Ep 154: Conservation in a cup (with David Lodge)
How do you find an invasive species that no net can catch? What happens to the scientist whose research samples end up in federal court?
In this episode, we talk with David Lodge, a freshwater ecologist at Cornell University and past president of the Ecological Society of America. In 2009, David's lab detected invasive carp from DNA in bottles of Illinois River water, including above the electric barrier meant to keep the carp out of the Great Lakes. That result helped found the field of environmental DNA, and it brought congressional testimony, a Supreme Court filing, and five hours of unfriendly questioning on the witness stand. Drawing on David's recent retrospective in the journal Environmental DNA, we follow the science from a cup of water to the courtroom, visit the Wisconsin lakes where the invasive crayfish he has watched for more than forty years are now collapsing on their own, perhaps driven by a parasite new to science, and ask what it takes for science to inform policy without pretending to drive it.
Cover art by Brianna Longo
-
John Drake 0:05
So, John, tell me about the Chicago River. In 1900, the city of Chicago actually reversed it. The river had been running into Lake Michigan. The lake was the source for Chicago's drinking water, and the river was carrying the city's sewage. So, engineers dug a canal and turned the river around. The sewage went the other way, back into the Missis. The sewage went the other way toward the Mississippi.
Marty Martin 0:29
So Chicago got clean water.
John Drake 0:31
Chicago got clean water, and North America got a permanent connection between two continental watersheds that had been separate since the glaciers. Anything that can swim can now, in principle, get from the Gulf of Mexico to the Great Lakes.
Marty Martin 0:44
Okay, hold that thought because I want to go to France for a minute.
John Drake 0:48
Okay, go to France.
Marty Martin 0:49
In 2008, a group of French researchers published a short paper in Biology Letters. They had gone out to some ponds, scooped up some water, and found DNA from American bullfrogs without ever seeing a frog, it's the paper that founded the entire field of environmental DNA.
John Drake 1:05
And here's the part I love: the American bullfrog is definitely not French. It's invasive there, so the founding demonstrated, so the founding demonstration of eDNA, the proof that you can detect an organism from the traces it leaves in water, was itself an invasive species detection. The tool arrived already pointed at the problem,
Marty Martin 1:24
which is roughly what our guest thought when someone handed him that paper.
John Drake 1:28
Our guest today is David Lodge. He's a freshwater ecologist at Cornell. He ran the Cornell Atkinson Center for Sustainability for the last 10 years. He's a past president of the Ecological Society of America, and I should say up front, he was my PhD advisor at Notre Dame, so I'm definitely not a neutral party here.
Marty Martin 1:45
Noted. Go on.
John Drake 1:47
By 2008, David had already spent 25 years or so working on invasive species, and the thing that kept beating him was detection. You can't manage an invasion you cannot find. Then Lindsay Chadderton put the bullfrog paper on his desk. The next spring, they went out on the Illinois River looking for big head and silver carp, which had been working their way up the Mississippi for 30 years and were headed right for that Chicago canal.
Marty Martin 2:10
And it worked on the first try.
John Drake 2:13
It worked on the first try, and then it got complicated. They found carp DNA above the electric barrier, closer to Lake Michigan than any fish had ever been caught. Within a year, David had filed a declaration with the Supreme Court, testified before Congress, testified in federal district court, and started receiving Freedom of Information Act requests for his lab notebooks. A Chicago business leader called the work a glorified science fair project. A science reviewer wrote, "I am not convinced that this is a reliable technique,
Marty Martin 2:43
but despite the initial controversy, eDNA is now standard practice. The Fish and Wildlife Service runs 1000s of water samples a year in the Great Lakes,
John Drake 2:52
and it's gone well past detection. David's group has pulled population genetics out of a bucket of water, allele frequencies, population structure, all of it, without catching a single fish, and he's now arguing we should do the same thing with samples from the air.
Marty Martin 3:06
But it won't only be fish, fish that we talk about with David. We'll talk about crayfish too. David's been watching the same set of Wisconsin lakes for about 42 years, and the invasive crayfish that stripped those lakes bare are now, and about half of those lakes, disappearing on their own, nobody knows why. But now the plants are coming back,
John Drake 3:24
and we talk about what it costs to be the scientist in the room when the decision gets made, which is something David has thought harder about than almost anyone.
Marty Martin 3:31
I'm Marty Martin,
John Drake 3:32
and I'm John Drake,
Marty Martin 3:34
and this is Big Biology.
John Drake 3:46
Yeah, well, David, let's start with an interesting little detail that I think is lovely. The paper that founded the whole field of DNA, eDNA, the paper that founded the whole field of eDNA. I'm thinking about Fisatola and colleagues from 2008 detected American bullfrogs in French ponds, and the American bullfrog is an invasive species in France. So the very first demonstration that you can find an animal from the DNA it sheds was itself an invasive species detection. When Lindsey Chatterton put that paper in front of you, did you see your own problem, sort of staring right back at you?
David Lodge 4:23
Sure. It was like, wow! Not only is this amazing that there is that much DNA out there, but there they just did this test on a something that was obviously convenient for them, but directly relevant to the problem that I spent so many decades thinking about and working on: invasive species.
Marty Martin 4:47
So maybe say a little bit more about eDNA because, like, in one sense, people will expect it to be there. You know, we've all seen the crime dramas where some form of that is how how you're implementing. In murder or some some other crime, but on the other hand, it's not the most robust molecule in the world. I mean, it's it's going to break down to some extent, and I know that that's something that your protocols will have well worked out. But yeah, I mean, how how do we need to think about it as a as a sort of checking the world for invasions and such?
David Lodge 5:21
Yeah, on the one hand, it shouldn't have been surprising or revelatory to environmental scientists that eDNA hangs around because, as you point out, Marty, forensic scientists have been using DNA, eDNA of humans for a few decades now to detect particular humans at at potential crime scenes, so in one sense we should have thought of this before, but on the other hand, yeah, we know a lot of things about eDNA that might immediately, from first principles, make you a little skeptical. You know that it doesn't last forever, and on the other hand, you know from ancient DNA studies that have been going for quite a while-that under certain conditions DNA can hang around forever. So it's a little-it still is somewhat amazing. I think that the applications that are so important, including invasive species, but we may get to others, are in a sort of sweet spot that there is a realm of of the environment and important questions that we can ask where DNA hangs around just long enough to be useful, and so I mean maybe it's worth backing up a little bit. I mean so when we're talking about DNA, it's it's it's just the DNA that any organism leaves behind. Forensic scientists have been taking advantage of humans, leaving their their skin cells or saliva around for a long time. But every organism, in whatever environment it's in, is shedding cells that contain DNA. And it turns out there's enough of it. In fact, there's a lot of it. I mean, we continue to be surprised by how much of it there is. So detecting it is not a problem, and and identifying it is not a problem. And so we have a way to monitor to detect a single organism or all organisms that are in an environment with, if you're talking about aquatic systems, which is what I usually think about, with with a cup of water.
John Drake 7:30
So, if I have the chronology right, it was back in the spring of 2009. You were out on the Illinois River, and you know, filled some bottles up with water from a place where you thought some of these Eurasian carps were to be found, you wrote a couple of years ago in an essay that that was a eureka moment for you. I'm wondering if you can tell us a little more about that day.
David Lodge 7:53
Yeah, Andy Mayhan and Chris Jurdi, I think, were the ones who actually went to the Illinois River and and collected water in some places where people thought Asian or knew Asian carp were, and places where we thought they weren't, and that was just that was shortly after reading the Fisatola paper, and we just thought quiet we would do this sort of quietly. We didn't tell anybody we were doing this, and they came back within a couple of days. Andy, you know, says, "Wow, this this works. We we we found we found DNA of Asian carps where we knew they were, and we didn't find it where we had good reason to think they weren't. So right away we were like, it was the closest thing to sort of a eureka moment in my career that I've had, where we were still at that mental stage where we we thought this just can't work. It can't be this this simple, but it was in fact that simple.
Marty Martin 8:53
So you back up just a minute. You said that they had expectations about where the carp wouldn't be and where they would be, and so you found the signals where they would be. When you when you were talking about the utility of eDNA and you know well forensic science has been using it forever. Why wouldn't it work for other things? How yeah? How does that work? So how often is the eDNA? Should the eDNA be there and it's not there? Or if you find it or sort of what's the spatial expanse? And this is weird because I know it's the river; the water moves. But over what spatial expanse is it a useful diagnostic?
David Lodge 9:29
Yeah, these are all great questions, and the questions that skeptics immediately went to, along with many other questions about why what we were detecting was probably not reliable, but the a short answer is that the sort of sweet spot that I referred to earlier is that DNA under sort of normal conditions in a temperate water body, whether it's the ocean or a lake or a. Hangs around from hours to days in the surface waters, and so we we would never say a detection of DNA means the organism was right where we sampled it, right at the time that we took the water sample. But we can say the organism was somewhere close by, or if you're in a, or upstream, if you're in an environment where the water is moving, not that long ago, and for many applications, that is is sufficient, and indeed, in the case where we started out, for better or worse, Actionable, so it hangs around long enough. It does degrade, and there are various things that may get degrade. If it's in particles, it sinks. But when it's in water temperatures that are typical of temperate waters and surface waters, exposed to sunlight, exposed to bacterial activity, it doesn't last that long. Again, hours to days.
Marty Martin 11:04
Okay. Okay. And this work, I think, was inspired by a fairly simple question by Colonel Vincent Quarles, who was interested in you know how sensitive netting and electrofishing were for surveillance. I mean, why was that not really a question, or was it a question? And the EDNA approach was supposed to be more sensitive, I guess.
David Lodge 11:27
Yeah, I think we got such an early and fast and visible start in EDNA because we were just already involved in projects that were very applied with the Army Corps and state agencies around the Chicago area waterway, which connects the Great Lakes and the Mississippi watersheds with a very interesting history, and we had already completed projects where, from the Great Lakes Protection Fund that had made us get quite good at detecting organisms with DNA. We hadn't, we we weren't thinking about it as eDNA at the time, but we deployed various technologies with with engineers, with physicists to get more, get faster and better at detecting small amounts of DNA. So we were technically the lab. I'm saying we because it involved many people in in the lab and the research group. We were sort of pre-adapted technically and intellectually to be thinking about genetic detection. And then Lindsey Chatterton, who worked for the the Nature Conservancy, and worked on some of these projects too. Was frequently sitting in on meetings with the Army Corps where they were wrestling in these sort of public and semi-public meetings with how to manage the movement of invasive species through the Chicago area waterway, because some of those species threatened the Great Lakes, or threatened the Mississippi watershed from the Great Lakes, and so I remember being in one meeting where the the Corps Colonel Vincent Quarles you mentioned and other Corps representatives were really just just hammering the their biological consultants because the consultants could not tell them with any great degree of confidence or precision where the carp were and how many there were. And as a biologist witnessing this, I felt very sorry for the for the biological consultants because they were using the standard gears in in defensible, appropriate ways, but the gears we use to census organisms traditionally are not very good. They're not very sensitive. They're very expensive. They're very laborious, and their level of detection is really low. So the kernel. kept saying, "Why can't you come up with a better way to tell us where these fish are? And then Lindsey comes across the Fisatola paper right after it was published. Comes into my office with Chris and Andy and says, "Hey, we got to talk about this. So that's how that started. We were already technically we had everything we needed in the lab. We already had the intellectual framework and the tools to do genetic analysis of of water. We were already doing that, and then we had this really timely problem into which millions of dollars and a great deal of public attention was focused.
John Drake 14:42
So then, I guess between summer of 2009 and 2010, your lab ran a bunch of samples. I think I read more than 3066. were positive for Big Head, 72 for silver carps. And then they poisoned 10 kilometers of the canal. Can you tell us that story?
David Lodge 15:07
Yes, our lab became out of our desire to provide a public service on an important, timely issue with with great interest. We got ourselves into the middle of a very public, expensive, and on us incredibly demanding technically in terms of cranking out all those samples. That was not something we, a research lab, is really ordinarily desirous of doing or set up to do, But the core wanted the answers, and we were delivering them. And so, without time for writing it up in peer review, we were still delivering those answers, and that led rather quickly to some fairly dramatic management actions. And I don't know that our results alone led to that, but they were certainly important in the public and private discourse. And so the Corps was already managing what was called an electric barrier in the Chicago Canal. Again, this is the sort of choke point between the Mississippi watershed and the Great Lakes, Lake Michigan in particular, they were managing this barrier of of electricity that the theory was to prevent the movement of of fishes, particularly fishes upstream toward the Great Lakes, and so they rode known nine kilometers. I think it was John. You you've got the numbers perhaps better at hand than I do, and we had been detecting repeatedly EDNA, and so from a management ecosystem, public policy perspective, we dearly wished that there were no Asian carp above the barrier upstream toward Lake Michigan, but in fact there they recovered one big head carp in that stretch of the canal, and so we, of course, as researchers whose science was under attack publicly, were were relieved scientifically that what we had been saying Was there? Was there? And of course, you you wrote known nine kilometers of waterway. You do not capture every fish that you killed. So it seems quite likely there was more than one. I heard someone refer recently to if you find two ants in your kitchen, you don't think I have a two-ant problem. You you know that you have an infestation of ants. So that was a moment of great relief and sort of, if you will, public validation of the usefulness of environmental DNA.
Marty Martin 18:00
Okay, one thing that I think you know probably is clear to all of the listeners, but I'm going to go ahead and ask you to to say a little bit about it just to make sure. Why do we need to keep these carp out of the Great Lakes in the first place? I mean, you know, all of this effort for to what end?
David Lodge 18:18
Yeah, the Great Lakes have 40 million people living around them in their watershed. They're hugely important to the economy. The fisheries alone in the Great Lakes is often described as being worth about $7 billion annually, and it supports a huge amount of the rest of the economy in terms of not just recreation and waterway, but navigation and commerce. And why do people want to live there in the first place? So hugely, hugely important economy, hugely important ecosystems are the Great Lakes, and these Asian carp had were known to be working their way up, reproducing and swimming, and working their way up the Mississippi River from their introduction in the Lower Mississippi in about 1974 to 76. I don't remember exactly an introduction, by the way, that had been sanctioned by the EPA, maybe conducted by the EPA, in the thought that these carp could be biological control agents in aquaculture ponds. But as usual, many stories like this-they escaped. There was a flood. They escaped in the Mississippi River, and biologists have been alarmed about this since since 1980 or earlier. And there had been warnings repeatedly by by biologists, including Fish and Wildlife Service biologists, saying, "Hey, these carp are spreading up the Mississippi River, we should be worried about that because, as they spread and became abundant, they may they created dramatic changes in the river ecosystem. Plankton populations plummeted, but both these species are largely planktivores, even though they get to be huge fish. 40 to 80 pounds. They're feeding on. They're feeding on plankton, and so that was changing the food web. Well documented in parts of Illinois River, and and of course we can't know for sure. We and others have published quite a few papers on what they might do if they got established in the Great Lakes, but it it seems wise if it's possible to keep from doing that experiment, that is letting them go into the Great Lakes.
Marty Martin 20:28
Yeah, yeah.
John Drake 20:31
So that was eDNA in a cup of water, conservation in a cup of water, and now air. So you've argued that airborne eDNA should become standard practice for I think biological sampling. There was a Danish study I think you were commenting on where they picked up gray squirrel in a species that supposedly isn't there. So if you're a manager, what do you do with a detection like that?
David Lodge 21:00
Yeah, you don't. I would. I never argue, and no reasonable scientist would argue to take dramatic, expensive actions on the basis of one positive detection of DNA, because there are always ways that that could be a false positive, and we we we can talk at length about what we mean by false positive, but let's just say that you're detecting a species that isn't there and nowhere near. So it's always possible. There's contamination. There's all kinds of things that can happen. So any time you do EDNA, you want to be very thoughtful and try to control for and eliminate, or at least be very transparent about all the ways that this could be a false result, but once you continue surveys, and this is what you would do in any management applied situation, once you repeat those surveys in time and space, and you keep getting a signal, that's when you really should start to really pay attention and consider what, if it's an important species that you either want to preserve or get rid of, what kind of management interventions are are appropriate.
Marty Martin 22:10
So, if the you know your your sort of advocacy was within five years we should be doing airborne EDNA surveillance, what are the steps towards that. I mean, practically, because the first thing that pops in my mind is the massive costs of doing that kind of thing, both the collection of samples and then the analysis. So, how do we get to that in a kind of way that the public gets on board with and actually is tractable?
David Lodge 22:37
Yeah, I think I would think about the analogy of what has happened in the last what 15, 17 years in aquatic EDNA. In both cases, when you when you talk about the expense of collecting water samples and doing genetic analysis, expense is never standing alone. It's always in comparison to something else. What else? What else could you do? What is the cost of the alternative? And in both cases, aquatic and terrestrial or aerial, this is often eDNA is often going to be cheaper and quicker and more accurate in terms of more comprehensive than the traditional tools that we have, which are themselves quite expensive, we often don't have good biodiversity surveys. Biologists are always lamenting that we don't have good biological baseline data, and it's true. And the reason we don't is because it's so darned expensive to find appropriate experts to send teams in the field to use traditional tools of of capture and whatever to detect to detect what's there. So, EDNA is a way to do this that is much faster, potentially repeatable because it's so fast, because it's so cheap relative to those other tools.
Marty Martin 24:01
And and one thing that I think that we might not have time to get into the details of, but I find really fascinating and plan to go look at myself. Whereas before eDNA was largely about detection, now there's the ability to sort of probe molecular variation at a finer scale and get some idea about demographics and other kinds of things that would make management of populations more tractable, more more possible. Maybe,
David Lodge 24:27
yeah. I mean, it's astonishing the degree to which we keep extracting more and more information. We collectively, the scientific community, out of environmental DNA samples, and the samples. To sort of go back to your aerial question a bit. Many samples already exist. Many countries have surveillance networks where they collect water samples all the time. I mean, air samples all the time to detect water pollution. But those those filters often are. Collecting, they are collecting lots of environmental DNA. So, in some sense, we can get a start on the aerial with examples that already exist. And the the Danes are doing that. Matt Barnes at Texas Tech is doing some of that. So, these tools are often there's there's samples sitting around that we can already use as baselines in museums and the like, but but but your your question. Sorry, I've almost forgot your question now. Went off to went went went went off on a tangent there. What was the question again?
Marty Martin 25:33
Well, it's just that now that we have high resolution, I mean, we can sort of look at variation in sequences. I suppose just presence and absence.
David Lodge 25:41
Yeah, the the tools now. I mean, Cara Andrus and and my lab, former graduate student now at Illinois State University, is doing work where we're detecting genetic variation. So, population the the potential to do population genetics from EDNA is opening up and will only get better and better. And there's there's work going on by other people in marine systems for marine mammals, and detecting the abundance. Both there's two two ways to think about detecting abundance from environmental DNA. One is through population genetics, where you can look at at population size through genetics. The other is looking at just how much DNA is out there, and this isn't going to work in all settings for all organisms. But it turns out that in some settings, including commercially important fishes, at least one, the North Pacific Hake, where this has been tested, the amount of DNA in the water is very indicative of the abundance of hake in the in the population, and we know that because NOAA and NOAA scientists and others at the University of Washington, Ryan Kelly have been have done those calibrations, and those are ongoing.
John Drake 26:55
This is a really fascinating topic, and I think we could probably talk for the rest of our hour about it. But you've done so much in your career, and there's some other things we want to ask you about. So you've worked on invasive species, I think, your entire professional life, backing up about 40 years. You were a postdoc at Trout Lake in 83, and you were working on rusty crayfish. Tell us about what Trout Lake looked like in 1983.
David Lodge 27:24
Yeah, I and and I was just up there at Trout Lake last week, continuing to collect data that will now be 44, 44 years, I think, of collections on Trout Lake and other other lakes. When I arrived in 1983, Trout Lake was parts of it. It's a big, it's big lake, complicated littoral zone, nearshore area. But there were parts of it that had lots of plants, underwater, lush underwater forest, diverse, beautiful, beautiful plant for an aquatic ecologist. Beautiful place to to dive and and snorkel, and those plants and the bottom were covered with invertebrates, but snails were particularly in abundance. Now, those same areas of Trout Lake, or at least a few years ago, they were almost devoid of plants. The plants have been clear-cut by rusty crayfish and invading crayfish species native to more southerly parts of North America, and the snails and other invertebrates, which are snails' or favorite food for these crayfish, have virtually disappeared. So dramatic change in the in the communities in those lakes, and that ecosystems and lots of other work shows changes that that may go up the food chain to fishes.
Marty Martin 28:47
And how is it that I mean, what is it about this crayfish that allows it to have such effects like that?
David Lodge 28:56
That has been a central question invasion biology for for many years, and I think that question is very hard, and I'd almost say maybe ill ill directed at a single species, but it is a useful question, and maybe getting ahead of where you want to go here, it is a good question to ask when you have a lot of data about a lot of species that some have been invaders and some have not been invaders, because that becomes useful. But for any one species, very hard. I can give you some answers to rusty crayfish that include they grow bigger than the native species. They are more aggressive in displacing species from shelter, which leaves the other species more vulnerable to predation. They protect themselves against predation. They have higher feeding rates. So we have a good story based on lots of publications about the differences between. Rusty crayfish and other crayfish, and those are consistent with the patterns that we've seen of displacement of rusty crayfish of other native crayfishes and the ecosystem effects that they've had. But if you ask, could I have predicted that ahead of time? I'm not sure that I could.
Marty Martin 30:20
Yeah. Yeah. Okay. That's fair. That's fair. So
John Drake 30:23
there's a twist to this story, though, right? So Danny Sidlowski and Eric Larson and yourself published a paper looking at different lakes in Vilas County, and in about half of them, the rusty crayfish populations are now collapsing. So like, what's going on there?
David Lodge 30:39
Yeah. It turns out, and this is one reason why I'm continuing this this work in retirement because it's so interesting and important. It turns out it's more than half everywhere, almost everywhere that all the lakes, and we've been sampling many lakes for many years, that we have these long-term data on. There was a boom. The rusty crayfish got very abundant, much more abundant. So total crayfish abundance much more than it ever was with native crayfishes, and we had those effects on the community that I described. And now, in Trout Lake, as an example, starting in about 19 mid 1900, and 80s 90 s. Well, really, no, no, no. Sorry, about about 2000 2000, it started declining, and now the rusty crayfish populations are down. They're still higher than native crayfish populations ever were, but they're getting close to to being extremely low. And we're continuing work to see what kind of if there is restoration of the plants and invertebrates that I described earlier, and we're there. There, there is some of that. We've already seen that in some lakes. And the question is, how long is they going to take? Are the naturally restored or regrowing communities going to be the same? Are they going to be different? Is that boom and bust cycle? Is it a cycle? Is it going to continue, or is this just a one-shot deal? We saw a resurgence of an invasive species, and now it's going to go away.
Marty Martin 32:09
Do you have a favorite hypothesis of the reason for the crash? I think Lindsey Riesinger recently done some stuff on parasites, and then there's body size changes. Right, they're shrinking in some of the lakes.
David Lodge 32:22
Yeah, what? Of course, we're we're we're we're we're mystified, and we're very we're we're we're very interested in knowing the answer to that question. We short answer is we don't know, but the things that we have seen are over time a reduction in in individual body size, average body size, which would make them more vulnerable to predators, for example, and I think a very promising hypothesis is the one that you mentioned by Lindsey Reisinger and her student Cheyenne Stratton, who have recently discovered a a a microsporidian, a fungus parasite, which is new to science. They, they, and their colleagues describe the species. It call it causes what is already known generically as porcelain disease in crayfishes, and the evidence that they've collected, some of some of which is not published yet, and so I want to be be careful not to to speak for Lindsay and her co-authors, but the evidence is consistent with with it as a causal agent. Now, my experience in ecology makes me skeptical of single causes for anything. So I think we have a lot more to learn, but I think this is another example of where completely unexamined interactions that involve parasites and pathogens could be driving the dynamics of of an otherwise sort of keystone species, if you will, or a species that has had dramatic effect. An ecosystem engineer, whatever you want to call the crayfish, it's had a huge impact, and so it it it is a reinforces my sense of ecologists need a lot of humility. We've been studying this system. We and many of my colleagues and students and postdocs for over 40 years. Everything new that we study has contributed and been consistent with an explanation for rusty crayfish being successful and having the impact that they have, and now there's something new that we did not anticipate at all, and it's a species never been described.
Marty Martin 34:51
Do you do you have any sense of whether it has been there for a while, or is this pathogen likely a recent arrival itself?
David Lodge 34:59
Yeah. This is where, in an area where no no one's been studying it, so we don't we don't know. Porcelain disease is studied in other crayfishes. There are closely related microsporidian fungi parasites, so it's it's not a surprise that an organism like this has this impact on crayfish, but never in the in North America and especially in these systems has it been studied.
John Drake 35:27
Okay, so you've told us a little bit about some of your field sites you've worked in the Illinois River, Trout Lake, so forth. But the whole business with the Chicago area waterway system put you in some places that most ecologists never get to go, and I'm talking about the Supreme Court, congressional testimony, federal court as an expert witness. If I'm not mistaken, I think your lab notebooks have been subject to FOIA requests. Can you tell us a little bit about what what that was like?
David Lodge 36:03
Yeah, your question was framed interestingly. Where most where most ecologists don't get to go, I think
John Drake 36:08
get to go. I think you might
David Lodge 36:10
say where most ecologists don't want to go, for for better or worse. Yes, so I think the EDNA that we talked about earlier is a good example of new technologies and the challenges of both testing them, validating them, demonstrating their usefulness for particular applications, and even when that happens, there's an additional hurdle which among people in private enterprise and commercialization efforts and entrepreneurship that is referred to the Valley of Death. How do you get it into practice? There's there's so many ways this can fail, just like there's so many ways biological invasion can fail. There's so many ways that a that a technological infiltration in society can fail, so it was contentious because there's always there's there was vested vested commercial interest, and by vested I don't mean that sound like a an insult. It's just a fact. There's navigation that was important in the canal. There's all sorts of things that are important about the canal, so it was immediately litigious, and I was subpoenaed. I was asked to be an expert witness for the state of Michigan. I declined, not because I didn't want to be paid by anybody. We we we could talk about how wise some of the decisions I made were, and and whether whether I would make the same ones again, but I was subpoenaed as an expert witness, so I was there. I was I was never sued. I was just there to explain the relevance and of environmental DNA. Now I am going to forget the exact timing, but the irony embedded in this was that the Corps of Engineers is the one that had asked us to do this and was paying for us to do this at the same time was the greatest critic of the results because they were they were accountable to the public for what to what to do about it. So I have great sympathy for for the Corps in this, and so we were audited twice. The lab procedures were audited twice with on-site inspections, blind testing, which we welcomed. We absolutely welcomed because by that point it was like, please do whatever you can to satisfy yourself that what the results we're giving you are reliable, because we had confidence they were. And if they're not, if there's something we're doing wrong that we don't recognize, then by all means, let's find out. But the first one was done by EPA, and we passed with flying colors. Those reports are available, but for whatever reason, the corps wasn't satisfied with that with that result, and they independently, shortly thereafter, contracted with Battelle to do a separate audit, including a panel of experts and on-site samples and so forth. We passed that with flying colors. So, and then the lab notebooks were subpoenaed, all that stuff. So, I was in the witness chair in in federal court, Chicago, for five hours under some very unfriendly questioning, and and of course I hadn't been coached very well. Well, hadn't been coached. So, you know that was an interesting experience. The key thing for the future and the use of EDNA is that EDNA was was accepted as evidence, and it passed what lawyers refer to as the Dalbert test, meaning there's no reason legally why EDNA. Not be used more often in applied in a man in management and would survive challenges about its validity. That that doesn't mean that every EDNA result couldn't be isn't mistaken, but it's a technique that is best available science.
John Drake 40:19
I mean that sounds like quite an accomplishment for science, for your group, for your students.
David Lodge 40:27
Yes, I look. We I think we look back on that, and we the the group of us was together not long ago in in Spokane at a meeting, and it it was very difficult. It was very it was it was very challenging, particularly for my younger colleagues, Andy Mayhan, Chris Jirdi, Lindsey, and students who were involved, it was very challenging to be under such scrutiny, and it was so not what most people who go to graduate school and want to be academics signed up for. So it was painful, but I am proud, of course, of what we did. And in general, in an ideal world, these things would get into management after being very carefully vetted and and peer reviewed and and so forth. But we were asked to do it, and the core and and federal agencies and state agencies were making decisions before and during and after we provided results. So decisions were going to be made, and we were asked to provide the results, and we did. And we're very happy, however, to have that transitioned to to federal agencies to continue that monitoring and it continues to this day with the Fish and Wildlife Service doing annual EDNA monitoring of the Chicago area waterway so it's it's proven its value it's still being used
Marty Martin 41:55
yeah there was a there was a line in a government brief in 2010 saying that you had a financial interest in EDNA, you since resolved that. You mentioned just a minute ago that there would have been some things that you'd done differently, but I find like that was an opportunity early where you you could have had a big financial benefit to that, and then you've never done that part. What would have been the things that you would have done differently, maybe to help people understand? Although you know folks have different motives, what could you do? But help them understand, you know, why you guys were doing what you were doing. We
David Lodge 42:28
were doing what we're doing because I mean, in in I'd wanted from the beginning of my career to be doing science that was useful and is immediately useful on as important topics as possible. Well, that was we did that. The I so there have been three or four companies that have been founded by people who learn learned or practiced EDNA in my lab. One of those is still going. That's a company in Europe. I have declined and am and happy to have declined any financial interest or even advisory role for any of those companies because, for the same reason, I declined to be an expert witness for the state of Michigan, I wanted I wanted to be unimpeachable as as a scientist, speaking speaking only from my expertise. I did not want to have conflicts of interest. I did not want to appear to have conflicts of interest. But of course, many people who didn't like the results were trying to find conflicts of interest.
Marty Martin 43:41
Yeah.
John Drake 43:44
So I'm thinking about maybe some of the lessons learned from this episode. One of those that you've talked about, I think, is essentially: don't do this, don't get it into these kind of public policy debates unless you're willing to leave your comfort zone. But then the other one, and you already talked about this today. Is practice humility? Science should inform, and can't be the sole driver of public policy. And in some ways, that second one's a pretty big concession from somebody whose data triggered, you know, roten owning a river. So you know, how do you draw the line on that?
David Lodge 44:23
Yeah, this is obviously complicated, but I think it is a very important topic, and it's gotten more important for scientists, particularly in environmental scientists, in recent years, so I cringe now when I hear people saying policy should be science-based, and that's the point I'm trying to make. Science should not be policy should not be science-based. It should be science-informed. In the canal, and our results alone did not trigger. There was already an electric barrier before, and there had, and that's because there was already policy apparatus at federal and state levels that said, "Hey, it's a policy goal to keep invasive species from migrating from the Mississippi River into the into the Great Lakes, so the policy goal had already been established through the normal democratic processes, and that's a context in which then science and expertise we can come in and say, well, okay, if that's your goal, we have some ideas and some tools that can help you accomplish that, so from that perspective, the Chicago area waterway was an entirely comfortable and appropriate, I would argue, place. Now we did get criticism even from our scientific peers, which is a little painful about doing this before the results were peer reviewed, and I understand that. But I guess I would still, in hindsight, say there was no choice. It was decisions. Decisions were being made, but now further, the decisions then about what to do about that, those are not science based. They're informed by what the risk is, and we have been doing risk assessments of all sorts of species in the Chicago area canal. So our role is to provide the best scientific information and provide the best scientific tools to go about about guiding policy, but the whether to spend many millions or billions of public money to respond to something that is that should not be only science based. That should be that should be based on all the other trade-offs that Democratic policymakers and their agency officials have to have to balance, there are just so many trade-offs. So that's what I mean.
Marty Martin 46:52
Yeah, the one of the papers that we read in preparation for our conversation was a contribution you made to the special issue of Environmental DNA back in 2024, and the last part of that paper I thought was fantastic because it's this really nice advice to scientists trying to you know provide science to policymakers, and then the reverse how policymakers might want to hear and interact with science. We won't ask you to go through that very very long list of suggestions, but what are maybe one piece of each flavor of advice that you you could offer?
David Lodge 47:27
Yeah, I think I'll start with the with the core, just as an example. Don't expect researchers under a cooperative agreement to become a consulting firm. You you you have to understand. Each party has to understand what their strengths and appropriate roles are. Now, from the science side, for for my peers, you you have to be willing to spend the extra time to understand the landscape of policy. Who has what authorities? Who can make what decisions? And you have to be willing to not only spend that time doing it, but listening and understanding with with empathy to the challenges that agency leaders have in trying to decide how to respond to certain information, and all of that requires, on both sides, a level of humility, which, which maybe to put it gently, scientists often do not have.
Marty Martin 48:34
Okay.
John Drake 48:37
And I guess maybe some of this you learned while you were so you chaired the first National Invasive Species Advisory Committee. You're a Jefferson Fellow in the State Department. You were president of the ESA. You know, I'm wondering maybe what else you've learned in those roles that you can share with our listeners.
David Lodge 48:59
Yeah, in 1999, maybe I may have the year wrong. I was the I became the first chair of an of a new invasive species advisory committee, a federal advisory committee. I did that because I had been searching for either. I put my name forward because I'd been searching for ways to accomplish my long-term goal, which was to use science to inform important decisions. And I had been-I'm grateful to the training that I'd gotten in the what was then the Leopold Leadership Training Program-that put me for a week in Washington for training and gave me an opportunity to go visit the Department of Interior offices. Long story short, I ended up to be the first chair, with not a not not maybe an appropriate level of experience, but I but I but I went into that quite confident in my expertise as an internationally known scholar of invasive species. And the first meeting, and every subsequent meeting of that council or the the committee, which had industry representatives, state management representatives, all of whom were very knowledgeable about invasive species from their economic sector and their management mandate, I could not answer any of the questions that they ask, and neither could any of my academic peers because the questions were okay. Yeah, we get this is a problem, and I and other ecologists, the whole discipline was just putting out paper after paper of the impacts of the negative impacts of invasive species and how dire a problem this was, and of course the questions that I got to ask in the advisory committee as was okay, great David, what can we do about it? What are the what are the management interventions? How much would they cost? How effective would they be? In essence, give us a bang for the buck analysis of of decisions that we might make. And as soon as I heard those questions, I was like, "Well, duh! Of of of course that's what you need to know. But unfortunately, nobody in academia is asking those questions.
John Drake 51:26
Well, maybe that's what prompted your following up with economists like Jay Shogren and David Finoff and folks like that.
David Lodge 51:34
I cold called Jay Shogren. I just I just looked through the literature and found who are economists that are working on invasive species, and there were not very many. Now it so happens that Jay Shogren had thought about this, and Jay Shogren is an absolutely stellar economist, and so that is exactly that experience is what gave me my first dose of of humility in the policy world, my wife and others would quickly add that there's plenty more scope for learning more humility. But but that was my first experience where I said, okay, I if if ecologists, if all my peers who are always talking about how terrible public policy is and what are terrible environmental problems we have if we're not asking the right questions. If we want to be useful, so that is that led to a whole series of grants and collaborations involving multiple economists and lots of interaction with managers.
Marty Martin 52:34
Would you say that we as ecologists are doing better now because these exchanges happened a little while ago, and a lot of time passed and a lot of pressure to do better. Are we in a better place than we were 1520 years ago?
David Lodge 52:46
I think we're in a lot better place, but we have a lot farther to go if you're on board with the idea that ecology should be more useful. And so, in my 40-plus years career, there's been a huge change in in this direction. A number of very very good discrete changes. I was advised when I wrote my first NSF proposal, don't say anything about its applications? It's got to be pure ecology. It's got to be cutting-edge community ecology, which I found very discouraging at that point. But of course, I did it. That's the way I wrote the proposal. But I chose topics that actually did have application. I just didn't write about them. Okay, so then we moved from there to NSF. Then a few years later, having a broader impacts mandate that you know maybe got a little bit in that direction. Then ecologists got all excited about communication. We're just not communicating very well, so we need to learn how to communicate. And indeed, it was true that we weren't communicating very well, and that we have gotten better because my graduate students and many others now have training in communicating science to non-scientific disciplines. But that is not a silver bullet. That is just a start. That's just a starting. That's just a starting point. That just means you can have a meaningful conversation with a manager or a policy maker, well, and so often
John Drake 54:24
communications communications training is like a one way street, like almost like marketing. And you were describing this situation in which you're sitting down with colleagues and peers, stakeholders who are approaching the invasive species problem, but with different interests and different challenges, and I'm sort of wondering. Like this is a I think a riff on Marty's question. As a society, what do we need to do so that the science is better informing our public policy?
David Lodge 54:57
Yeah, I have more thoughts. You want to hear on that, because I think the answers, the the meaningful answers have to think about institutional structures, the federal government funding, university structures, and honestly, as painful as it is to be in universities these days, and as painful as it is to be the target of of desired destruction, it seems by the federal government, by the White House, it is an opportunity to rethink some of these things. We are not innocent in creating environments in which we're vulnerable to the kind of criticisms that we're getting. The humanities, in particular, have come in for some very tough criticism, but I believe actually that some of that should be aimed at science also. And so I think now is a great time for academics, young and old, to be thinking about how how did our scientific structures get to be the way they are? Should what is an interesting question be determined and funded only by panels of our closest peers in our disciplinary Areas, my answer to that is no, and I'm not I'm not arguing for an absolute wholesale change, although that may happen no matter what we like or don't like. But I am arguing for empowering the kind of with funding, the kind of science that brings scientists regularly and and intensively in contact with those who have decision making authority, and so can I give you one example? Please, I'm I'm talking too long here. The the absolutely most exciting and most productive experience that I had as a scientist was about a 10-year stretch in which NOAA and EPA, together under the Great Lakes Restoration Initiative, funded a family of projects in that most of which I led, but and all were aimed around understanding or responding to invasive species in the Great Lakes, but to Noah's credit, they mandated, which I welcomed, that we have what they call a management advisory board. So we set up a panel of it's like 20 representatives from state and federal agencies, and we met regularly throughout these projects with that team, and so and provided them regular updates in plain language. Not not that some of them were scientists, some of them very very, but you had to find the common language, you had to understand the the the the questions that they wanted answered, and that we allowed their questions to change our research agendas, that is a critical aspect that is missing from the academy. We are trained as academics to depend only on our own brains. A question is not valid and career building unless it came from you, your own brain, and unless no one's ever asked that question before, whereas the questions that are actually most useful to society are often interdisciplinary, and and require an understanding of a broader landscape outside your own discipline. Your discipline's critical to answering it, but it's not the only thing. So you have to be willing. Part of that humility that somebody earlier is intellectual humility, being willing to say, "What is it you want to know? And of course, in this realm, we were always trying to. We did. We focused then on the questions that were valuable to the managers and intellectually challenging, so that the academics involved could get and and satisfy the imperatives of their own careers. That's the balance that we have to strike. So there should be ways that make that easier. Yeah.
Marty Martin 59:13
Well, I like it. I like it framed that way because it feels now that science in the U.S. is being pushed much more towards, you know, there's no there's no value in doing it unless it's obviously applied, and I can't get on board with that. Although, like you, my whole research career has been shaped around doing things of basic interest, but with you know zoonotic diseases or introduced species things with applied value. I want to turn it on its head because what you just said there at the end, and maybe what came out of this this 10 years of you know science that you were really excited about has your experience in the kind of policy and working with managers realm helped you to do better basic science? Has have questions arose that you wouldn't have done if you never took this path?
David Lodge 59:58
Oh, absolutely. No, it's been. I would. I often say this. This kind of interaction has led to more interesting science that people would describe, if they're so inclined to think in dichotomies, as basic science. But we wouldn't have thought of the questions if we weren't involved in these kinds of broader discussions. So, and I and I don't want to be misunderstood. I am not advocating that that we should do away with basic science, and all science should be applied. Sure, everything we've done on the applied side is built on a foundation of basic science. I mean, this is what Vannevar Bush imagined in post World War II with the endless frontier, recognizing the importance of basic science, but we got so far entrenched in that in the in the academy that it became not just unusual but looked down on to do work that was applied.
John Drake 1:00:58
Well, and I wonder if not only does do we ask different questions, but I wonder if sometimes the science is done better because it actually has to meet those tests in the real world. You actually have your lab notebook scrutinized.
David Lodge 1:01:13
Yeah, absolutely. I mean, I think too often in the sort of academic basic research, everybody sort of knows. No one will say this out loud, but everybody knows. Well, nobody actually cares what we're doing, and so well, you said it. Yeah, yeah, I just said it. But I was not satisfied with that. And so, yes, when you're doing research at this intersection of science and management and policy, man, your results are going to be scrutinized, and you should welcome those skeptical questions.
John Drake 1:01:50
I guess that's part of the humility.
David Lodge 1:01:51
Yeah, that's part of the humility. Now, yeah, it gets a little hard when the questioners may or may not be asking questions in good faith, but that's a whole other. That's a
Marty Martin 1:02:00
different
David Lodge 1:02:01
yeah. That's a different problem.
Marty Martin 1:02:02
Perspective. Okay, so given you know the the current political environment as well as the funding environment, we we can't pass the opportunity, David, to ask you to sort of share your thoughts to that 25 year old starting PhD student. You had 47 graduate students and postdocs, including one of the people that are on this call right now. So, what what kind of what would you like to share?
David Lodge 1:02:29
I am going to repeat something that a postdoctoral advisor said to me that is consistent and really has driven all the kind of things we were just talking about. Jim Kitchell, now deceased, was one of my postdoctor advisors at University of Wisconsin Center for Limnology, and when I was flailing about about what I wanted to do with my life and despairing at the uselessness of ecology, although I wouldn't have put it quite that way, then I. I I was Jim had the patience and willingness to listen to me, and finally he said, "David, just look for the problems that are important to society. And he held up one hand and and and then and look for the intersection, and he interlocked his fingers, and said, "Look at the intersection of those problems with problems that are intellectually challenging and interesting to you, and will be seen as as good problems to work on by your academic peers. He said, "It's not that hard. There's a lot of problems like that, just just find them, and and so for graduate students who want to have their science be useful outside of the academy, and I don't mean to say the exchange of ideas inside the academy is not useful in its own world, but what I'm talking about is useful outside the academy. If a 25-year-old wants that to happen, I would encourage them to think that way. And getting back to an earlier part of our problem about what what the role of science is, do not succumb to the temptation that is quite widespread now to see your career from the beginning as a way to accomplish a policy goal that you have already decided on, and I'm thinking here about aspects of climate change and activism within the academy. So I think this problem of what is the appropriate role of science and a researcher in the academy is one that young scientists need to wrestle with early, and it's much more-it's a much more fraught space than it was when I was growing up, as it were, as a graduate student and young faculty member, because there-it's-it's much more hotly contested now. So I think that's got to be something you think about. Third piece of advice would be, think much earlier than most academics do about how your institutions is is structured, how the universities are structured, and what this is, what what responsibilities we do or don't have to society, because even if you don't think about that, you can end up getting caught because you didn't think about it, and that's where that's where many universities are now.
John Drake 1:05:24
Yeah, that's for sure. Well, that sounds like good advice, David. Have really enjoyed having you on the show, thinking about all of these things. Some of which we did together. Some of which came after I left your group. I'm wondering if there's anything that we didn't ask you that we wish that I'm wondering if there's anything that we didn't ask you that you wish we had.
David Lodge 1:05:47
Now we've covered a lot of ground. I will say one thing that is also good advice, and sort of this goes along with the intellectual humility. Look to bring people into your orbit that are smarter than you are, I was I was successful at that. It wasn't that hard to be successful at that, but one of the people sitting right here, John Drake, is a prime example of that. And so sharing the life of the mind and the the life where the life of the mind can intersect with societal concerns is such a privilege. It's such a privilege to have a life like that as an academic, and it's worth sharing it with people and and helping to cultivate the careers of people who are going to come after you, and I hope solve more problems at the intersection of science and policy and management, than I have.
John Drake 1:06:44
Yeah. Well, you're very kind, David. But you know, I think some of those lessons you impressed upon those of us who are in your lab, and you certainly created an environment where we could think and explore. And I'm teaching a graduate seminar for incoming graduate students this year, and one of the things that I routinely tell them is that graduate school was for me the most exhilarating, the most intellectually exhilarating time of my life, and and I hope that their experience can be as powerful and formative and impactful as mine was.
David Lodge 1:07:19
Well, after that, I should not say anything else anywhere. So thank you, thank you, John. Thank you both.
Marty Martin 1:07:26
Thanks for listening to this episode of Big Biology. If you like what you've heard, tell us on Blue Sky Threads, LinkedIn, Facebook, or Instagram, or just leave a review wherever you get your podcasts. We really do read them all.
John Drake 1:07:37
And if you didn't like something, we want to hear that too. All feedback is good feedback.
Marty Martin 1:07:42
Special thanks to Steve Lane, who manages the website, and Molly McGidd for producing the episode.
John Drake 1:07:46
Thanks also to Caroline Merriman and Cass Biles for social media support, Brianna Longo for our amazing cover art, and Clayton Glasgow, our blogger. Check out his work on our Substack page.
Marty Martin 1:07:57
So public health doesn't support us anymore. I got to cut this out. Big thanks to our Substack and Patreon subscribers, and the National Science Foundation for support. Music in this episode comes
John Drake 1:08:12
from Poddington Bear and Tyrion
Marty Martin 1:08:13
Costello. Thanks for listening, and we'll see you next time on Big Biology. All right, stop that. Let it pull.