Beaver Believer: How Massive Rodents Could Restore Landscapes and Ecosystems At Scale

I first heard about the book Eager: The Surprising Secret Life of Beavers and Why They Matter in a conversation with Brock Dolman, the co-director of the WATER Institute at the Occidental Arts and Ecology Center. Brock was telling me, in his inimitable way, about OAEC’s Bring Back the Beaver campaign, a growing endeavor to “re-beaver” California. I considered myself fairly well informed on many environmental and conservation issues but, in all honesty, I had never really thought of beavers as a species that needed our attention as compared to the vast list of threatened and endangered species upon whose collective necks humanity has pressed its foot. Beavers had come up while we’d been talking about ecological restoration efforts and Brock told me to “Go read EAGER.” So I did – and I joined the ranks of the “beaver believers” in short order.  

Written by the journalist Ben Goldfarb, EAGER is a brilliantly researched and tremendously accessible dive into the past, present and potential future of the American Beaver, Castor canadensis. Goldfarb explores the historical extent of beavers in North America and the dramatic transformation of the entire landscape as a result of the truly barbaric fur trade that led to colonization of the interior of the continent and the near extinction of the species. As one of nature’s most tenacious and dynamic engineers, the ecological role that beavers have historically played in North America (and Europe, for that matter) is mind-boggling. Upon reading the volume, I found that my entire contemporary understanding of the continent received a major system upgrade, the result of a crash course in historical ecology. Just a taste: Goldfarb reports that pre-contact North America beaver dams may have impounded an additional 230,000+ square miles of water (think Arizona + Nevada for reference) via an estimated 150-250 million ponds. Read an excerpt of EAGER here.

EAGER manages to simultaneously expose how little we collectively understand about the ecological history of our landscapes while highlighting truly inspirational people and leading-edge projects that are working to partner with our rodent colleagues, including Dolman and the Bring Back the Beaver campaign as well as dozens of other efforts around the country. I spoke with Ben Goldfarb prior to the 2021 Bioneers Conference, where he participated in a session on the topic of Biophilic Infrastructure.

[This interview has been lightly edited for clarity and length]

TEO: How did you find yourself writing a book about beavers?

BEN: I always had kind of an affinity for them. I grew up in New York and spent a lot of time in the Catskills and Adirondacks, which are some of the more beavery places on the East Coast, and saw them while hiking, fishing and camping. But I think my conversion to the cult of beaver belief occurred in 2014. I was living in Seattle as an environmental journalist, and I got a flyer to attend a “beaver workshop.” It sounded like it might be a story, so I went to the workshop.

It was a profound, quasi-religious conversion experience where one person after another – hydrologists and ecologists and fish biologists and fluvial geomorphologists – got up and told their story about why beavers are so crucial for conservation and carbon sequestration, for storing water in the face of droughts and creating firebreaks on the landscape. I started to realize that this rodent that I’d been around all of my life was not just a huge critter, it was actually one of the primary movers and shakers in North American ecosystems. It was really that workshop and some of the stories that spun out of that that really got me thinking about beavers as a profound environmental force.

TEO: What is the difference between the beaver population in North America today and pre-contact, before the fur trade really started up? And do we know what the result has been on the landscape?

BEN: What I attempt to do in the book is to figure out what North America looked like with its full complement of several hundred million beavers. It’s really hard to know, but there’s no question that this was once a much bluer, wetter, greener, lusher place than it is today. It’s amazing to read trappers’ accounts of crossing Southeast Wyoming, which today is basically desert, and finding these largely beaver-created and maintained marshes, full of waterfowl. 

One of the hard things to communicate is that beavers are not an endangered species. We’ve got maybe 10 to 15 million of them in North America, so they’re actually abundant. But they’re just a tiny fraction of their historic abundance, obviously. We’ve got them in every state, but we don’t have them in every watershed or even close to it, where they historically existed.

We have got a lot of laws that are geared toward recovering endangered species, but we don’t really have any laws that are geared toward bringing a common species back to its historical ubiquity, and that’s really where we need to get with beavers. We’ll never have 400 million beavers again, but there’s certainly a lot of room for them today that they’re currently not able to take advantage of because they’re trapped out every time a conflict occurs. 

TEO: Beavers are seen by some as a pathway towards restoring components of the ecological functions of North American landscapes. One of the complexities of ecological restoration is answering the question, “What (or When) are you restoring to?” Climate change obviously makes that even more daunting. Do you have a sense of the restoration potential for beavers and what the ecological implications of “re-beavering” could be?

BEN: It’s a great question. Certainly there’s a technical answer to that, which is that there are all these beaver GIS modeling tools where you can go to your chosen watershed and say there are X-kilometers of available beaver habitat here, or 36% of the watershed is suitable for beavers. However, there are a couple bigger challenges in beaver restoration. 

The first is that when we wiped out hundreds of millions of beavers, we also changed the landscape and the waterscape in ways that made it harder for beavers to return to those places. When you eliminate a beaver, you lose all those beaver-built speed bumps, those dams that are pushing water out onto the flood plain and slowing down flows. There’s nothing checking water velocity. You often get erosion and fission and the stream just erodes to bedrock, and you end up with a firehose-like stream channel that’s a very hard place for a beaver to build a dam. We actually lost a lot of the potential beaver carrying capacity as a result of trapping. 

That’s where tools like beaver dam analogues come in, building these little starter beaver dams that the genuine rodents can come in and build off of, and use to establish in a given watershed where they might not be able to otherwise. There’s a lot we can do mechanically to encourage beaver reestablishment and increase the restoration potential.

The second really important thing – I write about this in the book a lot, of course – is just reconfiguring our historical imagination or conception of what a healthy riverscape looks like. I think we have this idea that a healthy stream is a free-flowing, fast moving, gravel-bottomed thing that you would see in Field and Stream magazine when in reality so many of our streams were incredibly complex and multi-threaded. In some places they were more like very swampy marshes with dead and dying trees everywhere, and the bottom was mucky and it smelled kind of funky. I don’t think that is most people’s conception of a healthy streamscape, but we know, of course, because of beavers, that was historically more rule than exception in North America, and Europe as well.

Bringing back beavers is a technical challenge, but it’s also an imaginative challenge in that, again, we have to reconfigure our historical understanding of what a healthy stream is. 

TEO: Beyond wanting to return to a more wild and healthy landscape, what are the practical benefits? I assume there are benefits to both biodiversity as well as the ecosystem service side of things. 

Ben Goldfarb

BEN: I think you’re right. There are benefits to other species and then there are benefits to us humans. For other species, just name an organism and it probably benefits from beaver habitat, especially in the American West where water is life. Wetlands cover 2% of land area and support 80% of biodiversity. 

Here in Washington where I live, the flagship species that guides most management is salmon, and beavers create these fabulous little juvenile salmon-rearing refuges. That slow-water habitat that beavers build is perfect rearing conditions for young salmon. The salmon are the primary beneficiary, at least from a management standpoint. I think the importance of restoring salmon habitat is what has catalyzed a lot of interest in beavers in the Northwest over the last 15 years or so and beavers are really integral to that. 

Most species of waterfowl do well in the presence of beavers. Actually a lot of songbirds, warblers and flycatchers and the like. Woodpeckers, of course, love the dead trees that beavers create. Other aquatic mammals – mink, muskrat, moose, otter – are all big beaver beneficiaries, and amphibians, of course. The list of organisms that benefit from beavers is just basically a list of organisms that live in North America.

For us humans, the list is just as long. Water storage is a huge one, especially here in Washington state. We’re losing our snowpack and this is true around the West. More and more of our precipitation is falling as rain instead of snow. When it falls as rain, it just runs off the landscape right away. We don’t get that nice time-release delayed trickle deep into the summer. You start to wonder, if only there was this animal that could build thousands and thousands of reservoirs up in the high country to store some of that water. So that’s a huge one. It’s a lot better than the giant reservoirs on the Colorado or Columbia. 

Beavers support carbon sequestration. Blue carbon is a very hot topic right now and beaver dams and habitat are big stores of blue carbon. They’re fantastic pollution control agents. They’re basically creating these little settling ponds where nitrates, phosphorus, heavy metals and pesticides can settle out, and that’s actually guiding a lot of beaver-based restoration in the Chesapeake Bay watershed which is really impacted by agricultural inputs. 

Another really big one that’s become increasingly exciting as some of the peer-reviewed research has come out to support it is the role of beavers during wildfires. They create these fantastic fire refugia and firebreaks on the landscape, these wet areas where the vegetation is really lush and thus doesn’t burn. This is something that beaver folks had always kind of anecdotally observed, but within the last year or two there has been some great research that proves that point. The notion that you could support safeguarding communities from wildfire by restoring beavers in the surrounding wildlands is suddenly something people are talking about, which is tremendously exciting.

Teo Grossman

TEO: I grew up in Northern New Mexico and my good friend had a house near a beaver dam. We skated on it in winter and we fished and swam in the summer. It was totally dreamy and I’ve always been interested in them as a species, but not in any particularly dramatic or intense way. One of the experiences I had after reading your book was that I underwent this “beaver-believer” experience – I talk about beavers a lot now, possibly to my social detriment. Based on your own pathway that you shared earlier, I’m getting the sense that this is not a unique experience. In the book you dive into the cultural side of the beaver restoration world. Do you have a sense as to what it is that blows people’s minds in such a dramatic way?

BEN: That’s a really good question, and something I’ve often wondered about myself. There are lots of people who love wolves and bears and salmon, but I think the beaver community is one of the larger ones and definitely one of the most passionate ones. I think there are a few reasons for that. For one thing, beavers are just a tremendously empathetic species for us as humans. They’re very relatable. They live in these nuclear family units that really resemble human families in a lot of ways, and they’re relentlessly driven to modify their environment to maximize the provision of food and shelter. They’re really the only other organism that comes anywhere close to us in terms of their drive to change their surroundings. That draws a lot of people to them.

Then they’re just so tremendously interesting behaviorally. You can go to a beaver complex at dusk and just watch them perform the most fascinating, complex behaviors. Why are they building a dam over there and not here? Why do they dig a canal between these two ponds? Why do they put the lodge where it is? All animals have some kind of interesting behavior, but beavers are just so much more complex than most. They’re endlessly fun to interpret. 

There’s so much life at a beaver complex. If you’re going to go birdwatching, and you don’t happen to see the birds that you were looking for, then the day might be a bust. But if you went to a beaver pond and didn’t see the beavers, you would still see great blue herons and woodpeckers and toads and moose. There’s just so much life there that when you visit a beaver compound, you’re visiting an entire ecosystem. I think that’s just incredibly fun and exciting. 

The final thing I’ll say is – and I know this is within the ethos of Bioneers – we are so bombarded by negative, depressing environmental news, and it’s understandable. We’re in a dark place as a global civilization. But the beavers are an amazing ray of light in some ways. They are one of history’s great conservation success stories. The species was basically on the brink of extinction, certainly in the continental United States around the turn of the century, and now there are 15 million of them. They are proof that species can recover. 

Beavers are incredible agents of restoration and positive change on the landscape. They accomplish so much and prove that our efforts to restore nature are not futile, and that positive change really is possible. Beavers are a wonderful, hopeful species at a time when a lot of people need hope.

For more, read an excerpt of EAGER here.

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