The Lake: Sound & Nutrients

Aquatic ecologist Catherine O'Reilly is the guest on this episode. She lives in Duluth, MN and is the Director of the Large Lakes Observatory at the University of Minnesota Duluth. One of her conference presentations was titled, "Is there a party in the stream tonight..." and she found that underwater sound varies depending on lunar timing. 

When we recorded this episode, it was very smoky outside as wildfires had started near Ely, MN.

The book Brenna read from is called Theory of Water by Leanne Betasamosake Simpson. 

Sound clip at the end provided by Dr. O'Reilly. You'll hear water striders rubbing their legs on their back, as she describes in the podcast episode. 

Learn more about deep water sculpin here and see a video of them. They are in the freeze category of flight or fight and they prefer to keep their bellies on rocks. 

Episode photo: Lake Superior/B Greenfield, 7/18/26

Transcript

unknown 0:01

Okay.

SPEAKER_00 0:03

Hi, Dr. O'Reilly. I'm so pleased to have you as a guest on my podcast home. And I think you're an excellent person to have on this season, which is about Lake Superior, because I hear that you are interested in lakes.

SPEAKER_02 0:22

Yes, and thank you so much for having me. I'm excited to be here. I am a great lover of lakes. There is like no doubt about that, yeah.

SPEAKER_00 0:32

How long have you been a lover of lakes? And tell me about when you first fell in love with a lake.

SPEAKER_02 0:37

Oh wow. Um well I have to admit that when I grew up, which was mostly not in the United States, I did not have a lot of lakes near me. That place I remember is the ocean and also reservoirs that were not super clean water. But we had a long period of drought, and during that period, like we had increasingly higher levels of rationing of our water in the house, and so I did definitely notice that. And it made me think about how important water is for society. And then when we moved to the states where I went to high school and college and have been here ever since. Where were you as a kid? Uh South Africa mostly, actually, uh, for most of that time. In the states, when we moved to Minnesota, it's kind of impossible not to like notice lakes and how many there are. There's just they're all over the place, right? And so I'd never really been in a place with like so much water everywhere all at once. Um and so I think that was when it was like a little happy place, maybe for me, right? I coming from a country where we did not have access to water very readily at that time because of the drought, to this land where these it was just covered in these beautiful bodies of water.

SPEAKER_00 1:59

And you moved here for high school? Yeah, high school.

SPEAKER_02 2:01

To Minnesota.

SPEAKER_00 2:02

Okay, all right.

SPEAKER_02 2:02

And were you like in an urban area or I I was in Morris actually, which is like not really very urban, but um, and so a lot of agriculture, but the agriculture there isn't maybe as like predominant as it is in the sort of Illinois, sort of real real central Midwest area where it's really flat, and that's literally all you see is corn and soybeans. Um, so you there's like sort of this rolling hill thing in Minnesota with like every low part is like a lake or a wetland. So it sort of feels like you're kind of going over a hill, and there's another body of water, another lake. And there is something like so peaceful about getting out on a lake, like because you can't be in a car, right? To do that, you have to be in a boat, and even if it's a boat with an engine, it somehow has a sense of freedom about it that you don't get really from anywhere being on land. You can go literally any direction you want, right? And there's no constraints, there's no roads, there's no traffic stops, there's no trees in your way if you're trying to walk through the woods or across the grassland. It's just this open expanse that's free for you to explore. Like anything's possible. Yeah, a little bit, yeah. You can go to that one side of the lake and you'll see something, but then you can go and explore a different side of the lake and you know, see maybe something slightly different. Yeah. I never thought about it like that.

SPEAKER_00 3:22

Yeah, yeah. And then um, I don't know, what do you notice the most when you're out on a boat? Like, do you like to get in the water or like look around you or listen? Like, how do you engage with water when you're on it?

SPEAKER_02 3:38

That depends upon what I'm doing on the boat. So, like if I am out on the water for fun, it is probably like in a canoe, ideally, maybe in the boundary waters or on a river trip, and then I'm just kind of observing, observing the landscape around me and kind of feeling a little bit what it's like, that my place in that big landscape that's out there. If I'm on a boat for scientific purposes, then I am not paying any attention to any of that. I am like really focused on where are we, what are the water conditions like, um, you know, should I be getting ready to take samples? Um, you know, is it safe? Are my students safe? Where is all the stuff? Did we forget any work? You know, yeah, it's work, it's like work, it just happens to be on a boat in the middle of the lake.

SPEAKER_00 4:33

Yeah. Uh-huh. Yeah. Um, and then I was reading that you're an aquatic ecologist, which sounds like it's related to water. What do aquatic ecologists do, and like what's the type that you are?

SPEAKER_02 4:46

So aquatic ecology is kind of a really big broad term. It's like forest ecology, you know, but we study any kind of water, aquatic ecologists, rivers, lakes, you know, usually fresh water. Otherwise, you'd be like a marine biologist. So my um area of interest is lakes, more so than rivers, and the um water chemistry. So the nutrients in the water, what their concentrations are, and how those nutrients levels might change if we have different types of land use around the lake, like human activity or forested landscapes, and also how the lake is going to change over long periods of time, particularly with respect to changes in like air temperatures.

SPEAKER_00 5:35

And is Lake Superior your focus now that you have moved up here?

SPEAKER_02 5:40

Um not yet, but they I do have projects I want to be doing in the Lake Superior area and the St. Louis River. Um, but a lot of my work was done on Lake Tanganyika in East Africa, and so I still have a very strong connection to that lake, and I'm still hoping to go back and like work on my next project out there.

SPEAKER_00 6:05

What's that lake like?

SPEAKER_02 6:06

It's a lot like Lake Superior, except it's in the tropics. It's huge and deep, and is very unique in how it functions, like how the water mixes, um kind of how clear it's one of the clearer lakes in the world, it's one of the more productive lakes, it's also one of the oldest lakes in the world, too. So it's very letting lots and really, really high biodiversity. And just like Lake Superior is really important like culturally for us in terms of like tourism and fishing and ice fishing and things like that, Lake Tanganyika is really important for socioeconomic reasons in East Africa. It's traditionally been a really important source of food through the fish protein that the local communities catch.

SPEAKER_00 6:57

And that's changing.

SPEAKER_02 6:58

Yeah, it is. It's changing like as the climate has uh changed the water and warmed up the surface water there. We don't see the same kind of nutrient availability for the food web. So it's sort of like the lake's not getting the fertilizer it used to get, so that's the algae aren't growing as well, and the um, you know, there's less food for the fish. So the fish populations are decreasing. It's also getting just kind of a bit too warm for the fish, right? It's already a warm lake, it's very tropical, so making it a little bit warmer like just makes it more stressful to be a fish in warmer water, as it has been for us around here the last few days in this really hot weather. That's really hot and you kind of you know, you don't eat as much, you don't feel as great. So yeah.

SPEAKER_00 7:43

So you're also interested in the fish and the lake?

SPEAKER_02 7:45

Yes, the fish are important because um that's what a lot of humans sort of identify with or need or have cultural associations with. But I'm not really like a fisheries biologist, like I don't study fish population growth dynamics or species interactions or things like that. But I am interested in you know what's happening under the water and how are all these different pieces of a lake, you know, what are all those different pieces under the water and how do they fit together? And for me, also, like how do I help people understand how dynamic a lake is? Because when you look out on a lake, it just like just seems like water, right? And it's kind of just got a surface, but all the cool stuff about lakes is like under the surface. Okay, it's like where you go, people go scuba diving in lakes, and then you can see all kinds of cool fish in lake technique if you go snorkeling or diving. Um, or if you like you think the lake is always kind of looking the same, but you start taking its temperature and it's like really variable, like all where you are and time of year and all this stuff. So lakes are really like dynamic beings almost, and it's so I've been thinking, I spent a lot of my career thinking about how do I help people understand like all the cool bits of a lake other than just water.

SPEAKER_00 9:08

So, what are the cool bits of Lake Superior? The cool bits of Lake Superior. Yeah, like how is that tell us about its oh it's it's cool bits well or how it's dynamic, yeah, that you wouldn't see that you're looking at it.

SPEAKER_02 9:21

Yeah, yeah, good point. So some of it, the part that you can kind of see is the ice, like the ice in the winter and the ice around. Yeah, the ice is beautiful. It's because the lake is so big though, we can't see like what's going on when you look out on the lake, right? You just see what's going on right in front of you. And there's ice like all over other portions of Lake Superior that we can't see very easily here in Duluth. So it's sort of hard to appreciate sometimes how much ice there is out there because we don't see it right offshore from us. But that that ice that's moving around and how much ice we have every winter that really can impact how fast the lake warms up in the summer. So when the okay, yeah. So these winter conditions, as the winter conditions change, they're influencing the summer conditions in the lake too. So there's kind of a seasonal connection between the the ice, the how much ice cover we have, how soon the ice leaves the lake, and then how fast the lake starts responding to like more sunlight and warmer temperatures in the summer. So that's one thing. Like it's hard to you can see the lake has changed, but it's hard to see year to year to year to year, like how that variation is happening, like how some years a lot of ice, you know, their summer is going to be a certain way, another year less ice, it's gonna impact the sun. Are people measuring the ice? Yeah, they are with satellites because you know, no one like you can't really like take a boat out, really, and the lake is too big to do it from shore. Like you can't use some smaller lakes. Yeah, yeah, exactly. You should not go out on there in unsafe conditions. So a lot of what we know about ice cover on these really large lakes is from satellite imagery.

SPEAKER_00 11:07

Yeah, those are cool pictures. What about the nutrients? You mentioned nutrients, and yeah, I would guess there's like algae. I don't know, like, or there's carbon. I don't know. What are the things that like what are the key components of Lake Superior and how do they cycle?

SPEAKER_02 11:23

Yeah, so algae are very important because they are like the plants for the food web. So if you want any other thing, anything in your lake other than just algae, you need to have some algae because that food that algae is like the food source for these tiny little invertebrate critters, and these little invertebrates are the food source for larval fish and small fish, and then big fish eat the small fish, right? But all of that is like based on algae, just like on land for humans, like our diet is like it's it's somewhere down the line, even if you're a meat eater, there's some something that's eating a plant, right? So the lake food web is the same, but it's just based off of algae. And those algae, because they're just plants, they need they need things to grow, right? They need sunlight, um, and then they need some kind of warm temperature. Because if you've ever tried to grow tomatoes in Duluth where it's cold, they apparently don't grow very well. Are you speaking from experience? Uh yeah, a little bit, but I've also heard that if you below like Fourth Avenue, Fourth Street, but like you're too close to the lake for it to get warm enough to really grow things. Um so yeah, so they need light, they need warmth, but they also need nitrogen and phosphorus and carbon. Are they the big major components of like life in general? Okay, yeah. If you have DNA, you have you need phosphorus. If you have amino acids, you need nitrogen. And that's all of life has those things. So in order for algae to grow, and they need it's the sun to come out, the days to be longer, they'll grow faster when it gets warmer, and they need to have some of these nutrients. Now, when you lakes are so big like Lake Superior, these nutrients are pretty much washing off the land. Nitrogen and phosphorus are kind of getting washed off the land and into the lake. And when the lake is that big, it it's it's they're just not very high concentrations of these nutrients in the water. And so that's one of the reasons our water is really clear in Lake Superior, because there's we can't grow a lot of algae. The lake just can't support huge algal populations because the concentrations of these nutrients are really low. If you go in contrast to like a lake in the Twin Cities, say where people are fertilizing their lawns, or there's a golf course nearby, and so in that fertilizer is nitrogen and phosphorus. And so when that runs off the land into the lake, there's like lots of nitrogen and phosphorus available for the algae in the lake, and the lake is warm because it's shallow probably and it heats up really quickly. So you've got warm water, light, and lots of nitrogen and phosphorus, and then you have these big algal blooms happening.

SPEAKER_00 14:10

But there might be is there a point where you have too much where you nitrogen and phosphorus, like where you don't want as much in your lake?

SPEAKER_02 14:16

Because you hear about like runoff into lakes not being great, yes, and it sort of depends upon how much algae you want in your lake. Okay. If you get too much phosphorus in your lake, you can um the type of algae that does really well, because just like there's lots of types of species, tree species, there's lots of types of algal species, there's some algal species that do really well under like uh high phosphorus availability but low nitrogen. So if you have more phosphorus relative to nitrogen, those types of algae will just start to thrive and do really well. The thing about those types of algae is they are um in a group of algae we call blue-green algae or cyanobacteria, and they're also um the ones that have these big algal blooms at the end of the summer, and some of them can produce toxins, they're also just not very nutritious and tasty, so for the fish, for the for the yeah, food for the tiny little guys, and so they kind of just end up dominating because nobody wants to eat them, they taste gross. A lot of them are kind of like clear too.

SPEAKER_00 15:27

Could you still eat them? Could people eat any of the algae that are in the lake?

SPEAKER_02 15:31

Yeah, absolutely. For real? Uh well, not the ones with the toxins. Yeah, don't touch those. Uh, don't even go in the water, right? Yeah, yeah. With when you have the that kind of toxin that is produced as a neurotoxin and the the water crisis in Toledo from 2014 was what was that? Oh, yeah, okay. It was in Lake Erie, so okay, but it was um a big algal bloom that happened, and Toledo takes his drinking water from Lake Erie, and the algal bloom was had this type of these cyanobacteria algae in it, and they were producing this toxin. And so people you couldn't like use any of their water for three days. And it wasn't like you can't drink it, it was like you can't shower, you can't touch it, you can't do anything with the water. And they couldn't like filter it out. No, we don't have the technology to filter this out. Really? Yeah, it's a big deal. Yeah, it is a big deal. Yeah, it's dissolved in the water. Okay, um, and so and it didn't used to be that common that you would have these kinds of harmful algal blooms. Um, but as you pointed out, you put more stuff in the water, more phosphorus, and more fertilizer, more runoff inputs. Plus, when things get warmer and the algal populations grow really fast, you're more likely to kind of create the conditions in the water that would favor these sorts of algae. So, um yeah.

SPEAKER_00 17:00

What are the types of things? Because you're concerned about kind of the wit lake warming, right, over time and the impacts of that. Um are there any kind of protective things that people are doing anywhere to like help with warming water temperatures? Um wow, that is a politically loaded question.

SPEAKER_02 17:22

Okay, we can move on. You can uh always edit it out depending upon what yeah, I'd say you know the best way. I mean, can you how are you gonna cool Lake Superior down if it gets too warm? It's huge. It's like really like sure, you could probably build a thing and do it and figure it out, but it would be like immensely technologically advanced and require tons of energy to do that. So um the best way to cool water down in the summer is to like try to not let it get too hot to begin with, I think.

SPEAKER_00 17:56

Right? I see what you're saying about the question.

SPEAKER_02 18:01

Like anyway, as a scientist, there's some words we're phrases we're we're using less often now than we used to, yeah. So maybe if we could, you know, like kind of maintain status quo, try to make sure that our environment stays stable. Um, that's like with temperatures that's always helpful for management.

SPEAKER_00 18:22

Um it's a tricky thing though. It is like it's just like this is our reality right now. It is. Um a lot of things are changing, you know, as we're like having to stay inside because there's a lot of wildfire smoke. So exactly. Yeah.

SPEAKER_02 18:37

Yeah. So that and I mean then the other thing is uh for like maintaining high water quality in lakes is yeah, reducing like fertilizer runoff from the land into the lakes or other things like we don't just dump raw sewage into lakes anymore because that also has lots of nutrients in it and can cause algal blooms. So we have water wastewater treatment plants and they remove a lot of the stuff that we don't want going.

SPEAKER_00 19:02

So those are things that like help maintain good health of the lake. And when you take its temperature, you're like, you're doing well, like come back next year for your annual.

SPEAKER_02 19:14

We do put a thermometer in the lake and we get a little reading, yeah. And we're like and we write it down and we're like, okay, yeah, we'll check on you again next year. Hopefully, you're about the same temperature. So yeah, but because lakes are so dynamic to get back to your original question, we can't just do that once a year, right? Like, because you oh for sure. Like, yeah, like even if you did that, measured your own body temperature once a year, it'd be a little bit variable. So, yeah, so we have um some temp thermometers out in the lake, and they're collecting data like continuously, like every few seconds they're getting a reading, reading at the surface, reading a deeper in the water column, and that helps us like kind of understand if the way the lake is working and functioning is changing over time, too.

SPEAKER_00 20:00

Okay, uh, and what are some of the other research questions that you're interested in that you can talk about in relation to Lake Superior?

SPEAKER_02 20:10

Yeah. Um, so I am interested in like riverine, small riverine input and the nutrients that brings into the lake. I'm also interested in um understanding the soundscape of Lake Superior and also the estuary, which is a very powerful part of how water moves through the landscape, like and is an important place for fish. What's the estuary? Good question. Sorry, I like went from lake to estuary. Yeah, so estuaries are the pla are places where a river kind of moves out into a large body of water and a big river into a large body of water, and we usually think about them in the oceans where like the Hudson River goes out into you know the Atlantic Ocean. Um, but we have an estuary here right in Lake Superior from the St. Louis River, which is pretty big and has this big space that it flows through before it gets to the lake. Of course, in our estuary is like a port. Yes, and with lots of you know, activity, human activity that's happening in that area, and that's pretty common in most estuaries because they're good harbors, good places to put harbors.

SPEAKER_00 21:22

Are they? And they're I I'm very interested in like these liminal spaces, like in between spaces where you're like it's not the river and it's not the lake yet. Yeah. Do you find that um there's like the river like rushes into the lake, or how do they like meet and merge?

SPEAKER_02 21:37

Yeah, like where does one end and where does one begin?

SPEAKER_00 21:40

Yeah, or um is it a place of like speed or like swirling, or like how would you describe uh an estuary, you know, or just waiting?

SPEAKER_02 21:51

I'm sure there is like a technical definition that I just don't know because I'm not really a estuary researcher. Um But they are usually places that are sort of these hot spots of where these two environments are overlapping in temporally and spatially, in you know, sort of in varying ways. Um they're important for big lakes because these big rivers are bringing in these nutrients. And so those nutrients are gonna help stimulate like the food web in that that area because you're bringing in phosphorus and nitrogen from all around the watershed that this big river has flown through. Oh okay. And those nutrients are gonna be very important, and they're gonna you're gonna have like more algae near where these big rivers enter these big bodies of water.

SPEAKER_00 22:43

Because phosphorus and nitrogen, they just kind of like do they fall to the bottom? No, they're just kind of flow.

SPEAKER_02 22:48

They're dissolved just like Gatorade is dissolved, Gatorade powder is dissolved, and the algae are like just teeny teeny tiny little plants, and they're kind of just they're sort of neutrally buoyant, so they're just sort of hanging out around in the water, and you know, so all these nutrients and the algae, as long as it's all up near where the water is getting lots of sunlight, the the algae can take up. Algae is smaller than I was imagining.

SPEAKER_00 23:13

I was imagining like waving seaweed in the bottom. Yes. Is that different than algae?

SPEAKER_02 23:18

Um, not in the sense that they are both plants. Yes. And it is true that especially like in ocean systems, you think about seaweed and algae as being synonymous, and they kind of are also really, they're both plants. But in lakes, um we there are big, big plants that kind of wave around and they're attached to the bottom.

SPEAKER_00 23:44

Um startle you when you swim through them.

SPEAKER_02 23:46

Yes, they do, yeah. It's like um, and those are also algae, but there are also algae that are single-celled, like they're just really tiny, you're not even gonna see them in the lake until you put it under a microscope. Okay, yeah.

SPEAKER_00 24:02

And that's what the phosphorus and nitrogen are going into, and then they're just starting the reactions of like growth and getting bigger. Yeah, okay.

SPEAKER_02 24:08

Yeah, and the reason for these tiny little algae is because like out in the middle of the lake, you can't be like attached to the bottom because it's dark. Because Lake Superior is so nothing can grow there. Yeah, not well, nothing that needs sunlight. Yes, okay. So plants can grow in the bottom of Lake Superior. There's no light down there. Bacteria. Okay. You know, there's fish.

SPEAKER_00 24:31

Fish, yep. Are there? Yep, there are fish in the bottom of Lake Space. Are there different fish in the very bottom?

SPEAKER_02 24:36

Um, yeah, they are they are different. They are some sculpten that are live in the deep waters of Lake Superior, and um, they're specialized to like living in deep high pressure environments. Wow. Yeah. Okay, there's similar types of fish in the ocean to sculpin. So these are freshwater ones.

SPEAKER_01 24:58

Yeah.

SPEAKER_02 24:59

Oh, they're very, very cool. They're not very good swimmers because that far down in the water.

unknown 25:06

I know.

SPEAKER_02 25:07

Does that sound weird? It does. They're very good at like kind of hopping around, they gotta stick close to the bottom. They like to sink down, kind of lie on the bottom of the lake, and then um try to like catch little small like things that float down or little shrimp that also live in the lake. How big are they? Very small. A sculpin or the shrimp?

SPEAKER_00 25:30

The sculpin.

SPEAKER_02 25:31

Um, oh my gosh. Um shoot, I should know this. Like, I want to say like six. Oh, like the size of your hand. The size of your hand. Okay.

SPEAKER_00 25:41

Not 35 feet.

SPEAKER_02 25:42

No, no, no, no. I'm just imagining the bottom. No, they're they're small, and they partly because there's it's cold down there, and there's also not a ton of food. So it's hard to get really big if you don't have a lot of food to eat. Okay. It's hard to grow fast if it's cold.

SPEAKER_00 26:04

So yeah, yeah. Um, I've been learning a lot. This is so interesting. And I think we should oh, um, talk about underwater sounds. Yeah. And then I'll have one more question for you. But um, I came to a really great talk that you gave or presentation recently on the blue heron, which is also mentioned by Sam Kelly in his episode. And so you were playing different recordings of underwater sounds. Yeah. And I'm reading this book called The Theory of Water. Um, I don't know if you've seen it. And there was a section, because I haven't really thought about underwater sounds before, so I'll read this section to you. And then maybe you can just tell me a little bit about what attracts you to underwater sounds or react to this. Yeah, and we'll have one more question, and then we'll wrap up, I guess. I don't want to keep you too long. Um, okay. So the molecules that make up the water in Stony Lake are closer together than the air molecules. And this means that the sound of the bullfrogs, chi dang, that's my best try in Ojibwe, travels faster and more easily across it. Of course, this is why people sitting at the shore can hear the conversations in the canoe in the middle of the lake. And we think of the lake as an amplifier in this sense, except it technically isn't amplifying anything. The molecules are just closer, more connected, and the transmission of the sound is faster than when the sound travels through air to my human ears, which have perfectly evolved to hear sounds traveling through air. This is why I feel surrounded or engulfed by frequencies created by this community of bullfrogs.

SPEAKER_02 27:44

Yeah. I actually haven't thought about like that interface of the water and the air very much with sound. So that was fascinating. There is, I mean, water is denser than air, so sounds that happen underwater do move much further because there's much uh the mall because all those molecules are close together, and the way sound moves is it's sort of molecules bumping up against each other as a pressure wave goes kind of across that space. So if you molecules are not very close together, then eventually a molecule might move forward and not bump into anything else, and then the sound is lost, right? But underwater, you're always going to have pressure bumping into another molecule, and so you can carry that sound much, much further.

SPEAKER_00 28:37

What are some of the coolest things you've heard underwater?

SPEAKER_02 28:41

Um, I think one of the most surprising experiences I had was sitting in a boat on a nice warm day, and we had a hydrophone, which is just a microphone, but it goes underwater, so I guess it's got a fancy name. And we're it just it was really quiet and warm, and it's just three of us in the boat, really, really, really quiet. And I put my earbuds in and I put this hydrophone underwater, and it's just like screeching, screeching, screeching noises. And then you pick it up out of the water, and I'd hear nothing, just silence, and you put it underwater. It's like the screeching noises, like like just this cacophony of like shrill kind of sounds. Um, and it's a like a boggy kind of place, so you know there's no big fish in there or anything. There it was fishless, actually. And there's no it's not frog sounds, and it turned out that like it was these water striders, they're insects, they live, they they kind of uh they're like water boatmen, they kind of swim around but under the water, and they make these sounds by rubbing their legs on their backs and rubbing their legs together, yeah. And so it's almost like it's hard to describe. I want to say like nails on a chalkboard, but it wasn't quite that like jarring. But uh maybe like walking into a room with like hundreds of tiny baby birds, all baby chickens all screeching or something you'd heard it, yeah. I'd never heard anything like that before.

SPEAKER_00 30:16

Wow, and it's so surprising because it's quiet up above. Yeah, but then there's like this really loud noise. It's like so can you hear um more sounds underwater because of just the properties of the molecules than you would be able to hear if you were just recording out in the air?

SPEAKER_02 30:33

Yeah, you can hear. I mean, um, because like underwater is like actually so noisy, it's more complicated for species to make distinctive sounds because everything is loud, as opposed to, for example, birds where it's quieter above, so your birds can have very distinctive calls. Um, but yes, there's definitely a lot of noises going on underwater.

SPEAKER_00 31:01

Yeah. Yeah, and that can tell us things about what's happening there. I really liked your point about how like healthy ecosystems, there's a lot of like sounds, and that draws other creatures because they hear these sounds.

SPEAKER_02 31:15

Oh, the study with the corals, yeah, where they're they're realizing that you know, actually, if you wanted to do coral restoration, one thing that they found was effective was if you played the sounds of a healthy reef, that the your coral like fish would be attracted to that, I guess, and they would come, and then the restoration project would do better because you were sort of attracting all the species you wanted to have present and restoring some of the natural processes, I guess. Yeah, I like that.

SPEAKER_00 31:44

That was really cool. So, thank you so much for being my guest. My last question is um, what do you wish for yourself and the Lake Superior and your relationship going forward?

SPEAKER_02 31:58

What a beautiful question. Um in the context of kind of what we were just talking about with sounds, I would like to understand Lake Superior's song, maybe? Like what is it that what does the estuary sound like with all the different fish that we know go through it, that we some of them we know make sounds? Um and how do those sounds and songs like change over time? Um and kind of what does it mean for people when we hear that part of the lake when we hear what's happening to the lake as all these fish and things move around and it like how that makes people feel?

SPEAKER_00 32:45

Yeah, yeah, to hear those sounds.

SPEAKER_02 32:47

Yeah, to to yeah, exactly. And how do people do do people think about the lake differently when they hear what it sounds like? Because that might be like one way to phrase that question.

SPEAKER_00 32:59

I mean, I certainly did when I came to your presentation.

SPEAKER_02 33:02

It's amazing, isn't it?

SPEAKER_00 33:03

Yeah, yeah, yeah.

SPEAKER_02 33:04

Yeah, and we already do a lot of this in like marine environments and terrestrial environments, right? Where we we listen underwater at National Marine Sanctuaries, and we we hear where the whales and the dolphins are, and we use that information to like uh steer away from them and things like that to create the the boundaries of protective zones with birds, like you're listening, who's there, how when are they calling? Um, if you're a birder, you probably know identify birds by sound, and that tells you, you know, what's going on in that community? Is that like are there lots of different species that are kind of a healthy forest environment or not? And so I think we can do the same thing underwater with freshwater systems. Can we listen? And will that just that listening tell us something about how healthy that environment is? Because otherwise it's very hard to tell, right? How are you gonna tell what's going on under the water and what a lake is really like? So this might be a new way for us to think about like, is that lake healthy?

SPEAKER_00 34:07

Because I think like I can um I can hear in my mind the sounds of like whales or seals or things like that, because I've been played those sounds before. Oh, cool. But when I think, and I think a lot of people are familiar with those sounds, underwater sounds, but when I'm like, oh, what does it sound like under like superior or in the water? Yeah, I don't have much I know what waves sound like, but less underwater. So um I think it's really exciting what you're doing. And I wish you lots of discoveries and happiness and success with it.

SPEAKER_01 34:41

Oh thank you so much. I'm excited about