Beavers could be humans’ biggest ally, if we let them

FLORA LICHTMAN: Hey, it’s Flora, and you are listening to Science Friday. Beavers are having a moment.

[AUDIO PLAYBACK]

KING GEORGE: Hey. What’s your name, beaver?

MABEL: Uh, Mabel.

KING GEORGE: You want to live here, you better learn pond rules.

MABEL: What are pond rules?

[ANIMALS GASP]

KING GEORGE: Oh, I am clearing the rest of the day.

[END PLAYBACK]

FLORA LICHTMAN: The new Pixar movie Hoppers is about a girl who, thanks to some far-out technology, is turned into a beaver. Goofiness ensues, of course, but it’s really a movie about humans coexisting with wildlife, particularly oversized rodents capable of reworking landscapes in profound ways. So we wanted to ask, what’s the status of our IRL relationship with beavers? It’s complicated.

And we might want to give it some thought because, according to my next guest, beavers could help humanity out if we let them. Emily Fairfax has spent her career studying these animals, and she’s also the beaver science consultant on the movie Hoppers. She’s based at the University of Minnesota. Emily, welcome back.

EMILY FAIRFAX: Thank you. I’m super happy to be here.

FLORA LICHTMAN: You’ve called beavers a geologic force. What do you mean by that?

EMILY FAIRFAX: Beavers are a geologic force because the scale they operate at, both in space and time, is enormous. Beavers are all over the North American continent. One beaver family is changing and shaping 2 kilometers of a stream, huge territories. And they’ve been doing it for 7 and 1/2 million years. They’ve been modifying things for way longer than people have been building dams or canals or any of our other feats of engineering.

FLORA LICHTMAN: That does seem amazing. I mean, are they good land managers? Like, do you think we should turn over public land to beavers?

EMILY FAIRFAX: They’re great land managers. I think we should work with them on public land. We have our own interests to look out for. We are not beavers. But we could definitely collaborate with them a little bit more seriously. I think a lot of times, we don’t want to work with beavers because they’re pretty chaotic, and we tend to like rules and order and plans.

FLORA LICHTMAN: What do you mean, they’re chaotic?

EMILY FAIRFAX: Well, have you ever seen a beaver pull a permit or draw a blueprint? No. They do not give you any insight as to how they’re going to build. And they change in the moment to respond to their surroundings. They’ll start their dam, the water will flow a little bit different, and they’ll change their plan. And they’ll change it again. And they are just constantly making the landscape incredibly messy. And it’s that messiness that makes it resilient.

FLORA LICHTMAN: Well, yeah. Why should we work with them?

EMILY FAIRFAX: We should work with beavers because we are facing what is probably the biggest challenge of our generation. Climate change is an enormous, difficult thing for us to deal with. And it might be too much to deal with on our own, so we need to work with nature. And we are so lucky that there is another engineer out there that has millions of years of experience doing exactly that– creating stable habitats, surviving climate change, making habitat for other species. We can put our human brains on stuff we’re really good at and then partner with beavers for the things that they’re good at, like creating biodiversity and stopping fires.

FLORA LICHTMAN: Yeah. I wanted to drill down on that, the wildfire resilience. And we covered this on the show a couple years ago in Colorado, where beaver territory did much better in a big wildfire out there. Do you see them as key to wildfire mitigation?

EMILY FAIRFAX: Beavers are definitely key to wildfire mitigation. When you think about what North America used to look like when we had all the beavers of the past– it was 10 times as many as we have now– every single stream was this bright green belt of vegetation. It was wet. It was difficult to burn. It would have been so much harder to have huge, destructive fires back then. So bringing back beavers is about making landscapes that are resilient to fire, not just patches, but entire ecosystems, entire states. They’re outstanding at this.

FLORA LICHTMAN: Besides keeping things wet, do beaver dams have any other remediation effects?

EMILY FAIRFAX: Yeah. So after a fire, one of the big concerns is you’ll have a lot of ash and debris and all sorts of things flow into the water and contaminate it. Beaver wetlands are really good at removing pollution, both post fire and ordinary pollution from the water. They slow it down, it has time to settle to the bottom, and then it gets buried, which doesn’t always sound like the best solution, but we bury a lot of our pollution too, so it’s an acceptable solution for most people.

FLORA LICHTMAN: It’s what we do with most of our trash, right?

EMILY FAIRFAX: Yep.

FLORA LICHTMAN: It’s basically that by slowing down the water, those pollutants then can settle, and then they’re not making it into an aquifer. Is that the idea?

EMILY FAIRFAX: Yeah. There’s a couple of ways that beavers can actually remove the pollution from the water. The first is just by settling it. So when you have heavy metals, like lead and arsenic and cadmium or phosphates, which is an agricultural pollutant and a nutrient, those can latch on to these really fine sediments, sink to the bottom, and just get buried over time. They leave the water column. They’re not going to continue to be in the water that we want to drink and recreate in.

You can also have it be truly removed. So when nitrogen, for example, comes in as nitrates and other agricultural pollutant, that’ll settle to the bottom. But then there’s all sorts of really interesting little microorganisms that live in the bottom of beaver ponds that can process it and turn it back into inert nitrogen gas, send it to the atmosphere in a way that is not going to harm people or plants or cause an algal bloom. So they genuinely removed it in that situation.

FLORA LICHTMAN: I feel like we’re in a pro-beaver bubble here at Science Friday, so please burst it if needed. Because I know it’s not that simple, right? What is the state of the human-beaver relationship today where you work and where you’ve worked in the past?

EMILY FAIRFAX: We’re getting better at living with beavers and acknowledging that beavers are really helpful for us, but we still struggle with them a lot. And I’ve noticed more and more that you’ll find people who are excited about beavers in theory. But then a beaver moves in to their property or place they work, and they’re like, hold on, not here, though. I don’t want it to chew on my trees. It can go chew on someone else’s trees, on public land trees or something.

And that’s a problem because we benefit the most from beavers when we are living alongside of beavers, when we have beavers right on the edges of our towns, helping us remove that pollution from the water, when we have beavers protecting our communities from flood waves or from droughts. So we’re getting better, but I think we need to get more comfortable with being in that chaos and seeing messy wetland environments and acknowledging that that’s both useful for us in nature and also beautiful in its own way.

FLORA LICHTMAN: But also tricky if you’re a farmer or if you have land that needs to be used for a different reason, right?

EMILY FAIRFAX: Absolutely. I think one of the pitfalls we fall into with beavers is asking people to just give up everything to the beaver and like, the beaver now controls my land. I don’t care if my driveway’s underwater. Let it flood out all of my carrots. And that’s not fair. It shouldn’t fall on the individual to lose a lot of financial security. If you are relying on those carrots to bring in your income this year and the beaver floods them, that’s not good.

I would love to see more formal programs to compensate people for when they allow beavers to come back, because they are doing a service for other folks as well. A beaver on my land would help all my downstream neighbors with pollution, and that should be acknowledged financially.

FLORA LICHTMAN: But do you think that it’s easy for humans to relinquish control to a 120-pound rodent?

EMILY FAIRFAX: 110, but absolutely not. In some ways, it’s probably the worst animal for us to have to relinquish control to because we already have this primate brain fear of rodents. And we see them, and we’re like, ugh, it’s bad. I don’t want it to be there. And then nature has basically taken a rodent and made it enormous. And then we also have this primate brain fear of wetlands because we’re not particularly well suited for them. It’s hard for us to navigate them. So nature takes this gigantic rodent and puts it in a wetland. And then it’s the biggest prank for it to be like, surprise, here’s your number one ally. Make friends.

FLORA LICHTMAN: This does feel like a Pixar movie.

EMILY FAIRFAX: Yeah. I think there’s a reason they picked beavers.

FLORA LICHTMAN: OK. Obviously, Hoppers is not a documentary. So tell me about this gig as the science consultant. What role did you play?

EMILY FAIRFAX: Working with Pixar was truly a once in a lifetime experience. And I did a lot of things with them. Some of them were very familiar. I gave talks about beavers. I do that all the time. That’s old news. But other things were a little bit different. I was taking teams of artists out into the field and showing them beaver ponds firsthand. I was watching early versions of the film when they were still hand-drawn sketches and providing feedback on, is this scientifically accurate, yes or no? And if no, does it matter?

FLORA LICHTMAN: Give me an example of a sketch that you had to give feedback on. Like, the teeth were too big? What did you have to worry about?

EMILY FAIRFAX: The size of the beavers was actually one thing. We have a tendency to imagine beavers as quite small, like bunnies or muskrats, but a beaver is 40 to 110 pounds as an adult. So making sure that they are properly sized without looking monstrous on the screen was one of the things we talked about. Keeping the teeth orange was important, making sure that they were appropriately round and awkward and cumbersome, because that’s what beavers are. We don’t need to make them something they’re not.

FLORA LICHTMAN: OK. So you made this distinction, is it factually accurate, and does it matter? When does it matter for a movie like Hoppers?

EMILY FAIRFAX: It matters a lot if something is accurate if what you’re saying has potential to change how people behave towards beavers and not a good way. So what I really didn’t want them to show was beavers eating fish. Beavers do not eat fish. The media has already done us dirty on this with The Lion, the Witch, and the Wardrobe. And that beaver family serves up a big old plate of fish.

And that has persisted in people’s minds. A lot of people reference watching that movie as the reason they think that beavers eat fish. And then we manage beavers to protect the fish, which doesn’t make sense, because they don’t eat the fish. So we wanted to avoid–

FLORA LICHTMAN: What do they eat?

EMILY FAIRFAX: –the kind of myths– oh. Beavers eat plants. They eat the bark off of trees. They eat pondweeds, lilies, cattails, grasses, sedges, fruits. They love a good sweet potato in a rehab situation. But they certainly don’t eat meat.

FLORA LICHTMAN: They’re vegetarians.

EMILY FAIRFAX: Entirely.

FLORA LICHTMAN: Wow. OK. That’s an aha. Are there any other examples of misconceptions you wanted to make sure didn’t get perpetuated in this movie?

EMILY FAIRFAX: Yeah. One of the big ones was that if you have one beaver, you’re suddenly going to have a million beavers on your property. And I think the movie actually played around with this one a little bit, because you see the beavers in the movie, and there are a lot in one space. And that’s not accurate. Beavers are very territorial. They just like to hang out with their families. But I think the movie did a good job of showing it wasn’t natural to have all those animals packed into that really small space. That was something they were doing out of stress because we couldn’t coexist with them very well.

FLORA LICHTMAN: Do you feel like beavers are going to have their moment because of this movie? Do you see that happening?

EMILY FAIRFAX: I do, especially with kids. I think that a lot of people will never get the chance to encounter beavers when they’re growing up. We are still only at 10% of the historic population. You really have to try to see them in some parts of the country. And now here they are in front of everyone on the big screen or on your small screen at home. And kids can understand this is a real animal. It’s more than just something we learn about in history lessons about the fur trade. And wow, it can really help us. Look at all the things that helped us with. Especially for kids in fire-prone landscapes, I think that there’s a strong message of, we need help, and beavers can provide it.

FLORA LICHTMAN: What about the animators you worked with? What facts wowed them or changed their idea of what they were making?

EMILY FAIRFAX: That’s a great question. They were so great about listening to all of my rants and facts about beavers. We did beaver trivia at their holiday party. They really liked just the basic beaver biology, just the idea that beavers are enormous and that beavers will eat their own poop once. That was one that they just really thought was funny and tried to find a way to work it into the movie, but it didn’t fit, understandably.

They thought that the way beavers interacted with each other was extremely cute, the way that beavers sit on their tails like a little chair. That was a fun fact. They were like, no, they don’t. That’s ridiculous. I was like, no, they do. And that made it into the movie, that beavers sit on their tails. But Mabel, the fake beaver, she puts her tail out behind her when she sits down as a tell that she is not a real beaver. She doesn’t know their behaviors.

FLORA LICHTMAN: Emily, what brought you to beavers in the first place?

EMILY FAIRFAX: I first got interested in beavers seriously by watching a documentary about beavers. I was on a totally different career path and struggling to find out what I was going to do. I wasn’t happy in the direction I was going and just happened to turn on the TV and see a PBS documentary called Leave it to Beavers. And I was so hooked. I couldn’t stop thinking about it. And I trusted my gut and said, I’m going to go to grad school and study beavers. I will find a job later that could potentially work with this path. But right now, I just need to understand this animal. So maybe this Pixar movie will be someone else’s launch point, like that documentary was for me.

FLORA LICHTMAN: Someone else’s Leave it to Beavers. Were you not in science? This is an aside, but what were you doing? How big of a pivot was it?

EMILY FAIRFAX: I was a weapons engineer, so it was a pretty big pivot. Yeah. Yep. I was working on weapons and had top-secret clearance to work on bombs and was applying my science that way. And I had student loans to pay, and that’s one thing that that path is really good for. But very quickly into it, I realized I just couldn’t. I needed to do something that felt more aligned with my goals and my values. And I had always loved wetlands. I just didn’t know there were jobs in wetlands. And that documentary let me see, you know what? These people study wetlands. Maybe I can too.

FLORA LICHTMAN: Wow, what an amazing story. And I wonder if your weapons military framework or background has allowed you to understand beavers in a different way.

EMILY FAIRFAX: No, you’re spot on. I was a weapon systems engineer, so systems engineering was my domain. And I think that that has lent itself really well to beavers, because whenever you’re looking at a system, whether that is something designed for destruction or something designed for restoration, there’s a lot of pieces from a lot of disciplines. And you have to learn to work with the physicists and the chemists and the biologists and the economists. And all of those people are part of the system and understanding it. And that was exactly the same situation with beavers. I just liked the center of the system a lot more.

FLORA LICHTMAN: How often in real life do we get a happy ending between beavers and humans living together?

EMILY FAIRFAX: We get a lot more happy endings with beavers now than we did five years ago and way more than we did 10 years ago or 20 years ago. We’re finally appreciating them. I’m having so many more people ask me, where can I go see the nearest beaver? I saw Hoppers, and my kid wants to see real beavers. Where do we go? And just that openness, I think, is a really critical step.

We have a lot of opportunity to grow, though, because for every situation that resolves really well, there’s quite a few more that don’t. And I know that we just need to keep pushing and reminding people this beaver is important. It’s nature. It’s a little chaotic. Give it some time. We can be quite impatient. Like, when beavers are out trying to find their new territory, the little dispersing juveniles once a year, if one just passes through someone’s property, sometimes they freak out and they say, oh, shoot, there’s a beaver here. I need a trapper to get rid of it.

The beaver would have left on its own within a week or two, but we’re just so impatient. If we see something that feels wrong, it has to be solved right now instead of waiting to see what happens.

FLORA LICHTMAN: You know what’s weird? Emily, I feel like we’re a lot like beavers. We are chaotic, and we do remake the landscape to our own specifications. That’s our whole jam. We have a lot in common.

EMILY FAIRFAX: We have a lot in common with beavers. I frequently joke that the only creature more stubborn than humans is beavers. And it sure doesn’t do us any favors when both of us want to live right next to the river and we have a really different picture of what that should look like. But I think it’s also good, because sometimes it’s hard for people to relate to animals or to understand them or to have empathy for them.

But when people learn about beavers and learn that they have families, and they just want to make a safe home for their family, and they are very social, and they’re very smart, and they’re little engineers, and they’re kind of chaotic, and they get the zoomies, it starts to feel a lot more relatable. And it makes us pause and think, well, I get that feeling. Maybe I shouldn’t remove this beaver or trap it out.

FLORA LICHTMAN: Emily Fairfax studies beavers at the University of Minnesota, and she was also the science consultant for the new movie, Hoppers. After the break, when the rubber meets the river on beaver relations, a new effort in Oregon to coexist. Stay with us.

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FLORA LICHTMAN: Up next, we’re headed to Corvallis, Oregon, also home of Oregon State University– go, Beavs– where people are trying out a solution to help beavers and people coexist. Joining me now to talk about it is Zac Ziegler, a reporter at KLCC Public Radio in Oregon. Hey, Zac.

ZAC ZIEGLER: Hey. How’s it going?

FLORA LICHTMAN: OK. Tell me about this beaver situation outside of Corvallis.

ZAC ZIEGLER: Yeah. So this is in an area called the Bald Hill Natural Area. There’s a popular multi-use path there that, starting in 2023, there had been some issues with the little flooding because some beavers had decided to move in on a creek. And well, that led some nonprofits and local governments to search for a way to get a little coexistence between the two.

FLORA LICHTMAN: What was the solution to this problem?

ZAC ZIEGLER: So the solution was what’s called a notch exclusion fence. And it seems like such a simple solution that it’s kind of amazing it hadn’t been tried here in the Beaver State before this. All that they really did was cut a little hole like a notch in the beaver dam and put a fence around it. And they cut that notch deep enough to where it got things to the level that they wanted so this nice, easily accessed path wouldn’t flood.

FLORA LICHTMAN: Can beavers fix the patch? Is this a long-term solution?

ZAC ZIEGLER: So this is going to be a pretty long-term solution. The fencing that is put around it, it’s like chain link or chicken wire. And it does a pretty good job of letting anything like small aquatic life that lives in the creek that this is on, let it pass through while the beavers seem to not be trying to build around it. They seem to be just kind of accepting its presence there and rolling with it.

FLORA LICHTMAN: Can you take me there? Give me a sense of what this part of Oregon is like.

ZAC ZIEGLER: Yeah, yeah. So it’s a really lovely area, as you would expect in a natural use area. And as you would expect in Oregon and the Willamette Valley, it’s very green. I got to see ducks and some salamanders and some other birds and just a variety of wildlife that had moved in. It was really nice, really just kind of a lush green area that now has this almost marshy habitat that is really healthy for the area.

FLORA LICHTMAN: And this wildlife moved in because of this new wetland?

ZAC ZIEGLER: Yeah. Once the beavers had built the habitat, we now saw ducks moving into the area and other things. And the folks that I spoke with there, people from the group that had done a lot of the work on this, they said, yeah, these animals weren’t here to the extent they were before because this was just a little tiny creek. And now it’s a nice little marshland that is allowing for the habitat that is traditionally there in Oregon from beavers.

FLORA LICHTMAN: Zac Ziegler, reporter at KLCC Public Radio in Oregon.

ZAC ZIEGLER: Thank you.

FLORA LICHTMAN: This episode was produced by Kathleen Davis. And if you have a large rodent you’d like to know more about, give us a call, 877-4-SCIFRI. We love hearing from you. And don’t forget to rate and review the podcast if you like it. You just look for the stars, and you press 5. We’ll catch you next time. I’m Flora Lichtman.

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