Beavers are keystone species that function as ecosystem engineers, creating wetlands through dam-building that transforms landscapes, increases water retention, and supports diverse wildlife including moose, trumpeter swans, and over 200 bird species; their populations were nearly decimated by fur trappers in the 19th century but are now being restored through conservation efforts using beaver dam analogs to help recover damaged riparian habitats.
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Beavers: The Most Important Animal in Yellowstone? | Dennis Quaid: Saving YellowstoneAdded:
You know, it's nice to be up in this high country.
Sitting by a quiet pond like this just helps you [music] find peace, reconnection with nature.
And when I'm up here in this gorgeous valley I used to call home, I find a real serenity.
When I first came up here, I'd sit around the campfire where the old friends and we just sort of take it all in. We'd howl at the moon, look at the stars in the sky, listen to the sound of the streams.
Quiet language of mother earth.
You know, we don't think about where water comes from, do we? Rivers and creeks.
They're there our whole lives, but they're always moving and forming and flowing.
They [music] carve paths through these mountains, and they nourish every creature.
Rivers are what brought Lewis and Clark into this area more than 200 years ago.
It was colder then.
It's getting hotter these days.
Water is scarce [music] in many parts of the West, especially right here in Yellowstone.
For every living thing here, we have to find ways to keep the rivers and streams flowing. And scientists like Doug Smith and the folks at the Monteth Shop feel that the answer may have been right here in front of us all along.
In July of 1805, the Lewis and Clark expedition reached the Yellowstone ecosystem.
Merryweather Lewis described the waterways that cut through the pristine lands as dotted with beaver dams succeeding each other in close order and extending far upstreams.
There were little green islands of life [music] dotting the rivers.
He described the water as cold and pure.
The waters produced a luxurant growth of weeds, trees, and grasses.
The Yellowstone region has changed dramatically since the time of Louiswis and Clark.
Its rivers have been tamed.
Its streams have dried up. And the green islands that once dotted its waterways [music] have disappeared.
[music] But what once was could be again.
Water is the key to life in the wild.
And [music] one animal with a little help from modern-day settlers could be a solution for the 21st [music] century wild west.
[music] When the snow begins falling and temperatures plunge below zero.
Life slows down across the landscape.
But not even a month's long freeze can stop the Yellowstone River from flowing.
The 692m [music] long waterway is the largest undammed river in the lower 48 states.
And it feeds numerous streams and wetlands.
[music] And during this time of year, it provides a safe harbor to countless animals, including one very special family of mammals.
It's a full house in this [music] Beaver Lodge.
Mom and dad are supporting [music] three yearlings and four newborns.
Even in a well stocked lodge like [music] this, supplies and space are limited.
The beavers [music] will hold out here until the spring thaw.
What their lodge lacks in creature comforts, it more than makes up for [music] in clever design.
There is a dry area, a place for food storage, and multiple entrances.
Mom and dad have little time to [music] rest.
The newborns are still nursing.
The yearlings, however, well, [crying] toddlers will be toddlers.
They're always underfoot.
In a few months, this family will emerge from their seclusion, and that [music] day will be an important one for the entire ecosystem.
The wetlands [music] that support this habitat are their creation, and they haven't finished their handiwork.
Fresh water is the key to life for everything in Yellowstone.
Here, the headwaters of seven major rivers rush down from the continental divide and flow into America's west.
the Lamar, Snake, Fire Hole, Jefferson, [music] Madison, Gallatin, and the largest, the Yellowstone.
These same rivers feed over 150 lakes and 278 identified streams.
Over time, they've carved natural boundaries into the landscape.
But those boundaries didn't last.
When the waves of European settlers arrived, they reshaped the West, bending the land and the water to their will.
creating a land of opportunity [music] for some and limiting resources for others.
Beavers were nearly wiped out.
The animals [music] that relied on their ponds suffered.
Those same challenges, increasing temperatures [music] and a rising population still persist.
Beavers, however, are making a welcomed comeback. And with them, they bring [music] hope.
Few people [music] know Yellowstone's wildlife like Doug Smith. For 28 years, he worked as a [music] scientist at Yellowstone National Park. He was involved in predator management and was part of the team that reintroduced [music] wolves into the region.
People know me as the wolf guy, but maybe the hidden [music] secret to my life is I also studied beavers for 11 years.
His current [music] work brings him back to his earlier passion.
[music] Beavers really are a creature of the lake states, Minnesota, Michigan, Wisconsin, but beavers really across North [music] America can exist any place there's fresh water and the [music] gradient for them to make their dams and ponds isn't too steep.
So studying beavers for a good part of my career, what I've learned about them is they're often overshadowed by more charismatic [music] other critters.
And to study beavers, it causes you [music] to study history.
Beavers drove the exploration and settlement of North America.
Some people call it brown gold.
That's how important they were. And so these fur trappers [music] were infiltrating all the rivers and streams and mountains all across the North American continent looking for beavers.
The downside was we virtually wiped them out across the continent. And so that changed ecosystems almost irreoverably.
And when you fly over a landscape that [music] has no beavers, it's narrow and the streams flow straight [music] and it it it doesn't look that vibrant or verdant.
>> Today, beaver numbers are healthy, but nowhere near where they were centuries [music] ago.
>> And so that impact that they had was gone, and it's just starting to come back now.
people realize what this critter, this rodent [music] did.
He continues research at the Jackson [music] Fork Ranch, and he's keen to see how riparian habitats on the property are doing. If Doug is lucky, he'll find a beaver lodge and its inhabitants. An active lodge means good things for the animals who [music] call the area home and good things for the ecosystem.
When spring arrives, the region's grasses [music] come to life.
The balsam root and larkspur bloom, and the season's warmth draws out the ecosystem's color and energy.
The beavers feel the change in the air as well.
And after a long winter huddled indoors, they are [music] ready to get back to work.
Even though they'd been well provisioned in their lodge with four nursing kits, the mom needs more to keep up.
Those kits will remain in the den for another one [music] to two months, suckling from their mother while slowly transitioning to solid food.
The older kids, now in their second springtime, will work alongside their parents, helping with day-to-day tasks like foraging for food, reinforcing the dam and lodge, and protecting the family unit.
Family bonds are strong.
Mom and dad prepared well for [music] winter. Everyone is hearty and healthy.
Newly flowering trees are an irresistible treat for the Beaver Clan.
The willow trees down by the wateride are some of the first to bloom in this ecosystem. Their male and female flowers appear separately early [music] in the spring as catkins, often before the leaves emerge.
Willow trees thrive in and around [music] the banks of Yellowstone's rivers and streams, and they are a key to this beaver family's success.
After a few touchups, [music] this family's home is looking good. They are ready for the hot, dry summer ahead.
The melt water trickling down from high in the mountains fills the local streams and ponds with fresh water. This steady supply hydrates the ecosystem from flowers to towering trees, from the tiniest insects to the largest mammals.
This moose is fine by the water. He's not worried about getting his hooves wet.
In fact, he's an excellent swimmer. He can hold his breath underwater for up to a minute.
Moose are the largest, tallest, and heaviest members [music] of the deer family. In North America, bison are the only land mammal that outweighs him.
He's shedding his winter fur, giving him a bed look. Not that he's too concerned about it.
Moose don't lack confidence.
He seeks a favorite meal, willow trees.
He achieved his grand stature by eating plants. A lot of plants. Moose consume 40 to [music] 60 lbs of food daily.
That's around 16,000 calories.
They can quickly clear a grove from top to bottom. He'll feed on this willow as [music] long as he feels cool and as long as he feels safe.
Mountain lions, [music] bears, and wolverines hunt moose, but their most feared predator is the wolf.
A study in 2001 showed that moose were naive about the threats [music] they faced when they found themselves in more predator dense environments.
Now what does that [music] mean in a place like Yellowstone where wolves were reintroduced within just the last [music] 30 years? Before the wolves return, moose and other ungullets would clear entire groves of [music] trees.
But now that wolves [music] have returned to their habitat, moose have been forced to change their habits and as a result no longer overgraze [music] valuable riparian habitats.
Moose populations are lower than they should be in Yellowstone.
Factors [music] like the 1988 wildfires and increasing temperatures have impacted their numbers.
But one team of scientists think they can help moose bounce back by supporting [music] one of the animals key allies.
Kevin Monteth from the University of Wyoming is very familiar with Yellowstone's [music] valleys and waterways.
His research group, the [music] Monteth Shop, studies various animals that call this landscape home.
>> So, a few yards, probably anywhere in here, she should have beded down this morning.
>> Today, his research has led him to this wetland habitat.
>> Let's scope around and see if we can find her bedside. Okay. We had her here at 3ish.
>> 3:00 a.m. Yep.
>> With graduate student Macy Jacobson.
They're looking for a moose resting spot.
>> Something unique about moose compared with most other big critters like themselves is they're very large, have dark pelage, and they lack any [music] ability to sweat. When we take that and consider moose habitat, especially within the lower 48, and we think about these repairarian complexes and the affinity for moose to be present within them, our focus has been on those willow communities as a source of food and sustenance.
That brought us to the place where we began to think about what role beavers may play within these [music] repairarian communities because of how they alter the environments that they live in and they increase water retention and potentially as a consequence of the dams that they build and the and the backfilling in the water [music] that it creates in various areas. You yields much greater opportunity in places for moose to be able to bed down and uh seek that thermal [music] refuge. It may sound like an unusual pairing. A massive moose alongside a [music] swimming rodent, but that little rodent can do wonders for the moose's survival.
>> We already know that they're ecosystem engineers. We know they make great change in the environments they live in.
But of what change that they are causing, what does it mean for moose?
and what does it mean in particular for moose food and their [music] thermal environment?
>> Kevin and his team have devised a clever way to track how moose interact with riparian habitats.
>> So, the moose we're working with are are fitted with GPS collars that uh send us hourly locations multiple times a day.
From those hourly GPS locations, it allows us to know where the animals are, what they're doing, but then also be able to identify places on the landscape that they're spending uh more time or specific spots where they're spending an increasing amount of time that would be associated with a [music] bed site.
>> The data revealed by the collars give scientist a oneofa-kind glimpse [music] into a moose's life. Our collars that these moose are wearing are fit with cameras as well. The collar is activated once the animal gives birth. And then from the time they give birth, uh, at least up until wintertime, what we're getting are basically 15-second clips of what the animal is doing in conjunction [music] with each hourly location during daylight hours. The power of that is it yields some pretty fascinating footage for us to be able to peer into animal behavior and what they're doing. But in addition to that gets us a sense of uh their feeding patterns, what these animals are eating that we can then use to quantify diet.
>> The research measures the impact of a healthy wetland [music] habitat for beavers and moose.
>> In this area right in here, as we see with the various this the small dams that exist along this drainage are creating a lot of backpooling of water that are basically expanding the options. As you might think about a drain is that's just a focused drainage point where the water only runs down through it and the beaver dams help back up that water and create more music areas that are substantial thermal refuge for moose.
>> It stands to reason that an animal built to survive Yellowstone's winter would struggle to stay cool and even hotter summers. But there is more to the story.
Sometimes we have to quantify the obvious if we're going to be able to put the right messaging around it and create the hook that can result in change. And when we're talking change, that's largely changed for [music] us in our behavior and what we're willing to accept or not. There's fresh droppings right here. This is definitely from her uh this morning. There's some brow leaders here. This was right in her area where we're searching for a bed. We're not coming up with a bed site. So, probably just down here feeding and didn't actually bed down this morning. I think with this it's it's necessary to create some momentum behind not only what we can do for moose, but how we may be able to use a critter that isn't appreciated to the level that I don't know, maybe they should be. Kevin and Macy will study this habitat for another few years. The information they gather will help not only scientists but also the community at large.
We're working with land owners who have recently realized [music] the potential for beaver to improve the habitat on this property, not just for moose, um, but for fish, birds, their livestock. I think diving into the, you dimension side of it and learning how people are living alongside them successfully so that we can implement that broadly across the landscape [music] so that we can continue to recover to the species.
>> [music] >> While the moose continue grazing, the beavers build up their lodge and gather provisions.
The dam they built is strong and has created a large pool behind it, a new aquatic [music] habitat.
A beaver pond like this quickly becomes the go-to spot for local fauna.
Land creatures [music] come to drink.
Fish multiply in [music] its tangled shallows.
Insects are drawn to the moisture while birds discover a new feeding area stocked with fish and bugs they like to eat.
And these birds aren't alone. Raptors, water fowl, over 200 species of birds in all, 70% of them depend on the area's waterways for survival.
One bird in particular [music] appreciates the efforts of the beaver.
The trumpeter swan.
The majestic [music] gliders are renowned for their beauty and fidelity and of course their unmistakable call that inspired their name.
Like all trumpeter swans, this pair will mate for life.
But unlike others, these swans will pass up a chance to migrate, staying here in Yellowstone year round.
They are highly adaptable, tolerating both the intense cold and heat of Yellowstone seasons.
This swan [music] and his mate have already bonded.
Within the next few months, they will establish a nest and begin caring for their eggs. These birds are the largest waterfell in North America, but that [music] doesn't mean they are safe from predators.
They need a home that will comfort and protect them.
Enter the beaver.
Beaver dams are the ideal spot for a trumpeter swan nest. They are tucked away near forest and built solid, offering protection from predators.
More beaver dams offer much needed nesting spots [music] for swans at a time when climate change threatens other ideal locations.
Now that they have found their perfect home in the wild, all that is left to do is fill it with a few trumpeting [music] signets.
Over at the Jackson Fork Ranch, Doug Smith has his eyes on local repairarian habitat.
and ATV is the best mode of transportation despite his misgivings. [music] Love visiting beaver drainages.
Not sure about this thing though. I'm used to walking up or actually paddling up. But nonetheless, however you get here, these are cool areas. You can see the influence of the water impoundment.
So, this is just really a vibrant area.
I'm just going to get down here to take a closer look at what's going on.
Well, this is a classic beaver impoundment.
Some call them dams.
Lewis and Clark, especially Marweather Lewis, marveled at their construction.
We've got mud, sticks, rocks. They'll use whatever they can to make these dams. Without the beavers, this little stream valley is a a different world. It raises the water table. They slow it down. They impound it so it spreads out.
And these willows, all the hydraologists I know talk about these willows, their feet are in the water.
And they spread out much more when the beavers are here. So you get a flood plane. And that flood plane is rich in nutrients in the soil because of beavers empowerment over time. It grows vegetation which grows wildlife both birds, mammals, fishes, reptiles, amphibians. It just transforms this site into a completely different system when you've got this beavers. [snorts] You know, it's funny. I taught my kids how to fish in the same [music] pond.
I think they just like splashing around in the water more than anything.
We take it for granted, but water, it really is the essence of all life. And that includes the Yellowstone ecosystem.
This area just wouldn't be the same without its waterways.
And as the coming of summer starts the snow melt, that means the rivers and lakes are running high. And for one of the world's most industrious herbivores, it's the start of one of the busiest time of the year.
Woohoo!
The Beaver Clan is enjoying the fruits of the summer.
Trees are plentiful.
There is an abundance of food to feed on.
Beavers are herbivores.
During the spring and summer months, they prefer leaves, grasses, water liies, roots, rushes, and other [music] plant life.
But as winter nears, their taste [music] turn to tree bark.
The key to managing this varied diet lies in the beaver's gut.
A complex [music] microbiome inside its digestive system can ferment wood, extracting nourishment.
The mother beaver has successfully weaned her pups.
They are now old enough to explore their aquatic garden all by themselves.
The father has gone out for some lumber.
The roof is leaking, meaning their dry space is not quite as dry as it needs to be.
And then there are the tunnels.
Never ending, always fixing the tunnels.
Until he gets these repairs done, they'll face risk to their pantry and safety.
The tunnels branch out from the main quarters and offer multiple gateways into the lodge, plus easy escape routes from predators.
But these corridors also serve a [music] larger purpose for the ecosystem. The tunnel broadens the dam's footprint, which allows the pulled water to seep deeper into [music] the ground. This fills the water table and preserves [music] water longer into the season.
Beaver lodges, dams, and tunnels have the power to manage both floods [music] and droughts.
The water preserved by beaver dams is key to riparian habitat [music] growth and sustaining the ecosystem.
By the end of the 19th [music] century, the beaver population had been decimated across the western [music] states. Their numbers have increased, but man has built on ideal beaver [music] habitat.
The geological need for their engineering never stopped.
Scientists realized that more dams [music] could help prevent drought.
The Montana Conservation Corps works [music] closely with other nonprofits and government agencies to restore habitats across the state, including riparian areas.
>> I think it's really hard to look at a landscape and say this is what it used to look like a 100 years ago, but there's evidence and [music] there's signs. there were beaver in the prairie and there still are, but more than likely there was more. And there's been more and more evidence that shows that.
Really old dams, lots of old growth cottonwood where you can just tell it used to be a very complex braided wet system with a wide valley.
>> Today, an MCC team is just outside Lewistown, Montana, working on a long-term [music] restoration project.
The whole purpose is to look at a system, pick out some areas that might need our assistance. Insized stream banks, high erosion, disconnected from the [music] flood plane, narrow streams.
It just seems out of funk and cannot restore itself [music] or manage its energy appropriately. And BDAS or beaver dam analogs, they're definitely the most popular one as they mimic natural beaver dams.
When we build the beaver dam analogs, they're channel spanning structures. So, at the time that we built them, it was from one end of the channel to the other. So, as you look at that one right there, you could see where the original channel used to be, indicated by our posts. But this dam has done a really good job of widening the stream. It's slowed things down. It's not very narrow and fast moving anymore. It's spread out. And one thing you'll see is a ton of sediment just deposited. So, lots of soil deposition happening, which is what we want. Their goal to create a healthier landscape that benefits both humans and the wild throughout the state and the project is already seeing results.
And in this reach specifically, it was chosen because of the willow patch that is over there. So, we knew that we wanted to try and enhance what was already there with the willows. That was last summer. So, now we're on year two of implementation.
And it didn't even take a year for a beaver to move in. So right now within this system, Buffalo Creek is on this ranch for 7 miles and then it flows into state land. And on state land, there's a whole colony of beavers. And I don't think any of us really anticipated that it would happen that fast from more than likely a beaver from that colony to swim up here and establish where we have about 20 or so of our BDA structures. If they are successful, the work of these conservationists will one day give way to Yellowstone's original landscape engineers, beavers, whose work in turn will refresh and feed populations of willow, moose, and water fowl. perhaps bringing us closer to the vibrant, resilient landscape described by Lewis and Clark more than two centuries ago.
As summer nears its end, water becomes increasingly precious.
The snow melt is all but gone. Until the next snowfall, the ecosystem must be supported by the rivers and creeks alone.
For most ungulates, the decreasing temperatures are a signal to begin a long annual migration.
But not the moose.
They prefer to stay close to [music] the river close to the willow trees and other familiar food sources.
This moose will likely seek a mate in [music] the coming months. The question will be whether he has the strength to take on older, [music] more powerful bulls.
But mating is a far cry from his present concerns, eating and staying cool.
And no place is better at cooling a hungry moose than a beaver pond.
So, I want to check this beaver pond out. There's a lodge over there.
So, a beaver families living here.
That's usually five, six, seven individuals.
So, this beaver pond here is kind of a classic example of how beavers impact the hydraology of this entire valley.
So if [music] they weren't backing up this water, this water just be lost downstream and into the river and and gone. The beavers come through, they occupy this spot, they dam it, they pond it, they preserve the water and raise the water below for many things to benefit. So these beavers are transforming this landscape for the better or I would say the way it should be and the way it was.
This is an active sight for sure.
Everything in [music] life is little times more.
This family, the young are going to leave and they're [music] going to go over that hill and they're going to do this over there. And so this is multiplied over and over and over. And so this becomes a different valley with [music] these beavers.
Fresh cutings.
There's an entrance right here. So a tunnel goes in the lodge and up into it.
There's usually a platform inside. So they're out of the water. Very important in the winter so they can get in.
There's another entrance over there.
Fresh cut stick.
This hasn't been barked because in the summer they're not going to eat bark.
They're going to eat the leaves, the succulent vegetation. They'll go up onto shore. The herbaceious succulent stuff.
They'll graze just like a a deer or an elk will.
It's really a cool spot.
They transformed ecosystems, keystone species. So they come in in their quiet, unassuming way and [snorts] everything explodes [music] and becomes healthier, a a more intact ecosystem.
And it's taken hundreds of years because the [music] devastation the fur trade inflicted upon the beaver population was that severe.
And so now this unsung [music] rodent is getting the credit that they deserve and people are beginning to bring them back and people are using them to restore these damaged [music] landscapes. They do all the work. It really is a remarkable story, almost an ecological [music] miracle. We didn't think we could, but we really can't coexist with beavers.
They're that important for us and for them.
With winter nearing, the animals of the Yellowstone region turned their focus to surviving the coming cold.
Angullets like elk, bison, and moose work to gain as much [music] weight as possible.
Some of the water foul have already begun their migration to warmer environments.
The beaver family remains as busy as ever.
With their summer renovations complete, they've turned their attention back to stocking their larder.
With their tunnels reinforced and their storage pockets packed with food, the family is ready [music] to show their young kids what it takes to survive a Yellowstone winter.
But this coming season, the family will have three fewer mouths to feed.
The yearlings will leave [music] the lodge intent on establishing homes of their own.
If life goes to plan, they will find [music] mates and they will build dams that will be much more than just a home.
They will support [music] a habitat and the entire Yellowstone ecosystem.
This time of day, it always seems to conjure up old memories, old friends, childhood, dreams about life.
It's all right here.
You feel a real energy in country like this. And the waterways here are part of that energy, the source of all life.
Here in Yellowstone, the rivers and creeks are the central nervous system of an entire multi-state ecosystem.
They are what makes this habitat sustainable for all of the life here, every human, every animal.
So long as we keep these waters flowing the way nature intended, we can help protect this truly wonderful environment.
The Yellowstone ecosystem, a rugged, iconic, one-of-a-kind place. But this landscape [music] is under threat. The fight is on to protect it. Find out more at saving yellowstone.org.
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