“The global-scale decline of animal biodiversity [defaunation] represents one of the most alarming consequences of human impacts on the planet.”
That’s the opening statement from a study published in the scientific journal,Biological Reviews.
In southeastern North Carolina, large swaths of trees are disappearing. What was a natural area, buffering one neighborhood from another, can vanish entirely between sunup and sundown as humans driving tree removal machines scrape everything away down to the dirt.
The ground is now a canvas for a new building. And the vegetation that lived there is pushed into a pile and ignited as rubbish.
So what, exactly, is burning?
It’s time to find out.
Environmental scientists say it’s habitat for indigenous plants and animals -- habitat in one of the most biodiverse areas along the east coast of the United States.
In each episode of our new series called In The Wild Coastal Plain, we’ll meet a plant or animal and learn about it: how it lives, what it eats, what we know of its role in the ecosystem, and we’ll find out why our guide, Andy Wood, considers each single species as important as a rivet in the International Space Station. You’ll hear more about that later.
Longtime WHQR listeners will remember Andy Wood and his popular commentaries on local wildlife that launched in 1987. He’s compiled the most memorable pieces into a book entitled Backyard Carolina: Two Decades of Public Radio Commentary. But he continued for almost a third decade – until 2015.
He now directs the Coastal Plain Conservation Group, a nonprofit dedicated to just that: conserving what’s left of the coastal plain in southeastern North Carolina.
Links / Resources:
Andy Wood, Director, Coastal Plain Conservation Group
In the Wild Coastal Plain:Beavers, a keystone species
In the Wild Coastal Plain: Red-cockaded woodpecker and longleaf pine
Backyard Carolina: Two Decades of Public Radio Commentary by Andy Wood
In the Wild Coastal Plain with Beavers
[Sounds of water]
ANDY WOOD: Our abundant food supply is due in large thanks to the American beaver.
Rachel Lewis Hilburn: You thought it was bees? So did I. And bees are hugely important, no question, but beavers are right up there with them – considered a keystone species. We’ll get to the why of that soon.
I’m Rachel Lewis Hilburn and this is our first episode of In the Wild Coastal Plain – SE NC. That SE NC is, of course, southeastern North Carolina.
Our guide today is Andy Wood. He moved to North Carolina in 1982 to direct a summer science camp for the state’s Museum of Natural Sciences in Raleigh. Three years later, he followed his wife to Wilmington.
More than a quarter of a century after that, in 2012, he founded Coastal Plain Conservation Group, with his son, Biologist Carson Wood. Andy is the Director.
[TROMPING THROUGH THE BUSH]
ANDY WOOD: Part of the reason I asked you to wear boots is this has one of the highest densities of cottonmouths that I’ve seen anywhere –
RLH: Oh! Now you tell me…
AW: So, yeah, closed shoes and long pants are required and there’s one that actually lives right here. Last summer I’d see him or her essentially every day.
RLH: He calls them his “friends without shoulders.” We might investigate the role cottonmouths, a venomous water snake, play in the ecosystem in another episode. But I’m happy to start with our furry aquatic friend, and a mammal, the American Beaver.
And I suppose a very brief explanation of what we’re starting in the first place – and why we’re starting this – might be helpful.
North Carolina has a fast-growing population, although it’s not in the top ten as of 2023. However, Brunswick County, which is one of about five counties in North Carolina’s Coastal Plain, is also one of the top ten fastest-growing counties in the country.
Nearby New Hanover and Pender Counties are also seeing rapid growth rates.
And so we watch the elimination of great swaths of natural areas, home to a wildly biodiverse ecosystem.
Through this series, in each episode, we’ll meet a different member of the ecosystem, an animal or a plant species, what our guide, Andy Wood, calls the rivets in the space station, and we’ll try to understand how all of these members fit together to create a biodiversity hotspot known as the coastal plain ecosystem.
And so we begin with the American beaver.
If you’ve never seen one, we’re talking about adult beavers that can weigh between 35 and 60 pounds. Their coats range in color from chestnut brown to black in North Carolina.
They have short front limbs – Andy Wood says they’re actually arms -- and they have webbed hind feet. The state’s Wildlife Resources Commission describes a double claw on the second toe of the hind foot that the beaver uses to comb her fur.
It’s pretty easy to distinguish a beaver from a muskrat; look at the tail. The beaver has a long, wide, flat tail that it uses to store fat, communicate, and swim.
[SOUND OF BEAVER TAIL SMACKING THE WATER]
Yes, that’s what it sounds like.
The muskrat’s tail looks like, well, a typical rat tail.
What about the otter? They’re much smaller than beavers. And they have a tail that starts out thick but tapers to a point. They’re also active during the day and beavers are largely nocturnal.
[BIRD SOUNDS – WALKING]
Today, Andy Wood is taking me through one of the few undeveloped tracts of land remaining in New Hanover County. He describes this patch of land as possibly the most biodiverse area left in the county.
AW: The way to think of species, in my mind, the way I think of species, is as rivets holding together the life support system that’s keeping us intact here on earth.
So, imagine the International Space Station and the astronauts that are up there, every day, they are looking at individual rivets and nuts and bolts that are holding together the space station and they understand and appreciate the value of each and every one of those rivets. And if one of them said, hey, you know, we don’t need this one here – really? You’re willing to lose that rivet in this space station?
And the way I view earth, as hokey as this may sound, we’re on a starship. Earth is a starship. We’re traveling through the Milky Way – circling a star, and the star is traveling through the Milky Way. The Milky Way is traveling through the universe.
And when you look at a plant or animal on earth, it is a rivet, holding together the life support system, you can call it an ecosystem, if you want, but the fact of the matter is, if we lose all of the plants – if we scraped earth clean down to just dirt and water, humans would be extinct.
We think we’re invincible. We’re not. We are wholly dependent on the pyramid of life, if you will, that is formed of plants and wildlife – not cattle and dogs – but plants and wildlife.
RLH: We see a snake. All three of us freeze: Andy, me, and a nonvenomous black racer.
AW: This is one of our most common snakes. And this one that we’re looking at right here is about 3 feet long, an adult, probably 4 or 5 years old, and you can see it’s a dull black and that’s because it’s just coming out of winter dormancy. They don’t truly hibernate here. It’s just not cold enough. But it’s kind of a dull black. You can see some greenish-brown blotches on its scales. That’s either a fungal or a bacterial infection that snakes get, especially in winter when it’s wet.
It will molt. It will shed its outer skin, kind of like us changing our socks, and all of that will come off on the old skin. It will be a bright, shiny, jet-black snake chasing lizards, small birds, mostly rodents, other snakes, even frogs, they love leopard frogs. For lunch.
RLH: For lunch. Black racers are very fast – hence the name.
There are plenty of people who still say the only good snake is a dead snake. I ask what would happen if we lost the black racer. It’s a complex and possibly unanswerable question, but Andy takes a crack at it. And, in his quintessential Andy Wood way, winds up making an even more important point.
AW: If we lost the black racer, I would know it, and eventually you would be able to recognize changes in the ecosystem in the form of maybe there’s more rats. Maybe there’s more shrews – which wouldn’t necessarily be a bad thing -- but it makes things unbalanced, if you will -- not that there is ever balance on earth. There isn’t. There is no balance.
It’s totally out of whack, naturally, which is what has allowed evolution which is what has allowed beavers.
Change is the only constant on earth.
[SOUND UP OF LOADING UP THE BUGGY]
RLH: We’re about to visit a series of beaver ponds that are linked together ecologically – like a necklace. Andy drives us around in a very small all-terrain vehicle. He calls it a buggy. Locals, he tells me, call it a side-by-side.
AW: Let’s go find some beavers.
[buggy drives off]
AW: So we’re looking at a classic coastal plain stream. You can see the water is moving fairly slowly and notice that it’s a dark tea color – that’s tannin – the color is from natural pigments from plants – when you make a cup of coffee or a cup of tea, you’ll see the dark color coming into the water. That’s tannin.
RLH: The soil around the area is richly organic – like a giant teabag spread on the ground.
AW: When it rains the tannin leaches out of that organic matter into the surface waters, so it stains it this nice, rich color. It’s crystal clear but just stained.
RLH: It does look like strong tea.
AW: Yeah, yeah. Doesn’t taste very good.
[Sounds of the land – birds]
AW: This is an old ecosystem thousands of years old. As you see it today, if we were here six-thousand years ago this is how it would have looked.
RLH: It would have been cooler six-thousand years ago, says Andy, but we would be looking at the same community of flora.
AW: To a beaver that’s traveling around, messing around in this creek, it will decide – not maybe cognitively like you and I think, but the beaver will maybe be frustrated by the sound of that rushing water. It’s like tinnitus and it wants to get rid of it, so it will jam up some sticks there and maybe push some mud and go off an area – it may travel hundreds of feet away to get a bundle of aquatic plant matter, debris – and bring it back up here, cradling it in its front limbs, and tucked under its chin, and dutifully come and stuff it right there under one of the branches that it just stuffed into place, and it will create a little logjam, a little starting of a dam – just like me and kids have done for generations. Here’s a little rivulet; let’s go plug it up.
RLH: It’s the sound of the running water that tells the beaver where to plug up that stream.
[CREEK RUNNING WATER]
RLH: This particular creek is a tributary to a larger nearby creek, which is a tributary to the Northeast Cape Fear River, which is a tributary to the Cape Fear River, which discharges into the Atlantic Ocean.
AW: The beavers working in this stream will engineer essentially the whole length of the stream, and this has been engineered multiple times over the last thousands of years – going back to the Pleistocene – two and a half millions years ago -- beavers have been here, working.
Where we’re standing is in this little bit of a basin. We’re in the creek bottom, the drain, if you will, so when the beaver builds the dam, all of this is going to get flooded.
RLH: Many of the trees we’re looking at are wetland-adapted. We can see their roots sitting in the creek water.
AW: They’ll live for a time. The cypress will be just fine. But many of the other trees are going to drown and die. And this will be a pond and that’s why they will drown and die.
RLH: That sounds like a failure, right? It’s not good if trees are dying. But this is where it gets interesting – because this is how nature works.
AW: It will transition into another ecosystem, an aquatic ecosystem— that over hundreds of years, and beaver ponds last that long if the dam is intact, and what happens is silt and sediment coming down the stream accumulates in the bottom of pond and over many, many decades and even a couple of hundred years, the sediment decomposes on the bottom or the organic matter, building up to become –eventually this will become a meadow, and then it will become a forest, and then the stream will still be here—it’ll be carving through same area it always has and a new generation of beaver will be here in a couple of hundred years and say, well, what is the deal here? This noisy creek has just got to go. They’ll plug it up and this will become a pond again.
Much of North America’s best farmland is so good, especially in the breadbasket area, due to thousands of years of beavers damming little streams that formed into ponds that accumulated organic matter to make rich loamy soil that we grow our crops in.
Our abundant food supply is due in large thanks to the American beaver.
[SOUNDS OF THE ATV]
RLH: We’re leaving the creek and we’re heading now to one of the larger beaver ponds.
AW: So this is a beaver pond.
RLH: This looks otherworldly.
AW: It’s primordial.
RLH: It’s breathtaking. More than 30 years old, according to Andy. On this slightly overcast, warm, late-winter day, bare, gray-colored cypress trees reach out of the pond’s depths to the silvery-blue sky. Ghostly, they reflect on the pond’s still surface.
AW: All of that material – that’s also brought in by beavers.
RLH: He’s pointing to a patch of sticks and leaves and other types of debris about the size of a football. I would never have looked at this small pile and thought – oh, that’s beavers. But we have proof.
AW: So if you look, you’ll see… and there’s its paw prints.
RLH: Oh my goodness!! Beaver paw prints!!
[laughter]
AW: I’ve identified 13 species of fish, freshwater fish in this pond, which is fairly significant for a North American pond. And those are just the ones that I’ve caught.
RLH: What do beavers eat?
AW: They’re strict vegetarians.
RLH: When you look at a softwood tree, like a red maple, Andy tells me they harvest the maple and then sever the small stems. He looks around to find an example…
Picks up a branch
AW: This right here, that nice green material, that’s the cambium layer. So the beaver will cut this stem and imagine holding a corn cob in your hands and you chew off all the corn – that’s what the beaver is doing, eating the outermost bark – the thin bark – they don’t want to eat this coarse, rough, gnarly stuff. That’s the husk.
They want the nice lush, green cambium layer and they will peel that clean and it will be a white stem when they’re done and that’s their primary diet.
They eat some grasses. They’ll eat some of the other plant material.
But what they really want is hard chewable stuff because their incisors, their front teeth, are forever growing, along with their molars. So if you have a beaver in captivity and all you feed it is apples and carrots, their incisors will grow to the point where they may bite right through their lower jaw with their upper incisor. Just like a rat. They’re a big rat.
RLH: In fact, they’re the largest rodent in North America.
AW: And they live as a tight-knit family unit – mother and father, kits that stay with them, help build the dam.
Eventually, the young will get pushed out so there’s no hanky-panky. They get pushed out of the family and go find a place to build for themselves but otherwise they live as a family unit with the parents directing various activities – reinforcing the dam, maybe reinforcing the lodge, just being beavers.
And then eating. They eat and eat and eat.
RLH: Which is why they’re on a do-not-like list for timber owners.
And in some of these residential developments, it’s common for developers to get rid of beaver dams – even when they occur in natural areas – areas deliberately left natural amid the development.
In North Carolina, beavers are regulated by the state’s Wildlife Resources Commission.
AW: And it is illegal to transport beaver – you can’t take beaver from this pond and release them somewhere else. They have to be euthanized. They have to be killed, if you’re going to get rid of the beavers.
You can blow up the dam – literally they do with dynamite, the dams are that big – so they’ll blow them up or in some way disable the dam.
If it’s suitable habitat the beavers are going to come back. Some other beavers are going to come back.
At one time, estimates varied, but we think there were some 40 million beavers in North America before European settlement.
That number is way down now. I don’t know what it is.
They are removing beaver dams to basically remove backed up water.
RLH: Around the turn of the 20th century, beavers were on the verge of extinction. Hunters sought their pelts for coats, hats, muffs, collars, and other kinds of trim. According to the NC Wildlife Resources Commission, the population made a comeback by the 1950s.
There are actually efforts in the western part of the U.S. to restore natural beaver habitat. By removing the dams for other supposedly environmental reasons, scientists now see that humans caused more harm to the environment.
Is there any application of that idea to what we’re seeing in southeastern North Carolina?
AW: A wildly bizarre idea in many peoples’ minds – because the push right now is to remove dams to facilitate fish movement which I totally get -- but in doing that, when you’ve got an ever-expanding ocean in a coastal plain zone – and we are in the Atlantic coastal plain eco-region extending from basically Cape Cod [MA] to Mobile Bay, Alabama.
The ocean is now expanding – or rising a couple of millimeters a year – and that translates to meters of horizontal saltwater shift including upstream in these little creeks. And saltwater is wildly detrimental to freshwater ecosystems.
So what the beavers are doing for us is slowing the rate of saltwater intrusion into our coastal streams.
Look at Smith creek and the Lower Cape Fear – Town Creek -- all those dead cypress, those are sentinel trees telling us something is happening and that something is saltwater intrusion. Those aren’t just ghost trees.
Those are trees that have died as a consequence, primarily, of dredging the Cape Fear River which used to be 6-12 feet deep. It’s now almost 50 feet deep. And it’s the major river communicating directly with the Atlantic – so we’ve got lots of saltwater coming upstream.
RLH: Let’s just take that in for a moment. Beaver dams slow down the rate of saltwater intrusion in freshwater ecosystems.
And in the west, the efforts to remove beaver dams from streams to facilitate trout and salmon migration have created a new issue:
AW: With climate change, those now streams no longer have impoundments where cool water can remain and where water can collect and slowly percolate through the soil, recharging the aquifer.
So they started to recognize – wow, we’re losing aquifer water because our human endeavor is to move water off the land as quickly as possible, and that’s really not what nature has evolved these ecosystems to live with. These ecosystems want water to stay put for as long as possible, percolate slowly through the soil so that the water entering the aquifer is nice and clean.
RLH: So I’m starting to understand why beavers are a keystone species.
AW: Beavers are an ally for maintaining water quality, air quality, biodiversity, and flood protection, in that this pond will retain millions of gallons of stormwater for a period of time, slowly releasing it into the stream so that downstream homes won’t suddenly be awash with a flush of sudden water because much of that water has been contained, briefly anyway, in these beaver ponds.
From here to the Northeast Cape Fear River, I don’t know how many beaver ponds there are -- but it could be dozens.
Not all big.
This is a big one – this is like 12-15 acres. Others are just a couple of acres supporting just a couple of beavers. They’ve got their little cabin in the woods. It’s a wet cabin but that’s their lodge.
RLH: Remember Andy’s earlier analogy about the rivets on the International Space Station? How each one helps to keep the whole system in place?
AW: That’s biodiversity. The greater the biodiversity of an ecosystem, the more stable it’s going to be. Still not in balance but it’ll be more stable.
If you remove lots of species, then, think cattle out in a field. That’s what you end up with. Just cattle eating grass – and even that grass isn’t enough. The cattle will eventually starve themselves out by over-exploiting the resource.
So biodiversity is a buffer against resource exploitation.
When you clear-cut 100 acres to build a subdivision, nothing is left. Every box turtle is gone. Everything is gone.
The way we’re doing it here right now. This is a new model.
If you look at Bald Head Island or Avenel in Porters Neck, and many other subdivisions, Pine Valley – so many subdivisions around here had it right 20-30 years ago. They left the trees. They worked around the trees.
But now the developers just come in, scrape the land clear corner to corner, and put down their subdivision and nothing remains.
RLH: Andy tells me it’s likely that this region was the most bio-diverse area anywhere on the Atlantic coastal plain north of Florida – specifically New Hanover, Pender, Brunswick, and Columbus Counties – all in southeastern North Carolina. But, he says, New Hanover County probably cannot make that claim anymore.
AW: When I moved here in ‘85 it was heaven for somebody like me. Every day was a new discovery. Every day. That’s the case out here.
RLH: He means the land we’re standing on right now. Land that is protected and private.
AW: There’s something new I find in and around this beaver habitat – either a new plant or a new animal I haven’t observed before.
[FIRING UP THE ATV AGAIN TO LEAVE]
RLH: If we were to completely eliminate the beavers in southeastern North Carolina what are some of the consequences that you could predict from that? I know there are unforeseen consequences we wouldn’t know about until they happened. But what do you know would happen?
AW: Factoring in our burgeoning human population, that is drawing greater amounts of water from the aquifer, one of the most poignant consequences of removing beavers will be reduced aquifer recharge. That’s one.
The other is diminished biodiversity and the other is diminished stormwater control. These ponds store millions, billions of gallons of stormwater, even if just briefly. It slows the stormwater moving through the system and that’s what you want.
RLH: That’s what you want. Not to mention being able to find little beaver paw prints in the sand… but that’s my own peculiarity.
Heartfelt thanks to our guide on this adventure, Andy Wood of Coastal Plain Conservation Group. Thanks also to the folks who allowed us to record on their land.
And thank you for listening. I’m Rachel Lewis Hilburn for CoastLine’s In the Wild Coastal Plain.
