Melisa Acimis
At the intersection of ideas and action, this is Longitude Sound Bytes, where we bring innovative insights from around the world directly to you.

I’m Melisa Acimis, Longitude fellow from Sabanci University, Istanbul, Turkey.

Welcome to our ongoing series on imagination, where we are exploring the roles of individuals, technologies and research that is helping advance understanding in ocean science and space technology! In this series, we spoke with scientists about their work in underwater sound monitoring in our oceans.

In today’s episode we are featuring highlights from a conversation I led with John Ryan, senior research scientist at MBARI. 

As an economics student I was interested to hear about the effects of sonar on living beings. We started our conversation with his role in the field.

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John Ryan
In order to understand life in the ocean, we need to understand not just the forms of life, but also their environment, their very dynamic environment. Oceanography is an integration of multiple science disciplines: biology, chemistry, physics, even geology. All of those together allow us to understand life in the ocean.

I finished graduate studies on the east coast of the United States in a state called Rhode Island. There I learned to study physical and biological oceanography. And then it was time to take that next step after school and that is a postdoc, a postdoctoral research position. So I came to MBARI for a two-year postdoc… 24 years ago. I’m a biological oceanographer at MBARI. MBARI, by the way, stands for Monterey Bay Aquarium Research Institute. So we’re a nonprofit research institute, affiliated with a public education center called the Monterey Bay Aquarium, and our job is to develop and apply new technologies to advance ocean science. So on any given day, I might work with autonomous robotic submarines. In fact, we’re starting an experiment tomorrow that will have three cooperating autonomous robotic submarines (it’s amazing) studying microscopic algae in the ocean, particularly the kind of algae that produce harmful algal blooms. My work could also involve listening in the ocean.

Melisa
Our main subject.

John
Yeah, studying ocean sound. For that, I do both research to understand natural sound, from ocean life—because many ocean life forms use sound in all of their essential life activities… so we can hear their lives, really—but we also study ocean noise and how human impacts can negatively affect the ocean soundscape and the lives of ocean animals that use sound.

Melisa
Great. What is your favorite thing about your work? And is there a philosophy behind your actions?

John
My favorite thing about my work is understanding the beauty and complexity of life in the ocean. I love it every day. My second favorite thing, or it’s equally favorite, I love to share the excitement of ocean discovery. I love to do education and outreach. And I get to do that in my work, which is fortunate. I won’t just engage the public in lectures, for example. We also work on public exhibits, technologies where people can walk into a free and open public education center, push buttons on an exhibit and learn about the ocean soundscape.

Melisa
What is this exhibit? Can you elaborate on that?

John
So imagine that you walk up to a large screen, and in front of you is a beautiful image of the ocean off coastal California. And there are a series of buttons embedded in this graphic and you can push a button and then in front of you on the screen, ocean sound will come to life, but you won’t know what that sound is from, you will only see a visual representation of the sound. A line will move through that visual representation as you hear it. So you’re fully engaged with the sound. It’s a way for people to engage with the sound first, guess what it could be, and learn what it is. We built two of those so far and I have a third to go to another public education center — because where we live, there is a lot of tourism. So people come here to vacation, which also gives us a chance to reach many people with this knowledge through our exhibits.

My philosophy- I was going to be in the world of business. I did this job in business to see what it’d be like and I realized, when I’m 50 years old, I won’t be happy because I won’t have contributed anything to make the world a better place. I will have made money for a business and that can be healthy. You can support a good economy. That’s great, but I wanted to do something that would help us live in greater harmony with nature. Because all around me I saw how we were destroying nature. So I changed direction and I chose to major in biology because I thought that would be very important to living in harmony with nature because it’s the science of life. And if we understand the science of life, we can understand how to be harmonious with it.

Melisa
Great answers. I’m impressed with your idealistic way. Can you summarize the ocean sound monitoring project in a few sentences for a lay audience?

John
Yes, the importance of understanding ocean sound is that the ocean is a world of sound. It is a strange world to us, but one in which sound travels very powerfully. It travels far, and it travels fast. And what that means is, ocean life has evolved to use sound in so many ways. So just by listening, we can learn so much about ocean life, about their life activities: communication, navigation, foraging, socialization, reproduction. We can hear it. It also means that we have to be careful about the noise we introduce to the ocean, because it can cause harm.

Melisa
I read about how far sound travels underwater and I came across some key words such as sound channel, hydrophone, and by doing a little of this research I have seen SOFAR. Could you speak about the nature of sound underwater? And how that may be significant for marine life?

John
Yes, you mentioned the sound channel or the SOFAR channel. That is a location in the ocean, the location being depth, really, because it spreads out across the ocean. The sound channel extends across an ocean basin, 10,000 kilometers of the Pacific. And what it is, it’s a place where there is a minimum sound speed. And just the way sound energy travels through the ocean, that minimum in the sound speed that is determined by the physical properties of the water, traps the sound energy and allows it to travel farther than it otherwise could. So that’s a unique thing. And so that’s how we can hear sound produced at one side of an ocean basin and all the way on the other side, if that sound has a sufficient intensity, source level, and a low frequency — because low frequency sounds travel much farther than high frequency sounds.

And then you mentioned also finding the word hydrophone. Well, a hydrophone is just an underwater microphone. And what it is recording, at the very least it is recording the pressure variations that result from a sound wave just as the very process that allows us to hear sound in air. So we record those pressure oscillations that result from the sound. And we record that at a very high sample rate — in our case, we’re sampling sound pressure at more than a quarter million times per second, so a very high sample rate. And the reason we do that is because many animals in the ocean are using sound that’s far above our limit of hearing. So if we’re going to detect their sound production, their use of sound, we have to sample at a very high rate. For example, some species of dolphins or sperm whales will produce echolocation clicks (to help them find their food in a dark ocean) that have a frequency more than five times greater than our upper limit of hearing. So it’s very high frequency. We sample pressure in the ocean with a hydrophone at a very high sample rate, then we can study many sources of sound. Since we’re on the topic, there are really three categories of sound that we can study: biological sound, or biophony; sounds of the Earth, or geophony; and sounds of human activities, anthropophony. We study all of those.

Melisa
Could you elaborate on the effects of sound in the ocean on mammals?  What should be done to reduce adverse effects?

John
There are really four ways that our noise can have a negative impact on ocean animals. The first is interference with communication. It’s called masking. It’s like if you and I were trying to have this conversation, and someone was operating a jackhammer next to my chair, it would be really difficult for us to have that conversation, and in many cases, we are preventing them (marine animals) from communicating with one another. A second harmful effect of our noise is a behavioral disturbance. We can cause a population to move away from a source of noise, when in fact that population needs to be there in order to survive because their food resource is there. So we can cause them to be malnourished, for example. And then a third way that we can have a negative effect is to cause acute or chronic stress. You know how in people we can measure stress hormone levels, like cortisol and such, and we can feel that stress. We know stress has many negative effects on our lives, in our bodies. We’ve learned that our noise also has caused stress in marine mammals. The last effect is that if a sound is so loud, so intense, it could actually damage body tissues. So it could destroy their hearing, temporarily or permanently, it can harm their hearing. And there are even indirect effects. For example, one of the deepest diving mammals, the beaked whale, it lives (forages) so deep in the ocean, and there have been these very dramatic occurrences of beaked whales washing up on the beach and dying. And the reason they died is because they experienced very loud sound, very loud sonar. The sound didn’t cause their death (directly), but they panicked. They swam to the surface very fast. And if you go from a very deep depth at high pressure to the surface at low pressure too quickly, air bubbles come out of solution in your bloodstream, and it causes terrible things.

Melisa
As part of our imagination theme, we are interested to learn if there is room for imagination in your line of work. If so, could you speak about that and share an example of your approach to coming up with or developing new ideas?

John
Imagination, as you know, is important in everything humanity can do. And it’s very true in science. Let’s talk about two areas: research and education. For research, it’s very important to imagine what it must be like for the life of a species that you’re studying. So for example, imagine weighing 150 metric tons, but feeling weightless. And imagine speaking with only your voice, no technology, and being heard by your friend 100 kilometers away. Imagine needing to eat tons of krill (shrimp) every day in order to survive. (This describes the life of a blue whale.) This imagination gives us a sense of what it’s like for the species that we want to understand and protect. And some of these species (like blue whales) are still endangered. They’re still listed as endangered because their populations were decimated by commercial whaling. So we have to imagine what it is like for that species to survive, and better yet thrive, to recover from the harm that was done by commercial whaling. And then imagination immediately comes in when you enter the world of data. You know, one hydrophone, one little tiny hydrophone, collects two terabytes of data in a single month, 24 terabytes in a year. One little instrument. And so here you are, you’ve got this year of data, a mountain of data; what do you do with it? How do you begin to sift through all that data to find the sounds produced by different species? And each species can produce different sounds. How do you sift through that to understand what species are living here in this region, in this biologically rich, bio-diverse habitat? Who’s here? When are they here? What are they doing? It takes a lot of imagination to apply analytical tools to a mountain of data and to come out with understanding. Lots of imagination. I guess what I’d also say is that we’re never just working with sound data. We get other types of information from satellites that orbit the Earth and look down at the environment and tell us, how is it changing from year to year, from day to day? And how did the animals respond to that?

And then I think, very briefly, that it takes a lot of imagination to translate from the language of science into the language that everyone understands. Science is full of its terminology and its complexities. But your job when you are taking that information into education is to use your imagination to create communication that people not only understand, but in a way that allows them to connect with ocean life. If people don’t have any awareness, science can bring them awareness. But if people don’t feel any connection, why should they care about that (species or topic)? Well, then it’s hard for them to understand why we should work for conservation to protect these beautiful ocean environments and species. There is imagination and learning to help people connect.

Melisa
Could you tell us one thing you would change in your career life? What would you say to your younger self?

John
What would I change in my career life? I think I would have taken the pressure off myself at a younger age, because as a young professional scientist I was a little bit, how do I put it, anxious or nervous that I was never doing enough. That my work was not good enough.

Melisa
You’re a perfectionist.

John
Yes. Thank you. You are right. And in that way, I think I caused a little bit of suffering for myself needlessly. That also caused me to not communicate as well as I could have about what I want to do with my career, how I value my contributions. Instead, I looked to other people to assure me that I was contributing enough. I think what I would have said to my younger self is: Relax, have confidence that this path that you chose is right for you and that people value your contributions and enjoy your work. Don’t worry so much about what you’re doing. Just focus on making a meaningful contribution, and that’s enough.

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Melisa
Talking to John Ryan was illuminating. Since his way of thought of ocean and biology is so holistic, I realize that every action I make gives a birth to new consequences over animals in the ocean, especially our noise pollution turning to pressure on these animals. Also, he likes educating people to make a connection between these species and us so that we have a motivation to save the planet and have empathy.

We hope you enjoyed today’s segment. Please feel free to share your thoughts over social media and visit Longitude.site for the episode transcript. Join us next time for more unique insights on Longitude Sound Bytes.