Offshore wind farms are a sustainable option for producing energy, but little is known about their effect on fish on aquatic invertebrates. In this episode, we talk to Arthur N. Popper (University of Maryland) and Kathryn A. Williams (Biodiversity Research Institute) about research priorities to better understand how sound and vibration from wind farms may affect aquatic life.
Associated paper: Arthur N. Popper, Lyndie Hice-Dunton, Edward Jenkins, Dennis M. Higgs, Justin Krebs, Aran Mooney, Aaron Rice, Louise Roberts, Frank Thomsen, Kathy Vigness-Raposa, David Zeddies, and Kathryn A. Williams. "Offshore wind energy development: Research priorities for sound and vibration effects on fishes and aquatic invertebrates." The Journal of the Acoustical Society of America 151, 205 (2022); https://doi.org/10.1121/10.0009237
Read more from The Journal of the Acoustical Society of America (JASA).
Learn more about Acoustical Society of America Publications.
Music Credit: Min 2019 by minwbu from Pixabay. https://pixabay.com/?utm_source=link-attribution&utm_medium=referral&utm_campaign=music&utm_content=1022
Offshore wind farms are a sustainable option for producing energy, but little is known about their effect on fish on aquatic invertebrates. In this episode, we talk to Arthur N. Popper (University of Maryland) and Kathryn A. Williams (Biodiversity Research Institute) about research priorities to better understand how sound and vibration from wind farms may affect aquatic life.
Associated paper: Arthur N. Popper, Lyndie Hice-Dunton, Edward Jenkins, Dennis M. Higgs, Justin Krebs, Aran Mooney, Aaron Rice, Louise Roberts, Frank Thomsen, Kathy Vigness-Raposa, David Zeddies, and Kathryn A. Williams. "Offshore wind energy development: Research priorities for sound and vibration effects on fishes and aquatic invertebrates." The Journal of the Acoustical Society of America 151, 205 (2022); https://doi.org/10.1121/10.0009237
Read more from The Journal of the Acoustical Society of America (JASA).
Learn more about Acoustical Society of America Publications.
Music Credit: Min 2019 by minwbu from Pixabay. https://pixabay.com/?utm_source=link-attribution&utm_medium=referral&utm_campaign=music&utm_content=1022
Kat Setzer 00:06
Welcome to Across Acoustics, the official podcast of the Acoustical Society of America's Publications Office. On this podcast, we will highlight research from our four publications. I'm your host, Kat Setzer, Editorial Associate for the ASA. This episode, we'll be speaking with Arthur Popper of the University of Maryland and Kathryn Williams of the Biodiversity Research Institute about their article, Offshore wind energy development: Research priorities for sound and vibration effects on fishes and aquatic invertebrates," which appeared in the January 2022 issue of JASA. Thanks for taking the time to speak with me today. How are you both doing?
Arthur Popper 00:44
Very well.
Kathryn Williams 00:45
Doing great.
Kat Setzer 00:46
Yeah, awesome. So first, tell us a bit about yourselves.
Arthur Popper 00:49
Why don't I start. I've been doing fish bioacoustics for a long time, over 50 years. Started out with my real interest being in how do animals detect sound and how do they use sound. But over the past 20, 25 years, my work has evolved to become much more applied-- that is using the same ideas that fish can detect the new sound to try and understand how they respond to manmade sounds, anthropogenic sounds. And so my work for the last decade or two has primarily focused on rate issues of effective sound of fish, and regulatory issues, and going into questions of international significance in terms of the use and the effects of such sounds.
Kathryn Williams 01:36
And so yeah, I'm Kate Williams. I'm the director of the Center for Research on Offshore Wind and the Environment at the Biodiversity Research Institute, which is a wildlife research nonprofit that's based in Maine. I've been working on offshore wind energy and wildlife issues since about 2010. I'm actually an ornithologist by training. So my background is mostly with birds, but I've worked on a variety of wildlife taxa over the years. And really, for working on offshore wind, you know, thinking about its effects on the environment has to some degree be holistic, because, you know, any industrial-scale development has effects on sort of multiple aspects of ecosystems that you need to be able to understand in order to help avoid or minimize those effects as much as possible.
Kat Setzer 02:25
Yeah, that really makes sense. So to help our listeners understand offshore wind a little bit better, can you tell us about the industry and its development?
Kathryn Williams 02:33
Yeah, so offshore wind started in Europe in the early 1990s. So there actually have been quite a lot of studies on effects to wildlife and ecosystems. In the US, we have a large terrestrial wind energy industry, but not a large offshore industry yet. There are currently seven offshore operational offshore wind turbines in the US: five off of Block Island that started operations in 2016, and then two off of Virginia. But there are several commercial-scale offshore wind farms that are actually under construction now and are expecting to start operations in 2024. And those are both south of sort of Massachusetts/Rhode Island area. And there have been many more offshore wind energy leases that have been sold by the US Federal Government, both on the Atlantic and Pacific coasts. So there's quite substantial growth in the industry in the US that's expected in the coming decades. And that's also true globally; there has been substantial recent offshore wind energy development in China and other parts of Asia, for example. A lot of this new planned development is going to use traditional designs for turbine foundations. So those are big, big monopoles that are driven down into the seabed. But in deeper waters where there isn't that sort of shallow continental shelf like there is, for example, in the Eastern US, there are actually new floating turbine designs that are going to be increasingly deployed as well. And so that's what we're talking about in the Gulf of Maine and off of the coast of California and the Pacific US, but also in Japan, waters off Scotland-- places that the water just drops off really, really quickly from shore.
And offshore wind farms have a range of effects on marine systems. So some could potentially be positive for wildlife, in terms of creating new habitats and artificial reefs, but there are also concerns related to underwater sound. And that's generally focused on the potential for sort of deleterious effects on aquatic species. But offshore wind is also a source of sustainable energy. And so, you know, trying to figure out how to balance the need to move away from fossil fuels from a climate change perspective, but while also trying to figure out how to minimize environmental effects of that new development as much as possible is sort of where my my research focus is.
Kat Setzer 05:13
Okay, yeah, that's really helpful to understand how... It's a very fine balance, it sounds like. So this paper arose from the 2020 State of the Science Workshop on Wildlife and Offshore Wind Energy hosted by the New York State Energy Research and Development Authority. Can you tell us a bit about what that was and how it led to this paper?
Kathryn Williams 05:33
Yeah, so the state of New York is very interested in environmentally responsible offshore wind energy development. And so they have been bringing together collaborative groups that include the offshore wind industry and regulators and resource managers and scientists to try to work together towards that, that goal of environmentally responsible development. So we had a conference called The State of the Science Workshop on Wildlife and Offshore Wind Energy, which in 2020 was virtual due to the pandemic. But instead of having sort of breakout groups for discussions at an in-person workshop, the virtual format actually provided us more flexibility to spread out discussions over longer time periods with workgroups. And so these... We had seven workgroups. They were focused on birds, marine mammals, sea turtles, a sort of a variety of topic areas, and they met virtually over about a six-month timeframe, and produced reports, summarizing group discussions and recommendations. And one workgroup was focused on offshore wind's sound effects on fishes and aquatic invertebrates, and the recommendations of that workgroup, and the report that that group developed was the basis for the paper we're talking about today.
Kat Setzer 06:51
Yeah, okay. I see. So can you give us some background on what we know about how underwater sound sources affect fish and aquatic invertebrates?
Arthur Popper 06:58
Yeah, we can talk about that a little bit. The problem is that there are about 34,000-35,000 species of fish, and far more species of aquatic invertebrate, many of which hear, and so trying to do what people working on marine mammals do, which is come to generalizations, is really hard, because the diversity of fishes, and then even more so for aquatic invertebrates, is far more than any other group of animals, other, at least, vertebrate animals. And so it's really impossible to say, "Well, this is the case for fish," or for invertebrates, because there's so much variation in these animals, you know. So the issue is that all of these fishes, and many of the aquatic invertebrates hear, and they use sound as part of their life. So even... so some use sound for communication, for reproductive behavior, for telling when there's predators around, but all hear and all use sound to get a gestalt of their environment, at distances that are much greater than they would get from other senses. That is, sound can travel for great distances, hundreds of meters more in the dark, and things like that, whereas visual signals only are available during the light and close to the source. So, so sound becomes the major source of information for fishes and invertebrates. So anything that happens that disrupts the ability to listen to these sounds, is potentially harmful to the animals. If you think about in terms of humans, when we're walking on the street, we're getting a lot of information about the world around us from sound. It could be for sound from behind us, from above us, from distances away. And we're using that all the time to make decisions as to what we're gonna do, where we're going to go, and things of this sort. Well, these aquatic animals do the same thing. And so anything that happens that interferes with the ability to use the sounds, even if they don't make sounds, even if they don't communicate with sound, has a potential for impacting the environment. So, sound becomes very important. And so the problem issue with the with wind farms and other sources, whether it be sonar, or shipping noise, or so on, of these things, is they have the potential for interfering with the ability to detect sound, they have the ability to mask detection of sound, they have the ability to prevent animals from hearing sounds of biological relevance. And so we're in a position where any sound that comes from offshore wind or any source has... Our concern is that we have missed that sounds may interfere with the ability of populations of animals to to survive. Now, one of the problems with this, in addition to the sound itself, is that we're now becoming aware that substrate vibration, the the actual sound that's in the substrate, may also play a role in impacting animals. So, when a pile driver, when a wind farm is being put in place with pile driving or with other sources, other mechanisms, the sounds can also get in the substrate, and the sounds getting in the substrate are very intense, and they travel substantial distances. And so animals living on or in or just above a substrate can also be affected by these sounds that come from the substrate. So, it's a very complicated environment, acoustic environment for these animals, and we have to think about offshore wind and other sources in terms of what can they potentially do to to affect the animals? How can it affect the behavior? Can the animals attack detect sound in the presence of these sounds that humans are producing? Now, I will add that it's very likely that a lot of the sounds don't bother the animals; that is we walked down the street, there's sounds all around us, and we've learned to ignore them, or they're not loud enough to bother us. So it's not every sound that's potentially harmful, or causing changes in behavior, just some sounds. But it turns out that things like pile driving when they construct offshore wind, or shipping noise, may be loud enough to actually cause problems for these animals. So, but we can't generalize. You can kind of generalize among marine mammals. Fishes are a much, much more difficult group of animals to work with, because they vary so much in how they detect sound and how well they detect it. And invertebrates we know almost nothing about at this stage of the game. So while we, while we're suspicious, while we strongly suspect they can be interfered with by offshore wind sounds, we really don't have any idea.
Kat Setzer 10:26
Okay, yeah. So there's a ton to consider. How did you decide what topics should be research priorities in the upcoming years?
Arthur Popper 11:44
What we did was have a series of workgroups that came up with a variety of ideas. There was a small... a workgroup was 30 or 40 people from all over the world, it was quite quite an impressive group of people, with broad interests, from animal biology to the physics of the sound to a range of different things. And we talked about potential ideas. Then a small group got together and refined this list, down to a list of topics that seemed feasible to initiate in this short timeframe. One of the things we're trying to do is not come up with ideas that it will take 30 years to solve, but to come up with a list of ideas, list of topics that, were feasible to deal with in the next four or five years. This doesn't mean we're covering every topic, but we're trying to refine. So what are the most important questions to ask? And can they be accomplished if there's the resources in the next five years? So we came up with a list of seven different issues, we shared it with the whole group, and the group actually voted. And it was interesting, because it was general consensus that what the most important topics were to consider over the next several years, we of course, didn't want to ignore the things that would be longer term. And we kept those in the paper, and as additional items, but the focus really was on seven areas or so that are higher priority. And then the problem becomes how do you start answering those questions? And how do you start exploring them? And that's the really big issue here.
Kat Setzer 13:16
Okay, yeah, that sounds very practical. And actually, let's start talking about some of the goals the working group came up with. the very first one was to identify key species or groups for studies of the effects of offshore wind sound exposure. And you already kind of talked about this, that there's 34,000 species of fish and more of invertebrates. So why did you decide this was important? And what would research around this look like?
Arthur Popper 13:40
It's a really critical question. In fact, in 2014, we explored the same issue with regard, with general issues of offshore of sound and fishes. And the conclusion we came to is it's impossible to study 34,000 species. It's also not relevant because a good number of these species don't live in environments that are near offshore wind, and/or they're in very deep water at distances away. And they are, they're not of economic importance. So what we try to do in this case is come up with ideas that would encompass what species are relevant to the areas of concern, what species are of biologically greater importance or would give us information that we could extrapolate to other species, what species are considered to be endangered, and a whole range of different things that are far more than five or six species, but at least try to come up with some principles of what species to pick. One of the important things we thought about is are there species that were relevant to all locations or many locations in which offshore wind has been developed? So for example, tuna or scombrids, two related species, salmonid species, are... These are all species that have broad economic and relevance... that have principles that we can extract from them that might be applicable to other species. So we're trying to find, how do you kind of get down to a smaller group of animals. We didn't come up with a final conclusions, because it needs to really be the people who are developing the offshore wind projects to come up with what they think is most important to them. But at the same time, what we want to do is encourage them to think together, rather than say, "Well, we'll look at gobies and another group or look at some other group of fish." Let's instead, let's look at fishes like sturgeon that are economically important and very critical with regard to environmental issues, and in danger of being endangered species, rather than some species that have really less interests broadly. So but whether that'll happen or not, it's hard to say. But we're certainly encouraging a group, everyone to get together and talk about this to try to come up with at least some groups of species that are most relevant.
Kat Setzer 15:55
Yeah, that absolutely makes sense. So once those species are selected, the group suggested studying behavioral responses of fishes to offshore wind farm development. What kind of behavioral effects might there be in response to offshore wind farm development?
Kathryn Williams 16:08
So I'm realizing that it might be helpful to talk a little bit about what the different sound sources are, that arise in relation to offshore wind energy development. Yeah, so just to take a quick quick step back, there are a variety of sources of sound that are related to offshore wind farms, and they vary by phase of development. So in the pre-construction phase, you have sort of geophysical/geotechnical surveys of the seabed. Those are not as intense as like airguns that are being used for oil and gas exploration, but they do create noise that can be detected underwater. Construction is by far the noisiest part of offshore wind development. And and as Art said, particularly, when you're driving those piles into the seabed, it creates a huge amount of sound and also substrate vibration. And then post construction, there is some noise that is generated from operational turbines; it's more localized. And then at all phases, you have noise related to vessel activity. And probably again, particularly during construction, because there are so many construction vessels out there during the construction phase. So in fact, one of the environmental reasons that people are really interested in looking at floating turbine designs is that you don't have to drive a pile into the seabed in the same way for a floating turbine. You do have to attach multiple anchor points into the seabed, so it's not totally without sound, but it is substantially quieter during construction than more traditional turbine foundation designs are. So when we're talking about potential behavioral responses of fishes to offshore wind development, it is going to vary by development phase potentially. And so I think a lot of what we're talking about is more focused on construction, although not exclusively. Certainly, you know, we think there's the possibility for displacement from areas in the vicinity of sound sources, which is essentially avoidance, where animals are moving away from noisy sources of sound. And that can lead to sort of effective habitat loss, right, in either the short or long term. If there's some reason why they are using that habitat, whether it's a good foraging ground, for example, or something, and then are forced to leave it, they may be end up in an area that isn't as good for foraging anymore, and it may actually affect them. Or maybe the place that they move into is just as good, right. So like trying to figure out the effects of displacement are really hard. But that does seem like a behavioral response that occurs across different taxonomic groups. And that seems like a likely response to offshore-wind-related sound for at least some species. There's also a lot of potential for other behavioral effects as well, and Art touched on some of them earlier. In terms of things like masking of acoustic communications, particularly if sound is used during hunting. You could see it potentially affecting foraging efficiency; there might be changes in foraging behavior. There might be changes in reproductive behavior, particularly again, for fishes that use sound during reproduction, like spawning. So there are a variety of sort of potential behavioral changes that we're interested in.
Kat Setzer 19:37
Okay, yeah. So what are some potential methods of studying those behavioral responses?
Arthur Popper 19:42
And that's a, that's a good question, because there's some controversy among those of us interested in these questions and, you know, I think you'll get... You know, we're gonna get different answers from different people. But since I'm here, I can give my opinion. So the ideal way to do this is in a lab study; we control the fish; we control everything. The trouble is, lab studies don't work, because the sound field produced in a lab is so different than that in the wild that the animals aren't exposed to the kinds of sound they would get in the wild when they're really exposed to things like offshore wind sounds in general, or construction. I won't spend much time on this, but the point is that sounds in fish tanks, or even large enclosures are so different than the sounds in the wild. And changing and setting up a tank to be pristine and equivalent of that, in the wild is almost impossible, or extraordinarily expensive. I once did that, and the cost was several $100,000. So we're not talking about something that's simple to do. At the same time, there are some lab studies that are so much easier things like physiological responses, to find out what changes there are in hormone levels, which is a really important question, or things like developmental studies of what happens when an animal is very young, exposed to sound. But those studies have got to be taken with tremendous caution, that the sound field is very likely to be not normal. The critical studies really need to be done in the field. And those are very hard and very difficult to do. Because you have to be able to watch what the animals are doing, and observe how it responds to sound. Now, this is a lot easier in marine mammals, where the animals come to the surface a lot. So you can get some good information for them. It's much harder and inefficient, 50 meters of water, 20 meters of water, where the animals are under the water all the time, and they move around, and it's just very hard to watch what they do. So there has to be some compromise someplace. One possibility is doing experiments is very large, and I use the word cautiously, marine cages, where the animals are in some large area, but they're restricted; they can't go too far. That even has problems because in normal environment, animals can move anyplace they want. And so if they're restricted, they can't do that. So their behavior may change. But at least then you can get the sound field to be normal and ask some questions you just can't reliably or accurately asked in the laboratory. So it becomes very hard; these are very hard questions. They're very expensive to to answer, because it's all in the water. You need all kinds of interesting gear that are expensive. So to answer, the question of how to do this is not, is not trivial. It's actually very, very hard. We've been, we've been doing stuff like this for 50 years now. And we still haven't figured out quite how to do it. And when the few cases where it has been done reasonably successfully, it's been very, very expensive and very hard to do.
Kat Setzer 20:57
Oh, wow. Yeah, that does sound incredibly challenging.
Arthur Popper 23:07
But it's incredibly fun.
Kat Setzer 23:08
Yeah, there you go. Right? The next priority was to promote standardized collection of high-quality data. And I can kind of intuit why you want the data that you have folks collecting to be standardized, for comparison purposes. Can you explain a bit more why this is important, though?
Kathryn Williams 23:22
Yeah, and I think you hit on it. As Art said, there's tens of 1000s of species of fish. And it's often pretty hard to study them. We can't study everything. And so we really need to be able to take data that are collected on one species or location or system and try to apply the knowledge gained to other situations, recognizing that there are a lot of factors that could influence species' responses from one location or type of sound to another. But if the way that data are collected is as standardized as much as possible, it does make it easier to try to stitch together research findings from different systems and begin to build a deeper understanding of underlying processes and be able, ideally, to better make predictions to species or locations or sounds where direct research hasn't been conducted yet. And there are a couple of different examples of standards groups that have come together to try to agree on how best to collect data. A lot of people are working on this. I know ASA has a standards group, for example, that tries to deal with these kinds of questions. Art has been involved with these types of efforts for years. Specifically in relation to offshore wind, there are also several groups trying to standardize wildlife data collection methods. One example is the regional Wildlife Science Collaborative in the Eastern US, which is a collaboratively funded group focused on research and monitoring of wildlife and offshore wind energy. And they have taxa-based subcommittees that are developing specific data standards for some types of data such as passive acoustic monitoring for marine mammals.
Kat Setzer 25:02
Okay, that is very interesting. So the next priority was to conduct hearing sensitivity studies for selected species. That sounds fun. How do you go about doing that? Do you put headphones on your fish?
Arthur Popper 25:13
Absolutely. They're actually cartoons showing that. But it's not easy because there's controversy here. And...
Kathryn Williams 25:22
Always. Always, Art. There's always a controversy.
Arthur Popper 25:28
Controversy is this. What is hearing? What question are you asking? What... When I started doing this work a long time ago, the way we asked questions of what fish can hear was behavioral experiments where we actually presented a sound to a fish, and it had to do something to indicate that it heard this. And that's a very standard methodology. You can do it with, you do with humans who go into a soundproof booth, and they raise a hand when they hear a sound. With animals, you can do it by getting them to do various behavioral tests. And we did that with fish. Trouble is those are very time consuming and not that easy experiments. So what people have gotten to today with fish and even some invertebrates, is to basically record from the brain or from the ear and say that the animal detected the sound because there's a signal from the ear that's picked up by this, by the mic, by the electrode. The trouble is, that's not hearing. Now, a lot of my colleagues won't agree with me, but I think we're on the way to persuading them that we're right, in that hearing is defined as being able to behave or respond to a sound. By this, I mean that if a sound comes to the ear, and you record that it's there with an electrode, that doesn't mean it ever gets to the brain. It may be that the sound is not loud enough to get further into the brain. Or it may be that it's the wrong frequency. Or it may mean any number of other things. It's only... So that's not hearing, that's just the ear responded or did not respond to the sound. It's hearing when the animal sound gets to the brain, when the animal can react to the sound. And it's like you're listening to me; it's not just your ear responding. But your brain is saying there's a sound, and you're shaking your head, or you're disagreeing really, or you're responding. It's the exact same thing with an animal, with a fish, marine mammal. And those kinds of experiments that actually say the animals detected the sound are very hard to do. And they're hard in the sense of they take time, and they take a lot of effort. They're actually technically very simple. I could train the fish in a couple of days. It's not nearly as easy as recording for the brain, but the brain recordings are aren't really what we need because that doesn't say if the animal hears a sound or not. So, so the, and to get into the question, it's really, these are very hard things to do. And one has to decide what questions one is asking. And not everyone agrees, although I think people are coming around now. And seeing that, that you... To really get the answers to what happens with offshore wind sounds, or any sound, is how does the animal behavioral respond, or not respond, but at least the sound gets to the parts of the brain that would allow response. Now, the same kinds of question, issues arise for invertebrates. The trouble is, we know so little about them, that it's almost impossible to generalize to, to the sounds that we detect. But these become the most important things. You know, the fact is, if this offshore wind produce the sounds the fish can't hear, why worry about them? It's that simple.
Kat Setzer 29:03
This is a much more philosophical question than I expected.
Arthur Popper 29:08
It's one that I think a lot of us have been thinking about. And there are a number of us who have been trying to persuade the community of late that this is actually a fundamentally important question. If the fish doesn't hear the sound, why worry about it? Because it's not going to responsd. And the other thing is, you know, some of the sounds are actually attracted to fish. So Kate very rarely talks about the fact that this concern, do fishes leave the area of wind farms? But in fact, a lot of the sounds attract the fish, and for a fisherman who's going to do recreational fishing, a wind farm area might be a cool place to go because there may be a lot more animals there. The trouble is commercial fishermen find them to be you know, they're not coming in the same quantity. And they may not be the same animals that a commercial fisherman is interested in. So it's these are, you're asking very complicated questions. Got it?
Kat Setzer 30:02
So, for another possibly complicated question, the working group recommends developing a long-term, highly instrumented field site. What would that site look like? And how would it be created?
Arthur Popper 30:12
Yeah, I was thinking about this again. And it's not easy. Because it needs to be... Such a site... The advantage of such site is that, because they are very expensive to set up, and to monitor and to control, it would be really nice to have one or two locations in different parts of the world that could be used by a range of investigators asking a range of questions. Trouble is setting these up would be very difficult and very expensive. And there's not gonna be much agreement as to what the best site is. We need a site that's easily accessible, that's easy to use, that has all the facilities you want, and has all the species you want. Somebody working on cod, Atlantic cod, which is a critically important species, needs to go someplace where there are such species. They can't just bring Atlantic cod to someplace there's no such species, or they can't bring a saltwater fish to a freshwater environment. So setting up something like this would be the ideal way to go. But I think that getting a site that's suitable, that's usable year round, that has the right acoustic environment, that has the right sources, that would mimic offshore wind, will be extremely difficult, and very, very expensive.
Kat Setzer 31:31
Okay, yeah. So then, finally, you suggest a feasibility study to examine sound mitigation options for fishes and invertebrates. How would you do this study?
Arthur Popper 31:40
Well, the problem is that most of the work being done these days is on marine mammals, and well, they're very cool animals, it's very easy to do the studies on marine mammals, because there aren't that many species, up to 30 species. And...
Kathryn Williams 31:53
I think the marine mammal community would object to saying that their work is easy.
Arthur Popper 32:04
I said relatively easy, because there are few species. And the auditory system in the marine mammals is reasonably similar from species to species. It's more like dealing with a group of humans. It's not, there's not the diversity that we see in fishes, the auditory system, the lateral line system, is highly diverse in fishes. And it's even more diverse when it comes to invertebrates. And so asking the right question is infinitely more difficult for fishes. At the same time, I'm going to argue that fishes, that the diversity of these guys is so great, and their importance economically is so great, and in terms of human survival, so great, that asking the right question is very, very hard.
Kathryn Williams 32:53
There have been a lot of efforts to try and figure out how to mitigate sound from offshore wind development, particularly construction-related sound. And those efforts to date have focused almost exclusively on marine mammals. So trying to figure out how to contain the sound or reduce the amount of sound that's emitted at specific frequencies to reduce exposure of marine mammals, particularly like harbor porpoises and species that are occurring a lot in Europe. And a lot of those mitigation approaches probably are just not going to be as useful for fishes and invertebrates. As one example, you know, Art talked a little bit about substrate vibration. None of the methods that have been sort of developed to date deal with trying to mitigate sound in the substrate. They're all trying to mitigate sound actually in the water. And also, current mitigation methods don't do a great job of cutting the lower sound frequencies very much, which is often what a lot of the species we're talking about actually can detect. This priority in the paper was sort of, it's sort of a feasibility desktop-type study, just trying to say like, all right, of all of the mitigation methods that have been developed for marine mammals or suggested, which of these seem like they might have any applicability to fishes and invertebrates? And if there aren't any, should we be thinking about trying to develop some? And as Art said, we don't want to try to mitigate if if it isn't affecting fishes, like we need to do that step of trying to figure out what the effects are. But we also probably need to start thinking now about if there are significant effects, how would we try to mitigate those? And we don't really have strategies right now. So this was trying to, like, get people thinking about that, I think a little bit.
Kat Setzer 34:44
Right, start strategizing so that you can do it eventually. Okay.
Kathryn Williams 34:47
Yeah, that was the thought.
Kat Setzer 34:50
So then, to sort of shift gears, you talked about some long term priorities as well. What were those? And why do you see them as longer-term focuses than the other goals we've discussed?
Kathryn Williams 35:00
Yeah, it's a good question. You know, the end goal for all of these priorities is really trying to understand cumulative effects to populations and ecosystems. But in order to do that, you need to understand effects to individual animals first, or to specific populations or specific habitats. And so the shorter-term priorities that we identified are intended to be building blocks, basically, where we can build our knowledge base, and feed the information that we learned back into sort of conceptual models of population and ecosystem consequences of offshore wind disturbance, with the overall goal of saying like, okay, we don't want to affect individual fishes, but really what we're interested in is like, are we having population or ecosystem scale effects? And so that's the long-term goal. It's not something that you can just design one study to get at. You'd have to design a whole bunch of individual studies answering different little pieces of that puzzle, and then try to weave them all together. So that's, that's sort of the long term, the long term goal of all of the priorities in this paper, actually.
Kat Setzer 36:17
Got it. And do you have any other concluding thoughts for us?
Kathryn Williams 36:22
One concluding thought, and Art touched on this some already, is the importance of funding, and having sort of regional funding needs to address some of these big questions, to develop, like, the large-scale testing site, you know, for example. There is, I think, a need around offshore wind to develop some kind of mitigation and research bank or something, some kind of larger funding source, that allows us to take a coordinated approach to research. So having one pool of funds that can sort of support broader research issues, it would help make more efficient use of resources. I think it would lead to higher quality work. You know, there's definitely interest in the offshore wind world in developing this kind of fund. Not just focusing specifically on sound-related impacts, necessarily, but thinking about offshore wind effects on the environment more broadly, there have been funds like this that have been developed in the UK, and it's in progress, I think, in the US. There's also, I think, a similar need in a lot of other marine industries, including other energy sources, like tidal and wave energy, there's a lot of parallels to the types of research questions and coordination needs that we've identified for offshore wind. But sort of, regardless of the topical scope of a fund, like this, some kind of regionally coordinated research funding mechanism would be so helpful to ensure that research and monitoring activities are directed towards highest priorities, to really help us get to that understanding of cumulative effects.
Kat Setzer 38:07
Yeah, that totally, totally makes sense.
Well, thank you again for taking the time to talk with me today. I hope this interview helps our listeners understand how important the need for research on the effects of wind farms on fish and invertebrates is. I know I'm personally interested in finding out how much these research endeavors progress and hopefully we'll have some more JASA articles about them. Thank you for tuning into Across Acoustics. If you would like to hear more interviews from our authors about their research, please subscribe and find us on your preferred podcast platform.