- Just ahead on "This American Land," the mesmerizing sound of a ruffed grouse.

Scientists, foresters, and wildlife managers in Appalachia are working to restore this game bird's population.

- It's a story of hope.

- Farmers are adapting to changes in their water and soil by discovering the many benefits of cover crops.

- Plants are amazing in their different powers and their abilities to be able to modify their environment.

- I got it.

I got this.

- Reeling in a success story for sustainability.

Red snapper are back in Gulf waters.

- We found out real quickly how much interest there was to watch raptors.

[screeching] - This bar's big screen is for the birds.

Cameras on the Mississippi River are focusing on raptors, ready for their close-ups.

So settle back in your comfy nest for the best in conservation stories.

[upbeat music] ♪ ♪ Funding for "This American Land" provided by The Walton Family Foundation, The Horner Family Fund, Roni and Jim Wilkins, Jr., Winchester, Virginia.

- Hello, and welcome to "This American Land."

I'm your host, Ed Arnett.

As a wildlife biologist, I know one way to tell the health of a forest is to see how many ruffed grouse are in it.

But habitat loss and disease have led to serious declines in their numbers across Central and Southern Appalachia.

The sounds of this iconic, chicken-like bird are universal to hunters and rural residents across North America.

We sent our team across four states to check out many efforts to stabilize ruffed grouse population.

Marsha Walton has our story.

- This is the sound of spring.

[grouse drumming] - This is a male in full display, so putting on his best show.

He's got the ruff up, which is where they get their name.

He's got that tail fanned out.

He's got that orange eye stripe really showing.

So this is a, come to me.

I am the man of the woods, and I'm-- I'm ready.

- Reina Tyl is a biologist with the Pennsylvania Game Commission.

She helped spearhead the Eastern Ruffed Grouse Conservation Plan, aimed at the birds' long-term recovery.

- So off in that direction, just as we were standing here, I heard a grouse drumming.

I actually felt it first.

It's a really low-frequency sound that they make with their wings.

They create an air vacuum by beating their wings back and forth so quickly that, as the air rushes back into that vacuum, it makes a low-frequency sound.

[grouse drumming] - There's nothing that can compare to being out with family and friends and your bird dogs and good cover.

Seeing all the work that you put in to those dogs, a dog that can handle rough grouse is a master of their craft.

My name is Ben Jones.

I'm President and CEO of the Ruffed Grouse Society and American Woodcock Society.

- In Pennsylvania, ruffed grouse have been on a long-term declining trend.

And so the loss of that sound over the decades has really-- I guess people feel like there's a little bit of a hole in their heart when they go out to the woods in the springtime and they're not hearing that like they used to.

- After generations of these quirky, ground-dwelling game birds dominating rural landscapes, grouse numbers have fallen dramatically across Appalachia.

In the late 1990s, scientists and wildlife managers launched the Appalachian Cooperative Grouse Research Project to find out why.

- I'm Dean Stauffer.

I'm a retired professor from Virginia Tech.

There was some concern that particularly late-season hunting was causing the decline in grouse populations.

We were able to set up an experiment, and that allowed us to compare survival of grouse with hunting and without hunting.

- In the summer, chasing the females, you're running up and down the mountains in the heat through really thick forest.

- Researchers in eight states captured more than 3,000 grouse and put radio collars on them to track their movements and answer questions about their ecology.

Pat Devers was a grad student at Virginia Tech.

- What kind of habitat, how old is the forest that they're-- they're nesting in, and then how successful those hens are, how many of them attempt to nest, how many eggs they lay.

- We found that late-season hunting is fine, and it's not going to affect the grouse populations.

- While some states have closed or limited grouse hunting seasons, the team determined that was not the reason for the birds' decline.

It was because female grouse were lacking consistent foods needed for reproduction.

[gentle music] - We're going past crane facilities here.

[crane trilling] We've got whooping cranes, sandhill cranes, white-naped cranes, and Manchurian cranes.

- You won't find ruffed grouse here, but you will find exotic species from around the world at the Smithsonian's National Zoo Conservation Biology Institute in Virginia.

It's a former military cavalry facility.

- It used to have 7,000 horses and mules here.

And the Smithsonian took it over and replaced all those horse pastures with endangered species.

It is a research station for conservation.

- Wildlife ecologist Bill McShea is a leading authority on oak trees and the fruits they produce, acorns.

- What's available to rough grouse, what's available to turkey, what's available to-- to all the wildlife that's in here.

I'm-- I'm obsessed with oak trees.

- For ruffed grouse and some other species, it's all about the acorns, providing enough nutrition for hens to lay eggs and produce healthy chicks.

- So we've got red oaks, and then this is a chestnut oak.

And the seed production is very variable.

It's one year, you have a lot of acorns.

The next year, you have no acorns whatsoever.

And that sort of variability changes the dynamics of the wildlife populations in this place.

There are something on the order of 65 species that depend on acorns, of which grouse are one of them.

And that variability in the acorn crop rules the populations of those animals.

They go up when there's a lot of acorns, and they don't survive the winter well when there's no acorns.

- You know, West Nile virus, it's been detected in something like over 300 different species of birds.

- Veterinarian Melanie Kunkel works with fish and wildlife agencies in the Northeast on disease threats.

First discovered in the U.S. in 1999, the West Nile virus is their top disease concern for ruffed grouse.

- In populations that are already experiencing habitat loss, already may be struggling due to some of these other stressors, West Nile virus, if it comes in, it can threaten these populations more, versus in regions where you might have stronger grouse populations due to more abundant habitat.

- Kunkel has studied the prevalence of West Nile virus in grouse populations from blood samples provided by hunters.

- A lot of the state fish and wildlife agencies wouldn't be able to do the work we are doing today to protect not only ruffed grouse populations, but also other wildlife populations, without the-- the volunteer time and the willingness of hunters to work with us.

- Across Appalachia, grouse need young forests to thrive, 5 to 20-year-old plants and trees that have regenerated after a fire, windstorm, or timber harvest.

- This is what you have immediately following a clear-cut or another type of harvest.

Then, very quickly, after about one growing season, this is what you'll start to see.

This is spring green-up.

You can already see lots of seedlings coming in.

There's a huge range of songbirds that benefit from young forest.

You've got some species-- golden-winged warbler, redstarts, hooded warblers-- that they will nest in that young forest habitat.

And that is critical for them for that part of their life cycle.

- It takes active forest management, prescribed fires, and timber harvests to create a mosaic of forest age and species.

It's a difficult and complex conservation challenge.

- So we're here in the Ridge and Valley region of South Central Pennsylvania, north of Harrisburg.

And we're on one of our state game lands where we've done significant habitat work for ruffed grouse.

So this stand that we're near here received an overstory removal, which basically means we took the mature canopy, overstory trees, and removed them so that the young forest could regenerate in its place.

- Ruffed grouse may live their whole lives in less than 100 acres.

So their survival is all about their habitat-- ideally, a mix of young forests that provide protection from predators, nesting cover, and brooding cover for their chicks, as well as older forests that provide those all-important acorns.

- The story of ruffed grouse is a story of resilience.

It's a story of hope.

And it's a story of pragmatic, true conservation, that, if we do this work, we can conserve this species.

♪ ♪ - Change in nature can happen quickly in some cases, with obvious outcomes we can't miss.

Wildfires are a good example.

But sometimes it's gradual and barely perceptible to the human eye.

Unfortunately for some farmers, the changes underfoot can occur without them noticing until it's too late.

Soil and water quality are constantly under attack by the elements, sun, wind, and storms.

Our Brad Hicks shows us why more and more farmers in America are discovering the benefits of running for cover.

[chain clangs] - I'm Lillie Beringer, a third-generation farmer here in Cascade, Iowa.

- The cutting edge-- - So I actually have been out on the farm since I could walk.

- --is Lillie Beringer's comfort zone.

- At 24 years old, I purchased my grandparents' home farm.

- Like any farmer, she faces challenges.

- The cash flow is hard at that age.

- And she answers them with innovation.

- We have our little farm logo on it.

- But out in the fields-- - Hi, babies.

- --she's facing another problem.

And how she solves it-- - It's something we've never done before.

- --could impact fishermen 1,000 miles away.

♪ ♪ - The nitrogen that is leaching out of corn once the corn is harvested, if the corn didn't use all of the fertilizer, is going to waterways down the Mississippi basin into the Gulf of Mexico and ruining those fisheries.

- Lisa Kissing Kucek is a USDA plant breeder in Wisconsin.

- It's a full 6,000 acres of research land here.

- She's trying to protect waterways and groundwater by breeding better cover crops.

Cover crops, unlike cash crops, are planted primarily for their ecological instead of economic benefit.

- Cover crops have this power of being able to improve water quality by reducing the amount of fertilizers and pesticides that are used on agricultural land, and simultaneously saving growers costs of these inputs.

- This rye, for example, will grab excess fertilizer and nitrogen left in the soil from the last cash crop and turn it into nutrients for next season's cash crop.

- So it goes beyond the farm field.

It really does impact everyone.

- She's also working on the flip side of that ecological coin.

- These are the best of the best.

- Plants that will put nitrogen fertilizer back into the soil to replenish it naturally, like this unusual legume, hairy vetch.

- Legumes have the power of working with microbes in their root system to take nitrogen from the atmosphere and turn it into fertilizer.

So it's our goal, is to make a biological fertilizer for growers.

- Cover crops can perform a lot of different functions on the farm.

Most were originally planted in fallow fields to prevent bare soil from eroding.

- Come on, cows!

Come on!

- When the corn and beans come off Kent McClurg's farm in Western Wisconsin, he now plants cover crops for his cows.

- Probably some red clover and some other clover.

- The cover crops give his cows extra nutrition and additional grazing time in the late fall.

Well, they seem to be enjoying it.

- They-- they certainly love it.

- But what he loves is what the cover crops do for his soil.

- I want to keep that soil in place.

The top 1 to 2 inches of our soil is our most valuable.

You want that stuff to stay there, otherwise you're losing money.

- He has discovered the hidden benefit of cover crops.

While they aren't initially planted for making money, they can actually save farmers a lot in the long run because the benefits are buried beneath the surface.

- Plants are amazing in their different powers and their abilities to be able to modify their environments.

And farmers can be able to harness that power and have the cover crops do some of the work that they need to be successful in farming.

- For example, brassicas, the mustard, broccoli, radish family, they contain chemicals that work wonders.

- Those chemicals act as a natural fungicide.

So instead of having to apply a synthetic fungicide, farmers can use those cover crops to help draw down pathogenic fungi in their soil.

- And then there's rye, the king of the cover crops.

Cereal rye releases chemicals that keeps weeds from growing.

- It's a natural evolutionary trait, but farmers can use that to their advantage.

- And if the rye is crimped over like this when it's flowering, the cover crop does double duty.

- But this creates a lovely, thick mat that will suppress weeds.

- This is a natural herbicide.

- It is a natural herbicide.

It's a biological, ecological solution to manage weeds in a way that reduces and eliminates a reliance on chemical herbicides.

- Now I use cover crops.

I won't go back.

- Roger Bindl in Central Wisconsin is a huge fan.

- They work wonders for me.

- On this day, he's trying something new.

- It's an experiment.

- He's planting rye between his corn rows before the corn is harvested.

Are you a little nervous?

- A little bit.

But how will you know if you can get better if you don't try?

- The hope is, by planting early like this instead of when it's cold and the days are short, the rye will get a head start.

- And then, once the corn gets harvested in October, then they'll get-- the rye will get more light, sunlight and everything.

And then it'll just start growing like crazy.

- It's called interseeding.

- We are looking to actually demonstrate what we can do to better environment by keeping the farm viable.

- Greg Olson is the field projects director for the Sand County Foundation.

- Our name comes from the Aldo Leopold book, "A Sand County Almanac."

Aldo Leopold was the kind of, like, premier conservationist in the United States for many, many years.

And that's kind of what we follow, is Aldo Leopold's land ethic.

- Sand County Foundation makes funds available so farmers like Roger Bindl can experiment with interseeding.

Is this interseeding concept fairly new?

- It's been done for a few years now, but it still hasn't really taken off.

- Aircraft preparing to take off.

- That is about to change.

[energetic music] ♪ ♪ In Iowa, Sand County Foundation is covering the cost of interseeding in the Dubuque County watershed using drones.

They fly over the cash crop fields and spread the cover crop seeds.

So this could give farmers a reason to try cover crops.

- Yeah, this is our goal, was to get more producers into the program and trying cover crops for the first time.

- Which brings us back to Lillie Beringer.

- I'm all for it.

- Always eager to be on the cutting edge.

- It's going to be a trial-and-error type thing, but if they can fly it in earlier, it's going to be able to take off a lot better.

- And with live roots in the ground and crops covering the soil, her corner of Cascade, Iowa, will be keeping the Mississippi River a little bit cleaner.

[gentle music] ♪ ♪ - Decades of overfishing nearly wiped out populations of American red snapper.

But commercial and recreational fishing crews, conservation groups, and policymakers put their heads together a few years ago to find some answers in the Gulf waters.

Their actions led to more stable and sustainable populations.

Let's go to Galveston, Texas, and see how this conservation success story unfolded.

[pleasant music] ♪ ♪ - This is new technology.

This is a CLS America tablet that Bluetooths to the vessel monitoring system, the satellite system that the federal government uses to track the vessel.

I'm Captain Scott Hickman, a 30-year professional fisherman here in Galveston, Texas.

I do both charters and commercial fishing trips.

Galveston is a unique place.

It was the richest city in the United States before the Great storm in 1900.

It took years to come back.

It's basically become Houston's playground now.

It's home to the largest commercial fishing fleet west of the Mississippi River.

We've got Tom and Marty, our deckhand Hunter, the only female party boat captain in the Gulf of Mexico's son.

We've got my friend, Robert Jones.

- We're on a-- technically on a commercial fishing trip called a catch share experience.

And it's a really innovative hybrid.

Recreational anglers get the opportunity to come out and catch the fish themselves that then go back to the fish market.

And they can buy the fish directly from the fish market or not.

It's the ultimate sea-to-table experience.

- Oh, yeah.

- Man, that's a nice snapper right there.

- You got one yet, Justin?

Man, you keep talking about painting my boat yellow and taking people to school.

I see somebody else caught the first fish, Justin.

- Perfect size.

- Here in the Gulf, we've got three stakeholders that fish for these reef fish, especially red snappers, the most popular species.

We have a commercial fishery, which provides fish to the American consumer.

They have 51% of the yearly allocation of snapper.

We have the charter-for-hire sector, which takes the American that wants to come on vacation and get on a boat and go catch a fish recreationally.

And then we have the private recreational sector, which is folks that have their own boats, that live on the coast, that go out and catch their own fish on their own private boat.

♪ ♪ - The red snapper were overfished for more than 50 years and were on the brink of collapse just a decade ago.

- There's only so many fish out there.

There's only so many fish we can take out to sustain the population.

I hate to say it, but I was part of the problem.

I was one of the people out there throwing back dead fish all day long trying to get so many big ones.

- This is an undersized red snapper.

We're going to go ahead and throw him back so he can get bigger, and we'll hopefully catch him at some other time.

- In the old commercial system, in what we call a derby system, you're creating a race to fish, where people, they're incentivized to go out and catch as much as they can as fast as they can because they're trying to compete with the other guy.

And people go in and can wipe out a small reef in a 10-day season instead of spreading their effort out over the year.

- Who's driving the bus?

[laughter] - You are.

- I got tired of wasting a resource.

And that's what the status quo old system that we had did.

[gentle music] ♪ ♪ So catch share programs are where the allocation of fish is divided up amongst groups of people, individuals, or it could be communities.

It's market-based.

It's capitalistic but it's got a huge conservation benefit.

- Come on, Snappy.

- They tried it first in red snapper.

Pull up on that jig a little bit.

And within five years, six years, they were seeing huge increases in fish all over the Gulf.

I saw it as a charter boat captain.

Justin is not riding in the bus anymore.

He's driving it.

- Yeah, I already have four.

♪ ♪ - I kept telling myself, there's got to be a way that I can participate in this.

- I got it.

I got this.

- I built, basically, a hybrid.

- Yeah!

- Good job, Justin.

So I took a commercial catch share permit and quota and put it on my-- my once former charter boat and started taking people out for eco tours, eco experiences, to learn about the system and go out and harvest these fish.

- The shark ate my-- half my fish.

- This is maybe my second saltwater trip ever.

It sounds like a really amazing system, and this experience, in particular, has been really neat because we're fishing under, I guess, his commercial license and so that we are contributing to the commercial fishing.

But then I get the experience of getting to catch all these fish, which is so fun.

- Nice work.

[laughter] - Two.

Right here, right here, right here.

- I pay them with a good time and an education on that there's a different way to manage this fishery.

- People are gonna be in restaurants tonight eating fish that we caught here today.

Plus, we get to take a bunch of great fish home.

It's the perfect fishing experience.

- All right, you want to point the fish?

- Yeah, yeah.

- The underlying greatest thing about it is we've got a young man on the boat today that's 11 years old that wants to be a fisherman.

When he grows up, he'll be a fifth-generation operator in his family's fishing business.

[upbeat music] Every fish has got to get weighed.

We go upstairs, get on the government website before they can start cleaning anything, check those fish out of my fish account.

- How many pounds?

- 81 pounds.

- So those fish have now been deducted from the annual quota the whole Gulf-wide quota.

And they know up to date when those fish are being landed.

So there's zero risk of the fishery being overfished.

- I caught this fish.

Now I get to buy it.

- It's pretty awesome seeing your own fish come from right on the boat to the cutting board into this cooler.

Wow, that's fresh as it gets.

- Knowing that we're going to leave it off better than we found this fishery is a great legacy that we can leave this next generation.

There's not a lot of times that we get that opportunity in this country anymore, to leave things off better than we found it, and we're doing that.

[birds calling] ♪ ♪ - Time now to pull up a chair and enjoy a show with some feathered friends.

Some majestic raptors are getting rave reviews in classrooms and even some local pubs.

Brad Hicks goes along as a group of dedicated bird lovers sets up their latest camera on a cliff overlooking the Mississippi River.

- Fountain City, along the Mississippi River, sits at the midpoint between Green Bay Packers and Minnesota Vikings fans.

But at the Monarch Public House on Main Street, patrons are only watching the eagles and falcons.

- Now, who wants an old fashioned?

- The bar's big screen is reserved for birds, raptors being recorded on more than a dozen live cameras along the vital Mississippi Flyway.

- We've been eyeing this site.

- John Howe and his team at the Raptor Resource Project are about to make one of their cameras even better.

- Today, we're going to put a studio-quality microphone out there with the peregrine falcons.

- To do it, they need to rappel down a cliff.

The Raptor Resource Project began 35 years ago to help bring peregrine falcons back from near extinction along the river.

They set up cameras to monitor the nest boxes.

- We found out real quickly how much interest there was to watch raptors.

- With better technology and live streaming, the Raptor Resource Project cameras now give you a front row seat along the Mississippi Flyway, from Iowa to Minnesota.

Bald eagles and peregrine falcons are the most popular, but you can see all sorts of wildlife.

You never know who will make a cameo on the cams.

- It's just like you're sitting there living with those eagles or with those falcons.

- Back on the cliff, Amy Ries and Dave Kester are close to getting that new studio quality microphone installed.

[tool whirring] - What do you think about that?

- Snug as a bug.

It is going to be fantastic.

- Volunteers operate the rotating cameras on raptorresource.org.

Experts moderate live chat rooms.

Classrooms can even join.

And every few weeks, they compile a cleverly titled, binge-worthy highlight reel from the cameras you may have missed.

- We were calling them NestFlix, and somebody said, NestFlix and chill.

♪ ♪ - Now, here's a look at stories coming up in our next show.

- It's taken 40 years to fill the ocean up.

So it will take us a lot longer to find all these traps.

- Marine debris, traps, and nets, also known as ghost gear, threatening thousands of shorebirds.

- Thanks for watching, and we'll see you next time on "This American Land."

- And you can always watch our show on PBS Passport.

Funding for "This American Land" provided by The Walton Family Foundation, The Horner Family Fund, Roni and Jim Wilkins, Jr., Winchester, Virginia.

[upbeat music] ♪ ♪