Old-time voice It was a late spring evening in 1942 when tests were completed and the night operators settled down for their first lonely vigil. Suddenly, red lights flared on the panel. Warning signals from those hydrophones in the bay.

Old-time voice What caused these strange sounds? No evidence of any unusual craft could be found, yet each evening the phenomenon occurred and soon became one of the most baffling mysteries of the war. The military turned to the scientists for help and at last the answer came with the clatter of the teletype. “Disregard unusual hydrophone signals; sounds made by schools of fish known as croakers.” Fish that talk.

Elin Kelsey How do they hear? Do they …

Ami Kingdon I don’t know how the fish hear. How do fish hear?

Kat Pyne Do fish hear? Do fish hear?

Elin Kelsey Well, they must if they are making these sounds. Right? But I’m, I’m trying to think about …

Ami Kingdon When I think of a fish, I don’t think of ears on a fish.

Elin Kelsey Yeah ’cause they don’t have those external pinnas do they?

Ami Kingdon No.

Elin Kelsey Like the parts that stick out of us? I don’t, I don’t think I’ve seen that on a fish, have I?

Kat Pyne That would look so weird on a fish. I can’t picture that.

Ami Kingdon That would be very weird on a fish.

Elin Kelsey Although I’ve seen many cartoon fish wearing sunglasses, which would require some sort of ear.

Ami Kingdon That’s a good point. We do need ears to wear sunglasses. I never thought of that before.

Elin Kelsey I think I understand that some fish grunt by, you know, constricting their swim bladders, right?

Ami Kingdon Yes.

Elin Kelsey So they’re not using their mouths. And I know for a long time, you know, it was very hard for us. If we see a beluga, those types of whales, to realize they’re not making a sound out of their mouth, they’re making a sound out of their blowhole, you know. So you see them with their open mouth and that’s where you put the little thought bubble, but that isn’t actually where the words come out.

Ami Kingdon Yeah. I mean, belugas have lips in their blowhole and then they hear with their jaws.

Elin Kelsey And there’s way more fish and way more marine invertebrates than there are mammals.

Ami Kingdon Absolutely …

Elin Kelsey So it’s, you know, really, we have a, minutely skewed idea about sound in hearing and noise and all of the things that we’re going to look at.

Christian Rutz My name is Christian Rutz, and I am professor of biology at the University of St Andrews in Scotland.

Christian Rutz We know that it is significant and it is an effect that was felt all around the world.

Christian Rutz Many of our members fitted these tracking devices onto their chosen study species before COVID-19, not knowing that this pandemic was about to unfold. And we realized that this is an absolute gold mine of data where we can look at animal movements and behavior from before, during, and after lockdown, and see how animals respond to the presence or absence of humans.

We’ve been offered data for almost 200 different species, so we are talking tens of thousands of animals that have been wearing these tiny tracking devices ranging from small songbirds to large whales.

Elin Kelsey And you are dealing with such a mountain of data—do you have a way of expressing the quantity of data that you have?

Christian Rutz The word that comes to mind is “mind-boggling.” It’s an avalanche of data.

I think it’s fair to say that I haven’t slept much over the past four months, I mean these people have pulled endless all-nighters to launch this project because of the pace at which this opportunity arose and needed to be grabbed.

John Calambokidis By late March, when things had dramatically shut down, it was a whole other experience launching and going out and spending time. First of all due to the COVID restrictions I was operating solo. I was just out in my boat alone since we didn’t want to have multiple people in the boat and the boat launches were closed, none of the whale watch operators were going out. It was really a feeling that harkened back to 30 years ago when traffic was less.

Getting a chance to see whales in situations that are what you’d have to call more pristine I think is always heartening, in that sense, of course you’re there so now you’re not quite as pristine because you’re out there, and I always want to be cognizant and recognize my own contribution and presence and not pretend that there was nothing else there. Of course I was there!

John Calambokidis Partly because there was this dramatic decrease in vessel traffic. One of our interests was to collect skin samples by biopsy to be able to look at stress hormone levels.

John Calambokidis Immediately after the 9/11 attacks, they collected a series of fecal samples from North Atlantic right whales that then revealed dramatically decreased levels of stress hormones.

John Calambokidis And that surprising study of decreased stress levels was partly why, in this current round, we were trying to think, Is this another opportunity to look at that?

Matt Pine Auckland’s our biggest city, where a third of the country lives, has one of the highest boat ownership rates of anywhere else in the world. There’s coming up to 200,000 boats. We’ve got this very busy metropolitan area right on the doorstep of an ecologically significant embayment.

We had hydrophones in the water before lockdown, and we were measuring up to 70 percent of a 24-hour period containing boat noise. As soon as sunrise came to sunset, we have almost continuous boat noise.

But unlike other parts of the world, we entered a complete lockdown on vessel traffic. It wasn’t voluntary; it was enforced.

Matt Pine So overnight, we’ve turned everything off.

Matt Pine We had a lot more people reporting marine mammals closer to shore, up rivers; we’re having animals where they don’t normally go because it is normally so noisy for them.

But what we are particularly interested in is the ability of bottlenose dolphins and common dolphins to communicate with one another in this much more quieter world.

During the lockdown, we were picking up dolphin whistles and call rates had increased, and that stuff, for far longer periods of time than we were before lockdown.

Right near the city, you can hear invertebrates crawling over the hydrophone, you can hear fish grunting, you can hear dolphins whistling, and waves crashing on a beach four kilometers away, and it’s just … it’s just, I’ve never heard an ocean without boats before.

This is an unprecedented opportunity because we can now have actual trends, correlations, and data that were just impossible to get before. I mean it cost billions of dollars; it’s the world’s most expensive experiment.

We won’t go back to how we were because now we know. One of the arguments I’ve always faced in the past is it’s all theory based—you think that would happen—but now, of course, we’ve got the actual numbers.

Matt Pine Yeah, everything, so from the zooplankton that use sound as orientation cues, to the fish that use them to avoid predators to find mates, to the marine mammals that use sound to eavesdrop on their prey and use vocalizations to maintain the group, to your whales that will sing and listen to their environment during their migration. So everything is linked to that soundscape, and all animals are impacted sort of across the board.

Ami Kingdon After the war, the navy kind of really upped their game in terms of trying to figure out, well, what fish make noises? How do they make noises? When? So they actually got a woman called Bobbie Fish. Very good name.

Kat Pyne That is so on point.

Elin Kelsey That was her real name?

Ami Kingdon That was her real name, Bobbie Fish. Not the wrestler. There’s a wrestler called Bobbie Fish right now. Who’s active. I just want to be clear! The US Navy did not send the wrestler Bobbie Fish. And she went up and down the east coast of the US and she recorded all of these fish sounds.

Helen Scales In December 1963, a woman with short curly hair sat behind the wheel of a gray Chevrolet sports wagon as she drove north from Rhode Island, along America’s eastern shore towards Maine.

The car was packed with gadgets. There were banks of waterproof microphones, spools of cables hundreds of meters long, two-way radios and walkie-talkies, battery packs and generators, a collapsible aquarium tank made of canvas, and an aluminum boat strapped to the roof. This was a fast-response mobile listening station, on a mission to find noisy fish. The driver’s name, it just so happened, was Marie Poland Fish. She was usually known as Bobbie.

John Calambokidis Then on the other hand we have the huge benefits that have come in from new technologies. Ten, 15 years ago, it was the advent of high capacity, remote recording packages that can record the sounds of whales for months and months at a time, 24 hours a day. But then some of the tagging technologies—I’ve now probably deployed suction-cup-attached tags on close to a thousand different whales along the US west coast of many species. Some of the tags we’re deploying are recording 12 different sensors recording hundreds of times a second. So you are getting this incredibly high-resolution data. Sometimes hours of video with it as well that give us insights into whale behavior that we never had before—how they feed, how they move, how they respond to human threats. So those have been really advantageous things.

Culum Brown I think research currently suggests around 50 percent or more of all fish species are communicating using sound. So it’s clearly a really important mode of communication for them. And probably people don’t realize that there are dawn and dusk choruses under water just as there are on land.

Culum Brown My name is professor Culum Brown, and I’m a professor at the Macquarie University campus in Sydney. And I’m head of the fish lab.

Elin Kelsey You say that with great enthusiasm. I’m glad to see that. So you’re a fish lover, clearly.

Culum Brown I am a fish lover, and I’m not terribly concerned about what fish they are, as long as they are fishy.

Sound production in fishes is extremely diverse. The mechanisms that they use is far more diverse than any other organisms. So it’s pretty cool and it’s grossly underestimated, I think generally by the public.

Elin Kelsey Culum, could you just talk me through them really quickly? I know you mentioned the swim bladders and the muscles and, what, what other ones I know they can fart, right. To make gassy sounds. Yup. What other sounds do they do?

Culum Brown They can also grind their teeth. They can make noises using, so in their gills they have gill rakers as well, which they can also grind. They can make noises by moving their jaws around. All sorts of weird and wonderful ways of making noises. So, yeah, swim bladder–related vibrations, whether it’s muscles or whatever else. So, yeah, the diversity is huge and really we’ve only come to appreciate that, I would say, in the last three or four years. And it’s such an untapped area of research that basically you could go and look at any fish in any context and whatever you discover it would be new.

Christopher Clark We now are recording, constantly documenting, more sounds that we do not know what they are than we know what they are. You dive into that universe of sounds, and yes, metaphorically you recognize some of the stars and the planets, but mostly you find yourself saying, “I’ve never heard this before. What on Earth is it?”

Shima Abadi Okay, I’m going to start with an easy one.

Elin Kelsey Oh no, now I’m nervous.

Elin Kelsey Okay, that I think is a whale sound. Is that right?

Shima Abadi That’s correct, it’s a humpback whale sound.

Elin Kelsey Okay, good, one for one.

Shima Abadi Okay, I’m gonna play this one.

Elin Kelsey Oh, can you give me a hint?

Shima Abadi It is a man-made noise.

Elin Kelsey Is it an engine, like a ship sound?

Shima Abadi Yes, it’s a ship noise. It’s a research vessel about 14 kilometers from the hydrophone. Okay, let’s play another one.

Elin Kelsey Okay, now that one to my ear sounds really a lot the same like the one I just heard. Is that also a ship sound?

Shima Abadi It is not. It’s rain, actually.

Ami Kingdon The way that rain makes sound is it creates a bubble in the ocean, the bubble oscillates and pops. If it’s a small bubble, it’s a high sound. And if it’s a big bubble, it’s a low sound. And so she’s like if you have big raindrops, they make a lower sound, but they also make a quieter sound because the, they create so much froth at the surface, especially if it’s windy that it did that sound can’t move through the water as well. And so you actually have like a dampening effect. Whereas if you have like a medium-sized rain on a very calm ocean, that’s going to be much louder because it’s going to come down and travel more through the water. And so there was this whole physics and this whole thing about raindrops on the ocean.

Isabelle Cote I would suggest that anybody goes snorkeling and just hold your breath with your ears underwater and really focus on what you hear, and it’s just such a noise-rich environment underwater when you really start listening.

Isabelle Cote So from the loudness of the sound that you can hear on a reef, particularly at night, you can deduce how much coral there is on the reef. So, we have basically a sound index to reef health. When you have a lot of coral, you tend to have a lot of what we call “architectural complexity.” You have lots of holes and crevices and lots of places for animals to hide, and that’s the relationship to sound. So the more habitat there is for those invertebrates, the more invertebrates there are, and the louder the sound the reef seems to be making.

Elin Kelsey Wow. And what kind of invertebrates are making the sounds and how do they do it?

Isabelle Cote Yeah, so the loudest ones, the loudest invertebrates on the reefs, are called snapping shrimps, and you very rarely see them. Actually, in my decades of working on reefs, I’ve never seen a snapping shrimp because they do tend to hide pretty deeply in the reef. The sound is a bit like when you pour milk in a bowl of Rice Krispies.

Isabelle Cote They are a kind of shrimp that has a huge claw. As the claw closes, the water sort of cavitates and the bubble collapses, and that makes essentially a bang sound that is extremely loud, I mean extremely loud at the scale of the small shrimp. But sort of scaled up, people have said that it’s as loud as a jet plane taking off.

Isabelle Cote So fish and invertebrates, marine fish and marine invertebrates, most of them spend the first part of their life cycle as little tiny larvae that float around, and eventually they have to settle somewhere. So they choose where to go. They have a certain amount of choice because most of these larvae, even though they’re just a few millimeters long, they do have swimming ability, and they do follow various cues to figure out where the best places to settle. And it turns out that sound is one of the cues that they use to decide to settle in one place rather than another one. So it’s a short distance cue—they probably use other things when they’re further away from their reef, they might use smell, for example, but as they get closer to a reef, sound kicks in and little larval fish can discriminate between the sound of a healthy reef and the sound of an unhealthy reef.

Elin Kelsey Yeah, that’s phenomenal. And can you tell me how those tiny larvae in general, if I’m thinking of something that’s only a few millimeters long, what aspect of their bodies is actually hearing?

Isabelle Cote Yeah, so they have inner ears, they have lateral lines. The lateral line is basically a pressure system and sound at the end of the day is a wave, right, and it causes pressure on the body of the fish, so they detect that in a way that we can’t really relate to because we don’t have that means of hearing, that whole body hearing.

Elin Kelsey Wow. Whole body hearing.

Isabelle Cote If you stood against a big speaker that’s very loud, you feel like you’re hearing with your whole body as opposed to just your ears, right, you can feel everything inside, especially the air pockets, your lungs and so on, you can feel the vibration. That’s my approximation maybe of what it feels like, I don’t know. I know when I run in the forest, in the spring, I often hear grouse, which is a low sound. But interestingly, I literally, I feel the grouse more than I can hear the grouse.

Elin Kelsey Yeah, I know what you mean. It’s that deep drumming and you feel the percussiveness of it.

Isabelle Cote Yeah, except in this case, things like snapping shrimp produce very high frequency sounds as opposed to low frequency sounds. I don’t think I can explain; I definitely can’t relate to the whole body hearing of high frequency sounds.

Elin Kelsey Well, if you could relate to tiny, couple of millimeters zooplankton, that would be really, really impressive.

Isabelle Cote Like most other places in the Caribbean, about a dozen years ago or so, the Bahamian reefs were invaded by lionfish from the Indo-Pacific. And these are beautiful fish, but they are predators, and they eat a lot of very small fish. It got me thinking about the possibility that lionfish were altering the soundscape of reefs because, you know, they’re eating the sound-producing animals. So for several years, we’ve kept the number of lionfish really low on some reefs and on other reefs we hadn’t controlled them, so the numbers were higher. I didn’t realize at the time that most of this work was gonna be basically between 10 p.m. and three in the morning. And it was fascinating for what we ended up finding as well, which was that the reefs with a lot of lionfish were much quieter than the reefs without a lot of lionfish.

Elin Kelsey That’s amazing.

Isabelle Cote It’s kind of a double whammy effect. They’re eating the fish and they’re also making the reef quieter, so there’s fewer little fish coming in to replace the ones being eaten. That might be partly, just a small part of the explanation for why they’ve had such a drastic effect on some reefs.

Francis Juanes So we know on coral reefs that if we play back the sound of a healthy coral reef in a degraded one, fish will come. They will settle onto that reef and begin the process of recovering that reef. And so again, that’s a very unique experiment in one location, but it suggests that sound could be used to, to make environments healthier.

Elin Kelsey Well, my lovelies, I think we should get a drink or a bite to eat or something.

Kat Pyne I’m starving. Where should we go?

Elin Kelsey You know but I do hear, like down around the corner it sounds like there’s some people having a good time. I just finished teaching a class so I could really enjoy that.

John Ford In the case of killer whales the detection of a chinook salmon in the distance acoustically with their sonar, we’ve calculated or estimated that they might detect a salmon with their echolocation, maybe at about 100 meters range in quiet conditions.

John Ford I think that they are so acoustically sophisticated and capable that when they come into an area and they’re using their social calls—their dialects to keep in touch and so on, or even their sonar clicks—that these all have a pattern of reverberation that is unique to a particular place, and I really believe this plays a huge role in the animals use of their habitat and recognition of where they are, their orientation, and it is by these multitude of, sort of, I guess, passive feedbacks they get from their acoustic environment.

Daniel Kish I was born with retinoblastoma, which is cancer of the eyes. My eyes were removed by about the time I was a year old. By about the age of 15 to 18 months, I began clicking—or so I’m told. That click allows me, as a blind person, to see.

Daniel Kish Recent brain scans of myself and some people I’ve worked with have shown that when you learn this technique it is the visual brain that is processing the sound. So, it’s not just what we hear, it is what we see in our brain. That was a revolutionary finding to brain science.

Ami Kingdon Well, the first thing about Cook Inlet that you notice, that is very striking even above the water is that it is completely opaque. The water basically looks like a latte or like chocolate milk. The inlet is completely surrounded by this mountain range and all these streams are running off the mountains, all the time eroding away the land. We talk about how sound is very important underwater because vision is limited. Here, it’s not even a factor.

Ami Kingdon Cook Inlet has one of the highest tides in the world. Imagine that you’ve got this incredibly cold, very opaque and dark water, and the depth of it changes but you’re a beluga and you eat salmon and those salmon are coming out of all these stream mouths all along the edge of the inlet. So, you’re playing this game of timing, the whole time. And all of these creeks are rimmed by these sucking, spreading mudflats. And if you’re a beluga and you’re up there and the water drops, and you don’t know exactly what channel to swim out on, you’re going to get stranded and that actually happens a lot up there.

Ami Kingdon And they are so good at finding their way around this inlet, they were constantly using that high pitched sound to sense the depth and they were constantly using—I’m not even sure what sense, honestly—to judge when the tides changed. And as they are swimming up there they are using their sonar to hunt for food that’s coming out and watch for branches and stuff that’s tumbling around.

Ami Kingdon They make a lot of sounds above the water with their blowholes. They actually have little structures in their blowholes like we have in our throats and they are called phonic lips. They can make an insane array of sounds. I mean, it sounded like somebody throwing something down a culvert or some cats fighting and like a trombone. So, while I am listening to this ridiculous playful cacophony above the water, underwater you can hear a whole different range of sounds that they are making: the clicks and the buzzes and the whistles that are these high-pitched wayfinding sounds.

Ami Kingdon One of the most amazing things I’ve ever seen, in all of my time reporting, was what happened when—we were kind of getting towards the end of this whole stakeout, if you will; the tide was going to start rising again. We looked it up on our sophisticated tide tables that NOAA puts out. And so we knew that the tide was going to change at, I believe it was 6:43 that day, and all of a sudden, all the belugas, suddenly just started to swim away. And the researcher I was with says, “I betcha the tide just changed.” And so I pulled out my iPhone and I looked at the clock and it was to the minute, to the minute that the tide changed, that these belugas had sensed this.

Kieran Cox It’s a very low, like a hmmmmm. These calls can last for hours and the humming will go all night.

Kieran Cox And so it wasn’t until the ’80s when people were complaining about all this humming that was showing up at their houseboats and was it the navy or was it …

Amy Kingdon It’s weird, it’s not a human, a quibble …

Elin Kelsey And those muscles that they have around their swim bladder that’s, that’s so that they can expand … surface and sink?

Ami Kingdon It’s actually to make noise.

Elin Kelsey So it’s acoustic, on purpose?

Ami Kingdon It’s like vocal cords. Yeah.

Elin Kelsey Wow. Yeah. But it’s in their bodies. It’s not anywhere near their throats.

Ami Kingdon No, it’s like, if you could make your stomach rumble a little bit on command.

Elin Kelsey As a pickup line.

Ami Kingdon As a pickup line, but you know, I’m sure there’s people that are into that. I know it’s one of those things that you hope doesn’t happen when you’re trying to pick people up.

Elin Kelsey Wow. So sound is hugely important to fish.

Ami Kingdon Hugely important.

Kat Pyne You know, and if at first your pickup line does not succeed, you have to remember, there’s plenty of fish in the sea.

Robert McCauley The fish choruses we record can be really amazing. You see some really strange things. For example, we did a trip down the west Australian coast, the middle of last year 2020, and we were deploying sonar buoys along the way every four hours. We passed a part of the coast, the Abrolhos Islands, and we had two fish choruses distinctly different, they were spatially separated. And then both of the choruses appeared to go around in big circles. I haven’t analyzed it properly, but it suggests either the fish school was moving, but it would have to have been moving quite rapidly to get the arcs we saw, or the sound was traveling through the fish chorus in a wave, like a Mexican wave in a stadium type thing. It just went around. So we just continually see phenomena like that which has never been reported before so it’s really, really interesting.

Elin Kelsey So I wonder right now during this anthropause where things are so much quieter because of COVID, less shipping, less everything. I wonder if it’s like a real bumper year for fish breeding.

Ami Kingdon I bet it probably is. Well, if you think about it, like you’re in a crowded bar and you’re trying to like, you know, sing your ballad to your lady friend over there in the corner, you know, your voice is going to carry a lot better if everyone’s a little bit quieter. So she’s going to hear you a lot better.

Elin Kelsey Wow.

Kat Pyne Otherwise you’re trying to yell across the bar. You look hot, what’s your number?

Francis Juanes It’s called the cocktail party effect or the Lombard Effect that humans experience, in the days when we used to go to loud parties, that you find yourself talking louder in order to be heard. So fish do this, marine mammals do this, and they sometimes can speak at a different frequency so that their sound can be noticed by their conspecifics.

Francis Juanes So our most recent work is on a really wonderful species called the midshipman fish. This is a deep-sea fish that comes up into the intertidal on all our beaches in BC and a male builds a nest under a rock and starts humming this very particular call that it has …

[MIDSHIPMAN HUM]

and it uses this hum to attract females. And so we’ve done this experiment where we had artificial noise and showed that the male had to call louder and a different frequency. And we’re following up with experiments to see what the long-term effects of noise are because the male sits in the nest for a couple of months at a time and doesn’t feed for all that time. And so we think that noise is going to have a really important effect on this species.

Elin Kelsey Yeah. And that’s a sound that I bet a lot of people listening know, even though they might not realize it. That incredible humming sound. If you’ve been lucky enough to sleep on a boat, you know, along our coast, in the breeding season.

Francis Juanes Right. And it happens at a frequency that is quite low, but it’s the same frequency that a lot of the ship noise occurs at. So, there’s a potential for masking to be particularly important as well.

Kieran Cox Yeah, oh yeah, biting, you know stabbing with spines, like essentially wrestling—it’s a very brutal encounter.

Kieran Cox You’re this midshipman, April has hit, you enter the intertidal. You need to find a location that is going to be suitable for you. This should be a place where there’s going to be some sort of rocky outcrop where you can dig a burrow essentially and establish a good nest that you can defend. You then have to dig it, clean it all out, set yourself into this place, and then you have to defend it.

So I am sitting in my nest and I’m basically yelling, “I’m a great guy,” “I’ll look after your young,” “This is a great habitat,” “You should certainly come here,” “Don’t listen to those other guys,” “This is where you want to be.”

Kieran Cox You have 400 eggs and you have to try to ensure that the maximum number of your potential offspring make it. So how do you do it? Right if you put them all in one nest, even if it’s a great male and the acoustics were incredible, what if he gets eaten by an eagle the next day? But if you could span that out and you give the top 10 males all some eggs, right, or you gave them out at different times, you can set up this scenario in which location, acoustics, male quality, all of these things are interacting and females being choosey is you know, to the better of the species.

Jordan Raine Historical accounts indicate that soldiers have roared in battle throughout history all the way through from the Roman army to the Red Army, we see it in various sports, whether it’s the New Zealand rugby team’s haka, or in wrestling. And also the US National Park Service even recommends roaring as a defense strategy against bears.

Jordan Raine And under these conditions, we found that listeners are actually really good at judging strength and height from the voice.

Erica Escajeda Unless you find a very, very loud example and then you have to have over-the-ear headphones turned up and then it just, it feels kind of like a, it was more like a feeling of vibration, and I call it a purr almost, ’cause that’s what it sounds like, a really deep purr.

Erica Escajeda Because we’re so familiar with humpbacks, we think of these really intricate songs with different phrasings in there, but with fin whales it is very simple, it’s just “pulse, pulse, pulse, rest, pulse, pulse, pulse.” And those have actually been determined to be songs.

Erica Escajeda It’s kind of a lot like watching static TV. You see a lot of static, which is the background noise, but occasionally you’ll see a little, a little blip or, in the case of the fin whales, swoops and little squiggly lines, and then I’ll stop and listen to that, and I realize, oh, that has a humpback whale moan or, that’s a fin whale pulse or a gray whale moan. So, you come to recognize the shapes that you see visually as the calls. So luckily that, even though I can’t hear fin whale calls very well, I can see them very clearly.

There’s been recent research to show that blue whales in particular can change the frequency of their calls. In fact, we’ve been seeing lower frequency calls in recent years.

Erica Escajeda And so when they were evolving and they settled on this low frequency behavior, there’s nothing else in the ocean that was making sounds at that frequency band. It was an acoustic niche, if you will, that was completely open to them. However, now with shipping, a ship noise, a lot of ship noise, is in that exact frequency band that they use to communicate, and so perhaps the whales are responding to that increase in lower frequency noise and then thus lowering that frequency of their calls.

Erica Escajeda Another theory for why they’re changing their frequency is that these whales are recovering from overharvest due to commercial whaling, so perhaps there’s more competition, now there is more of them, and they have to distinguish themselves somehow and lower the frequency of their calls in response.

Erica Escajeda Under ideal propagation conditions in the ocean, blue and fin whales can be heard across like 1,300 kilometers in an ocean basin, so it could be as short as maybe 56 kilometers depending on where you are to as long as like 1,000 kilometers. And so, depending on if those whale calls somehow enter what’s known as the SOFAR channel, then those calls can potentially travel across the entire ocean basins easily.

John Calambokidis You know, blue whales produce one of the loudest sounds of any animal and it can travel for tens—and in the right circumstance—hundreds or thousands of miles.

The main fundamental frequency is below our hearing. It was still—the upper harmonics would sound really low to us—were still loud enough to knock my socks off. Listening for whales or hearing whales has always been a really thrilling part of my work.

Erica Escajeda One of the things I’m really interested in studying is kind of the onset of singing and when does it start in relation to the breeding season. Unfortunately, we don’t really know much about fin whale breeding behavior. We don’t know where they breed, when they breed. There are some hypotheses that they perhaps breed as they’re migrating south or even in the feeding grounds and then start migrating. But we don’t know for sure.

To our knowledge, we have no evidence to show that females make any sounds, which is really interesting to me.

Matt Pine Well, ones that have been described are mostly grunts, and grunts are quite sort of literally what they sound like, it’s like a grunt.

And a knock is just like a knock, like if you knock on a door or something like that is very short, it’s a bang bang bang.

Ami Kingdon Like a [knock sound] kind of noise?

Matt Pine Yeah, exactly, yeah. That kind of knocking sound. Yeah, and a grunt is just like … kinda growl literally like a grunt and I mean they’re not particularly loud, that’s the thing that was interesting to learn is these fish are quite cryptic in the sound production.

Matt Pine Seals are pretty good at eavesdropping on their prey, so as soon as a fish makes a sound, its location is now known. So, it’s not really in their advantage to make too many sounds in terms of being picked off by hungry ringed seals, but when it comes time to breeding, the trade-off between passing your genes on versus being eaten is good enough for them to risk it.

Matt Pine Yeah, that’s sort of our main sort of concern at the moment is what does 2050 have in store? I say 2050 because by 2050, the models are predicting that in the summertime, that Northwest Passage, that area of water between sort of eastern Canada all the way up over the top past Alaska and the Chukchi into the Pacific, will be ice-free in the summertime, so now we’ll be able to send ships and freight right over the top of the Americas instead of either through the Middle East or South or Central America through the Panama Canal, which is obviously hugely advantageous economic-wise, but what that means is the soundscape is going to change quite drastically in the next coming, you know, couple of decades.

Matt Pine Up in the North, it’s sort of that last untouched area. You know it’s still very quiet, it’s probably some of the quietest waters in the world.

Matt Pine Essentially all species, in some way or another, some shape or form, depend on sound at some stages during their life, because it is that one cue that travels in all directions over hundreds of kilometers with minimal attenuation, unlike light and smell and vibrations, that now we’re starting to be concerned about the changes to a soundscape.

From the zooplankton that use sound as orientation cues to the fish that use them to avoid predators to find mates, to the marine mammals that use sound to eavesdrop on their prey and use vocalizations to maintain their group when they navigate, everything is linked to that soundscape.

John Ford Whales are among the very few mammals that have the ability to learn sounds that they hear in their environment and to reproduce them.

And so that ability of the animals kind of opens the door to, I think, more advanced ways of using sound underwater to keep in touch over long distances, to have a family badge that indicates who that animal is because it’s learned the particular sounds from its mother and its close kin. And by learning that, they acquire and keep that dialect, it seems, for their lifetime.

Elin Kelsey I know John, when I first knew you, your ability to hear those different dialects was so attuned that in the early days, you were much stronger than a computer. Is that still true?

John Ford So, well, my ears aren’t what … My ears aren’t what they used to be, unfortunately, because too many years in noisy boats has damaged my hearing, and I can’t quite hear those high frequencies like I used to, but I’m working with some very talented young colleagues and students who have really good hearing and it’s a bit depressing when they’ll bring something up on the computer screen and say, “Hey, listen to this, will you,” and I put the headphones on and hear nothing! So I say, “Well, could you turn it up a little bit?”

John Ford It’s somewhat like learning a human language, I think, in that there’s a lot of nuances in the sounds that are important to be able to make those identifications of what’s actually being said or being called by the whales.

Elin Kelsey You’re a very unique person in the sense that you have a 40-year fluency listening to a specific population. Are there things that you’re constantly listening for now that you weren’t before … as your fluency has increased and your understanding because of that fluency?

John Ford Well, what I’m really curious about is why these family-specific repertoires of calls are so persistent. They made recordings back in the early 1950s of killer whales. They had no idea who or what type—of course we didn’t know anything about them in those days—but they sound just basically the same as they do today. This one recording …

John Ford For females in a matrifocal society like the resident killer whales, they’re the dominant animals, and so anybody in her group is not very likely to change the dialect because she’s the matriarch. Granny is still making those sounds. And so I think we need to look at killer whale dialects in terms of cultural generations in a way, rather than biological generations, which might be only 20, 25 years, but a cultural generation would be the time period that a matriarch would have social influence and dominance over her group, and perhaps when she dies, maybe they’ll be some sort of accelerated change in the dialect, but so far, most of the key calls sound just the same today as they did back then.

John Ford But within the resident form, they are very unusual animals in many respects because they kind of break a lot of the social rules. As far as we’ve seen in 45, almost 50 years of monitoring the population here on the west coast, no individuals have ever been seen to leave the group into which they were born and join another group. Which raises the question: how do they prevent inbreeding?

John Ford Males will mate with females or females will accept mating males from outside the kin group. It’s likely that the dialect serves as an outbreeding mechanism. So whales might be attracted to mating partners that have a foreign accent if you like.

John Ford So it’s kind of an amazing system that is, I think, without precedent. It’s taken many decades to really unravel.

John Ford When it became apparent over the early years of this work that these were essentially acoustic cultures—culture being behavioral traditions that are passed on across generations by learning—then it became a little tricky again because as soon as you start talking about nonhuman cultures, some people don’t really accept that.

John Ford And I was emboldened to do that because the bird scientists, people studying bird song, were using those terms. And nobody really raised an eyebrow, but as soon as it was with another mammal, then there was more scrutiny. And now, of course, through a lot of efforts by some of my esteemed colleagues, like Hal Whitehead for example, has really been the leading champion of showing the importance of culture in the lives of cetaceans. He studies sperm whales primarily and they are very cultural in what they do. And there’s been a real increase in interest and awareness in recent years of the importance of culture in conservation. A lot of reliance is placed on traditional knowledge that is passed on across generations, or within, laterally, among different populations and it’s really important to preserve these cultures.

Elin Kelsey All of these sounds are made by the same ocean animal.

Isabelle Cote You will not believe what walruses sound like underwater!

Isabelle Cote My project was supposed to be, to look at whether you could identify individuals from their vocalizations. It’s a series of knocks like [she knocks on desk] and then they strum like [dring!] like a guitar and they make a bell sound. I could recognize individuals and that there were regional dialects. I got recordings from two or three places in the Arctic and they sounded different.

Christopher Clark To build that image, Katy and Roger had to use a machine that would produce a picture on a piece of paper that showed just a two-and-a-half second voiceprint. They made hundreds of these individual pieces of paper and taped them together into long strips and put these strips in rows, one above the other up on the side of their barn, and when they stood back and looked, voila. They could see the pattens they were hearing when they listened. They could see the song as a musical pattern.

Katy Payne But if you keep listening for months on end, and then for years on end, you discover that the song—each facet of it—is continually evolving to something slightly different. And all the whales in the ocean—or in that singing population—are changing their song in the same way. So that was something I discovered, and at the end of the day, I had studied 32 years’ worth of songs, many of them in two different populations.

Janie Wray It’s pretty amazing to listen to a humpback whale compose a song. One whale will start up, maybe with just a simple up-down swooping-like call, he’s really just practicing at first, changing one bit or another. But then another whale will pipe in. And that whale may add just a soft “woop,” but then the timing changes. Two or three whales may do this together like musicians jamming, and it can all sound really random at first, but then suddenly it evolves into this long beautiful song that can truly melt your heart.

John Calambokidis As those whales return to the Salish Sea, they not only started returning every year, but mothers with their calves that were born there, those calves would be returning themselves. So you saw not only the rediscovery of this area, but then how that transmission, culturally if you will, you know, from mother to offspring, or from year to year with individual whales, then resulted in whales coming back, returning to those waters and now becoming a more loyal group of animals.

Culum Brown She’d been studying cavefish from Mexico, looking at the sounds that cavefish made. And she was able to record their sound and their behavior simultaneously. And she showed this amazing repertoire of sounds that they were making in all these different contexts. It was really incredible.

Culum Brown The biggest problem is that fish are in water…

Elin Kelsey And we’re not!

Culum Brown They’re in water, in a cave in the dark, which makes it even more difficult. But hats off to this student, I mean, she got infrared cameras, got all of the gear, abseiled into some of these caves, and set up experiments in the caves. This is in addition to the stuff she had done in the labs. I mean, that’s just …

Elin Kelsey … raising the bar for the rest of the scientists out there. That’s amazing.

Carole Hyacinthe You also may want to train a little bit before going, like in a gymnasium or something. The one I did, which was impressive to me was the Marino Cave because if my memory is correct, it was a 68-meter straight pit to go down on a single rope, then you have to think that you also want to go up at the end of your experiment, right?

Elin Kelsey Right!

Carole Hyacinthe When I don’t have the sound, it’s like watching a movie, understanding half of the story, a part of the story, but not the entire story of what is happening.

Carole Hyacinthe There are striking differences between the behavior of those fish. The differences that we see may be in part also related to the different habitats in which one, the fish lives, their environment may be related to their behavior in some way. And this behavior then will influence the sound production. And this is why we really think that if not an evolution of the sound itself, maybe an evolution of the use of the sound, in fact, between the two morpho types.

Culum Brown And she found that some of the noises that were used in one context for the surface fishes were used for a completely different context in the cave-dwelling species, or they’re really subspecies. So that, that’s really amazing. I mean, not only is there diversity within species, but depending on whether they’re living in caves or whether they’re living on the surface, they change the noise that they’re using. It’s really cool.

Elin Kelsey Does that start to get us closer to cultural difference?

Culum Brown It certainly speaks to the possibility that there’s some kind of cultural differences. But I think it’d be fair to say that as far as I’m aware, nobody has ever looked at cultural differences in sound production, but frankly, I’d be shocked if it wasn’t happening.

Elin Kelsey Is that because of your awareness of cultural traditions in ways other than sound?

Culum Brown Yeah, that’s right. I mean, we’ve known about culture and fishes, gosh, for a really long time now, probably 30 years almost, perhaps even longer. But I think we’ve increasingly realized how important culture can be. There are lots of contexts related to movement and migration, spawning grounds, feeding grounds, and, and all these sorts of things that are culturally inherited in fishes.

But I suspect that we’ll discover sooner rather than later, that culture is, is happening in a sound context as well. I think that we’re so early in our investigations that it hasn’t happened yet.

Christine Gabrielle So we have this hydrophone that’s anchored on the bottom of the ocean. So that’s an underwater microphone basically, has a five mile cable, runs all the way to a computer in my office here. And so I have a little speaker where I can listen to what’s going on in the ocean at any moment.

Christine Gabrielle There are whales, you know, vocalizing back and forth. And it was just like this, you know, auditory scene that I feel really lucky to have been able to hear.

If there had been boat noise in the background, I would have a very low chance of being able to hear that.

John Calambokidis We were doing a study looking at how blue whales respond to navy sonar. And we had deployed these suction cup attached tags on this blue whale off LA Long Beach. And while we were tracking it to do this other study, this ship comes through and goes right over the top of the blue whale. And we thought it was going to hit it. And we realized, Whoa, this is pretty crazy, what happened here?

And in tens of meters of distance from the ship, it dove down below the hull of the ship and was missed being hit by this really small distance by this change in diving behavior.

John Calambokidis You know one whale we had a tag on for 10 days to look at fine-scale movements and it had 14 near misses with ships in that 10-day period. That whale with the 14 encounters was actually off of San Francisco Bay and there are three different shipping lanes that come into San Francisco Bay and it turned out that this whale was actually feeding moving around in all three of the lanes.

Ami Kingdon Like there are superhighways of ships; they’re coming and going all the time. And you just think like, those whales are living beside a highway.

Ami Kingdon I don’t know about you—

Elin Kelsey But we’re in the middle of it in the case of the west, having around those shipping lanes.

Ami Kingdon Like if you buy a house and there’s a highway right outside, that’s generally considered a negative thing, right? Mostly because of the noise. And so you gotta think, like we just built an 18-lane expressway, two actually, because there’s two ports I think right beside each other, and that’s the main conduit for, you know, stuff coming in from, from Asia, from China, from Japan, from Korea, from Southeast Asia, all of that trans-Pacific stuff.

John Calambokidis Slowing down ships is sort of this impressive thing because it reduces the lethality of ship strikes, it dramatically reduces fuel usage, it reduces the amount of air emissions of pollutants, and it reduces the sound production. So it’s kind of like a win on four different fronts.

Francis Juanes The Port of Vancouver has had a very successful program, asking ships to slow down on their approach to the port and it’s led to really, really reduce levels of noise. So we know that that can happen.

Francis Juanes But, you know, it’s expensive. And so I’m sure that shipbuilders are not happy to do that immediately, but, but I see that as, as what will happen in the future, particularly if there’s legislation that requires them to do that.

There are quieter ways to do marine construction as well. There are ways to build bubble sheets, for example, so that the noise doesn’t travel as far as it might otherwise. There are ways to, to drill more quietly. So the technologies are there.

Isabelle Cote So we have this experiment where we’ve been watching cleaner fish for 20 minutes, and then we sent up a signal and then a boat came zooming over us for 20 minutes, and we found that that increased the amount of aggression that was going on between the cleaner fish and its clients. So fish go back to their normal behavior pretty quickly, but that again raised a bunch of questions about, well, what happens when these fish are in an area where there’s continuous, continuous background sound like that? Do they habituate or do they end up sort of being hyper-aggressive all the time? What effects ultimately, does that have on the fish sort of longer term?

Ami Kingdon Is that the loudest thing that we make in the ocean, seismic airguns? Or are there other sounds that we make that are … I would imagine some ships get pretty loud.

Elin Kelsey I think it’s it, it’s one of those cases I think where ship traffic is, is the most chronic noise problem but the loudest noise are these seismic airguns.

Kat Pyne So how does that actually affect the animals themselves? Like does that mean, we know they have, fish have ears now. I mean, does that blow out their ears? I mean, does that hurt them or does it just disrupt their ability to communicate with each other?

Kat Pyne “The most obvious sign of trouble came when masses of dead beaked whales started showing up on beaches. Loud sounds seem to trigger panic dives that cause a kind of decompression sickness in the cetaceans, and hemorrhages in their brains and hearts. In the five decades before 1950, researchers recorded just seven mass strandings. But from then to 2004, after the introduction of high-power sonar for naval operations, there were more than 120. Studies show that exposure to loud noises can damage ears and cause hearing loss in cetaceans.”

Jayson Semmens I’m Professor Jayson Semmens. I’m a research scientist at the Institute for Marine and Antarctic Studies in Hobart, Tasmania, Australia.

Airguns are what the petroleum oil and gas industry use for looking at the deposits in the Earth’s crust seafloor.

Elin Kelsey From that standpoint, it sounds, you know, Oh, that’s very logical. Like what a good thing. It’s not introducing any foreign substances, it’s just using air, but it’s really it’s the volume of the sound, is that right?

Jayson Semmens Yes. So it can get over 200 decibels. It’s high levels of sound.

Elin Kelsey And when you’re saying 200 decibels for people who don’t know how loud that is, is there a familiar comparison you might use?

Jayson Semmens Uh, I guess I think you’re a jumbo jet taking off nearby.

Jayson Semmens The general understanding was that you could get plankton killed within a few meters of an airgun, but beyond that, nothing. And we showed that there was a large increase in mortality—a change in abundance—up to a kilometer away from the airgun.

Jayson Semmens The sorts of research we’re doing are relatively new. There’s been lots of work on what’s the impact on whales and dolphins and seals, the marine mammals, but those animals you don’t see, invertebrates, those animals sitting on the bottom, that play an incredibly important role in the food chain, in the ecosystem, and often are animals that can’t move out of the way, unlike you know whales and dolphins and these sorts of things.

Jayson Semmens It’s very dangerous getting close to it and as soon as you get close to them they’ll be on the radio saying you need to move back. And they have ships that are working with them, clearing people out of the way because they just can’t stop, you know, once they start they just can’t stop. It’s tricky. And then you’ve got, you know, different weather conditions to deal with. It’s, it’s really difficult to do.

Jayson Semmens We had three months of looking after these octopuses, feeding them, caring for them, all that. There’s no, no time off. It’s just constant. And with that many animals and then their offspring as well, halfway through was thinking, Why on Earth did I come up with this idea? It seemed like a great idea at the time, but man, it was a lot of work.

Jayson Semmens What does it mean? Not on the individual level, but the population level. Will they still reproduce enough offspring to keep the population going? Those sorts of questions are still really unsolved.

Jayson Semmens So if you’re a lobster, the only way you know what way’s up and can balance on your legs properly is because of this organ. And so the work we did with the lobsters, we showed that the seismic signal was, was shearing off these hair cells.

So when you turned a lobster on its back, if it was exposed to seismic signals, it took longer to get itself off its back than an animal that wasn’t.

Jayson Semmens And it was a real shock: what is going on here? And so what we proposed is that those animals are exposed to noise, not seismic, but, you know, vessel noise, and various other things. And you know this was a real surprise.

Christine Gabrielle I admit that it sounds a little bleak when you think about whales having less room to communicate. But, you know, the reality is that, globally, animals are contending with humans all over the place, including the sound environment. And sometimes the, it’s the wind or the rain that’s creating that noise. So, they’re evolved, you know, to be able to, to adapt to things. However, they’ve only had to contend with vessel traffic as you know human noise, for about 200 years. So they’re still, you know, probably getting the hang of it. But they do kind of the same kind of things … they seem to do the same kinds of things that you or I would do if we were trying to communicate and it was noisy in that maybe they would get closer together, maybe they would talk louder, maybe they would repeat themselves. They, the whales, seem to do all of these same kinds of things that we do, but it’s something that we really want to understand better. The study that we’re planning to do with my colleague Michelle Forney, who’s now at Cornell University, we are going to try to look at whether the repertoire and the patterns of vocalizations that the whales use during this quiet period are, are fundamentally different from what they did in other years.

Francis Juanes I do feel hopeful, I do very much feel hopeful the next set of work that I think will be very inspiring is the results that are coming out due to the lockdown. So we will show, and lots of people will show, that shipping went down for—and all sorts of other noise sources—stopped essentially for six weeks. And so now we’re starting to see what the results of that was. We saw animals where they’d never been before, their ability to communicate increased, and the levels of noise went down by a lot. I mean in, at levels that we’ve never seen before, there’s never been an experiment like that since 9/11. And so except this one was, was much longer in nature. So I think that’ll be another thing that will captivate the public’s attention, I hope.

Spencer Greening My name is La’goot. That’s my Tsimshian name. I come from the community of Hartley Bay, the Gitga’at First Nation, which is its Tsimshian community. And I come from the Raven clan, the Raven lineage, and my English name is Spencer Greening.

I’m an anthropologist and sometimes people refer to me as a Gitga’at scholar.

Spencer Greening Sound is something that can be forgotten in the modern era. And I’m, I’m truly grateful that I’ve been taught what I would call, I guess, protocols around sound by some of my elders.

I’ve heard it plenty of times up and down the coast—while harvesting, setting a net for fish, or setting branches for herring eggs—a lot of the old people, not only in my village, but like I say, up and down the coast, talk about the importance of doing it as quiet as possible.

I mean there’s definitely reasons for it, I think, and there’s this mix of reasons, too. Sometimes it’s spiritual, and sometimes it might be because doing that will attract more fish or have a more successful harvest.

When it comes to the spiritual aspect of silence, there are countless places in our territory where we have these agreements with what we call naxnox, which are these mystical beings or spiritual beings who often live underwater, but they can take the form of an array of things. Sometimes they can look like a sea monster, sometimes they can look like a thing of the wildest imagination that lives in the mountains. But in particular, these beings, we have these agreements in sort of treaties with them of when we’re in their territory, we have to respect sound. And when we don’t respect sound, then bad things will happen, though. The weather in that area can turn, the tides can go sort of haywire. The way the wind comes will be shifted and redirected and, and, and things will sort of go out of tune, so to speak. And so that’s one example that sort of brings us into this conversation of what these treaties can look like.

And it’s interesting on top of silence, there’s also an importance in making sound sometimes. And so it’s not just this one-sided piece of like nature in its essence is quiet, but nature in its essence has silence and noise. And there’s a way to understand both of those things that live in congruence with the laws that we’ve formalized as Indigenous people on these territories. And so I think of songs becoming a part of that sound, that noise, so to speak of the landscape that it, you know, sometimes places you’re supposed to sing before something happens. When we harvest cedar bark, often you’re supposed to speak to that plant first and you take up space in that sound space, but there’s this respectful way of doing it.

I think it’s worth, I guess, expanding our minds on this idea of good sound.

Maybe we won’t ever know it, but the fact that we can explore it and continue to, and express through that is something we should think about on the coast and ask, What does the coast want? What kind of sound do our oceans want? And, and to question and to wonder which, which sounds are disrespectful and which sounds are too much?