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CHRISTOPHER W. CLARK: I was given the extraordinary opportunity to use the US Navy's antisubmarine listening system that was developed and deployed over 40 years. And it's a network of sensors, underwater hydrophones, listening microphones, on the bottom of the ocean all over the North Atlantic and all over the North Pacific. And I was given the challenge by then Vise President Gore to answer the question whether or not such a system, that was designed to listen for and track and keep tabs on quiet submarines, whether or not it could actually be used to listen and track and locate the voices of the great whales.
Now these are animals that are advertising themselves to as large an audience as they possibly can. Their voices just resonate throughout the ocean. So, of course, the answer was a resounding yes. And I can remember the very first time when, lo and behold, I realized I was looking at a spectrogram, a sound print, a voice print, of a whale that was actually 1,600 miles away.
But in any case, there I was, listening to the ocean and suddenly my mind just had to flip inside out because instead of thinking of my world or the world of the whales as my world, which was out as far as I could see or out as far as I could hear, suddenly I was invited into this world where, my goodness, I can hear an animal across an ocean. I can listen to an animal that's hundreds of miles away-- in fact, sometimes thousands of miles away. So isn't this their world? Isn't this the world that the whales had come to know and had evolved in and were taking advantage of?
So what you're looking at here, this image is a spectrogram. This is a voiceprint, if you will, a picture of one year's worth of sound recording converted into an image, where the lightness here represents the collective voices of a population of whales singing, not just one whale, and actually not just one population. There are actually two species in here and I don't know if you can look really, really carefully, right here, there's a very thin yellow line. And that represents the very high frequency note of the blue whales singing in the North Atlantic and it represents the notes of lots of voices. This is four months' worth of singing. It's the same thing we all know that happens in the spring, when the peepers all light up the ponds around Ithaca or the birds all migrate into town and take up their residency and start singing and proclaiming that they are the ones to mate with.
Now let me show you this scene, which is an image lifted from the National Geographic and it shows Africa, Europe, here's Great Britain. Go across the Atlantic Ocean, there's the mid-Atlantic ridge. That's the stretch mark of the Earth's crust, which constantly spreading. Here is the Caribbean area, Florida, New York, and up here is Nova Scotia and Labrador and the Canadian arctic. This is the home range of the blue whale. This is their backyard.
So when I was saying I listened to a whale 1,600 miles away, the blue whale was singing on the Grand Banks. I was listening to it off of Puerto Rico. Is that I can actually position where the whale is singing and I'm going to show you. Here is a map of whales, singing blue whales, west of Ireland. Here's Ireland, here is England and Scotland. So this is the British Isles and the blue represents very deep water. Here is the mid-Atlantic ridge, stretching right along here and then going up through Iceland. And each of these dots represents the position of a singing blue whale within a three hour period, right?
So you can see, now in this case, I positioned the same whale three times. So this is the same whale, this is the same whale, this is the same whale, this is the same whale. This is a group of animals. And here you see, so there are probably roughly about eight or 10 animals in this picture, but I can position each one of those singing whales and show where they are in the ocean. So it's the same thing we would do on land, but at a much smaller scale on land. Now we're doing it over hundreds of thousands of square miles. I'm going to show you what happens when I open the shutter and position all the singers every three hours. You're going to see the animals moving around.
And one of the reasons I was plotting this and tracking all these whales and taking the time to do this meticulous work was trying to answer the question, hey are the whales communicating? If I'm over here off Ireland and you're over here off the mid-Atlantic ridge and I can hear you and you can hear me, are we really communicating? Is there anything you're doing that's going to change my behavior? Because that's an important question because, until we understand over what scales, what distances these animals are communicating, I can't interpret that and understand what's the impact of all the noise that we're generating in the ocean now from all our shipping.
So I'm trying to answer the question how far away can I not just hear you, but how far away am I communicating with you? And if we're communicating over those distances, well, what are we saying? What's the message? In this case, it's very simple. I'm identifying myself as a blue whale, I'm a male singer, I might very well have found a large, good patch of food because what's happening here is, this is where they're actually feeding. So the singing animals are associated with food resources and maybe there's something about my song and the way I'm behaving that is indicative of my fitness and the quality of the food patch that I'm presently swimming in.
And it's really hard to get across the notion of well what is the acoustic-- so what if a ship makes a little bit of noise or so what if we go out there and explore for oil and gas and we're making lots of explosions every 11 seconds? And it's really hard for us, as a visual beast, and we are visual animals. These whales rely on sound to communicate, to maintain their social systems, to detect predators, to find food. All the basic life functions that we are so familiar with but for which we use our eyes, they rely on their ears. So if they can't hear each other because of all the noise and the clutter, suddenly they're compromised. It might be harder for them to find food.
Again, it's a visual representation of the noise habitat where this is time, this is one day, a 24 hour period, and this is frequency or pitch. And this is all low frequency. And there you see I call this a rural habitat because here you see lots of deep blue, representing quiet ocean, normal, quiet ocean. And down here, you see all this glow of the yellow and the orange and the red. Well, this represents the collective voices of the singing whales. In this case, these are all singing fin whales. And this was recorded in the Sea of Cortez, this is the Gulf of California where John Steinbeck wrote his books.
And here is another habitat. This is an urban habitat. This is the Mediterranean Sea. Fin whales live there too but so do a lot of humans. And here what you're seeing is all the noise from the collective shipping activities and ferry boats and bay boats and whatnot. This is all the clutter.
So in a very simple kind of representation, the area over which blue whales could communicate once upon a time, 100 years ago, 60 years ago, prior to shipping, is the size of this red circle, the area underneath this red circle. So here's Florida, the East Coast of the United States, New York is up here, Cape Cod, Boston, and then up into Canada. And there's Cuba and the mid-Atlantic ridge. So this is a reasonable area, of course, that whales can hear each other because I can hear whales singing here. I can hear that whale off of Puerto Rico.
But today, z this is a typical day when the noise level goes up and it's constantly bombarded by the groaning and grinding of ships. So pretty much, the whales are reduced to a dramatically smaller portion of their acoustic habitat that they would normally have had 100 years ago. And remember, these animals live to be 100 and 150 years. So when the animal was a teenager and it might have enjoyed this kind of space, today, because of all the shipping noise, all the traffic that brings the goods and services to Wal-Marts and Home Depots, et cetera, that's its world.
Some in the shipping industry have gotten wiser and they've said wait a minute, let's slow down. Let's only go 18 knots because z the ship is optimally designed for that speed. We burn less fuel and we can actually get to market if we plan what we're going to do when we get there. We can get the market just as fast. And they're actually some of these numbers are quite astounding, where they're saving over $1 billion a year just by going slower.
Now that kind of economics, that kind of money saving, starts to talk and starts to make a difference, especially when you realize that going faster, you burn more fuel, you're just making more noise, and then you get there and you have to wait. And at least now, the industry and the shippers are now opening the door and saying, oh, we're willing to have a discussion about this and they had no idea that they were making this much noise. They had no idea that they were actually impacting whales. So there's hope, you know?
Using the Navy's underwater submarine listening system, Christopher Clark has been able to track deep water whales, like the blue whale and fin whale, throughout the ocean basins.
These animals use sound to communicate over very long distances; for example, a whale singing off the Grand Banks of Canada can be detected in Puerto Rico! But as the number and noise of commercial ships has increased, it is likely to interfere with the whale's ability to hear one another. What the long term effect of this will be on the whales is largely unknown.
