WEBVTT 00:00:00.000 --> 00:00:03.000 Thank you so much. I'm going to try to take you 00:00:03.000 --> 00:00:06.000 on a journey of the underwater acoustic world 00:00:06.000 --> 00:00:08.000 of whales and dolphins. 00:00:08.000 --> 00:00:10.000 Since we are such a visual species, 00:00:10.000 --> 00:00:12.000 it's hard for us to really understand this, 00:00:12.000 --> 00:00:14.000 so I'll use a mixture of figures and sounds 00:00:14.000 --> 00:00:16.000 and hope this can communicate it. 00:00:16.000 --> 00:00:19.000 But let's also think, as a visual species, 00:00:19.000 --> 00:00:21.000 what it's like when we go snorkeling or diving 00:00:21.000 --> 00:00:23.000 and try to look underwater. 00:00:23.000 --> 00:00:25.000 We really can't see very far. 00:00:25.000 --> 00:00:27.000 Our vision, which works so well in air, 00:00:27.000 --> 00:00:30.000 all of a sudden is very restricted and claustrophobic. 00:00:30.000 --> 00:00:32.000 And what marine mammals have evolved 00:00:32.000 --> 00:00:35.000 over the last tens of millions of years 00:00:35.000 --> 00:00:37.000 is ways to depend on sound 00:00:37.000 --> 00:00:39.000 to both explore their world 00:00:39.000 --> 00:00:41.000 and also to stay in touch with one another. NOTE Paragraph 00:00:41.000 --> 00:00:43.000 Dolphins and toothed whales use echolocation. 00:00:43.000 --> 00:00:45.000 They can produce loud clicks 00:00:45.000 --> 00:00:48.000 and listen for echoes from the sea floor in order to orient. 00:00:48.000 --> 00:00:50.000 They can listen for echoes from prey 00:00:50.000 --> 00:00:52.000 in order to decide where food is 00:00:52.000 --> 00:00:55.000 and to decide which one they want to eat. 00:00:55.000 --> 00:00:57.000 All marine mammals use sound for communication to stay in touch. 00:00:57.000 --> 00:00:59.000 So the large baleen whales 00:00:59.000 --> 00:01:02.000 will produce long, beautiful songs, 00:01:02.000 --> 00:01:04.000 which are used in reproductive advertisement 00:01:04.000 --> 00:01:06.000 for male and females, both to find one another 00:01:06.000 --> 00:01:08.000 and to select a mate. 00:01:08.000 --> 00:01:10.000 And mother and young and closely bonded animals 00:01:10.000 --> 00:01:13.000 use calls to stay in touch with one another, 00:01:13.000 --> 00:01:15.000 so sound is really critical for their lives. NOTE Paragraph 00:01:15.000 --> 00:01:17.000 The first thing that got me interested in the sounds 00:01:17.000 --> 00:01:19.000 of these underwater animals, 00:01:19.000 --> 00:01:21.000 whose world was so foreign to me, 00:01:21.000 --> 00:01:23.000 was evidence from captive dolphins 00:01:23.000 --> 00:01:26.000 that captive dolphins could imitate human sounds. 00:01:26.000 --> 00:01:28.000 And I mentioned I'll use 00:01:28.000 --> 00:01:30.000 some visual representations of sounds. 00:01:30.000 --> 00:01:32.000 Here's the first example. 00:01:32.000 --> 00:01:34.000 This is a plot of frequency against time -- 00:01:34.000 --> 00:01:36.000 sort of like musical notation, 00:01:36.000 --> 00:01:39.000 where the higher notes are up higher and the lower notes are lower, 00:01:39.000 --> 00:01:41.000 and time goes this way. 00:01:41.000 --> 00:01:43.000 This is a picture of a trainer's whistle, 00:01:43.000 --> 00:01:45.000 a whistle a trainer will blow to tell a dolphin 00:01:45.000 --> 00:01:47.000 it's done the right thing and can come get a fish. 00:01:47.000 --> 00:01:50.000 It sounds sort of like "tweeeeeet." Like that. 00:01:50.000 --> 00:01:52.000 This is a calf in captivity 00:01:52.000 --> 00:01:54.000 making an imitation 00:01:54.000 --> 00:01:56.000 of that trainer's whistle. 00:01:56.000 --> 00:01:58.000 If you hummed this tune to your dog or cat 00:01:58.000 --> 00:02:00.000 and it hummed it back to you, 00:02:00.000 --> 00:02:02.000 you ought to be pretty surprised. 00:02:02.000 --> 00:02:04.000 Very few nonhuman mammals 00:02:04.000 --> 00:02:06.000 can imitate sounds. 00:02:06.000 --> 00:02:08.000 It's really important for our music and our language. NOTE Paragraph 00:02:08.000 --> 00:02:11.000 So it's a puzzle: The few other mammal groups that do this, 00:02:11.000 --> 00:02:13.000 why do they do it? 00:02:13.000 --> 00:02:15.000 A lot of my career has been devoted 00:02:15.000 --> 00:02:17.000 to trying to understand 00:02:17.000 --> 00:02:19.000 how these animals use their learning, 00:02:19.000 --> 00:02:21.000 use the ability to change what you say 00:02:21.000 --> 00:02:23.000 based on what you hear 00:02:23.000 --> 00:02:25.000 in their own communication systems. 00:02:25.000 --> 00:02:28.000 So let's start with calls of a nonhuman primate. 00:02:28.000 --> 00:02:30.000 Many mammals have to produce contact calls 00:02:30.000 --> 00:02:33.000 when, say, a mother and calf are apart. 00:02:33.000 --> 00:02:36.000 This is an example of a call produced by squirrel monkeys 00:02:36.000 --> 00:02:38.000 when they're isolated from another one. 00:02:38.000 --> 00:02:40.000 And you can see, there's not much 00:02:40.000 --> 00:02:42.000 variability in these calls. 00:02:42.000 --> 00:02:44.000 By contrast, the signature whistle 00:02:44.000 --> 00:02:46.000 which dolphins use to stay in touch, 00:02:46.000 --> 00:02:49.000 each individual here has a radically different call. 00:02:49.000 --> 00:02:52.000 They can use this ability to learn calls 00:02:52.000 --> 00:02:55.000 in order to develop more complicated and more distinctive calls 00:02:55.000 --> 00:02:57.000 to identify individuals. NOTE Paragraph 00:02:58.000 --> 00:03:01.000 How about the setting in which animals need to use this call? 00:03:01.000 --> 00:03:03.000 Well let's look at mothers and calves. 00:03:03.000 --> 00:03:05.000 In normal life for mother and calf dolphin, 00:03:05.000 --> 00:03:08.000 they'll often drift apart or swim apart if Mom is chasing a fish, 00:03:08.000 --> 00:03:10.000 and when they separate 00:03:10.000 --> 00:03:12.000 they have to get back together again. 00:03:12.000 --> 00:03:15.000 What this figure shows is the percentage of the separations 00:03:15.000 --> 00:03:17.000 in which dolphins whistle, 00:03:17.000 --> 00:03:19.000 against the maximum distance. 00:03:19.000 --> 00:03:21.000 So when dolphins are separating by less than 20 meters, 00:03:21.000 --> 00:03:23.000 less than half the time they need to use whistles. 00:03:23.000 --> 00:03:25.000 Most of the time they can just find each other 00:03:25.000 --> 00:03:27.000 just by swimming around. 00:03:27.000 --> 00:03:30.000 But all of the time when they separate by more than 100 meters, 00:03:30.000 --> 00:03:33.000 they need to use these individually distinctive whistles 00:03:33.000 --> 00:03:36.000 to come back together again. 00:03:36.000 --> 00:03:38.000 Most of these distinctive signature whistles 00:03:38.000 --> 00:03:40.000 are quite stereotyped and stable 00:03:40.000 --> 00:03:42.000 through the life of a dolphin. 00:03:42.000 --> 00:03:44.000 But there are some exceptions. NOTE Paragraph 00:03:44.000 --> 00:03:46.000 When a male dolphin leaves Mom, 00:03:46.000 --> 00:03:48.000 it will often join up with another male 00:03:48.000 --> 00:03:51.000 and form an alliance, which may last for decades. 00:03:51.000 --> 00:03:54.000 As these two animals form a social bond, 00:03:54.000 --> 00:03:56.000 their distinctive whistles actually converge 00:03:56.000 --> 00:03:58.000 and become very similar. 00:03:58.000 --> 00:04:01.000 This plot shows two members of a pair. 00:04:01.000 --> 00:04:03.000 As you can see at the top here, 00:04:03.000 --> 00:04:05.000 they share an up-sweep, like "woop, woop, woop." 00:04:05.000 --> 00:04:07.000 They both have that kind of up-sweep. 00:04:07.000 --> 00:04:10.000 Whereas these members of a pair go "wo-ot, wo-ot, wo-ot." 00:04:10.000 --> 00:04:12.000 And what's happened is 00:04:12.000 --> 00:04:14.000 they've used this learning process 00:04:14.000 --> 00:04:17.000 to develop a new sign that identifies this new social group. 00:04:17.000 --> 00:04:19.000 It's a very interesting way that they can 00:04:19.000 --> 00:04:21.000 form a new identifier 00:04:21.000 --> 00:04:23.000 for the new social group that they've had. NOTE Paragraph 00:04:23.000 --> 00:04:25.000 Let's now take a step back 00:04:25.000 --> 00:04:27.000 and see what this message can tell us 00:04:27.000 --> 00:04:29.000 about protecting dolphins 00:04:29.000 --> 00:04:31.000 from human disturbance. 00:04:31.000 --> 00:04:33.000 Anybody looking at this picture 00:04:33.000 --> 00:04:35.000 will know this dolphin is surrounded, 00:04:35.000 --> 00:04:38.000 and clearly his behavior is being disrupted. 00:04:38.000 --> 00:04:40.000 This is a bad situation. 00:04:40.000 --> 00:04:42.000 But it turns out that when just a single boat 00:04:42.000 --> 00:04:44.000 is approaching a group of dolphins 00:04:44.000 --> 00:04:46.000 at a couple hundred meters away, 00:04:46.000 --> 00:04:48.000 the dolphins will start whistling, 00:04:48.000 --> 00:04:50.000 they'll change what they're doing, they'll have a more cohesive group, 00:04:50.000 --> 00:04:52.000 wait for the boat to go by, 00:04:52.000 --> 00:04:54.000 and then they'll get back to normal business. 00:04:54.000 --> 00:04:56.000 Well, in a place like Sarasota, Florida, 00:04:56.000 --> 00:04:58.000 the average interval between times 00:04:58.000 --> 00:05:01.000 that a boat is passing within a hundred meters of a dolphin group 00:05:01.000 --> 00:05:03.000 is six minutes. 00:05:03.000 --> 00:05:06.000 So even in the situation that doesn't look as bad as this, 00:05:06.000 --> 00:05:08.000 it's still affecting the amount of time these animals have 00:05:08.000 --> 00:05:10.000 to do their normal work. NOTE Paragraph 00:05:10.000 --> 00:05:13.000 And if we look at a very pristine environment like western Australia, 00:05:13.000 --> 00:05:15.000 Lars Bider has done work 00:05:15.000 --> 00:05:18.000 comparing dolphin behavior and distribution 00:05:18.000 --> 00:05:21.000 before there were dolphin-watching boats. 00:05:21.000 --> 00:05:24.000 When there was one boat, not much of an impact. 00:05:24.000 --> 00:05:27.000 And two boats: When the second boat was added, 00:05:27.000 --> 00:05:29.000 what happened was that some of the dolphins 00:05:29.000 --> 00:05:31.000 left the area completely. 00:05:31.000 --> 00:05:34.000 Of the ones that stayed, their reproductive rate declined. 00:05:34.000 --> 00:05:37.000 So it could have a negative impact on the whole population. 00:05:37.000 --> 00:05:40.000 When we think of marine-protected areas for animals like dolphins, 00:05:40.000 --> 00:05:42.000 this means that we have to be 00:05:42.000 --> 00:05:45.000 quite conscious about activities that we thought were benign. 00:05:45.000 --> 00:05:47.000 We may need to regulate the intensity 00:05:47.000 --> 00:05:50.000 of recreational boating and actual whale watching 00:05:50.000 --> 00:05:53.000 in order to prevent these kinds of problems. 00:05:53.000 --> 00:05:55.000 I'd also like to point out that sound 00:05:55.000 --> 00:05:57.000 doesn't obey boundaries. 00:05:57.000 --> 00:06:00.000 So you can draw a line to try to protect an area, 00:06:00.000 --> 00:06:02.000 but chemical pollution and noise pollution 00:06:02.000 --> 00:06:04.000 will continue to move through the area. NOTE Paragraph 00:06:04.000 --> 00:06:06.000 And I'd like to switch now from this local, 00:06:06.000 --> 00:06:09.000 familiar, coastal environment 00:06:09.000 --> 00:06:12.000 to a much broader world of the baleen whales and the open ocean. 00:06:12.000 --> 00:06:15.000 This is a kind of map we've all been looking at. 00:06:15.000 --> 00:06:17.000 The world is mostly blue. 00:06:17.000 --> 00:06:19.000 But I'd also like to point out that the oceans 00:06:19.000 --> 00:06:21.000 are much more connected than we think. 00:06:21.000 --> 00:06:24.000 Notice how few barriers there are to movement 00:06:24.000 --> 00:06:26.000 across all of the oceans compared to land. 00:06:26.000 --> 00:06:28.000 To me, the most mind-bending example 00:06:28.000 --> 00:06:30.000 of the interconnectedness of the ocean 00:06:30.000 --> 00:06:32.000 comes from an acoustic experiment 00:06:32.000 --> 00:06:34.000 where oceanographers 00:06:34.000 --> 00:06:37.000 took a ship to the southern Indian Ocean, 00:06:37.000 --> 00:06:39.000 deployed an underwater loudspeaker 00:06:39.000 --> 00:06:41.000 and played back a sound. 00:06:41.000 --> 00:06:43.000 That same sound 00:06:43.000 --> 00:06:46.000 traveled to the west, and could be heard in Bermuda, 00:06:46.000 --> 00:06:49.000 and traveled to the east, and could be heard in Monterey -- 00:06:49.000 --> 00:06:51.000 the same sound. NOTE Paragraph 00:06:51.000 --> 00:06:53.000 So we live in a world of satellite communication, 00:06:53.000 --> 00:06:55.000 are used to global communication, 00:06:55.000 --> 00:06:57.000 but it's still amazing to me. 00:06:57.000 --> 00:06:59.000 The ocean has properties 00:06:59.000 --> 00:07:01.000 that allow low-frequency sound 00:07:01.000 --> 00:07:03.000 to basically move globally. 00:07:03.000 --> 00:07:06.000 The acoustic transit time for each of these paths is about three hours. 00:07:06.000 --> 00:07:09.000 It's nearly halfway around the globe. 00:07:09.000 --> 00:07:11.000 In the early '70s, 00:07:11.000 --> 00:07:13.000 Roger Payne and an ocean acoustician 00:07:13.000 --> 00:07:15.000 published a theoretical paper 00:07:15.000 --> 00:07:17.000 pointing out that it was possible 00:07:17.000 --> 00:07:20.000 that sound could transmit over these large areas, 00:07:20.000 --> 00:07:23.000 but very few biologists believed it. NOTE Paragraph 00:07:23.000 --> 00:07:25.000 It actually turns out, though, 00:07:25.000 --> 00:07:28.000 even though we've only known of long-range propagation for a few decades, 00:07:28.000 --> 00:07:31.000 the whales clearly have evolved, 00:07:31.000 --> 00:07:33.000 over tens of millions of years, 00:07:33.000 --> 00:07:36.000 a way to exploit this amazing property of the ocean. 00:07:36.000 --> 00:07:38.000 So blue whales and fin whales 00:07:38.000 --> 00:07:40.000 produce very low-frequency sounds 00:07:40.000 --> 00:07:42.000 that can travel over very long ranges. 00:07:42.000 --> 00:07:44.000 The top plot here shows 00:07:44.000 --> 00:07:46.000 a complicated series of calls 00:07:46.000 --> 00:07:48.000 that are repeated by males. 00:07:48.000 --> 00:07:51.000 They form songs, and they appear to play a role in reproduction, 00:07:51.000 --> 00:07:53.000 sort of like that of song birds. 00:07:53.000 --> 00:07:56.000 Down below here, we see calls made by both males and females 00:07:56.000 --> 00:07:59.000 that also carry over very long ranges. NOTE Paragraph 00:08:00.000 --> 00:08:02.000 The biologists continued to be skeptical 00:08:02.000 --> 00:08:04.000 of the long-range communication issue 00:08:04.000 --> 00:08:06.000 well past the '70s, 00:08:06.000 --> 00:08:08.000 until the end of the Cold War. 00:08:08.000 --> 00:08:10.000 What happened was, during the Cold War, 00:08:10.000 --> 00:08:13.000 the U.S. Navy had a system that was secret at the time, 00:08:13.000 --> 00:08:16.000 that they used to track Russian submarines. 00:08:16.000 --> 00:08:18.000 It had deep underwater microphones, or hydrophones, 00:08:18.000 --> 00:08:20.000 cabled to shore, 00:08:20.000 --> 00:08:22.000 all wired back to a central place that could listen 00:08:22.000 --> 00:08:24.000 to sounds over the whole North Atlantic. 00:08:24.000 --> 00:08:27.000 And after the Berlin Wall fell, the Navy made these systems available 00:08:27.000 --> 00:08:29.000 to whale bio-acousticians 00:08:29.000 --> 00:08:31.000 to see what they could hear. NOTE Paragraph 00:08:31.000 --> 00:08:33.000 This is a plot from Christopher Clark 00:08:33.000 --> 00:08:36.000 who tracked one individual blue whale 00:08:36.000 --> 00:08:38.000 as it passed by Bermuda, 00:08:38.000 --> 00:08:41.000 went down to the latitude of Miami and came back again. 00:08:41.000 --> 00:08:43.000 It was tracked for 43 days, 00:08:43.000 --> 00:08:45.000 swimming 1,700 kilometers, 00:08:45.000 --> 00:08:47.000 or more than 1,000 miles. 00:08:47.000 --> 00:08:49.000 This shows us both that the calls 00:08:49.000 --> 00:08:51.000 are detectable over hundreds of miles 00:08:51.000 --> 00:08:53.000 and that whales routinely swim hundreds of miles. 00:08:53.000 --> 00:08:55.000 They're ocean-based and scale animals 00:08:55.000 --> 00:08:57.000 who are communicating over much longer ranges 00:08:57.000 --> 00:08:59.000 than we had anticipated. NOTE Paragraph 00:08:59.000 --> 00:09:01.000 Unlike fins and blues, which 00:09:01.000 --> 00:09:03.000 disperse into the temperate and tropical oceans, 00:09:03.000 --> 00:09:05.000 the humpbacked whales congregate 00:09:05.000 --> 00:09:08.000 in local traditional breeding grounds, 00:09:08.000 --> 00:09:11.000 so they can make a sound that's a little higher in frequency, 00:09:11.000 --> 00:09:13.000 broader-band and more complicated. 00:09:13.000 --> 00:09:15.000 So you're listening to the complicated song 00:09:15.000 --> 00:09:17.000 produced by humpbacks here. 00:09:17.000 --> 00:09:19.000 Humpbacks, when they develop 00:09:19.000 --> 00:09:21.000 the ability to sing this song, 00:09:21.000 --> 00:09:23.000 they're listening to other whales 00:09:23.000 --> 00:09:26.000 and modifying what they sing based on what they're hearing, 00:09:26.000 --> 00:09:29.000 just like song birds or the dolphin whistles I described. 00:09:29.000 --> 00:09:31.000 This means that humpback song 00:09:31.000 --> 00:09:33.000 is a form of animal culture, 00:09:33.000 --> 00:09:35.000 just like music for humans would be. NOTE Paragraph 00:09:35.000 --> 00:09:38.000 I think one of the most interesting examples of this 00:09:38.000 --> 00:09:40.000 comes from Australia. 00:09:40.000 --> 00:09:42.000 Biologists on the east coast of Australia 00:09:42.000 --> 00:09:45.000 were recording the songs of humpbacks in that area. 00:09:45.000 --> 00:09:48.000 And this orange line here marks the typical songs 00:09:48.000 --> 00:09:50.000 of east coast humpbacks. 00:09:50.000 --> 00:09:52.000 In '95 they all sang the normal song. 00:09:52.000 --> 00:09:54.000 But in '96 they heard a few weird songs, 00:09:54.000 --> 00:09:57.000 and it turned out that these strange songs 00:09:57.000 --> 00:09:59.000 were typical of west coast whales. 00:09:59.000 --> 00:10:02.000 The west coast calls became more and more popular, 00:10:02.000 --> 00:10:04.000 until by 1998, 00:10:04.000 --> 00:10:07.000 none of the whales sang the east coast song; it was completely gone. 00:10:07.000 --> 00:10:09.000 They just sang the cool new west coast song. 00:10:09.000 --> 00:10:11.000 It's as if some new hit style 00:10:11.000 --> 00:10:13.000 had completely wiped out 00:10:13.000 --> 00:10:15.000 the old-fashioned style before, 00:10:15.000 --> 00:10:17.000 and with no golden oldies stations. 00:10:17.000 --> 00:10:20.000 Nobody sang the old ones. NOTE Paragraph 00:10:20.000 --> 00:10:23.000 I'd like to briefly just show what the ocean does to these calls. 00:10:23.000 --> 00:10:26.000 Now you are listening to a recording made by Chris Clark, 00:10:26.000 --> 00:10:29.000 0.2 miles away from a humpback. 00:10:29.000 --> 00:10:32.000 You can hear the full frequency range. It's quite loud. 00:10:32.000 --> 00:10:34.000 You sound very nearby. 00:10:34.000 --> 00:10:36.000 The next recording you're going to hear 00:10:36.000 --> 00:10:38.000 was made of the same humpback song 00:10:38.000 --> 00:10:40.000 50 miles away. 00:10:40.000 --> 00:10:42.000 That's shown down here. 00:10:42.000 --> 00:10:44.000 You only hear the low frequencies. 00:10:44.000 --> 00:10:46.000 You hear the reverberation 00:10:46.000 --> 00:10:48.000 as the sound travels over long-range in the ocean 00:10:48.000 --> 00:10:51.000 and is not quite as loud. 00:10:51.000 --> 00:10:54.000 Now after I play back these humpback calls, 00:10:54.000 --> 00:10:57.000 I'll play blue whale calls, but they have to be sped up 00:10:57.000 --> 00:10:59.000 because they're so low in frequency 00:10:59.000 --> 00:11:01.000 that you wouldn't be able to hear it otherwise. 00:11:01.000 --> 00:11:03.000 Here's a blue whale call at 50 miles, 00:11:03.000 --> 00:11:05.000 which was distant for the humpback. 00:11:05.000 --> 00:11:08.000 It's loud, clear -- you can hear it very clearly. 00:11:08.000 --> 00:11:11.000 Here's the same call recorded from a hydrophone 00:11:11.000 --> 00:11:13.000 500 miles away. 00:11:13.000 --> 00:11:16.000 There's a lot of noise, which is mostly other whales. 00:11:16.000 --> 00:11:19.000 But you can still hear that faint call. NOTE Paragraph 00:11:19.000 --> 00:11:21.000 Let's now switch and think about 00:11:21.000 --> 00:11:23.000 a potential for human impacts. 00:11:23.000 --> 00:11:26.000 The most dominant sound that humans put into the ocean 00:11:26.000 --> 00:11:28.000 comes from shipping. 00:11:28.000 --> 00:11:30.000 This is the sound of a ship, 00:11:30.000 --> 00:11:32.000 and I'm having to talk a little louder to talk over it. 00:11:32.000 --> 00:11:35.000 Imagine that whale listening from 500 miles. 00:11:35.000 --> 00:11:37.000 There's a potential problem that maybe 00:11:37.000 --> 00:11:39.000 this kind of shipping noise would prevent whales 00:11:39.000 --> 00:11:41.000 from being able to hear each other. 00:11:41.000 --> 00:11:43.000 Now this is something that's been known for quite a while. NOTE Paragraph 00:11:43.000 --> 00:11:46.000 This is a figure from a textbook on underwater sound. 00:11:46.000 --> 00:11:48.000 And on the y-axis 00:11:48.000 --> 00:11:51.000 is the loudness of average ambient noise in the deep ocean 00:11:51.000 --> 00:11:53.000 by frequency. 00:11:53.000 --> 00:11:56.000 In the low frequencies, this line indicates 00:11:56.000 --> 00:11:59.000 sound that comes from seismic activity of the earth. 00:11:59.000 --> 00:12:01.000 Up high, these variable lines 00:12:01.000 --> 00:12:04.000 indicate increasing noise in this frequency range 00:12:04.000 --> 00:12:06.000 from higher wind and wave. 00:12:06.000 --> 00:12:09.000 But right in the middle here where there's a sweet spot, 00:12:09.000 --> 00:12:11.000 the noise is dominated by human ships. 00:12:11.000 --> 00:12:13.000 Now think about it. This is an amazing thing: 00:12:13.000 --> 00:12:16.000 That in this frequency range where whales communicate, 00:12:16.000 --> 00:12:19.000 the main source globally, on our planet, for the noise 00:12:19.000 --> 00:12:21.000 comes from human ships, 00:12:21.000 --> 00:12:24.000 thousands of human ships, distant, far away, 00:12:24.000 --> 00:12:26.000 just all aggregating. NOTE Paragraph 00:12:26.000 --> 00:12:29.000 The next slide will show what the impact this may have 00:12:29.000 --> 00:12:31.000 on the range at which whales can communicate. 00:12:31.000 --> 00:12:34.000 So here we have the loudness of a call at the whale. 00:12:34.000 --> 00:12:36.000 And as we get farther away, 00:12:36.000 --> 00:12:38.000 the sound gets fainter and fainter. 00:12:38.000 --> 00:12:41.000 Now in the pre-industrial ocean, as we were mentioning, 00:12:41.000 --> 00:12:43.000 this whale call could be easily detected. 00:12:43.000 --> 00:12:45.000 It's louder than noise 00:12:45.000 --> 00:12:47.000 at a range of a thousand kilometers. 00:12:47.000 --> 00:12:50.000 Let's now take that additional increase in noise 00:12:50.000 --> 00:12:52.000 that we saw comes from shipping. 00:12:52.000 --> 00:12:54.000 All of a sudden, the effective range of communication 00:12:54.000 --> 00:12:57.000 goes from a thousand kilometers to 10 kilometers. 00:12:57.000 --> 00:12:59.000 Now if this signal is used for males and females 00:12:59.000 --> 00:13:02.000 to find each other for mating and they're dispersed, 00:13:02.000 --> 00:13:04.000 imagine the impact this could have 00:13:04.000 --> 00:13:07.000 on the recovery of endangered populations. NOTE Paragraph 00:13:07.000 --> 00:13:09.000 Whales also have contact calls 00:13:09.000 --> 00:13:12.000 like I described for the dolphins. 00:13:12.000 --> 00:13:14.000 I'll play the sound of a contact call used 00:13:14.000 --> 00:13:16.000 by right whales to stay in touch. 00:13:16.000 --> 00:13:18.000 And this is the kind of call that is used by, 00:13:18.000 --> 00:13:20.000 say, right whale mothers and calves 00:13:20.000 --> 00:13:22.000 as they separate to come back again. 00:13:22.000 --> 00:13:24.000 Now imagine -- let's put the ship noise in the picture. 00:13:24.000 --> 00:13:26.000 What's a mother to do 00:13:26.000 --> 00:13:28.000 if the ship comes by and her calf isn't there? 00:13:28.000 --> 00:13:31.000 I'll describe a couple strategies. NOTE Paragraph 00:13:31.000 --> 00:13:33.000 One strategy is if your call's down here, 00:13:33.000 --> 00:13:35.000 and the noise is in this band, 00:13:35.000 --> 00:13:38.000 you could shift the frequency of your call out of the noise band 00:13:38.000 --> 00:13:40.000 and communicate better. 00:13:40.000 --> 00:13:43.000 Susan Parks of Penn State has actually studied this. 00:13:43.000 --> 00:13:46.000 She's looked in the Atlantic. Here's data from the South Atlantic. 00:13:46.000 --> 00:13:49.000 Here's a typical South Atlantic contact call from the '70s. 00:13:49.000 --> 00:13:52.000 Look what happened by 2000 to the average call. 00:13:52.000 --> 00:13:54.000 Same thing in the North Atlantic, 00:13:54.000 --> 00:13:56.000 in the '50s versus 2000. 00:13:56.000 --> 00:13:58.000 Over the last 50 years, 00:13:58.000 --> 00:14:00.000 as we've put more noise into the oceans, 00:14:00.000 --> 00:14:02.000 these whales have had to shift. 00:14:02.000 --> 00:14:04.000 It's as if the whole population had to shift 00:14:04.000 --> 00:14:07.000 from being basses to singing as a tenor. 00:14:07.000 --> 00:14:09.000 It's an amazing shift, induced by humans 00:14:09.000 --> 00:14:11.000 over this large scale, 00:14:11.000 --> 00:14:13.000 in both time and space. NOTE Paragraph 00:14:13.000 --> 00:14:15.000 And we now know that whales can compensate for noise 00:14:15.000 --> 00:14:18.000 by calling louder, like I did when that ship was playing, 00:14:18.000 --> 00:14:20.000 by waiting for silence 00:14:20.000 --> 00:14:23.000 and by shifting their call out of the noise band. 00:14:23.000 --> 00:14:25.000 Now there's probably costs to calling louder 00:14:25.000 --> 00:14:27.000 or shifting the frequency away from where you want to be, 00:14:27.000 --> 00:14:29.000 and there's probably lost opportunities. 00:14:29.000 --> 00:14:31.000 If we also have to wait for silence, 00:14:31.000 --> 00:14:34.000 they may miss a critical opportunity to communicate. 00:14:34.000 --> 00:14:36.000 So we have to be very concerned 00:14:36.000 --> 00:14:38.000 about when the noise in habitats 00:14:38.000 --> 00:14:40.000 degrades the habitat enough 00:14:40.000 --> 00:14:43.000 that the animals either have to pay too much to be able to communicate, 00:14:43.000 --> 00:14:45.000 or are not able to perform critical functions. 00:14:45.000 --> 00:14:48.000 It's a really important problem. NOTE Paragraph 00:14:48.000 --> 00:14:50.000 And I'm happy to say that there are several 00:14:50.000 --> 00:14:53.000 very promising developments in this area, 00:14:53.000 --> 00:14:56.000 looking at the impact of shipping on whales. 00:14:56.000 --> 00:14:58.000 In terms of the shipping noise, 00:14:58.000 --> 00:15:01.000 the International Maritime Organization of the United Nations 00:15:01.000 --> 00:15:04.000 has formed a group whose job is to establish 00:15:04.000 --> 00:15:06.000 guidelines for quieting ships, 00:15:06.000 --> 00:15:08.000 to tell the industry how you could quiet ships. 00:15:08.000 --> 00:15:10.000 And they've already found 00:15:10.000 --> 00:15:13.000 that by being more intelligent about better propeller design, 00:15:13.000 --> 00:15:16.000 you can reduce that noise by 90 percent. 00:15:16.000 --> 00:15:19.000 If you actually insulate and isolate 00:15:19.000 --> 00:15:21.000 the machinery of the ship from the hull, 00:15:21.000 --> 00:15:24.000 you can reduce that noise by 99 percent. 00:15:24.000 --> 00:15:27.000 So at this point, it's primarily an issue of cost and standards. 00:15:27.000 --> 00:15:29.000 If this group can establish standards, 00:15:29.000 --> 00:15:32.000 and if the shipbuilding industry adopts them for building new ships, 00:15:32.000 --> 00:15:34.000 we can now see a gradual decline 00:15:34.000 --> 00:15:36.000 in this potential problem. NOTE Paragraph 00:15:36.000 --> 00:15:39.000 But there's also another problem from ships that I'm illustrating here, 00:15:39.000 --> 00:15:41.000 and that's the problem of collision. 00:15:41.000 --> 00:15:44.000 This is a whale that just squeaked by 00:15:44.000 --> 00:15:47.000 a rapidly moving container ship and avoided collision. 00:15:47.000 --> 00:15:49.000 But collision is a serious problem. 00:15:49.000 --> 00:15:52.000 Endangered whales are killed every year by ship collision, 00:15:52.000 --> 00:15:55.000 and it's very important to try to reduce this. 00:15:55.000 --> 00:15:58.000 I'll discuss two very promising approaches. 00:15:58.000 --> 00:16:00.000 The first case comes from the Bay of Fundy. 00:16:00.000 --> 00:16:02.000 These black lines mark shipping lanes 00:16:02.000 --> 00:16:04.000 in and out of the Bay of Fundy. 00:16:04.000 --> 00:16:06.000 The colorized area 00:16:06.000 --> 00:16:09.000 shows the risk of collision for endangered right whales 00:16:09.000 --> 00:16:11.000 because of the ships moving in this lane. 00:16:11.000 --> 00:16:14.000 It turns out that this lane here 00:16:14.000 --> 00:16:17.000 goes right through a major feeding area of right whales in the summer time, 00:16:17.000 --> 00:16:20.000 and it makes an area of a significant risk of collision. 00:16:20.000 --> 00:16:22.000 Well, biologists 00:16:22.000 --> 00:16:24.000 who couldn't take no for an answer 00:16:24.000 --> 00:16:26.000 went to the International Maritime Organization 00:16:26.000 --> 00:16:28.000 and petitioned them to say, 00:16:28.000 --> 00:16:30.000 "Can't you move that lane? Those are just lines on the ground. 00:16:30.000 --> 00:16:32.000 Can't you move them over to a place 00:16:32.000 --> 00:16:34.000 where there's less of a risk?" 00:16:34.000 --> 00:16:36.000 And the International Maritime Organization responded very strongly, 00:16:36.000 --> 00:16:38.000 "These are the new lanes." 00:16:38.000 --> 00:16:40.000 The shipping lanes have been moved. 00:16:40.000 --> 00:16:43.000 And as you can see, the risk of collision is much lower. NOTE Paragraph 00:16:43.000 --> 00:16:45.000 So it's very promising, actually. 00:16:45.000 --> 00:16:47.000 We can be very creative about thinking 00:16:47.000 --> 00:16:49.000 of different ways to reduce these risks. 00:16:49.000 --> 00:16:51.000 Another action which was just taken independently 00:16:51.000 --> 00:16:54.000 by a shipping company itself 00:16:54.000 --> 00:16:57.000 was initiated because of concerns the shipping company had 00:16:57.000 --> 00:17:00.000 about greenhouse gas emissions with global warming. 00:17:00.000 --> 00:17:03.000 The Maersk Line looked at their competition 00:17:03.000 --> 00:17:06.000 and saw that everybody who is in shipping thinks time is money. 00:17:06.000 --> 00:17:08.000 They rush as fast as they can to get to their port. 00:17:08.000 --> 00:17:10.000 But then they often wait there. 00:17:10.000 --> 00:17:12.000 What Maersk did is they worked ways to slow down. 00:17:12.000 --> 00:17:15.000 They could slow down by about 50 percent. 00:17:15.000 --> 00:17:18.000 This reduced their fuel consumption by about 30 percent, 00:17:18.000 --> 00:17:20.000 which saved them money, 00:17:20.000 --> 00:17:23.000 and at the same time, it had a significant benefit for whales. 00:17:23.000 --> 00:17:26.000 It you slow down, you reduce the amount of noise you make 00:17:26.000 --> 00:17:28.000 and you reduce the risk of collision. NOTE Paragraph 00:17:28.000 --> 00:17:30.000 So to conclude, I'd just like to point out, 00:17:30.000 --> 00:17:32.000 you know, the whales live in 00:17:32.000 --> 00:17:34.000 an amazing acoustic environment. 00:17:34.000 --> 00:17:36.000 They've evolved over tens of millions of years 00:17:36.000 --> 00:17:38.000 to take advantage of this. 00:17:38.000 --> 00:17:41.000 And we need to be very attentive and vigilant 00:17:41.000 --> 00:17:43.000 to thinking about where things that we do 00:17:43.000 --> 00:17:45.000 may unintentionally prevent them 00:17:45.000 --> 00:17:48.000 from being able to achieve their important activities. 00:17:48.000 --> 00:17:50.000 At the same time, we need to be really creative 00:17:50.000 --> 00:17:53.000 in thinking of solutions to be able to help reduce these problems. 00:17:53.000 --> 00:17:55.000 I hope these examples have shown 00:17:55.000 --> 00:17:57.000 some of the different directions we can take 00:17:57.000 --> 00:17:59.000 in addition to protected areas 00:17:59.000 --> 00:18:02.000 to be able to keep the ocean safe for whales to be able to continue to communicate. NOTE Paragraph 00:18:02.000 --> 00:18:04.000 Thank you very much. NOTE Paragraph 00:18:04.000 --> 00:18:06.000 (Applause)