Rob Rich

We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us. And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver.

We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us. And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver.

I didn't have like one big light bulb moment. I consider myself very fortunate to, you know, grew up in a family that really supported just my natural curiosities in a lot of ways. And I grew up in the Northeast and spent a lot of time in Northern New York and New England. you know, doing hiking and stuff. And beavers were certainly part of the theme then.

I didn't have like one big light bulb moment. I consider myself very fortunate to, you know, grew up in a family that really supported just my natural curiosities in a lot of ways. And I grew up in the Northeast and spent a lot of time in Northern New York and New England. you know, doing hiking and stuff. And beavers were certainly part of the theme then.

I would spend a lot of time in the woods, saw beavers, but they were just another animal at the time. For me, it wasn't anything like they were changing the world in the way that they do. But I think one of the Kind of milestones for me was going to Isle Royale National Park after college. One of my first wildlife fieldwork gigs was I was helping out with this wolf moose project.

I would spend a lot of time in the woods, saw beavers, but they were just another animal at the time. For me, it wasn't anything like they were changing the world in the way that they do. But I think one of the Kind of milestones for me was going to Isle Royale National Park after college. One of my first wildlife fieldwork gigs was I was helping out with this wolf moose project.

It's called our ostensible purpose was really to track down the bones of moose that were killed by wolves the previous winter. I was there in the summer, and I was just mind-blown with how the beavers had changed the environment there in a way that was not only conducive to the moose, but also really important for supporting the wolves as well.

It's called our ostensible purpose was really to track down the bones of moose that were killed by wolves the previous winter. I was there in the summer, and I was just mind-blown with how the beavers had changed the environment there in a way that was not only conducive to the moose, but also really important for supporting the wolves as well.

One of the leaner times for them is in summer, and so I was just fascinated by this is a time when the wolves have adapted to eat beavers as well. I really got to get... A really close look and just appreciate their keystone role is just how complicated and connected and all the things that they do for diverse animals, predators, prey, and everything in between.

One of the leaner times for them is in summer, and so I was just fascinated by this is a time when the wolves have adapted to eat beavers as well. I really got to get... A really close look and just appreciate their keystone role is just how complicated and connected and all the things that they do for diverse animals, predators, prey, and everything in between.

And so they're a real integrator of a lot of things. And that's one of the areas where it really lit up for me.

And so they're a real integrator of a lot of things. And that's one of the areas where it really lit up for me.

Yeah, thanks. You're welcome. So I think one of the things that is happening is that it is an instinct. There is part of that proclivity to do that instinctually, but it's also a learned response. They've shown how young beavers are actively learning with their parents and watching them and manipulating wood in the same way. And so building a dam is not a necessity for a beaver.

Yeah, thanks. You're welcome. So I think one of the things that is happening is that it is an instinct. There is part of that proclivity to do that instinctually, but it's also a learned response. They've shown how young beavers are actively learning with their parents and watching them and manipulating wood in the same way. And so building a dam is not a necessity for a beaver.

That is not in itself, is not what's necessary.

That is not in itself, is not what's necessary.

Beavers are thriving on lake systems where they can have plenty of water. They're on rivers a lot of times where they can bank up in the side of the riverbank without any consequence. And they don't need to build an entire dam across a river or whatnot to have their way. But what dam building does is it is a mechanism for...

Beavers are thriving on lake systems where they can have plenty of water. They're on rivers a lot of times where they can bank up in the side of the riverbank without any consequence. And they don't need to build an entire dam across a river or whatnot to have their way. But what dam building does is it is a mechanism for...

extending their safety from predators, but also increasing their access to food. And so when they build a dam in a stream system, it's not only spreading the water out across the stream system laterally, but it's also stacking up a lot of weight behind that dam. And so it's sinking more water into exchange with the groundwater system.

extending their safety from predators, but also increasing their access to food. And so when they build a dam in a stream system, it's not only spreading the water out across the stream system laterally, but it's also stacking up a lot of weight behind that dam. And so it's sinking more water into exchange with the groundwater system.

And I think too often we just think of our river systems as one upstream, downstream, going one way. And what's natural about rivers and watershed systems is that when they spread out as well as down, so laterally and vertically as well. And the researcher Ellen Wohl has just done a lot of great work showing that kind of hydrological complexity of beaver systems.

And I think too often we just think of our river systems as one upstream, downstream, going one way. And what's natural about rivers and watershed systems is that when they spread out as well as down, so laterally and vertically as well. And the researcher Ellen Wohl has just done a lot of great work showing that kind of hydrological complexity of beaver systems.

But when the water spreads out, you know, they are very comfortable in water. but not as much on land. You've got to imagine a beaver has front feet that are very dexterous, about the size of a deck of cards or so. And then the hind feet are double or even more than double that size. And they're webbed, entirely webbed.

But when the water spreads out, you know, they are very comfortable in water. but not as much on land. You've got to imagine a beaver has front feet that are very dexterous, about the size of a deck of cards or so. And then the hind feet are double or even more than double that size. And they're webbed, entirely webbed.

So it's like walking on hands on one part, but then enormous flippers on the back. And so they're very awkward and just very slow. And they do smell a lot. And so they're very attractive to a number of predators on land. And so being in water is a safe place for them. They're just ultimate graceful in the water. And so that's safe.

So it's like walking on hands on one part, but then enormous flippers on the back. And so they're very awkward and just very slow. And they do smell a lot. And so they're very attractive to a number of predators on land. And so being in water is a safe place for them. They're just ultimate graceful in the water. And so that's safe.

And as the water extends, they're both encouraging new like willow, aspen, cottonwood regeneration, and then able to access that for their own food and building uses as well.

And as the water extends, they're both encouraging new like willow, aspen, cottonwood regeneration, and then able to access that for their own food and building uses as well.

Yeah, that's right. A lot of species, wherever beavers were in that range, have co-evolved with beavers and depend on their work and their disturbance factor to make the habitats where they thrive. And so willows are just a consummate example of that. They're

Yeah, that's right. A lot of species, wherever beavers were in that range, have co-evolved with beavers and depend on their work and their disturbance factor to make the habitats where they thrive. And so willows are just a consummate example of that. They're

truly an amazing plant in their ability to be you know just a sprig if it's attached you know gets a little bit of a root hold in moist soil can just take off and can propagate very fast in ways that are really great and so Beavers are a little bit different than like an elk or a deer or other browser in that they're not seeking so much the buds. They don't want that just fresh shoot growth.

truly an amazing plant in their ability to be you know just a sprig if it's attached you know gets a little bit of a root hold in moist soil can just take off and can propagate very fast in ways that are really great and so Beavers are a little bit different than like an elk or a deer or other browser in that they're not seeking so much the buds. They don't want that just fresh shoot growth.

And so plants like willows, aspens, cottonwoods, those are kind of their... three favorites, really. Those are some of the plants that evolved in those riparian systems that really thrive as well. And so it is a very dynamic cycle. And beavers, they create diversity by being dynamic. One of the things that they do is they don't always stay in that spot.

And so plants like willows, aspens, cottonwoods, those are kind of their... three favorites, really. Those are some of the plants that evolved in those riparian systems that really thrive as well. And so it is a very dynamic cycle. And beavers, they create diversity by being dynamic. One of the things that they do is they don't always stay in that spot.

As one food patch will become diminished a little bit, they'll shift to another. And so at each of those different stages, temporally in the beaver succession, that brings a whole new suite of species that will thrive in that altered state. And so it's a constantly shifting mosaic that beavers really promote.

As one food patch will become diminished a little bit, they'll shift to another. And so at each of those different stages, temporally in the beaver succession, that brings a whole new suite of species that will thrive in that altered state. And so it's a constantly shifting mosaic that beavers really promote.

Yes. I mean, one of the greatest predictors of future beaver habitat is historic beaver presence. And so that's why it's important to have that eye to be able to see where a prior dam complex was or other old chew sign that you can see on sticks and things around. Those are all great signs. for where future beavers could establish as well.

Yes. I mean, one of the greatest predictors of future beaver habitat is historic beaver presence. And so that's why it's important to have that eye to be able to see where a prior dam complex was or other old chew sign that you can see on sticks and things around. Those are all great signs. for where future beavers could establish as well.

And that's really important for people involved in beaver restoration is looking at kind of where those prior sites were productive because those are the places that they will likely come back to.

And that's really important for people involved in beaver restoration is looking at kind of where those prior sites were productive because those are the places that they will likely come back to.

Yeah, great question. So it does vary a ton, but generally they are working very hard and in a way very fast on it. Sometimes alterations or blowouts will happen in a dam system naturally or human caused for various reasons. And beavers are very fast to return to that leak and triggered a lot by the sound of flowing water as well. The instinct, that is a trigger to where the leak is, so to speak.

Yeah, great question. So it does vary a ton, but generally they are working very hard and in a way very fast on it. Sometimes alterations or blowouts will happen in a dam system naturally or human caused for various reasons. And beavers are very fast to return to that leak and triggered a lot by the sound of flowing water as well. The instinct, that is a trigger to where the leak is, so to speak.

But I also sometimes resist the idea of just the busy being a beaver. If you ever get the chance to watch a beaver doing its work in this setting, they're never frenzied in their activity. I always really appreciate just how deliberate and just like tactful they are in placement. It's more of just like a constant process as opposed to just like this frenzy of activity. And

But I also sometimes resist the idea of just the busy being a beaver. If you ever get the chance to watch a beaver doing its work in this setting, they're never frenzied in their activity. I always really appreciate just how deliberate and just like tactful they are in placement. It's more of just like a constant process as opposed to just like this frenzy of activity. And

They have just really mastered the art of maintenance. I think so many of us humans just don't know how to do basic maintenance activities sometimes. We can dispose of something or get a new one, but we don't know how to really just tinker and maintain things over time.

They have just really mastered the art of maintenance. I think so many of us humans just don't know how to do basic maintenance activities sometimes. We can dispose of something or get a new one, but we don't know how to really just tinker and maintain things over time.

And so I think that's part of what makes beaver structures so resilient is that they're constantly evolving and adapting with the changes that they're facing.

And so I think that's part of what makes beaver structures so resilient is that they're constantly evolving and adapting with the changes that they're facing.

Kind of all of the above. It generally starts with, you know, just some berming of some mud at the base. You know, it's not only stick. So there's some anchoring things in there going on, like the mud. Sometimes even rocks are rolled in and stones can be rolled in as part of like a supporting base. But, you know, it's it is a very complex. And remember, this is in a aquatic environment.

Kind of all of the above. It generally starts with, you know, just some berming of some mud at the base. You know, it's not only stick. So there's some anchoring things in there going on, like the mud. Sometimes even rocks are rolled in and stones can be rolled in as part of like a supporting base. But, you know, it's it is a very complex. And remember, this is in a aquatic environment.

environment where water is flowing around all the time, you don't have the, you know, the ability to do this in dry times, but they use that to their advantage as well. And then as it crests out of the water, you know, they do add a berm of mud, especially on that upstream edge where the water is pounding.

environment where water is flowing around all the time, you don't have the, you know, the ability to do this in dry times, but they use that to their advantage as well. And then as it crests out of the water, you know, they do add a berm of mud, especially on that upstream edge where the water is pounding.

And they will use mud as well to kind of add a little shellac like coating to it to keep it from just water getting through all those crannies of the sticks, so to speak.

And they will use mud as well to kind of add a little shellac like coating to it to keep it from just water getting through all those crannies of the sticks, so to speak.

Yeah, very much all the above. I think it's not a gendered activity. I think both male and female contribute to dam building and the yearlings as well. It takes the kits a little bit of time to get comfortable to that point. When they're born, they actually don't have their waterproofing gland active yet. And so they stay in the lodge for a little bit of a time.

Yeah, very much all the above. I think it's not a gendered activity. I think both male and female contribute to dam building and the yearlings as well. It takes the kits a little bit of time to get comfortable to that point. When they're born, they actually don't have their waterproofing gland active yet. And so they stay in the lodge for a little bit of a time.

But after they get that waterproofing gland active and they can be in the water effectively, you know, they will also watch and participate and learn from the process as well.

But after they get that waterproofing gland active and they can be in the water effectively, you know, they will also watch and participate and learn from the process as well.

I believe so. I'm not as familiar with those type of environments, but play and just experimenting and using those tools is very important for

I believe so. I'm not as familiar with those type of environments, but play and just experimenting and using those tools is very important for

So many animals, you look at bears or wolves or any other animals that are socially oriented like that, that watch each other, learn from each other, and do have play, that play and practicing with their future tools kind of as a very important instinct or way of entering their future work. And so I think that is a possibility, yeah.

So many animals, you look at bears or wolves or any other animals that are socially oriented like that, that watch each other, learn from each other, and do have play, that play and practicing with their future tools kind of as a very important instinct or way of entering their future work. And so I think that is a possibility, yeah.

Rob Rich, he, him is great.

Rob Rich, he, him is great.

So definitely not hairy. It is more scaly. So the beaver tail is really a fascinating part of their body in a lot of ways.

So definitely not hairy. It is more scaly. So the beaver tail is really a fascinating part of their body in a lot of ways.

Generally not castorologists. There was an early book in the late 1800s that had that name actually, but Generally, it's not castorology. It's either just beaver fans, beaver believers, all the things that are associated with interest and curiosity about beavers.

Generally not castorologists. There was an early book in the late 1800s that had that name actually, but Generally, it's not castorology. It's either just beaver fans, beaver believers, all the things that are associated with interest and curiosity about beavers.

For one, it's used a little bit as a rudder as they're swimming through the water. And so it can help them steer a little bit. It's also important when they're propping up to chew down a tree or whatnot. And one of the most important functions of it, though, It's a very important alarm system as well.

For one, it's used a little bit as a rudder as they're swimming through the water. And so it can help them steer a little bit. It's also important when they're propping up to chew down a tree or whatnot. And one of the most important functions of it, though, It's a very important alarm system as well.

You've probably either heard yourself or heard of beavers slapping their tail as they get alarmed by predator or potential threat or some other non-related beaver or some other concern in their environment. They will really have this impressive slap.

You've probably either heard yourself or heard of beavers slapping their tail as they get alarmed by predator or potential threat or some other non-related beaver or some other concern in their environment. They will really have this impressive slap.

action on the water, and it is kind of jolting, and that is a warning to other beavers that there might be a threat around, and so they know how to respond to that. But the fourth one that's so important that the tail does is that it's very much a heat or a thermoregulation and heat storage, energy storage organ.

action on the water, and it is kind of jolting, and that is a warning to other beavers that there might be a threat around, and so they know how to respond to that. But the fourth one that's so important that the tail does is that it's very much a heat or a thermoregulation and heat storage, energy storage organ.

In the winter, that is the part of their body that becomes quite larger than it is in the summer. They have a lot of body fat, but they take on most of that in the winter and store it in their tail.

In the winter, that is the part of their body that becomes quite larger than it is in the summer. They have a lot of body fat, but they take on most of that in the winter and store it in their tail.

And so that is really important for one of the ways for them to keep warm in the winter. So the outside is very scaly, always black. And that has also been shown to have a unique signature. You can look at the tail. and tell individual beavers by their tail details, just like we can with a fingerprint on a human.

And so that is really important for one of the ways for them to keep warm in the winter. So the outside is very scaly, always black. And that has also been shown to have a unique signature. You can look at the tail. and tell individual beavers by their tail details, just like we can with a fingerprint on a human.

But then inside of the tail, it's just very thickly layered of white gelatinous kind of fat. And so all that fat is what's really important to further heat storage in the winter.

But then inside of the tail, it's just very thickly layered of white gelatinous kind of fat. And so all that fat is what's really important to further heat storage in the winter.

There is a central node of vertebra extending down through the tail that is in the center of it there, but it's more filled with more capillary like blood vessels. And so there's very lot of blood exchange in there that keeps it from freezing in those times. And again, serving that heat storage purpose. So other than that central area of bone going down the middle, it is entirely fat pretty much.

There is a central node of vertebra extending down through the tail that is in the center of it there, but it's more filled with more capillary like blood vessels. And so there's very lot of blood exchange in there that keeps it from freezing in those times. And again, serving that heat storage purpose. So other than that central area of bone going down the middle, it is entirely fat pretty much.

Sure.

Sure.

That's kind of the classic at the moment.

That's kind of the classic at the moment.

Their teeth are supported by a skull that makes their teeth effective. And so they have a very flat-topped, wide skull with these things we call zygomatic arches, which are what we call cheekbones sometimes.

Their teeth are supported by a skull that makes their teeth effective. And so they have a very flat-topped, wide skull with these things we call zygomatic arches, which are what we call cheekbones sometimes.

And so when those are so wide spreading, that allows for a lot of muscle attachment coming down over the top of their cranium, attaching to the outside of those cheekbones, and then going down into their mandible. And so... All that complex muscle attachment does make for a lot of jaw strength.

And so when those are so wide spreading, that allows for a lot of muscle attachment coming down over the top of their cranium, attaching to the outside of those cheekbones, and then going down into their mandible. And so... All that complex muscle attachment does make for a lot of jaw strength.

I can guarantee you it's quite strong to bring down to cottonwood or a large tree that is double the size of their body or something.

I can guarantee you it's quite strong to bring down to cottonwood or a large tree that is double the size of their body or something.

Yeah, I'm calling from northwest Montana, and I live in a valley called the Swan Valley, a little bit northeast of Missoula and south of Kalispell, up against a part of the Rocky Mountains there and below Glacier National Park. This is a special valley in a lot of ways. It's very well watered.

Yeah, I'm calling from northwest Montana, and I live in a valley called the Swan Valley, a little bit northeast of Missoula and south of Kalispell, up against a part of the Rocky Mountains there and below Glacier National Park. This is a special valley in a lot of ways. It's very well watered.

But the teeth themselves, like all rodents, they're defined by, you know, ever-growing incisors. And so those are kind of the hallmark front teeth that we see. And then they've got a really robust set of molars as well. And so... The molars are for grinding, masticating all that wood pulp down is important. But the incisors are what do the heavy work of the cutting.

But the teeth themselves, like all rodents, they're defined by, you know, ever-growing incisors. And so those are kind of the hallmark front teeth that we see. And then they've got a really robust set of molars as well. And so... The molars are for grinding, masticating all that wood pulp down is important. But the incisors are what do the heavy work of the cutting.

And so on the top ones, they're very orange on the outside. And so if you see a beaver's front teeth, you will see that orange that's enamel. And it's colored that way because of some of the iron and the compounds that they eat in the wood that they're having. But that closes over a wider area on the bottom teeth that is called dentine. And so that wider area is softer. The enamel is harder.

And so on the top ones, they're very orange on the outside. And so if you see a beaver's front teeth, you will see that orange that's enamel. And it's colored that way because of some of the iron and the compounds that they eat in the wood that they're having. But that closes over a wider area on the bottom teeth that is called dentine. And so that wider area is softer. The enamel is harder.

When they rub against each other like that, it's a constantly sharpening chisel. And so the beaver's teeth are extremely sharp and constantly becoming more so. And if they don't have access to wood and don't keep gnawing and working on that, then The teeth will keep growing and can become quite a dental hazard for them. So they do require wood for that purpose as well.

When they rub against each other like that, it's a constantly sharpening chisel. And so the beaver's teeth are extremely sharp and constantly becoming more so. And if they don't have access to wood and don't keep gnawing and working on that, then The teeth will keep growing and can become quite a dental hazard for them. So they do require wood for that purpose as well.

But yeah, hard enamel outside, soft white kind of dentine on the inside for those incisors, and then just a lot of continuous action to keep it sharp.

But yeah, hard enamel outside, soft white kind of dentine on the inside for those incisors, and then just a lot of continuous action to keep it sharp.

It has a lot of historic beaver activity and current and was also shaped by glaciers, which the beavers actively followed.

It has a lot of historic beaver activity and current and was also shaped by glaciers, which the beavers actively followed.

Great. So they are definitely 100% vegan. No animal fare of note in maybe an insect or something will slip in occasionally, but there's very minimal to no record of of them relying on any animal food in their diet.

Great. So they are definitely 100% vegan. No animal fare of note in maybe an insect or something will slip in occasionally, but there's very minimal to no record of of them relying on any animal food in their diet.

And so in the spring and summer and warmer months when the veg is succulent and there's a lot of herbaceous or non-woody plants out there, there's a number of wetland-associated plants that they will eat. They will also use the roots of certain things, like water lily roots are sometimes important for beavers.

And so in the spring and summer and warmer months when the veg is succulent and there's a lot of herbaceous or non-woody plants out there, there's a number of wetland-associated plants that they will eat. They will also use the roots of certain things, like water lily roots are sometimes important for beavers.

And just in the water lily pad leaves, a lot of those succulent plants are not available, certainly year-round. When they cut down a tree or cut down a branch or whatnot, they're not ingesting the entire thing. They're mostly after what we call the cambium, which is this thin layer of sugary cells where the tree is actively growing. And so most of what we call on a tree is actually dead cambium.

And just in the water lily pad leaves, a lot of those succulent plants are not available, certainly year-round. When they cut down a tree or cut down a branch or whatnot, they're not ingesting the entire thing. They're mostly after what we call the cambium, which is this thin layer of sugary cells where the tree is actively growing. And so most of what we call on a tree is actually dead cambium.

cellulose material. It's not something that is nutritious in any way, but they will seek out that cambium layer just below the bark and below before you get into the real kind of deadwood of the tree. And so they will eat first and then use some for building or some they're just used for feeding as well. A little bit of a mixed bag there.

cellulose material. It's not something that is nutritious in any way, but they will seek out that cambium layer just below the bark and below before you get into the real kind of deadwood of the tree. And so they will eat first and then use some for building or some they're just used for feeding as well. A little bit of a mixed bag there.

It's about a golf ball-sized lump a lot of times. And I sometimes liken it to shredded wheat or something. It takes that kind of character. And beetrovers are one of the rodents, in addition to the lagomorphs, the rabbits and pikas and whatnot, that will re-ingest their own first poop. And so they will eat that to kind of extract a second round of nutrients out of it.

It's about a golf ball-sized lump a lot of times. And I sometimes liken it to shredded wheat or something. It takes that kind of character. And beetrovers are one of the rodents, in addition to the lagomorphs, the rabbits and pikas and whatnot, that will re-ingest their own first poop. And so they will eat that to kind of extract a second round of nutrients out of it.

This is a practice called coprophagy. Delicious. And so by the time it comes out that second time, it is very loose, easily disintegrated lump of sawdust like shredded wheat. Most of the time it's deposited in water. And so it's very prone to disintegration quite quickly.

This is a practice called coprophagy. Delicious. And so by the time it comes out that second time, it is very loose, easily disintegrated lump of sawdust like shredded wheat. Most of the time it's deposited in water. And so it's very prone to disintegration quite quickly.

In a way, yeah. The last glaciation that covered America was about 10,000 to 12,000 years ago, I believe, as it pocked out a lot of depressional wetlands and carved the rivers in certain ways that made it really conducive to complex flows, which beavers are actively seeking out all the time. And so they find in glaciated regions of North America.

In a way, yeah. The last glaciation that covered America was about 10,000 to 12,000 years ago, I believe, as it pocked out a lot of depressional wetlands and carved the rivers in certain ways that made it really conducive to complex flows, which beavers are actively seeking out all the time. And so they find in glaciated regions of North America.

Great. So the two marks are definitely something you want to look for. And if you don't see them and you know there are beavers there, you want to be looking for a cut on the branch at a 45 degree angle. That's just because of how they kind of turn their head and then how the branch typically falls. It's kind of like this...

Great. So the two marks are definitely something you want to look for. And if you don't see them and you know there are beavers there, you want to be looking for a cut on the branch at a 45 degree angle. That's just because of how they kind of turn their head and then how the branch typically falls. It's kind of like this...

angled cut, which is typical of all rodents really, but that sharp angled cut is really important. To see beavers, they are, you know, fascinating because they're at once very conspicuous.

angled cut, which is typical of all rodents really, but that sharp angled cut is really important. To see beavers, they are, you know, fascinating because they're at once very conspicuous.

You can see their activity from aerial images, which is fascinating, but they're also kind of cryptic sometimes in that they do prefer to be active at nocturnal or crepuscular kind of dawn dusk kind of times sometimes. So a great time is really to just get out there first thing in the morning,

You can see their activity from aerial images, which is fascinating, but they're also kind of cryptic sometimes in that they do prefer to be active at nocturnal or crepuscular kind of dawn dusk kind of times sometimes. So a great time is really to just get out there first thing in the morning,

And you can kind of wake up with them as they're about to tuck in for their time kind of in the lodge or their safe spot for the day. And they'll typically come out in the more dusk hours as well. Those are kind of good times to try. But beavers are not hard and fast about being nocturnal. You can find them during the day as well. Yeah.

And you can kind of wake up with them as they're about to tuck in for their time kind of in the lodge or their safe spot for the day. And they'll typically come out in the more dusk hours as well. Those are kind of good times to try. But beavers are not hard and fast about being nocturnal. You can find them during the day as well. Yeah.

Yeah, great question. So again, a lodge, you are correct, the lodge is separate from a dam. And so they're not ever living in the dam, but they are definitely using a variety of different lodge styles. And sometimes they can be like freestanding in the water. And sometimes they can be half affixed to like a bank. Sometimes it can just be a hole dug into a bank and they burrowed in that way. But

Yeah, great question. So again, a lodge, you are correct, the lodge is separate from a dam. And so they're not ever living in the dam, but they are definitely using a variety of different lodge styles. And sometimes they can be like freestanding in the water. And sometimes they can be half affixed to like a bank. Sometimes it can just be a hole dug into a bank and they burrowed in that way. But

Those are the places where they're living and kind of sheltering over winter if it's in an environment where they need to do that. And they are not impenetrable, but they are very difficult to enter for a lot of predators. The ones that are made of sticks and mud are generally like the dam in a way. The sticks are kind of latticed in and then the mud fills in a lot of the cracks.

Those are the places where they're living and kind of sheltering over winter if it's in an environment where they need to do that. And they are not impenetrable, but they are very difficult to enter for a lot of predators. The ones that are made of sticks and mud are generally like the dam in a way. The sticks are kind of latticed in and then the mud fills in a lot of the cracks.

And so when that freezes in the winter, that can become pretty rock hard. And they do all... All the family is living in there together. One of my most fascinating parts of beaver existence is just that time in the winter of how they're doing that under the ice, in the darkness, in cold environments, in wet environments.

And so when that freezes in the winter, that can become pretty rock hard. And they do all... All the family is living in there together. One of my most fascinating parts of beaver existence is just that time in the winter of how they're doing that under the ice, in the darkness, in cold environments, in wet environments.

And so beavers and glaciers together are two of the major continental shapers of North America.

And so beavers and glaciers together are two of the major continental shapers of North America.

And it's just, you know, we thought COVID was bad and isolation in a lot of ways. I mean, they are very much isolated in that time when they can't come back out above water surface for months at a time, potentially. It does have... different layers, terraces, a lot of times you can see in them.

And it's just, you know, we thought COVID was bad and isolation in a lot of ways. I mean, they are very much isolated in that time when they can't come back out above water surface for months at a time, potentially. It does have... different layers, terraces, a lot of times you can see in them.

If you ever are lucky enough to find a abandoned beaver lodge, sometimes I have been able to enter into some of the chutes that go into a lodge and you can see for yourself kind of what the size is like, but it can generally fit them together, generally some body warmth in there involved.

If you ever are lucky enough to find a abandoned beaver lodge, sometimes I have been able to enter into some of the chutes that go into a lodge and you can see for yourself kind of what the size is like, but it can generally fit them together, generally some body warmth in there involved.

But Casey McFarland, who's a great tracker and wildlife ecologist, he has a great video just showing one of those abandoned beaver lodges, what the interior is like.

But Casey McFarland, who's a great tracker and wildlife ecologist, he has a great video just showing one of those abandoned beaver lodges, what the interior is like.

But in the lodges, there can be muskrats, particularly one that are often cohabitating with beavers. And there are things like spiders, all sorts of invertebrates and insects that are certainly dwelling in there, sometimes amphibians as well. And then after the beavers leave sometimes, there can be other larger animals that use them as well.

But in the lodges, there can be muskrats, particularly one that are often cohabitating with beavers. And there are things like spiders, all sorts of invertebrates and insects that are certainly dwelling in there, sometimes amphibians as well. And then after the beavers leave sometimes, there can be other larger animals that use them as well.

Sage Raymond is a colleague that has done really neat work up in Elk Island National Park in Alberta, just showing that coyotes and porcupines and different animals are following after the beaver to use those where tree sources are limited. And so beavers are incredibly important throughout, again, throughout their temporal history of their wetland complexes is fascinating to me.

Sage Raymond is a colleague that has done really neat work up in Elk Island National Park in Alberta, just showing that coyotes and porcupines and different animals are following after the beaver to use those where tree sources are limited. And so beavers are incredibly important throughout, again, throughout their temporal history of their wetland complexes is fascinating to me.

Yes. To survive in the winter, most of the times they're relying on what we call a cache. And so it's like this stored up mass of sticks that they will plug into the floor of the stream or pond or whatever water source they're on. And this is just this raft of sticks that they have piled up and are in the bottom of the water source there. And so that is their primary food during the winter.

Yes. To survive in the winter, most of the times they're relying on what we call a cache. And so it's like this stored up mass of sticks that they will plug into the floor of the stream or pond or whatever water source they're on. And this is just this raft of sticks that they have piled up and are in the bottom of the water source there. And so that is their primary food during the winter.

Yeah, so that's a great question. You know, the beaver evolution is very complex. And we actually at one time had 33 different genera of beavers and genera like the genus species binomial classification. So we had 33 different types of genus of beaver across the northern hemisphere at one time. And that is totally, at this point, winnowed down to one genus, the genus Castor.

Yeah, so that's a great question. You know, the beaver evolution is very complex. And we actually at one time had 33 different genera of beavers and genera like the genus species binomial classification. So we had 33 different types of genus of beaver across the northern hemisphere at one time. And that is totally, at this point, winnowed down to one genus, the genus Castor.

And they're going in and out of the lodge to access that. There is a certain time before freeze up where it's not quite frozen, but it's not quite flowing water everywhere either. So it's kind of that delicate in-between time. And they will use their flat, thick, scald head to kind of bash up through thinner ice to do that and keep it open as long as they can.

And they're going in and out of the lodge to access that. There is a certain time before freeze up where it's not quite frozen, but it's not quite flowing water everywhere either. So it's kind of that delicate in-between time. And they will use their flat, thick, scald head to kind of bash up through thinner ice to do that and keep it open as long as they can.

But in my area, there does come a point where there is no more of that bashing to be had. And the ice just takes over. And so once that happens, they are fully locked under there for months at a time.

But in my area, there does come a point where there is no more of that bashing to be had. And the ice just takes over. And so once that happens, they are fully locked under there for months at a time.

You can tell activity sometimes. One of the fascinating signs to look for is these bubble trails that go in and out. of air escaping from their interstitial spaces of their fur. There's air trapped in there. And so when they go in and out of their lodge, all those bubbles are escaping from their fur and rising up to the surface of the ice.

You can tell activity sometimes. One of the fascinating signs to look for is these bubble trails that go in and out. of air escaping from their interstitial spaces of their fur. There's air trapped in there. And so when they go in and out of their lodge, all those bubbles are escaping from their fur and rising up to the surface of the ice.

And so before the ice gets all snowed over and kind of opaque, you can see those bubbles to see where the beavers have been coming and going. But after that, after the snow gets all over the ice, it is pretty much total darkness for potentially a month at a time.

And so before the ice gets all snowed over and kind of opaque, you can see those bubbles to see where the beavers have been coming and going. But after that, after the snow gets all over the ice, it is pretty much total darkness for potentially a month at a time.

So it is multi-layered as well. It's super dense. It's one of the most dense furs of animals on the planet, really, right up there with sea otter and other semi-aquatic mammals that are spending a lot of time in really cold water in really cold northerly environments. And so it is dense. The layer on the outside that you would touch first is coarser. It's composed of more guard hairs.

So it is multi-layered as well. It's super dense. It's one of the most dense furs of animals on the planet, really, right up there with sea otter and other semi-aquatic mammals that are spending a lot of time in really cold water in really cold northerly environments. And so it is dense. The layer on the outside that you would touch first is coarser. It's composed of more guard hairs.

That's what waterproofing oils from their anal glands are constantly being lathered onto to keep them as sleek and waterproof as possible. But below that, you get more into some more downy, dense layers that are even softer. And so that is what's kind of right up against their body. The fur is so dense. I've heard it. One stat I seem to recall is like 23,000 hairs per square centimeter.

That's what waterproofing oils from their anal glands are constantly being lathered onto to keep them as sleek and waterproof as possible. But below that, you get more into some more downy, dense layers that are even softer. And so that is what's kind of right up against their body. The fur is so dense. I've heard it. One stat I seem to recall is like 23,000 hairs per square centimeter.

And so you can imagine a square centimeter. That is not large, but that is a ton of hairs in that area.

And so you can imagine a square centimeter. That is not large, but that is a ton of hairs in that area.

And Castor canadensis is the North American beaver, the only one native to this continent. And Castor fiber is the beaver, the Eurasian beaver, and that is over in Europe and parts of Northern Asia as well.

And Castor canadensis is the North American beaver, the only one native to this continent. And Castor fiber is the beaver, the Eurasian beaver, and that is over in Europe and parts of Northern Asia as well.

And so that density is probably about 25% of the beaver's insulation through the winter. And so even all that hair, because they're in the water so much, doesn't do all their needs to stay insulated. And that's why they rely so much on their fat stores as well to accommodate the rest of their insulation. But it is incredibly dense fur and it is in the interior very soft. Yeah.

And so that density is probably about 25% of the beaver's insulation through the winter. And so even all that hair, because they're in the water so much, doesn't do all their needs to stay insulated. And that's why they rely so much on their fat stores as well to accommodate the rest of their insulation. But it is incredibly dense fur and it is in the interior very soft. Yeah.

So that varies. The tail, I think, was definitely relied on at certain times in certain people that live in climates where that was needed throughout human evolution. They have certainly relied on beaver tail as a fat source. And beaver meat as well is something that has a lot of importance in certain times of human evolution.

So that varies. The tail, I think, was definitely relied on at certain times in certain people that live in climates where that was needed throughout human evolution. They have certainly relied on beaver tail as a fat source. And beaver meat as well is something that has a lot of importance in certain times of human evolution.

About 33 million years ago, I believe, is when the beavers really started diversifying. And a lot of rodents generally, that was a really time of... rodent diversification. And so we had beavers, one that was kind of more recent times, the castoroides that lived just south of the glacial ice sheets and whatnot.

About 33 million years ago, I believe, is when the beavers really started diversifying. And a lot of rodents generally, that was a really time of... rodent diversification. And so we had beavers, one that was kind of more recent times, the castoroides that lived just south of the glacial ice sheets and whatnot.

I can't really speak to what the first listener was talking about, about wrecking the world. I think that would be a little bit extreme. Beavers, like I said, wanted to start here that for seven and a half million odd years, they've been on this continent shaping and transforming it in different ways. And We, at one point, had between 100 and 400 million beavers across North America.

I can't really speak to what the first listener was talking about, about wrecking the world. I think that would be a little bit extreme. Beavers, like I said, wanted to start here that for seven and a half million odd years, they've been on this continent shaping and transforming it in different ways. And We, at one point, had between 100 and 400 million beavers across North America.

And in the course of about three centuries, in about the 1600s through the early 1900s, that winnowed down to about 100,000 beavers.

And in the course of about three centuries, in about the 1600s through the early 1900s, that winnowed down to about 100,000 beavers.

And so we are very lucky that they didn't become extinct or endangered. But their populations at this point are very patchy, dispersed, and in many places recovering. But beavers do not need us to keep them kind of their populations in control. I mean, they for all those years, they have had

And so we are very lucky that they didn't become extinct or endangered. But their populations at this point are very patchy, dispersed, and in many places recovering. But beavers do not need us to keep them kind of their populations in control. I mean, they for all those years, they have had

And so that was one that was about the size of a bear, almost like 175, 200 pounds in a very large beaver. We had beavers, one called paleocastor that actually dug corkscrew-like tunnels with its teeth into what we now know as the prairies of Nebraska. And so very different lifestyle.

And so that was one that was about the size of a bear, almost like 175, 200 pounds in a very large beaver. We had beavers, one called paleocastor that actually dug corkscrew-like tunnels with its teeth into what we now know as the prairies of Nebraska. And so very different lifestyle.

Other predators that are doing that effectively and their own population saturation densities is an important regulation on that. And so I think a lot of times where the conflicts come into play is that we are...

Other predators that are doing that effectively and their own population saturation densities is an important regulation on that. And so I think a lot of times where the conflicts come into play is that we are...

living in the same places that beavers also thrive in in other words those low-lying arable flood plains and good soil and all those things where there's good water access and things those are the things people want too and so there's a lot of times some tension there but uh there's a lot of other non-lethal solutions to beaver coexistence as well.

living in the same places that beavers also thrive in in other words those low-lying arable flood plains and good soil and all those things where there's good water access and things those are the things people want too and so there's a lot of times some tension there but uh there's a lot of other non-lethal solutions to beaver coexistence as well.

And so a lot of times when that's used as a solution to beaver problems, that's really just creating a void for new beavers to come in. Because again, if the habitat is good, future beavers will find that and be a part of that somehow.

And so a lot of times when that's used as a solution to beaver problems, that's really just creating a void for new beavers to come in. Because again, if the habitat is good, future beavers will find that and be a part of that somehow.

No, you're right. Not as prolific as other rodents, for sure. And only one litter per year. And they generally are mating in late winter, January, February, and then having their kits in May, June, around that time. So yeah, mice and voles and other rodents that are much more prolific than beavers are. So they're not that prolific, really.

No, you're right. Not as prolific as other rodents, for sure. And only one litter per year. And they generally are mating in late winter, January, February, and then having their kits in May, June, around that time. So yeah, mice and voles and other rodents that are much more prolific than beavers are. So they're not that prolific, really.

Wow, great question and great observation. I think I do not have the answer to that, but I do know that beavers do play and I do know that there are interspecies interactions, intraspecies interactions that we are constantly learning about. And that's one of the areas that I'm most fascinated by is the beavers themselves, but also how they're shaping and interacting with

Wow, great question and great observation. I think I do not have the answer to that, but I do know that beavers do play and I do know that there are interspecies interactions, intraspecies interactions that we are constantly learning about. And that's one of the areas that I'm most fascinated by is the beavers themselves, but also how they're shaping and interacting with

all kinds of species from the butterflies that are attracted to the sap on the branches they cut to other things they're swimming around. And so I can't say it's a regular thing that beavers and ducks are playing together, but I would not doubt that there's possibility for interaction there that I've not observed either.

all kinds of species from the butterflies that are attracted to the sap on the branches they cut to other things they're swimming around. And so I can't say it's a regular thing that beavers and ducks are playing together, but I would not doubt that there's possibility for interaction there that I've not observed either.

For sure. Yeah, they're really central to the work I do and I'm a part of tangentially and directly. The Beaver Deceiver is kind of pioneered and patented by this guy named Skip Lyle, really brilliant guy based out of Vermont currently.

For sure. Yeah, they're really central to the work I do and I'm a part of tangentially and directly. The Beaver Deceiver is kind of pioneered and patented by this guy named Skip Lyle, really brilliant guy based out of Vermont currently.

But he grew up around just watching trapping take place and whatnot and was like, sure, there had to be a better way than just this remove and fill the void, just this never-ending cycle. that all kinds of road crews and private landowners and public agencies are dealing with.

But he grew up around just watching trapping take place and whatnot and was like, sure, there had to be a better way than just this remove and fill the void, just this never-ending cycle. that all kinds of road crews and private landowners and public agencies are dealing with.

Sometimes culverts, you know, those big pipes that go under a road to allow the stream through, you know, to a beaver, that is just like a ready-made dam with a hole in it. And so beavers are always plugging these culverts with their sticks and mud and whatnot and causing a real headache for a lot of those people.

Sometimes culverts, you know, those big pipes that go under a road to allow the stream through, you know, to a beaver, that is just like a ready-made dam with a hole in it. And so beavers are always plugging these culverts with their sticks and mud and whatnot and causing a real headache for a lot of those people.

But it wasn't until they really converged on that semi-aquatic behavior and the wood cutting and dam building behaviors. When all three of those parts converged in the Beaver, that is what drew their evolutionary success. And that's kind of the one that's persisting today.

But it wasn't until they really converged on that semi-aquatic behavior and the wood cutting and dam building behaviors. When all three of those parts converged in the Beaver, that is what drew their evolutionary success. And that's kind of the one that's persisting today.

And so the beaver deceiver is one way to exclude them from these high conflict areas like culverts. In its simplest definition, it's kind of like a fence that goes around the culvert to exclude that, but you want to do it at the right angle and the right distance and the right site-specific ways that it's effective. And so... Skip Lyle kind of pioneered that.

And so the beaver deceiver is one way to exclude them from these high conflict areas like culverts. In its simplest definition, it's kind of like a fence that goes around the culvert to exclude that, but you want to do it at the right angle and the right distance and the right site-specific ways that it's effective. And so... Skip Lyle kind of pioneered that.

But then there's also some like flow device things that are kind of like a pipe that we put through a dam that can siphon water through a dam from upstream to downstream. And so that allows people to kind of strike a compromise with the beaver in the sense that they can still stay there, they can still have their dam and still have all the benefits to their ecology there.

But then there's also some like flow device things that are kind of like a pipe that we put through a dam that can siphon water through a dam from upstream to downstream. And so that allows people to kind of strike a compromise with the beaver in the sense that they can still stay there, they can still have their dam and still have all the benefits to their ecology there.

But the water level can be lowered just enough where it's not as much of a headache for other people that are worried about getting flooded out or that type of thing. And there are numerous entities growing up all around the country right now that are starting these. California is one of the biggest success stories right now.

But the water level can be lowered just enough where it's not as much of a headache for other people that are worried about getting flooded out or that type of thing. And there are numerous entities growing up all around the country right now that are starting these. California is one of the biggest success stories right now.

Here in Montana, we have a big one, the Montana Beaver Conflict Resolution Project that I'm a little bit affiliated with.

Here in Montana, we have a big one, the Montana Beaver Conflict Resolution Project that I'm a little bit affiliated with.

It was a real thing. It did happen in, I believe it was 1948. A lot of interesting things came back after World War II there. And one of the things is that we were really infatuated with air travel and airplanes at the time. And so...

It was a real thing. It did happen in, I believe it was 1948. A lot of interesting things came back after World War II there. And one of the things is that we were really infatuated with air travel and airplanes at the time. And so...

they were trying to figure out the, you know, how to get one of the early solutions has always to beaver conflict problems has always been like, oh, let's just move them somewhere else and do that. And that's still a kind of a gut response for anything from skunks to squirrels to, you know, anything else that we're having a conflict with.

they were trying to figure out the, you know, how to get one of the early solutions has always to beaver conflict problems has always been like, oh, let's just move them somewhere else and do that. And that's still a kind of a gut response for anything from skunks to squirrels to, you know, anything else that we're having a conflict with.

And so they tried on mules with that group of beavers in Idaho. This was outside of McCall, Idaho. And That was not successful for the mules, particularly. They were not very conducive to that. And so they got this idea to release them from the air. And you can find footage of it still, of it happening.

And so they tried on mules with that group of beavers in Idaho. This was outside of McCall, Idaho. And That was not successful for the mules, particularly. They were not very conducive to that. And so they got this idea to release them from the air. And you can find footage of it still, of it happening.

But they did release a number of beavers in these boxes that had straps that would open upon impact with the ground, but not before.

But they did release a number of beavers in these boxes that had straps that would open upon impact with the ground, but not before.

I think it was a few dozen beavers that they released. launched out of the air into this kind of wilder area outside of McCall, Idaho. And they did have one fatality, but over, you know, a couple dozen beavers were dropped out of the sky for that purpose. So reintroduction has a really complex history in different iterations.

I think it was a few dozen beavers that they released. launched out of the air into this kind of wilder area outside of McCall, Idaho. And they did have one fatality, but over, you know, a couple dozen beavers were dropped out of the sky for that purpose. So reintroduction has a really complex history in different iterations.

60, 70 years later, we've realized today how important it is to really relocate beavers as a family unit, because as we've talked about already, they really have strong and complex social bonds. And so it's not effective just to take one beaver and just dump it out in a new place. That beaver is most likely going to suffer and suffer immense risk as well from that relocation.

60, 70 years later, we've realized today how important it is to really relocate beavers as a family unit, because as we've talked about already, they really have strong and complex social bonds. And so it's not effective just to take one beaver and just dump it out in a new place. That beaver is most likely going to suffer and suffer immense risk as well from that relocation.

But when relocated as a family unit, there is potential that they can do well, but again, it is a lot of risk for the animals still.

But when relocated as a family unit, there is potential that they can do well, but again, it is a lot of risk for the animals still.

There is no doubt that as a ketone species, like they are just disproportionately impacting many more lives than we even are aware of at this point. So just knowing what species are in your area and what are thriving, and you can really get a pulse on that yourself too.

There is no doubt that as a ketone species, like they are just disproportionately impacting many more lives than we even are aware of at this point. So just knowing what species are in your area and what are thriving, and you can really get a pulse on that yourself too.

Great question. Yeah. Then what's neat about beavers, in addition to being keystone species for all these countless organisms that inhabit our environment around us, is that beavers are keystone species for all kinds of

Great question. Yeah. Then what's neat about beavers, in addition to being keystone species for all these countless organisms that inhabit our environment around us, is that beavers are keystone species for all kinds of

All just even I mean, the, you know, we've got entomologists and ornithologists and fluvial geomorphologists and all kinds of all just that are coming together to realize, hey, the beaver is like at the nexus of a lot of what we do. And so. I think it's a growing awareness.

All just even I mean, the, you know, we've got entomologists and ornithologists and fluvial geomorphologists and all kinds of all just that are coming together to realize, hey, the beaver is like at the nexus of a lot of what we do. And so. I think it's a growing awareness.

You know, we had so much of the 20th century between the early 1910s or so through the late 1900s, where we, one, just didn't have the eyes to see beavers. And we didn't have the beavers actually physically weren't there. And so they were kind of out of sight, out of mind for a while. But one of the great thinkers that helped reverse that a lot was this guy named Robert Nyman.

You know, we had so much of the 20th century between the early 1910s or so through the late 1900s, where we, one, just didn't have the eyes to see beavers. And we didn't have the beavers actually physically weren't there. And so they were kind of out of sight, out of mind for a while. But one of the great thinkers that helped reverse that a lot was this guy named Robert Nyman.

And he was a hydrologist and ecologist that really showed, wow, beavers had a huge impact on the North American continent. And he was one of the first people to just show, OK, if there were millions of beavers, what kind of water storage did that do? What did that do differently than a concrete dam, that word type of building? And so he looked at a lot of those things.

And he was a hydrologist and ecologist that really showed, wow, beavers had a huge impact on the North American continent. And he was one of the first people to just show, OK, if there were millions of beavers, what kind of water storage did that do? What did that do differently than a concrete dam, that word type of building? And so he looked at a lot of those things.

And and that was in the late 80s, early 1990s when he started doing that. And then another one of his students, Michael Pollack, really took that into the fish realm a little bit and looked at, hey, these coho salmon. They spend 18 months of their life in fresh water when they are in fresh water for that long. The beaver pond is like a nursery pond.

And and that was in the late 80s, early 1990s when he started doing that. And then another one of his students, Michael Pollack, really took that into the fish realm a little bit and looked at, hey, these coho salmon. They spend 18 months of their life in fresh water when they are in fresh water for that long. The beaver pond is like a nursery pond.

for all their their feeding and growth before they go out to sea in these pacific coastal systems and so he did a lot of work with coho salmon and he was actually one of the big guys launching the kind of beaver revolution in 2014 really is when a lot of people really started to take off with this of of just like yes they are answering a lot of things for for fish as well as other species

for all their their feeding and growth before they go out to sea in these pacific coastal systems and so he did a lot of work with coho salmon and he was actually one of the big guys launching the kind of beaver revolution in 2014 really is when a lot of people really started to take off with this of of just like yes they are answering a lot of things for for fish as well as other species

Yeah, good question. So there's some regional variation in that. But generally, beavers in the north are a little bit larger just to have a larger body size to sustain themselves through the winter and have that energy capacity. But I would say an average size would be between 40 to 50 pounds for an adult beaver.

Yeah, good question. So there's some regional variation in that. But generally, beavers in the north are a little bit larger just to have a larger body size to sustain themselves through the winter and have that energy capacity. But I would say an average size would be between 40 to 50 pounds for an adult beaver.

And I am kind of wary myself of just like deification and demonism. We just swing so strongly between these poles of love and hate that I think one of my goals for working with Beaver is really to just integrate them into kind of all we do and just see them as another intrinsically valuable species that we can live with and among.

And I am kind of wary myself of just like deification and demonism. We just swing so strongly between these poles of love and hate that I think one of my goals for working with Beaver is really to just integrate them into kind of all we do and just see them as another intrinsically valuable species that we can live with and among.

And they can really do us a lot of good and we can learn a lot from being with them as well.

And they can really do us a lot of good and we can learn a lot from being with them as well.

one of the great things is that there is no one way to be a beaver or a castorologist. You know, there are many different ways into this. And, and so if you're really into the water angle, the hydrology of it, you know, that's one thing there's lots of opportunity for wildlife biologists and whatnot.

one of the great things is that there is no one way to be a beaver or a castorologist. You know, there are many different ways into this. And, and so if you're really into the water angle, the hydrology of it, you know, that's one thing there's lots of opportunity for wildlife biologists and whatnot.

I think I consider myself a lot of a field ecologist and a wildlife tracker in a lot of ways in that I, and looking at the beaver as one among many of the species that I study. And I'm doing a lot of work to help kind of assess where habitat is good, where potential is good, and inventory and assess those connections.

I think I consider myself a lot of a field ecologist and a wildlife tracker in a lot of ways in that I, and looking at the beaver as one among many of the species that I study. And I'm doing a lot of work to help kind of assess where habitat is good, where potential is good, and inventory and assess those connections.

But just the best way to start getting into it is just to go out to just see if you can find beavers near where you live, and just start watching, observing, and asking questions. And beavers are one of the species that is not endangered today and they don't, at this point, don't have any likelihood of becoming an endangered species, but they are unique and also that they're really accessible.

But just the best way to start getting into it is just to go out to just see if you can find beavers near where you live, and just start watching, observing, and asking questions. And beavers are one of the species that is not endangered today and they don't, at this point, don't have any likelihood of becoming an endangered species, but they are unique and also that they're really accessible.

They can live alongside us if we let them. And so I find that very hopeful in that there are species that so many people wherever they are can really learn from.

They can live alongside us if we let them. And so I find that very hopeful in that there are species that so many people wherever they are can really learn from.

So I do a lot of like habitat and species inventories and assessments. and kind of just trying to sense the life that's out there, so to speak. And one of the more complicated issues that I find a lot of times is with invasive species.

So I do a lot of like habitat and species inventories and assessments. and kind of just trying to sense the life that's out there, so to speak. And one of the more complicated issues that I find a lot of times is with invasive species.

And as we mentioned, beavers are not an invasive species through anywhere in North America, but they can be woven in with species that were not here when they got here. But I'm thinking plants in particular, but reed canary grass, Japanese knotweed are some. And so when those enter in their areas, they can kind of complicate what the beaver is doing because those are not

And as we mentioned, beavers are not an invasive species through anywhere in North America, but they can be woven in with species that were not here when they got here. But I'm thinking plants in particular, but reed canary grass, Japanese knotweed are some. And so when those enter in their areas, they can kind of complicate what the beaver is doing because those are not

But they can get up to, you know, 60 to 90 pounds in some of those areas where they're quite large. And this is not sack of potato size for them at all. It's more along the size of a small dog in some ways, maybe like a border collie, but much lower to the ground, obviously shorter legs, but something along those lines when they're

But they can get up to, you know, 60 to 90 pounds in some of those areas where they're quite large. And this is not sack of potato size for them at all. It's more along the size of a small dog in some ways, maybe like a border collie, but much lower to the ground, obviously shorter legs, but something along those lines when they're

willow rich areas with the nice woody shrubs that they need on. But at the same time, beavers can be sometimes a vector for helping those to spread inadvertently. And so they're just wrapped in this mess that we have made for them that I don't have answers all the time to how to deal with that. But in some areas, riparian invasive species can be pretty tricky with beaver.

willow rich areas with the nice woody shrubs that they need on. But at the same time, beavers can be sometimes a vector for helping those to spread inadvertently. And so they're just wrapped in this mess that we have made for them that I don't have answers all the time to how to deal with that. But in some areas, riparian invasive species can be pretty tricky with beaver.

And it's a really sad thing to see them wrapped into.

And it's a really sad thing to see them wrapped into.

You know, that's a great question. I've asked that of others and myself as well. I kind of go back and forth. I don't have a hard way. I don't think there's an answer to that.

You know, that's a great question. I've asked that of others and myself as well. I kind of go back and forth. I don't have a hard way. I don't think there's an answer to that.

Yeah, I mean, I might sound like it's generalizing too much, but just the sheer feat of existence is really amazing to me. And in the fact that I mean that we talked about winter already and how they survive in these really cold is just a very fascinating thing to me. The fact that, again, they have winnowed down from 33 different genera of beavers to this one genus that survives today.

Yeah, I mean, I might sound like it's generalizing too much, but just the sheer feat of existence is really amazing to me. And in the fact that I mean that we talked about winter already and how they survive in these really cold is just a very fascinating thing to me. The fact that, again, they have winnowed down from 33 different genera of beavers to this one genus that survives today.

And they made it through the gauntlet of the fur trade and all these things. And they are still here persisting and enduring and doing what they do. It blows my mind. There haven't been other animals that have really made it through those type of changes throughout their life history, which is pretty amazing to me.

And they made it through the gauntlet of the fur trade and all these things. And they are still here persisting and enduring and doing what they do. It blows my mind. There haven't been other animals that have really made it through those type of changes throughout their life history, which is pretty amazing to me.

Born, though, they're only about a pound or about the size of a loaf of bread, maybe. You know, that would be a good comparison. For a newborn beaver, it's about a pound.

Born, though, they're only about a pound or about the size of a loaf of bread, maybe. You know, that would be a good comparison. For a newborn beaver, it's about a pound.

Generally two kits, a newborn beaver is called a kit. And so generally two kits per litter, they can have up to four sometimes. The yearlings of that same monogamous pair of male and female will stay on with the family. And so you can have a combination of the two adults and then yearlings from the previous year and then newborns all in one lodge at the same time.

Generally two kits, a newborn beaver is called a kit. And so generally two kits per litter, they can have up to four sometimes. The yearlings of that same monogamous pair of male and female will stay on with the family. And so you can have a combination of the two adults and then yearlings from the previous year and then newborns all in one lodge at the same time.

But by the time they reach two years old, that's typically a natural dispersal time. And so the two-year-olds will leave their natal birth area and strike out to find a new wetland that they can call their own.

But by the time they reach two years old, that's typically a natural dispersal time. And so the two-year-olds will leave their natal birth area and strike out to find a new wetland that they can call their own.

That's a great question. Generally, they stay together for the entire time.

That's a great question. Generally, they stay together for the entire time.

And very social and very territorial against other non-related beavers. They erect a lot of scent mounds, they're called, and they can be up to over a foot wide, a foot tall. And so there are these just heaps of dredged up vegetation and mud from the bottom of the pond or the wetland where they are.

And very social and very territorial against other non-related beavers. They erect a lot of scent mounds, they're called, and they can be up to over a foot wide, a foot tall. And so there are these just heaps of dredged up vegetation and mud from the bottom of the pond or the wetland where they are.

And then they can dollop all their castoreum on top of that, which is a very unique smelling excretion from a particular gland in them. But they can bring that out to put on the castor mound or scent mound, sometimes called to kind of ward off non-related beavers.

And then they can dollop all their castoreum on top of that, which is a very unique smelling excretion from a particular gland in them. But they can bring that out to put on the castor mound or scent mound, sometimes called to kind of ward off non-related beavers.

Well, they definitely do have a particular scent and it's not something that, you know, is out of question to smell yourself. You can definitely find these, especially in the springtime when beavers are actively dispersing that, you know, the same time about when new kits are born is a really important time to kind of mark the territory, so to speak.

Well, they definitely do have a particular scent and it's not something that, you know, is out of question to smell yourself. You can definitely find these, especially in the springtime when beavers are actively dispersing that, you know, the same time about when new kits are born is a really important time to kind of mark the territory, so to speak.

And so these scent mounds are all over the place at that time. And it does have kind of a vanilla-ish tint. I think it's very nice. It's probably dependent on the The nose who's smelling it. And it does have a history of being used in certain products. And, you know, we have used it for perfume and different things. I believe there's schnapps in, is it Germany?

And so these scent mounds are all over the place at that time. And it does have kind of a vanilla-ish tint. I think it's very nice. It's probably dependent on the The nose who's smelling it. And it does have a history of being used in certain products. And, you know, we have used it for perfume and different things. I believe there's schnapps in, is it Germany?

Or I believe it's Germany that uses beaver hot. And it's kind of like a schnapps liqueur that relies on that.

Or I believe it's Germany that uses beaver hot. And it's kind of like a schnapps liqueur that relies on that.

They're kind of artificially synthesized now.

They're kind of artificially synthesized now.

It's not that sharp. It won't be wafting everywhere, but it's very concentrated and localized. And you do kind of know when you hit it when you're kind of near it yourself. But it generally takes leaning down and just kind of getting up close to it. But it's a very nice smell. It doesn't have anything related to scat or urine. They do have a very pronounced anal gland as well. Oh, nice.

It's not that sharp. It won't be wafting everywhere, but it's very concentrated and localized. And you do kind of know when you hit it when you're kind of near it yourself. But it generally takes leaning down and just kind of getting up close to it. But it's a very nice smell. It doesn't have anything related to scat or urine. They do have a very pronounced anal gland as well. Oh, nice.

But that's used for waterproofing. That's not used for the purposes of defending their territory.

But that's used for waterproofing. That's not used for the purposes of defending their territory.

Yeah, I am. And I think that's one of the things that I'm really passionate about is just interpreting beaver landscapes wherever you are. I mean, so many of us on the North American continent live in and among beaver wetlands without even knowing it sometimes. We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us.

Yeah, I am. And I think that's one of the things that I'm really passionate about is just interpreting beaver landscapes wherever you are. I mean, so many of us on the North American continent live in and among beaver wetlands without even knowing it sometimes. We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us.

And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver. And there are things, you know, that we can still see looking at aerial photography, looking at, you know, different ways the land drains that land stacked up.

And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver. And there are things, you know, that we can still see looking at aerial photography, looking at, you know, different ways the land drains that land stacked up.

And that might have been a beaver dam from like a couple centuries ago or something. And so it's really neat to be able to interpret it at that level of history in a contemporary sense. I love being able to kind of know my neighbors, so to speak, of who's building and who's active, who's, you know, it's a very much a dynamic ebb and flow cycle of the beaver. So fun to watch.

And that might have been a beaver dam from like a couple centuries ago or something. And so it's really neat to be able to interpret it at that level of history in a contemporary sense. I love being able to kind of know my neighbors, so to speak, of who's building and who's active, who's, you know, it's a very much a dynamic ebb and flow cycle of the beaver. So fun to watch.

We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us. And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver.

I didn't have like one big light bulb moment. I consider myself very fortunate to, you know, grew up in a family that really supported just my natural curiosities in a lot of ways. And I grew up in the Northeast and spent a lot of time in Northern New York and New England. you know, doing hiking and stuff. And beavers were certainly part of the theme then.

I would spend a lot of time in the woods, saw beavers, but they were just another animal at the time. For me, it wasn't anything like they were changing the world in the way that they do. But I think one of the Kind of milestones for me was going to Isle Royale National Park after college. One of my first wildlife fieldwork gigs was I was helping out with this wolf moose project.

It's called our ostensible purpose was really to track down the bones of moose that were killed by wolves the previous winter. I was there in the summer, and I was just mind-blown with how the beavers had changed the environment there in a way that was not only conducive to the moose, but also really important for supporting the wolves as well.

One of the leaner times for them is in summer, and so I was just fascinated by this is a time when the wolves have adapted to eat beavers as well. I really got to get... A really close look and just appreciate their keystone role is just how complicated and connected and all the things that they do for diverse animals, predators, prey, and everything in between.

And so they're a real integrator of a lot of things. And that's one of the areas where it really lit up for me.

Yeah, thanks. You're welcome. So I think one of the things that is happening is that it is an instinct. There is part of that proclivity to do that instinctually, but it's also a learned response. They've shown how young beavers are actively learning with their parents and watching them and manipulating wood in the same way. And so building a dam is not a necessity for a beaver.

That is not in itself, is not what's necessary.

Beavers are thriving on lake systems where they can have plenty of water. They're on rivers a lot of times where they can bank up in the side of the riverbank without any consequence. And they don't need to build an entire dam across a river or whatnot to have their way. But what dam building does is it is a mechanism for...

extending their safety from predators, but also increasing their access to food. And so when they build a dam in a stream system, it's not only spreading the water out across the stream system laterally, but it's also stacking up a lot of weight behind that dam. And so it's sinking more water into exchange with the groundwater system.

And I think too often we just think of our river systems as one upstream, downstream, going one way. And what's natural about rivers and watershed systems is that when they spread out as well as down, so laterally and vertically as well. And the researcher Ellen Wohl has just done a lot of great work showing that kind of hydrological complexity of beaver systems.

But when the water spreads out, you know, they are very comfortable in water. but not as much on land. You've got to imagine a beaver has front feet that are very dexterous, about the size of a deck of cards or so. And then the hind feet are double or even more than double that size. And they're webbed, entirely webbed.

So it's like walking on hands on one part, but then enormous flippers on the back. And so they're very awkward and just very slow. And they do smell a lot. And so they're very attractive to a number of predators on land. And so being in water is a safe place for them. They're just ultimate graceful in the water. And so that's safe.

And as the water extends, they're both encouraging new like willow, aspen, cottonwood regeneration, and then able to access that for their own food and building uses as well.

Yeah, that's right. A lot of species, wherever beavers were in that range, have co-evolved with beavers and depend on their work and their disturbance factor to make the habitats where they thrive. And so willows are just a consummate example of that. They're

truly an amazing plant in their ability to be you know just a sprig if it's attached you know gets a little bit of a root hold in moist soil can just take off and can propagate very fast in ways that are really great and so Beavers are a little bit different than like an elk or a deer or other browser in that they're not seeking so much the buds. They don't want that just fresh shoot growth.

And so plants like willows, aspens, cottonwoods, those are kind of their... three favorites, really. Those are some of the plants that evolved in those riparian systems that really thrive as well. And so it is a very dynamic cycle. And beavers, they create diversity by being dynamic. One of the things that they do is they don't always stay in that spot.

As one food patch will become diminished a little bit, they'll shift to another. And so at each of those different stages, temporally in the beaver succession, that brings a whole new suite of species that will thrive in that altered state. And so it's a constantly shifting mosaic that beavers really promote.

Yes. I mean, one of the greatest predictors of future beaver habitat is historic beaver presence. And so that's why it's important to have that eye to be able to see where a prior dam complex was or other old chew sign that you can see on sticks and things around. Those are all great signs. for where future beavers could establish as well.

And that's really important for people involved in beaver restoration is looking at kind of where those prior sites were productive because those are the places that they will likely come back to.

Yeah, great question. So it does vary a ton, but generally they are working very hard and in a way very fast on it. Sometimes alterations or blowouts will happen in a dam system naturally or human caused for various reasons. And beavers are very fast to return to that leak and triggered a lot by the sound of flowing water as well. The instinct, that is a trigger to where the leak is, so to speak.

But I also sometimes resist the idea of just the busy being a beaver. If you ever get the chance to watch a beaver doing its work in this setting, they're never frenzied in their activity. I always really appreciate just how deliberate and just like tactful they are in placement. It's more of just like a constant process as opposed to just like this frenzy of activity. And

They have just really mastered the art of maintenance. I think so many of us humans just don't know how to do basic maintenance activities sometimes. We can dispose of something or get a new one, but we don't know how to really just tinker and maintain things over time.

And so I think that's part of what makes beaver structures so resilient is that they're constantly evolving and adapting with the changes that they're facing.

Kind of all of the above. It generally starts with, you know, just some berming of some mud at the base. You know, it's not only stick. So there's some anchoring things in there going on, like the mud. Sometimes even rocks are rolled in and stones can be rolled in as part of like a supporting base. But, you know, it's it is a very complex. And remember, this is in a aquatic environment.

environment where water is flowing around all the time, you don't have the, you know, the ability to do this in dry times, but they use that to their advantage as well. And then as it crests out of the water, you know, they do add a berm of mud, especially on that upstream edge where the water is pounding.

And they will use mud as well to kind of add a little shellac like coating to it to keep it from just water getting through all those crannies of the sticks, so to speak.

Yeah, very much all the above. I think it's not a gendered activity. I think both male and female contribute to dam building and the yearlings as well. It takes the kits a little bit of time to get comfortable to that point. When they're born, they actually don't have their waterproofing gland active yet. And so they stay in the lodge for a little bit of a time.

But after they get that waterproofing gland active and they can be in the water effectively, you know, they will also watch and participate and learn from the process as well.

I believe so. I'm not as familiar with those type of environments, but play and just experimenting and using those tools is very important for

So many animals, you look at bears or wolves or any other animals that are socially oriented like that, that watch each other, learn from each other, and do have play, that play and practicing with their future tools kind of as a very important instinct or way of entering their future work. And so I think that is a possibility, yeah.

Rob Rich, he, him is great.

So definitely not hairy. It is more scaly. So the beaver tail is really a fascinating part of their body in a lot of ways.

Generally not castorologists. There was an early book in the late 1800s that had that name actually, but Generally, it's not castorology. It's either just beaver fans, beaver believers, all the things that are associated with interest and curiosity about beavers.

For one, it's used a little bit as a rudder as they're swimming through the water. And so it can help them steer a little bit. It's also important when they're propping up to chew down a tree or whatnot. And one of the most important functions of it, though, It's a very important alarm system as well.

You've probably either heard yourself or heard of beavers slapping their tail as they get alarmed by predator or potential threat or some other non-related beaver or some other concern in their environment. They will really have this impressive slap.

action on the water, and it is kind of jolting, and that is a warning to other beavers that there might be a threat around, and so they know how to respond to that. But the fourth one that's so important that the tail does is that it's very much a heat or a thermoregulation and heat storage, energy storage organ.

In the winter, that is the part of their body that becomes quite larger than it is in the summer. They have a lot of body fat, but they take on most of that in the winter and store it in their tail.

And so that is really important for one of the ways for them to keep warm in the winter. So the outside is very scaly, always black. And that has also been shown to have a unique signature. You can look at the tail. and tell individual beavers by their tail details, just like we can with a fingerprint on a human.

But then inside of the tail, it's just very thickly layered of white gelatinous kind of fat. And so all that fat is what's really important to further heat storage in the winter.

There is a central node of vertebra extending down through the tail that is in the center of it there, but it's more filled with more capillary like blood vessels. And so there's very lot of blood exchange in there that keeps it from freezing in those times. And again, serving that heat storage purpose. So other than that central area of bone going down the middle, it is entirely fat pretty much.

Sure.

That's kind of the classic at the moment.

Their teeth are supported by a skull that makes their teeth effective. And so they have a very flat-topped, wide skull with these things we call zygomatic arches, which are what we call cheekbones sometimes.

And so when those are so wide spreading, that allows for a lot of muscle attachment coming down over the top of their cranium, attaching to the outside of those cheekbones, and then going down into their mandible. And so... All that complex muscle attachment does make for a lot of jaw strength.

I can guarantee you it's quite strong to bring down to cottonwood or a large tree that is double the size of their body or something.

Yeah, I'm calling from northwest Montana, and I live in a valley called the Swan Valley, a little bit northeast of Missoula and south of Kalispell, up against a part of the Rocky Mountains there and below Glacier National Park. This is a special valley in a lot of ways. It's very well watered.

But the teeth themselves, like all rodents, they're defined by, you know, ever-growing incisors. And so those are kind of the hallmark front teeth that we see. And then they've got a really robust set of molars as well. And so... The molars are for grinding, masticating all that wood pulp down is important. But the incisors are what do the heavy work of the cutting.

And so on the top ones, they're very orange on the outside. And so if you see a beaver's front teeth, you will see that orange that's enamel. And it's colored that way because of some of the iron and the compounds that they eat in the wood that they're having. But that closes over a wider area on the bottom teeth that is called dentine. And so that wider area is softer. The enamel is harder.

When they rub against each other like that, it's a constantly sharpening chisel. And so the beaver's teeth are extremely sharp and constantly becoming more so. And if they don't have access to wood and don't keep gnawing and working on that, then The teeth will keep growing and can become quite a dental hazard for them. So they do require wood for that purpose as well.

But yeah, hard enamel outside, soft white kind of dentine on the inside for those incisors, and then just a lot of continuous action to keep it sharp.

It has a lot of historic beaver activity and current and was also shaped by glaciers, which the beavers actively followed.

Great. So they are definitely 100% vegan. No animal fare of note in maybe an insect or something will slip in occasionally, but there's very minimal to no record of of them relying on any animal food in their diet.

And so in the spring and summer and warmer months when the veg is succulent and there's a lot of herbaceous or non-woody plants out there, there's a number of wetland-associated plants that they will eat. They will also use the roots of certain things, like water lily roots are sometimes important for beavers.

And just in the water lily pad leaves, a lot of those succulent plants are not available, certainly year-round. When they cut down a tree or cut down a branch or whatnot, they're not ingesting the entire thing. They're mostly after what we call the cambium, which is this thin layer of sugary cells where the tree is actively growing. And so most of what we call on a tree is actually dead cambium.

cellulose material. It's not something that is nutritious in any way, but they will seek out that cambium layer just below the bark and below before you get into the real kind of deadwood of the tree. And so they will eat first and then use some for building or some they're just used for feeding as well. A little bit of a mixed bag there.

It's about a golf ball-sized lump a lot of times. And I sometimes liken it to shredded wheat or something. It takes that kind of character. And beetrovers are one of the rodents, in addition to the lagomorphs, the rabbits and pikas and whatnot, that will re-ingest their own first poop. And so they will eat that to kind of extract a second round of nutrients out of it.

This is a practice called coprophagy. Delicious. And so by the time it comes out that second time, it is very loose, easily disintegrated lump of sawdust like shredded wheat. Most of the time it's deposited in water. And so it's very prone to disintegration quite quickly.

In a way, yeah. The last glaciation that covered America was about 10,000 to 12,000 years ago, I believe, as it pocked out a lot of depressional wetlands and carved the rivers in certain ways that made it really conducive to complex flows, which beavers are actively seeking out all the time. And so they find in glaciated regions of North America.

Great. So the two marks are definitely something you want to look for. And if you don't see them and you know there are beavers there, you want to be looking for a cut on the branch at a 45 degree angle. That's just because of how they kind of turn their head and then how the branch typically falls. It's kind of like this...

angled cut, which is typical of all rodents really, but that sharp angled cut is really important. To see beavers, they are, you know, fascinating because they're at once very conspicuous.

You can see their activity from aerial images, which is fascinating, but they're also kind of cryptic sometimes in that they do prefer to be active at nocturnal or crepuscular kind of dawn dusk kind of times sometimes. So a great time is really to just get out there first thing in the morning,

And you can kind of wake up with them as they're about to tuck in for their time kind of in the lodge or their safe spot for the day. And they'll typically come out in the more dusk hours as well. Those are kind of good times to try. But beavers are not hard and fast about being nocturnal. You can find them during the day as well. Yeah.

Yeah, great question. So again, a lodge, you are correct, the lodge is separate from a dam. And so they're not ever living in the dam, but they are definitely using a variety of different lodge styles. And sometimes they can be like freestanding in the water. And sometimes they can be half affixed to like a bank. Sometimes it can just be a hole dug into a bank and they burrowed in that way. But

Those are the places where they're living and kind of sheltering over winter if it's in an environment where they need to do that. And they are not impenetrable, but they are very difficult to enter for a lot of predators. The ones that are made of sticks and mud are generally like the dam in a way. The sticks are kind of latticed in and then the mud fills in a lot of the cracks.

And so when that freezes in the winter, that can become pretty rock hard. And they do all... All the family is living in there together. One of my most fascinating parts of beaver existence is just that time in the winter of how they're doing that under the ice, in the darkness, in cold environments, in wet environments.

And so beavers and glaciers together are two of the major continental shapers of North America.

And it's just, you know, we thought COVID was bad and isolation in a lot of ways. I mean, they are very much isolated in that time when they can't come back out above water surface for months at a time, potentially. It does have... different layers, terraces, a lot of times you can see in them.

If you ever are lucky enough to find a abandoned beaver lodge, sometimes I have been able to enter into some of the chutes that go into a lodge and you can see for yourself kind of what the size is like, but it can generally fit them together, generally some body warmth in there involved.

But Casey McFarland, who's a great tracker and wildlife ecologist, he has a great video just showing one of those abandoned beaver lodges, what the interior is like.

But in the lodges, there can be muskrats, particularly one that are often cohabitating with beavers. And there are things like spiders, all sorts of invertebrates and insects that are certainly dwelling in there, sometimes amphibians as well. And then after the beavers leave sometimes, there can be other larger animals that use them as well.

Sage Raymond is a colleague that has done really neat work up in Elk Island National Park in Alberta, just showing that coyotes and porcupines and different animals are following after the beaver to use those where tree sources are limited. And so beavers are incredibly important throughout, again, throughout their temporal history of their wetland complexes is fascinating to me.

Yes. To survive in the winter, most of the times they're relying on what we call a cache. And so it's like this stored up mass of sticks that they will plug into the floor of the stream or pond or whatever water source they're on. And this is just this raft of sticks that they have piled up and are in the bottom of the water source there. And so that is their primary food during the winter.

Yeah, so that's a great question. You know, the beaver evolution is very complex. And we actually at one time had 33 different genera of beavers and genera like the genus species binomial classification. So we had 33 different types of genus of beaver across the northern hemisphere at one time. And that is totally, at this point, winnowed down to one genus, the genus Castor.

And they're going in and out of the lodge to access that. There is a certain time before freeze up where it's not quite frozen, but it's not quite flowing water everywhere either. So it's kind of that delicate in-between time. And they will use their flat, thick, scald head to kind of bash up through thinner ice to do that and keep it open as long as they can.

But in my area, there does come a point where there is no more of that bashing to be had. And the ice just takes over. And so once that happens, they are fully locked under there for months at a time.

You can tell activity sometimes. One of the fascinating signs to look for is these bubble trails that go in and out. of air escaping from their interstitial spaces of their fur. There's air trapped in there. And so when they go in and out of their lodge, all those bubbles are escaping from their fur and rising up to the surface of the ice.

And so before the ice gets all snowed over and kind of opaque, you can see those bubbles to see where the beavers have been coming and going. But after that, after the snow gets all over the ice, it is pretty much total darkness for potentially a month at a time.

So it is multi-layered as well. It's super dense. It's one of the most dense furs of animals on the planet, really, right up there with sea otter and other semi-aquatic mammals that are spending a lot of time in really cold water in really cold northerly environments. And so it is dense. The layer on the outside that you would touch first is coarser. It's composed of more guard hairs.

That's what waterproofing oils from their anal glands are constantly being lathered onto to keep them as sleek and waterproof as possible. But below that, you get more into some more downy, dense layers that are even softer. And so that is what's kind of right up against their body. The fur is so dense. I've heard it. One stat I seem to recall is like 23,000 hairs per square centimeter.

And so you can imagine a square centimeter. That is not large, but that is a ton of hairs in that area.

And Castor canadensis is the North American beaver, the only one native to this continent. And Castor fiber is the beaver, the Eurasian beaver, and that is over in Europe and parts of Northern Asia as well.

And so that density is probably about 25% of the beaver's insulation through the winter. And so even all that hair, because they're in the water so much, doesn't do all their needs to stay insulated. And that's why they rely so much on their fat stores as well to accommodate the rest of their insulation. But it is incredibly dense fur and it is in the interior very soft. Yeah.

So that varies. The tail, I think, was definitely relied on at certain times in certain people that live in climates where that was needed throughout human evolution. They have certainly relied on beaver tail as a fat source. And beaver meat as well is something that has a lot of importance in certain times of human evolution.

About 33 million years ago, I believe, is when the beavers really started diversifying. And a lot of rodents generally, that was a really time of... rodent diversification. And so we had beavers, one that was kind of more recent times, the castoroides that lived just south of the glacial ice sheets and whatnot.

I can't really speak to what the first listener was talking about, about wrecking the world. I think that would be a little bit extreme. Beavers, like I said, wanted to start here that for seven and a half million odd years, they've been on this continent shaping and transforming it in different ways. And We, at one point, had between 100 and 400 million beavers across North America.

And in the course of about three centuries, in about the 1600s through the early 1900s, that winnowed down to about 100,000 beavers.

And so we are very lucky that they didn't become extinct or endangered. But their populations at this point are very patchy, dispersed, and in many places recovering. But beavers do not need us to keep them kind of their populations in control. I mean, they for all those years, they have had

And so that was one that was about the size of a bear, almost like 175, 200 pounds in a very large beaver. We had beavers, one called paleocastor that actually dug corkscrew-like tunnels with its teeth into what we now know as the prairies of Nebraska. And so very different lifestyle.

Other predators that are doing that effectively and their own population saturation densities is an important regulation on that. And so I think a lot of times where the conflicts come into play is that we are...

living in the same places that beavers also thrive in in other words those low-lying arable flood plains and good soil and all those things where there's good water access and things those are the things people want too and so there's a lot of times some tension there but uh there's a lot of other non-lethal solutions to beaver coexistence as well.

And so a lot of times when that's used as a solution to beaver problems, that's really just creating a void for new beavers to come in. Because again, if the habitat is good, future beavers will find that and be a part of that somehow.

No, you're right. Not as prolific as other rodents, for sure. And only one litter per year. And they generally are mating in late winter, January, February, and then having their kits in May, June, around that time. So yeah, mice and voles and other rodents that are much more prolific than beavers are. So they're not that prolific, really.

Wow, great question and great observation. I think I do not have the answer to that, but I do know that beavers do play and I do know that there are interspecies interactions, intraspecies interactions that we are constantly learning about. And that's one of the areas that I'm most fascinated by is the beavers themselves, but also how they're shaping and interacting with

all kinds of species from the butterflies that are attracted to the sap on the branches they cut to other things they're swimming around. And so I can't say it's a regular thing that beavers and ducks are playing together, but I would not doubt that there's possibility for interaction there that I've not observed either.

For sure. Yeah, they're really central to the work I do and I'm a part of tangentially and directly. The Beaver Deceiver is kind of pioneered and patented by this guy named Skip Lyle, really brilliant guy based out of Vermont currently.

But he grew up around just watching trapping take place and whatnot and was like, sure, there had to be a better way than just this remove and fill the void, just this never-ending cycle. that all kinds of road crews and private landowners and public agencies are dealing with.

Sometimes culverts, you know, those big pipes that go under a road to allow the stream through, you know, to a beaver, that is just like a ready-made dam with a hole in it. And so beavers are always plugging these culverts with their sticks and mud and whatnot and causing a real headache for a lot of those people.

But it wasn't until they really converged on that semi-aquatic behavior and the wood cutting and dam building behaviors. When all three of those parts converged in the Beaver, that is what drew their evolutionary success. And that's kind of the one that's persisting today.

And so the beaver deceiver is one way to exclude them from these high conflict areas like culverts. In its simplest definition, it's kind of like a fence that goes around the culvert to exclude that, but you want to do it at the right angle and the right distance and the right site-specific ways that it's effective. And so... Skip Lyle kind of pioneered that.

But then there's also some like flow device things that are kind of like a pipe that we put through a dam that can siphon water through a dam from upstream to downstream. And so that allows people to kind of strike a compromise with the beaver in the sense that they can still stay there, they can still have their dam and still have all the benefits to their ecology there.

But the water level can be lowered just enough where it's not as much of a headache for other people that are worried about getting flooded out or that type of thing. And there are numerous entities growing up all around the country right now that are starting these. California is one of the biggest success stories right now.

Here in Montana, we have a big one, the Montana Beaver Conflict Resolution Project that I'm a little bit affiliated with.

It was a real thing. It did happen in, I believe it was 1948. A lot of interesting things came back after World War II there. And one of the things is that we were really infatuated with air travel and airplanes at the time. And so...

they were trying to figure out the, you know, how to get one of the early solutions has always to beaver conflict problems has always been like, oh, let's just move them somewhere else and do that. And that's still a kind of a gut response for anything from skunks to squirrels to, you know, anything else that we're having a conflict with.

And so they tried on mules with that group of beavers in Idaho. This was outside of McCall, Idaho. And That was not successful for the mules, particularly. They were not very conducive to that. And so they got this idea to release them from the air. And you can find footage of it still, of it happening.

But they did release a number of beavers in these boxes that had straps that would open upon impact with the ground, but not before.

I think it was a few dozen beavers that they released. launched out of the air into this kind of wilder area outside of McCall, Idaho. And they did have one fatality, but over, you know, a couple dozen beavers were dropped out of the sky for that purpose. So reintroduction has a really complex history in different iterations.

60, 70 years later, we've realized today how important it is to really relocate beavers as a family unit, because as we've talked about already, they really have strong and complex social bonds. And so it's not effective just to take one beaver and just dump it out in a new place. That beaver is most likely going to suffer and suffer immense risk as well from that relocation.

But when relocated as a family unit, there is potential that they can do well, but again, it is a lot of risk for the animals still.

There is no doubt that as a ketone species, like they are just disproportionately impacting many more lives than we even are aware of at this point. So just knowing what species are in your area and what are thriving, and you can really get a pulse on that yourself too.

Great question. Yeah. Then what's neat about beavers, in addition to being keystone species for all these countless organisms that inhabit our environment around us, is that beavers are keystone species for all kinds of

All just even I mean, the, you know, we've got entomologists and ornithologists and fluvial geomorphologists and all kinds of all just that are coming together to realize, hey, the beaver is like at the nexus of a lot of what we do. And so. I think it's a growing awareness.

You know, we had so much of the 20th century between the early 1910s or so through the late 1900s, where we, one, just didn't have the eyes to see beavers. And we didn't have the beavers actually physically weren't there. And so they were kind of out of sight, out of mind for a while. But one of the great thinkers that helped reverse that a lot was this guy named Robert Nyman.

And he was a hydrologist and ecologist that really showed, wow, beavers had a huge impact on the North American continent. And he was one of the first people to just show, OK, if there were millions of beavers, what kind of water storage did that do? What did that do differently than a concrete dam, that word type of building? And so he looked at a lot of those things.

And and that was in the late 80s, early 1990s when he started doing that. And then another one of his students, Michael Pollack, really took that into the fish realm a little bit and looked at, hey, these coho salmon. They spend 18 months of their life in fresh water when they are in fresh water for that long. The beaver pond is like a nursery pond.

for all their their feeding and growth before they go out to sea in these pacific coastal systems and so he did a lot of work with coho salmon and he was actually one of the big guys launching the kind of beaver revolution in 2014 really is when a lot of people really started to take off with this of of just like yes they are answering a lot of things for for fish as well as other species

Yeah, good question. So there's some regional variation in that. But generally, beavers in the north are a little bit larger just to have a larger body size to sustain themselves through the winter and have that energy capacity. But I would say an average size would be between 40 to 50 pounds for an adult beaver.

And I am kind of wary myself of just like deification and demonism. We just swing so strongly between these poles of love and hate that I think one of my goals for working with Beaver is really to just integrate them into kind of all we do and just see them as another intrinsically valuable species that we can live with and among.

And they can really do us a lot of good and we can learn a lot from being with them as well.

one of the great things is that there is no one way to be a beaver or a castorologist. You know, there are many different ways into this. And, and so if you're really into the water angle, the hydrology of it, you know, that's one thing there's lots of opportunity for wildlife biologists and whatnot.

I think I consider myself a lot of a field ecologist and a wildlife tracker in a lot of ways in that I, and looking at the beaver as one among many of the species that I study. And I'm doing a lot of work to help kind of assess where habitat is good, where potential is good, and inventory and assess those connections.

But just the best way to start getting into it is just to go out to just see if you can find beavers near where you live, and just start watching, observing, and asking questions. And beavers are one of the species that is not endangered today and they don't, at this point, don't have any likelihood of becoming an endangered species, but they are unique and also that they're really accessible.

They can live alongside us if we let them. And so I find that very hopeful in that there are species that so many people wherever they are can really learn from.

So I do a lot of like habitat and species inventories and assessments. and kind of just trying to sense the life that's out there, so to speak. And one of the more complicated issues that I find a lot of times is with invasive species.

And as we mentioned, beavers are not an invasive species through anywhere in North America, but they can be woven in with species that were not here when they got here. But I'm thinking plants in particular, but reed canary grass, Japanese knotweed are some. And so when those enter in their areas, they can kind of complicate what the beaver is doing because those are not

But they can get up to, you know, 60 to 90 pounds in some of those areas where they're quite large. And this is not sack of potato size for them at all. It's more along the size of a small dog in some ways, maybe like a border collie, but much lower to the ground, obviously shorter legs, but something along those lines when they're

willow rich areas with the nice woody shrubs that they need on. But at the same time, beavers can be sometimes a vector for helping those to spread inadvertently. And so they're just wrapped in this mess that we have made for them that I don't have answers all the time to how to deal with that. But in some areas, riparian invasive species can be pretty tricky with beaver.

And it's a really sad thing to see them wrapped into.

You know, that's a great question. I've asked that of others and myself as well. I kind of go back and forth. I don't have a hard way. I don't think there's an answer to that.

Yeah, I mean, I might sound like it's generalizing too much, but just the sheer feat of existence is really amazing to me. And in the fact that I mean that we talked about winter already and how they survive in these really cold is just a very fascinating thing to me. The fact that, again, they have winnowed down from 33 different genera of beavers to this one genus that survives today.

And they made it through the gauntlet of the fur trade and all these things. And they are still here persisting and enduring and doing what they do. It blows my mind. There haven't been other animals that have really made it through those type of changes throughout their life history, which is pretty amazing to me.

Born, though, they're only about a pound or about the size of a loaf of bread, maybe. You know, that would be a good comparison. For a newborn beaver, it's about a pound.

Generally two kits, a newborn beaver is called a kit. And so generally two kits per litter, they can have up to four sometimes. The yearlings of that same monogamous pair of male and female will stay on with the family. And so you can have a combination of the two adults and then yearlings from the previous year and then newborns all in one lodge at the same time.

But by the time they reach two years old, that's typically a natural dispersal time. And so the two-year-olds will leave their natal birth area and strike out to find a new wetland that they can call their own.

That's a great question. Generally, they stay together for the entire time.

And very social and very territorial against other non-related beavers. They erect a lot of scent mounds, they're called, and they can be up to over a foot wide, a foot tall. And so there are these just heaps of dredged up vegetation and mud from the bottom of the pond or the wetland where they are.

And then they can dollop all their castoreum on top of that, which is a very unique smelling excretion from a particular gland in them. But they can bring that out to put on the castor mound or scent mound, sometimes called to kind of ward off non-related beavers.

Well, they definitely do have a particular scent and it's not something that, you know, is out of question to smell yourself. You can definitely find these, especially in the springtime when beavers are actively dispersing that, you know, the same time about when new kits are born is a really important time to kind of mark the territory, so to speak.

And so these scent mounds are all over the place at that time. And it does have kind of a vanilla-ish tint. I think it's very nice. It's probably dependent on the The nose who's smelling it. And it does have a history of being used in certain products. And, you know, we have used it for perfume and different things. I believe there's schnapps in, is it Germany?

Or I believe it's Germany that uses beaver hot. And it's kind of like a schnapps liqueur that relies on that.

They're kind of artificially synthesized now.

It's not that sharp. It won't be wafting everywhere, but it's very concentrated and localized. And you do kind of know when you hit it when you're kind of near it yourself. But it generally takes leaning down and just kind of getting up close to it. But it's a very nice smell. It doesn't have anything related to scat or urine. They do have a very pronounced anal gland as well. Oh, nice.

But that's used for waterproofing. That's not used for the purposes of defending their territory.

Yeah, I am. And I think that's one of the things that I'm really passionate about is just interpreting beaver landscapes wherever you are. I mean, so many of us on the North American continent live in and among beaver wetlands without even knowing it sometimes. We have this issue, I think, as a people, just of beaver amnesia, not being able to see what the beavers created before us.

And I would bet, you know, almost the entirety of us that are drinking water and flushing toilets and taking showers and all the things, our water is coming from somewhere that at some point in its history was shaped by a beaver. And there are things, you know, that we can still see looking at aerial photography, looking at, you know, different ways the land drains that land stacked up.

And that might have been a beaver dam from like a couple centuries ago or something. And so it's really neat to be able to interpret it at that level of history in a contemporary sense. I love being able to kind of know my neighbors, so to speak, of who's building and who's active, who's, you know, it's a very much a dynamic ebb and flow cycle of the beaver. So fun to watch.