observed whales doing things
that were beyond my imagination.
Bowheads would migrate through massive fields of ice
using the echoes of their voices
to navigate in complete darkness.
It was in the Arctic that an Inupiat elder
explained to me, and I quote,
“The ears of the whale are sacred,
because the ears are the entrance to its soul.”
And it was in the Arctic
that I met and became friends with Doctor Bill Ellison,
a retired Navy Captain
and an expert in the physics of ocean sound.
And it was Bill who explained to me
how it was that a bowhead whale
could use the echoes of his voice off ice,
and a blue whale could use the reflections of its songs
off underwater mountains,
to navigate in the ocean.
And it was Bill who, in 1992,
recommended to the US Navy that they select me
to use their Underwater Sound Surveillance System,
known as SOSUS, to study whales.
The first time I tried to listen to a blue whale singing, using SOSUS,
all I heard was a giant hum.
I thought my equipment was broken,
so I checked the dials,
I checked the settings.
And everything seemed to be working.
And I knew the whales were singing out there,
because I could see their voices on the Navy display monitors.
And then, it hit me.
Of course I can’t hear a blue whale singing!
My ears and my mind
are completely out of tune, and out of touch, with a blue whale.
Its voice is below my hearing threshold.
A single note lasts 20 seconds,
and a song lasts for more than 20 minutes.
But I knew how to solve the problem.
I had to play back the recording at a much higher speed.
And when I did… voilà!
I heard the whale singing.
This is a voiceprint of that song.
It’s like a musical score.
Time runs along the bottom, from left to right,
and pitches low at the bottom,
and higher at the top.
I’m going to play you this song of the whale,
at 30 times faster than the original recording,
so you can hear it.
And, as you listen, consider this:
this whale is singing off the Grand Banks of Canada.
And its voice can be heard 3,000 miles away.
(Whale song)
The first time I heard this,
the hair went up on the back of my neck and it…
I still get chills remembering this moment,
because this was the moment, in 1992,
when I knew Roger’s hypothesis was true.
A blue whale can barely see its tail, 90 feet away,
but can communicate across an ocean with other blue whales.
In those early days using SOSUS,
I met and became friends with a lieutenant, Chuck Gagnon.
Chuck was a wizard at sound in the ocean
and at tracking submarines.
So I said to him: “Chuck,
what would you do if you had a voice as loud and as low as a blue whale’s?”
He didn’t hesitate to answer me, [and] this is what he said:
“I could illuminate the ocean.”
You see what he did?
He translated the acoustic radiance of the whale’s voice, its song,
into a visual image of how it would let him see the ocean.
It’s like sonar, only on a massive scale.
So I asked him,
“Well, Chuck, can you show me what this would look like?”
This is what he showed me.
The red circle at the bottom of the screen
is where a blue whale is singing, off the Virgin Islands.
Notice the blue concentric circles emanating out from the whale.
They represent how loud that song is, throughout the ocean.
And notice how the energy points out
the continental shelf of the United States,
running from Florida,
all the way up around to the Grand Banks of Canada.
Notice how the Island of Bermuda,
that’s the blue circle in the middle of the screen,
casts a white acoustic shadow to the North, in which no sound appears.
And look over to the right
and notice the jagged edges in the reflections,
identifying an underwater mountain range,
known as the Mid-Atlantic Ridge.
This was amazing to me.
So, I challenged them again.
I said, “Well, Chuck, can you track one of these whales,
whose voices we are seeing on the monitors?”
He sort of chuckled and said,
“No problem. Piece of cake.”
A few months later,
he showed me this track of a whale he named Old Blue.
Old Blue was a whale singing across the ocean to find a mate.
Chuck tracked Old Blue for 43 days,
as he sang and swam 1,700 miles through the ocean,
that’s the distance from here in Atlanta all the way to Los Angeles.
Chuck didn’t need to see the whale.
He didn’t need to touch the whale.
He just had to listen to the whale.
This is a one-year voiceprint from the Pacific Ocean.
20 is the lowest frequency, or pitch, that you can hear.
440 is orchestral A,
for those of you who are musicians.
The yellow striations that are dripping from the top of the picture
represent the acoustic energy from ocean storms, throughout the year.
And notice the yellow glow in the lower right,
sort of this aurora borealis.
That is the acoustic energy
from a population of singing blue whales
and a population of singing fin whales.
This chorus lasts for four [weeks],
starting in December, and ending in January.
Chuck and I have been working together for over 25 years.
It was Chuck who taught me to think of SOSUS,
the Sound Surveilliance System,
as a giant acoustic antenna,
or a telescope.
Chuck drills down into the visual images
that he finds in the telescope’s visual displays,
and I drill down into the voiceprints
to discover and listen to what they are.
One can’t observe the ocean
at such immense spatial and temporal scales,
without becoming very aware of hearing and “seeing”
all the racket from human activities.
There are large areas of the ocean now
that are acoustically urbanized and acoustically industrialized.
Over 90% of global commerce travels on ships.
Almost all the ways we use in the ocean
for communication, navigation, defense, finding food,
use some form of relatively intense sound.
Our explorations for hydrocarbons, oil and gas,
beneath the seafloor,
use explosions from airguns every 9 to12 seconds,
for weeks and weeks and months at a time.
You’ll also hear the sonar pings from the ships’ navigation system.
Almost all marine animals
– whales,
seals, fish, shrimp –
use sounds for all the essential activities of life:
communication, navigation,
defense, finding food,
maintaining social networks.
We do not yet know the real consequences,
the ecological cost of our acoustic invasion.
We do know that some animals die, some animals flee,
and some seem to be relatively tolerant of all our acoustic pollution.
This is my simplistic way of showing you
the impact of our noise
on the communication space of blue whales.
The large, green area on the left
shows you the space over which blue whales could communicate
under a quiet, pre-shipping condition.
The smaller green area on the right,
shows you that space under present conditions.
So what?
Why should we care of all the noise we’re dumping into the ocean?
It’s making it difficult for life to hear and be heard.
I have a hypothesis.
While Chuck was looking into the ocean, using the acoustic telescope,
he detected an interesting phenomenon.
It was a bloom of acoustic energy that showed up on the voiceprints.
It arose after sunset,
and lasted for several hours into the night.
But when we listened, there was nothing there!
But we could see it on the voiceprint.
It turns out we were detecting the noise
from thousands and thousands of sea urchins,
scraping algae off rocks and coral.
Isn’t that amazing?
We were listening to sea urchins!
So, this really got our attention,
and Chuck started looking
for other glows of acoustic energy that we could not recognize.
And he found one.
And it wasn’t sea urchins,
because this time the telescope was pointing into the deep ocean,
where there are no islands, no reefs, no sea urchins.
It turns out, I think,
we are detecting a phenomenon
that occurs when billions and billions of organisms
move upward towards the surface of the ocean at night,
and then disappear and descend into the depths of the ocean,
during the day.
Every day, 365 days a year,
for millions and millions of years.
This phenomenon was detected by the U.S. Navy
during the Second World War,
when they were using anti-submarine sonar.
It’s called “the deep scattering layer.”
We can detect this phenomenon in the voiceprints,
when the ocean is quiet.
These organisms, going up and down,
depend on tiny exotic forms of life
such as these diatoms,
that live in the upper layers of the ocean,
that convert carbon dioxide into oxygen.
Some of you may know this,
but every other breath you take, right here, all day,
comes from these tiny, microscopic, exotic forms of life.
We are listening to the voice of the ocean,
breathing.
This is more than just amazing!
This is literally our breath of life.
We are wise to pay attention
to the light we cannot see, to the sounds we cannot hear,
and to the life we know is there,
and on which our lives, all our lives, depend.
Thank you very much.
(Applause)
”
Be First to Comment