States Battle Over Solutions To Invading Fish The U.S. Supreme Court has denied the state of Michigan's request for an injunction that would have closed two boat locks leading to Lake Michigan. The request was aimed at blocking invasive carp from entering the Great Lakes. Environmental lawyer Nicholas Schroeck explains why the state of Illinois, city of Chicago and local shipping interests were against the proposed closure.
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States Battle Over Solutions To Invading Fish

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States Battle Over Solutions To Invading Fish

States Battle Over Solutions To Invading Fish

States Battle Over Solutions To Invading Fish

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

The U.S. Supreme Court has denied the state of Michigan's request for an injunction that would have closed two boat locks leading to Lake Michigan. The request was aimed at blocking invasive carp from entering the Great Lakes. Environmental lawyer Nicholas Schroeck explains why the state of Illinois, city of Chicago and local shipping interests were against the proposed closure.


Next, a battle between the states over water trade and an invading fish.

Yeah, last week the U.S. Supreme Court turned down a request for an injunction that would have closed two locks, you know, the kinds that hold water - and two locks leading to Lake Michigan. The request by the state of Michigan was aimed at blocking invasion Asian carp from entering the Great Lakes.

Now, opponents of the lock closure cited a potential large cost to the shipping industry. Now, of course, if you close the locks down, you can't move ships through them, as well as the uncertainty of being able to prevent the carp's movements via the lock closures.

A large case still up to - for consideration by the court, seeks to reopen 90-year-old decisions, a 90-year-old decision involving diversion of water from the Great Lakes to the Mississippi River. It's very complicated.

And joining me now to help us walk through the issues is Nicholas Schroeck. He's executive director of the Great Lakes Environmental Law Center and an adjunct professor at Wayne State University Law School in Detroit.

Welcome to the program.

Mr. NICHOLAS SCHROECK (Great Lakes Environmental Law Center): Thanks. Good to be with you.

FLATOW: Seems like they've been arguing over this for, what, 90 years now?

(Soundbite of laughter)

Mr. SCHROECK: Yeah. The diversion itself has been contentious since - well, even before that, since back in the late 1800s. Ever since they decided to change the flow of the Chicago River, reverse it and send it towards the Mississippi, this has been involved in mitigation.

FLATOW: Well, let's talk about the Supreme Court has denied this request to order that Chicago lock those locks up in an attempt to keep the carp from colonizing Lake Michigan.

Mr. SCHROECK: Right. So Michigan had requested, actually twice - this was their second request for a preliminary injunction to close that series of locks.

FLATOW: Right.

Mr. SCHROECK: And the Supreme Court didn't really give us much to go on. They just denied it in a one sentence order, saying that the motion for the preliminary injunction was denied.

And the reason Michigan was seeking to do this is because these carp right now, there's been environmental DNA detected on the lakeward side of an electronic barrier that's down on the bottom of this canal that's meant to keep the carp from swimming towards Lake Michigan.


Mr. SCHROECK: But DNA has been found on the other side of that. And so Michigan and certainly the other states around the Great Lakes are very concerned that once those carp get into Lake Michigan, they're gonna cause all sorts of problems.

FLATOW: So they haven't the fish, but they found DNA. Well, how do you find DNA? What does that mean?

(Soundbite of laughter)

Mr. SCHROECK: Well, this is a relatively new test that's been developed by some leading water scientists, including Dr. David Lodge from Notre Dame. And what they do is they actually sample the water and they - and, again, I'm not a biologist so I'll try and do the best I can here. But they sample the water and they look for solids that are - that have come from the fish.

So - and then they detect those traces. And then what the scientists tell us is that that means a fish has been in that area within the last day or two. So when we get positive hits on this environmental DNA in Lake Michigan, it's very concerning because we hear that that means a fish have likely been in the last couple of days.

FLATOW: Right.

Mr. SCHROECK: Now, they haven't found live fish, which maybe because it's been the winter, there's been ice cover and they've been very limited in their efforts do electrofishing and netting and that type of thing.

FLATOW: Right.

Mr. SCHROECK: So there very well may be fish already in Lake Michigan. We just don't know.

FLATOW: We're talking about fish in Lake Michigan this hour on SCIENCE FRIDAY from NPR.

I'm Ira Flatow, talking with Nick Schroeck.

So where do we go from here? What's - you say they're - they have some electrical barriers...

Mr. SCHROECK: Right.

FLATOW: the lock, trying to keep the fish out. Maybe they are working, maybe they're not working. And what else can they do?

Mr. SCHROECK: Right. Well, there's a series of management steps that - and to be fair to the federal government, they have drafted a framework or response plan that they're working on. So they've actually poisoned a stretch of this canal already back in December with a toxin called rotenone. And they killed off all the fish in the river and - just in case any Asian carp had gotten on the lakeward side of that electronic barrier.

FLATOW: It's like using a shotgun, isn't it?

Mr. SCHROECK: Exactly. It's not the most targeted approach and certainly I'm never an advocate of poisoning waterways to deal with the problem. And they can also put in different types of weirs and nets to try and catch any carp that may be on the other side of that barrier. So all of those tools are in this management strategy. But what Michigan was requesting was that they also close these physical lock structures to also help inhibit the migration of these carp towards the lake.

FLATOW: Mm-hmm.

Mr. SCHROECK: So while the Supreme Court denied that injunction, they have not yet decided on this older diversion case, which goes back 90 years. And that's what actually regulates the amount of water that is allowed to flow through that canal and out into the Mississippi. So the Supreme Court will actually be reading those briefs and deciding, one way or another, on whether or not to open up that case on April 16th.

FLATOW: Wow. So because if you decided for that reason, you've decided it for the second reason.

Mr. SCHROECK: Right.

(Soundbite of laughter)

Mr. SCHROECK: Yeah. Yeah. And that's - and so the argument that Michigan and the other states - and I should point out that other than Illinois, all of the other Great Lakes states have chimed in and said they want the Supreme Court to open up this case and take a look at it, and appoint what's called a special master.

FLATOW: Right. Yeah. That's somebody knows everything about everything, right?

Mr. SCHROECK: Right.

FLATOW: We've seen them in all kinds of electronics cases, things like the computers, they have a special master.

Mr. SCHROECK: Exactly. So you bring in what's thought to be a nonpartisan person, you know, someone who doesn't have any skin in this game, bring him in from probably another region on the country...

FLATOW: Right.

Mr. SCHROECK: ...but certainly someone who's well-versed in water law...

FLATOW: Right.

Mr. SCHROECK: ...and have him look at the issue. Now, in the meantime, there's just the concern that while we're waiting and while we're waiting for the court to decide on this case, the carp are still moving. I mean, they don't - they certainly don't wait for a signal one way or the other to continue their migration towards the lake.

FLATOW: And...

Mr. SCHROECK: Go ahead.

FLATOW: No, go ahead, because the fish will find a way. If they can, they will find a way, won't they?

Mr. SCHROECK: Exactly. And we've seen that this is a very adaptive fish. They have colonized. Imagine back in the 1970s, these fish were released due to flooding down in Arkansas and Mississippi from fish farms and wastewater treatment plants.

FLATOW: Right.

Mr. SCHROECK: They actually flooded out of their ponds into the Mississippi, and then they've migrated all that way north. And so right now they're literally knocking on the door of the Great Lakes. And of course they wouldn't be able to get there were it not for this artificial connection between Lake Michigan and the Mississippi River.

FLATOW: And so the weather, cold weather - Chicago is not going stop these fish.

Mr. SCHROECK: It doesn't look like it. I mean, they've been living now in Illinois for quite some time. And it appears that they are able to adapt and that they're going to spawn and reproduce, which is why - you know, once invasive species get into the Great Lakes, and we've seen this with zebra mussels and sea lampreys...

FLATOW: Right.

Mr. SCHROECK: ...once they get into the lakes, we really can't eradicate them. You can try and control them, spend millions of millions of dollars trying to control them, but really to get rid of them, it's almost impossible. So it's much better to think of a preventive...

FLATOW: Mm-hmm.

Mr. SCHROECK: ...approach in trying to keep them out.

FLATOW: Alright. Nick, stay with us. We're going to take a short break. Talking with Nick Schroeck, executive director of the Great Lakes Environmental Law Center and professor at Wayne State. Our number, 1-800-989-8255. Maybe some folks from Chicago would like to hear from you about what you think or up there in the Great Lakes area. Or you can send us a tweet @scifri at S-C-I F-R-I. So stay with us, we'll be right back.

(Soundbite of music)

FLATOW: You're listening to SCIENCE FRIDAY from NPR. I'm Ira Flatow. We're talking with Nicholas Schroeck about the Asian carp, keeping the Asian carp invasion coming from the Great Lakes. Our number, 1-800-989-8255. Larry in Hooks, Texas. Hi. Welcome to SCIENCE FRIDAY.

LARRY (Caller): Hi.

FLATOW: Hi, there.

LARRY: It seems to be an industry that's willing to keep the locks open and also it's an industry that wants to fish the bluefin tuna out of existence. How about we just get together and find a delicacy made with the Asian carp.


LARRY: (Unintelligible) the industry fish them out of existence where we're at.

FLATOW: Yeah. Nick, are they good eatin'? Can you fish them?

Mr. SCHROECK: You know, they certainly are edible and people do eat them. And in fact, certain cultures actually really enjoy the fish. The market hasn't been large enough to this point to actually get enough of the carp out of there. I mean, they reproduce so effectively and they're such voracious eaters that they've actually taken over 80 percent of the biomass in parts of the Illinois River. So it's a lot of carp, a lot of fish.

But you're actually right. I mean, I've heard that there's a guy in New Orleans who has some sort of Cajun recipe for these carp. And that may be a way to market it and help deal with the problem. But unfortunately, commercial fishing - if the carp get into the Great Lakes, it would wipe out our sport fishery and commercial fishery there. So we really wouldn't have a net gain. It would just be a loss and then trying to control the problem.

FLATOW: Larry, you think it's better than a catfish?

LARRY: I don't know.

FLATO: Yeah.

LARRY: I do know that the Coho are great on the Great Lakes because I fish them, and I would hate to see that go away for a carp.

FLATOW: I think that's probably, you know, what they're thinking up there, Nick, right?

Mr. SCHROECK: Right. Absolutely. It's just - these carp, they would - the fear is that they're going to out-compete all of the native fish populations, and, in fact, they'll disrupt the food chain, because they eat much smaller organisms, which then the feeder fish would die off, which would feed the bigger sport fish around the Great Lakes. So that's the concern. And I think it's valid based on what we've seen so far on the river systems.

FLATOW: Are they - is there any other way to move the traffic through the locks without opening - you know, it sounds silly, can you lift ships over the locks instead of letting them through the normal way?

Mr. SCHROECK: Yeah. That's actually - the Great Lakes Commission, a group that - of all the Great Lakes states, that gets together and works on water policy, they've actually discussed using a type of hoist system where you would actually drive a ship or a barge up to this hoist, it would lift it up over a physical barrier and drop it on the other side. I understand it was pretty common in parts of Europe - in the Netherlands, for instance, where you have a lot of...

FLATOW: Right.

Mr. SCHROECK: ...dams and control structures. The other thing, though, Ira, is there's been studies that have looked at switching the mode of transportation. It's a relatively small stretch of river and you could move that cargo by rail freight or perhaps trucking. So that's another thing to look at, and maybe that it's time to look at different ways of moving cargo around that area of Illinois.

FLATOW: But you know that - you know, we've seen invasive species in all kinds of lakes and rivers and they attach themselves to - they wind up in the bilge water, the eggs go inside, right, or they have - you have so many algae that sticks to rudders and all kind of things. They find their way into the other waterway.

Mr. SCHROECK: Well, and that's the other concern. This area of the country, it's pretty flat and there's a lot of rivers and drainage ditches and that type of thing right near each other. So where this canal is that we're concerned about, the Des Plaines River, a large river, is right near this canal and in some areas only a few yards apart. So if there's any major flooding...

FLATOW: Right.

Mr. SCHROECK: ...we would also be worried about carp coming in. And of course there's other pathways in Indiana where the carp might get in. So it really is - what we really need is comprehensive federal legislation dealing with invasive species. Because if we stop them at one point of entry, there's always another vector that they may get in. You're absolutely right.

FLATOW: And what would that - what kind of a legislation would that would it set up to deal with something like that?

Mr. SCHROECK: Well, there's been some proposals out of the Transportation and Infrastructure Committee in the House looking at how we deal with international shipping but also dealing with aquariums, aquaculture, that type of thing. It really needs to be comprehensive because, of course, as we've seen with other environmental regulations, if you have one state that has really good laws, if your neighboring state has poor laws, well, that's - it's not going to really work because pollution doesn't really know borders, just like invasive species don't know borders. So that's really what we need, is a comprehensive national program to deal with aquatic invasive species.


Mr. SCHROECK: And there's been some discussion about that. It's unfortunately been stalled in the last Congress.

FLATOW: As Jeff Goldblum said in "Jurassic Park," nature will out some... (unintelligible)

(Soundbite of laughter)

Mr. SCHROECK: Absolutely.

FLATOW: All right. Thank you for taking time to be with us. And we'll be following this and see what happens with the Supreme Court.

Mr. SCHROECK: Thanks very much for having me.

FLATOW: You're welcome. Nicholas Schroeck is executive director of the Great Lakes Environmental Law Center and adjunct professor at Wayne State University Law School in Detroit.

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