Beavers Build Ecosystems Of Resilience

17:21 minutes

a body of water with little dams on it. in the background are trees, but further behind the mountains are slightly barren from wildfire
Beavers, which are only active at dawn and dusk, rest in this mid-pond lodge. While their wetland is surrounded by lush grasses and unscathed evergreens, the nearby hillside shows the damage caused by the 2020 Cameron Peak Fire. Credit: Alex Hager/KUNC

state of science iconThis article is part of The State of Science, a series featuring science stories from public radio stations across the United States. This story by Alex Hager originally appeared on KUNC on September 23, 2021.

Deep in the Cameron Peak burn scar, nestled among charred hills, there’s an oasis of green—an idyllic patch of trickling streams that wind through a lush grass field. Apart from a few scorched branches on the periphery, it’s hard to tell that this particular spot was in the middle of Colorado’s largest-ever wildfire just a year ago.

This wetland was spared thanks to the work of beavers.

The mammals, quite famously, dam up streams to make ponds and a sprawling network of channels. Beavers are clumsy on land, but talented swimmers; so the web of pools and canals lets them find safety anywhere within the meadow.

On a recent visit to that patch of preserved land in Poudre Canyon, ecohydrologist Emily Fairfax emphasized the size of the beavers’ canal network.

“Oh my gosh, I can’t even count them,” she said. “It’s a lot. There’s at least 10 ponds up here that are large enough to see in satellite images. And then between all those ponds is just an absolute spiderweb of canals, many of which are too small for me to see until I’m here on the ground.”

a woman in a blue long sleeve shirt and holding a hiking stick stands in a tall grassy meadow and woodland area
Emily Fairfax, an ecohydrologist who specializes in beavers, sings the praises of the industrious mammals when it comes to their firefighting ability. She has studied their work across the West, and found many examples of beaver wetlands surviving large wildfires. Credit: Alex Hager/KUNC

The very infrastructure that gives beavers safety from predators also helps shield them from wildfire. Their work saturates the ground, creating an abnormally wet patch in the middle of an otherwise dry area. Dams allow the water to pool, and the channels spread it out over a wide swath of valley floor.

Fairfax researches how beavers re-shape the landscapes where they live. Across the West, she’s seen beaver-created wetlands survive wildfires.

“When you’re at this beaver complex,” she said, “it never stops being green. Everything else in the landscape—the hill slopes on either side, they both charred. They lost all their vegetation during this fire. But this spot, it did not. These plants were here last year and they’re still here today.”

burned blackened branches sticking up above tall green grass
The Cameron Peak Fire left some hints that it had burned nearby, like these blackened branches poking out of an otherwise verdant meadow. Credit: Alex Hager/KUNC

Fairfax stands in the middle of a vibrant meadow, with golden-green grass up to her knees. She points to a row of trees about 100 feet away, where the trunks have clearly been singed, but brown needles still cling to branches—a sign of “moderately intense” burning. Just another 100 feet past that, another row of trees has been scorched completely black and free of needles—a telltale indicator of “high intensity” burning.

That gradient, Fairfax said, shows just how effectively the wet beaver meadow held back the fire. These saturated wetlands also serve as a kind of reservoir, slowing down the release of mountain runoff on its way to the places where humans divert and collect it.

“It’s mimicking this critical function that used to be pervasive in these riverscapes,” said Joe Wheaton, a fluvial geomorphologist at Utah State University. “And is that a similar function to what snowpack does or the inefficient movement of water and that leads to healthier riverscapes.”

Just like snow, beaver wetlands hold water for gradual release. That will likely get more important as climate change drives warmer temperatures and less snowfall, making high-mountain water storage even more valuable.

a lush wetland area
A sprawling network of ponds and canals kept the ground saturated even through Colorado’s largest wildfire. Lush grasses persisted even as surrounding hillsides were singed. Credit: Alex Hager/KUNC

The wetland storage system can be bigger than it looks, since more than 80% of the water in beaver complexes is actually underground. But in the grand scheme of things, Wheaton said those systems don’t store that much water.

“Beaver are not going to be the miracle answer,” he said. “You’re not going to create more water at that sort of scale.”

While it won’t make a difference for water managers looking at water from a basin-wide perspective, people are noticing significant changes on a small scale—like when an upstream beaver dam lets a rancher get water a bit longer into the season during a drought year.

a close up of a gnawed branch
Beavers have built a home for themselves in Poudre Canyon. This chewed log is just one small piece of a formidable dam. Behind it, a large pond affords beavers protection from predators. Credit: Alex Hager/KUNC

That isn’t lost on humans, who have tried to reap the benefits of beaver wetlands by creating their own. A budding world of “beaver dam analogs” has seen the strategic creation of human-built dams in an effort to help slow the release of water.

Projects across the West have seen some success, but largely have not been as effective as the real thing.

“The beaver complex and the beaver wetland is so much more than the dam,” Fairfax said. “It’s the channels, it’s the digging, it’s the chewing, it’s the constantly changing the landscape, the dynamics, the flexibility.”

Beavers have millions of years of practice repairing dams and shaping rivers, and that makes them capable water managers.

Fairfax did see a beaver complex serve as a fire break one time in Colorado, but she said it’ll take far more research before we can figure out how effective they are when it comes to slowing down wildfires on a large scale. But for now, these areas are surviving as oases of green in big fires all across the West.

This story is part of ongoing coverage of the Colorado River basin, produced by KUNC in northern Colorado, and supported by the Walton Family Foundation. KUNC is solely responsible for its editorial content.

Stay up to speed with the SciFri Book Club Newsletter!

We'd love to learn more about you! Below are a few demographic questions. This helps us understand how well we're serving/reaching different audiences. All questions are optional.

Segment Guests

Alex Hager

Alex Hager is KUNC’s Water in the West reporter and is based in Fort Collins, Colorado.

Emily Fairfax

Emily Fairfax is an assistant professor of environmental science at California State University Channel Islands in Ventura, California.

Segment Transcript

IRA FLATOW: It’s October, that means to a lot of people Halloween, to me it means the World Series but that’s something else. For the past few years, we’ve been thinking up ways to help you make your Halloween party, your front door, your lawn display, something special, something a bit geekier than your neighbors.

Halloween can be a tinkering geek’s favorite holiday, you got your haunted houses, pumpkin carving, dressing up as your favorite scientist. It’s never too early to get a jump on your souped up decorations. Like, how about turning your pumpkin into a Cylon Jack o’ lantern or 3D printing some candy.

So we thought we’d give you a little bit of time, because we’re going to talk about some geeky things you can make on your own, pretty simple stuff if you’d like to try. Give you a few weeks to get it all working till Halloween rolls around. And here to tell us and help us out with some tips is Windell Oskay, I’m sorry. Windell co-founder of Evil Mad Scientist Laboratories in Sunnyvale, California. Welcome to Science Friday Windell.

WINDELL OSKAY: Thank you. It’s an honor to be here.

IRA FLATOW: Why is Halloween such a good time to make a project?

WINDELL OSKAY: Well, we love to make things and Halloween is that one holiday of the year that is really focused on making cool stuff. And it starts out when you’re a kid and you learn to make your costume and you make decorations for the house. And a lot of other holidays where you might decorate the house, but Halloween is more about making stuff than any of the others. And we really love that.

IRA FLATOW: Let’s get right into some of these things, you have a robotic snapping pumpkin. How do you make that, describe that?

WINDELL OSKAY: This is one of my favorite projects. So what we have is one of those little mini pumpkins about the size of your palm, and you cut it in half such that it’s got a bunch of big, fangely teeth and the top is separate from the bottom. Using a couple of toothpicks, you can make a little hinge such that the top can open. And it sort of opens and closes if you manipulate it by hand. So that’s pretty neat, you have a little pumpkin that has jaws.

But now what we do is we introduce a microcontroller, which is a little tiny microchip that you can program, it’s like a baby computer. And inside that, we put a program, and a little tiny motor, and a couple of LED’s. We put the LED’s up on top to give it a couple of eyes. And put the motor inside, such that it can open up the jaw and close it. Now the cool part about this is you set it on a timer, the motor and the little microcontroller works like a timer.

It sits there for 30 seconds not doing anything. And then the jaw slowly opens and then it snaps shut all at once. And so this is great because you have little kids walk up to this. And they look at it and they see it not doing anything. And then it starts to open the jaw and they start putting their finger towards the mouth and it goes snap.


WINDELL OSKAY: And they jump back but–

IRA FLATOW: No kids are hurt in this?

WINDELL OSKAY: It’s wonderful.


WINDELL OSKAY: Oh, absolutely not. And if they put their fingers in they’d be perfectly safe, it’s just pumpkin teeth. It’s OK.

IRA FLATOW: Where can they see– where can you get the plans on how to build this thing?

WINDELL OSKAY: On our website Evil Mad Scientist Laboratories, it’s evilmadscientist.com and that’s called the Snapple lantern. And we have a bunch of other projects on our website as well that are from very technologically challenging, like that one down to very simple ones you can build at home.

IRA FLATOW: Give me a simple one. How about the LED stuff that you can make.

WINDELL OSKAY: OK, so the LED stuff is simple to somebody like me, that happens to have lots of LEDs lying around at home. And that’s the distinction we need to draw, what is simple versus what is simple to make from what you already have at home.

IRA FLATOW: But you can get all the stuff on the internet, just order it.

WINDELL OSKAY: Oh, absolutely and that’s what we encourage everyone to do. And one of our favorite simple LED projects is called LED Ghosties. So you take a little white LED, actually two little white LEDs, and you hook up each one of them two little lithium coin cell. And you just hook it up directly and it lights up.

Now you take these two and you tape them to the inside of an empty two liter bottle. Now you take that two liter bottle and you hang a piece of white sheet over it and hang it from a string in your yard. Now you have a floating, glowing ghost, that has a sheet but also glowing eyes mysteriously floating somewhere inside of it.

IRA FLATOW: I love that one. 1-800-989-8255 is our number. I’m Ira Flatow. This is Science Friday from NPR, talking with Windell Oskay. So that’s a simple one. I saw also you had a simple one that will certainly be useful for Halloween for lighting up the driveway, or the walkway, or just to your front door, using LEDs also inside a Mason jar. Just very simple.

WINDELL OSKAY: Yeah, so you can do the same thing as the ghosts but if you forget to put the sheet on just put them in a Mason jar. It’s sort of a temporary garden light. Nowadays it’s really easy to get these solar garden lights, they only cost a couple dollars each. So it’s not much reason to use a battery instead of just using the solar light now.

IRA FLATOW: Yeah, but do you have to give a hacker or hobbyist any reason not to do something. I mean they want to do this because they want to do it right.

WINDELL OSKAY: Oh, absolutely.

IRA FLATOW: Yeah. You have hacked– you even hacked into a LEGO figurine, which was quite fascinating. Tell us about that.

WINDELL OSKAY: OK, so there’s this wild coincidence which is that the most common size of LEDs that you can get happens to fit like a glove into the head of a LEGO mini figure. And that’s because the pitch, the little dots on LEGOs, are 5 millimeters across and so are these LEDs. So if you take the head off of a LEGO mini-figure you can just stick an LED inside and light it up.

And we did that, but to make it interesting, you don’t want just a little glowing yellow head with a smile, so what we did is we took the backside of a head actually, so you can’t see the face, and we carved into it. And we carved a little jack-o-lantern face with two triangular eyes and a big toothy smile. And now we have a glowing Jack o’ lantern. And then we take a mini figure, LEGO mini figure, and put that head back on it. And now we have a classic headless horseman, you know pumpkin-head guy that you can make. And that’s pretty easy to make, but it requires a lot of skill with an X-ACTO knife or some very fine motor control in order to actually do that kind of carving.

IRA FLATOW: Yeah, you said on your blog that your fingers were not in good shape, you should have used a drill instead of just the knife.

WINDELL OSKAY: Yeah so I didn’t stab my fingers or anything, that’s the likely hazard when you’re using X-ACTO knife. But I was just holding the little LEGO head so firmly between my fingers, for the hour or two that it took to carve it, that they really hurt afterwards.

IRA FLATOW: You had some really gross looking, and gross in a good way, specimen jars that you made.

WINDELL OSKAY: Yeah, so besides technological projects like LEDs and things, we also do a lot of food making. And we try and do unusual things no one has ever done before. So you know of course our website is Evil Mad Scientist, we are the– want to do things that are evocative of Mad Scientist Laboratories.

And one of those classics is the specimen jars. And sometimes if you go to a museum, you’ll see these old sets of preserved things, some frogs, or something really disgusting removed from some animal’s intestine. And it’s preserved in some yellow sickly liquid and it’s formaldehyde, or alcohol, or something and whatever is inside has been faded and is really nasty.

So we thought, well, let’s do that and it looks just like that except let’s make it dinner. And so for example, one of the things we did is we took some chicken breakfast sausages and we perforated them very carefully with a fork in just the right place so that when they cooked they bent along those perforation lines. And then when they’re cooked, they look just like fingers because they have a couple bends there like knuckles do. We put those in a Mason jar with a little bit of soup. And now you have a legitimate appetizer, but it really looks like you have somebody’s cut off fingers in a jar.

IRA FLATOW: All right we’re going to keep that there. Very appetizing for your party, cut off fingers in a jar. We’re going to come back and talk more with Windell Oskay. So stay with us. We’ll be right back after this break.

This is Science Friday. I’m Ira Flatow talking with Windell Oskay from Evil Mad Scientist Laboratories in Sunnyvale, California. He is chief hacker at the website of the same name. We’re talking about stuff to make for Halloween. Let’s– you talked about those great finger sausages, let’s talk about the Cylon pumpkin you made with a Larson scanner, it sounds like something out of the Big Bang Theory or what is that?

WINDELL OSKAY: OK so Larson scanner is a term that we coined that is named after Glen A. Larson, who’s the producer of the classic TV shows Battlestar Galactica and Knight Rider. Both of which had either the robots or the car with the scanning red light that goes back and forth. And when we wanted to make a Cylon pumpkin, we used that term to describe this set of red lights going back and forth.

And so the idea is you take your pumpkin, you carve it to look like a classic Battlestar Galactica Cylon. And then you put this set of red scanning back and forth lights inside. And there’s a couple of different ways to make that. We’ve talked about making it using some discrete classic electronics like a 555 timer chip or using a microcontroller. And we also make a kit that is easy to solder together and put into your pumpkin.

IRA FLATOW: Also what about the pumpkin, can you make a costume out of a pumpkin, a real pumpkin?

WINDELL OSKAY: You can, but I’m not sure you should. So we went to a Halloween wedding last year and for that we made a– my wife and I made a couple’s costume where we had a pair of pumpkin heads which were actually literal pumpkins that we hollowed out and wore. And this is very challenging to make it– make the walls thin enough that you can bear the weight of it. If the pumpkins big enough to fit over your head, it weighs a lot.

IRA FLATOW: I’ll bet. And if you want to see more of your stuff to make Windell, where should we look on your website?

WINDELL OSKAY: Yes evilmadscientist.com.

IRA FLATOW: evilmadscientist.com Thank you very much for taking the time to be with us today and Happy Halloween.


IRA FLATOW: If you want to see those topics, you can go over to that website.

Copyright © 2021 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/

Meet the Producers and Host

About Kathleen Davis

Kathleen Davis is a producer at Science Friday, which means she spends the week brainstorming, researching, and writing, typically in that order. She’s a big fan of stories related to strange animal facts and dystopian technology.

About Ira Flatow

Ira Flatow is the host and executive producer of Science FridayHis green thumb has revived many an office plant at death’s door.

Explore More