
Vanishing Voices: Saving Our Hawaiian Forest Birds
Special | 28m 31sVideo has Closed Captions
Native Hawaiian Forest Birds face imminent extinction, but many could be saved.
Native Hawaiian forest birds face imminent extinction from non-native mosquitoes carrying lethal avian disease. This story follows the urgent push to reduce mosquito populations and safeguard these iconic species, highlighting innovative tools, fieldwork, and the people working to keep Hawaii's forests alive with song.
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Problems playing video? | Closed Captioning Feedback
Vanishing Voices: Saving Our Hawaiian Forest Birds is presented by your local public television station.

Vanishing Voices: Saving Our Hawaiian Forest Birds
Special | 28m 31sVideo has Closed Captions
Native Hawaiian forest birds face imminent extinction from non-native mosquitoes carrying lethal avian disease. This story follows the urgent push to reduce mosquito populations and safeguard these iconic species, highlighting innovative tools, fieldwork, and the people working to keep Hawaii's forests alive with song.
Problems playing video? | Closed Captioning Feedback
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[wind and ocean sounds] [pensive music] Hanna: Hawaii has suffered more extinctions than almost any place on the planet.
Chris: Hawaii has been called the extinction capital of the world.
Hanna: We've lost over 70% of our forest birds.
Chris: That almost leads you to feel like what's the point?
And I don't believe that.
These birds deserve to be here.
Extinction is not something that we're talking about dinosaurs, or something in our history.
Chris: This is happening right now.
But some of these species have been around for five million years.
Why am I here at the end?
I don't want to be here at the end.
I want them to keep going.
Officials are working to save native Hawaiian birds on the brink of extinction by targeting mosquitoes.
Cali: It all goes back to mosquitoes.
So what we really want to do is control mosquito populations So what would a mosquito- free Hawaii look like?
[music intensifies] [music resolves] Narrator: Some say that when the first Polynesians approached Hawaii, they could hear the islands before they could see them emerge on the horizon.
Sam: Birds existed in the Hawaiian Islands long before people.
The birds in Hawaiian thought, and in the chant of creation are in place even before the gods are.
Birds have been here as long as there's been Hawaii, several million years.
And people have only been here about a thousand years.
Chris: As new islands and new habitats appeared you get little explosions of species that evolved.
And all of that really allowed for this tremendous amount o diversification in these birds.
From one ancestor we got over 50 species of Hawaiian honeycreeper Those birds are mentioned in songs, in chants, and stories that are celebrated in hula.
Birds were the caretakers of some of the Hawaiian gods, and the fact that birds would care for these people just as people were supposed to care for birds, is a relationship that goes way back into the strongest and oldest stories in Hawaii.
Kawika: Birds and feathers were always very important to give religious and political, spiritual identity.
Sam: In the time of abundance the birds ' feathers were utilized to create these beautiful capes and helmets, and standards called kahili.
It was an amazing thing to see.
So the birds represented the kind of abundance that the leadership of the islands were responsible for keeping in balance.
So to wear the feathers was to indicate your connection to the universe of life around you in the islands.
Every person, every being has a specific spirit that's attuned to them and their mana, and feathers is what would protect one's mana and contain it.
Birds were the embodiment of your ancestors, and therefore they could tell you things.
The songs of birds, or the sudden appearance of a brightly colored bird could be taken as a sign of the presence of your ancestors.
Chris: Hawaii has so much unique habitats, people, and culture, and many of these birds play important roles in stories passed down through generations.
but not only that, they're just, only from here.
They're part of that Hawaii identity.
Announcer: For millions of years, the islands of Hawaii vibrated with the songs of native birds.
Then, between the third and tenth centuries, Polynesian explorers set eyes on these breathtaking islands and were greeted by a sight of unparalleled beauty.
They were the first humans to discover the majestic wonders and abundant life that thrived here.
Their arrival brought new predators and changes to the landscape, but they lived with profound respect for the land and its native birds for centuries.
At the end of the 1700s, Western colonizers arrived, and the situation rapidly deteriorated with the removal of forests to accommodate agriculture, ranching, and urban development.
This replaced the rich bird songs with the sounds of Western progress, leading to a decline in native bird populations.
in the 1800s, whaling ships introduced mosquitoes to Hawaii, ushering in a more sinister foe.
These mosquitoes quickly spread throughout Hawaiian landscapes and facilitated the rapid spread of bird diseases such as avian malaria.
A challenge that most native forest birds were ill-equipped to face.
This led to multiple extinctions, and only about a third of the native forest bird species survived.
The remaining few retreated to the cooler, mosquito-free highland areas.
As the vibrant sights and sounds of these birds began to fade, humans attempted to fill the void with non-native species, diluting Hawaii ' s unique ecology with that of other places.
In the 1900s, conservation victories, such as preserving the Hawaiian nene were dwarfed by waves of extinctions.
Now, as climate change warms the islands, rising temperatures enable mosquitoes to ascend to higher elevations, causing the last safe habitats to shrink.
So with the rapid decline of safe places to live, many of the few remaining species are now on the brink of a new wave of extinction.
The loss of those birds is something that isn't a historical thing, it's happening now.
When I started in 2010, if you were hiking on the boardwalk in Kokee, you still had a chance of seeing an akikiki.
And by the next year we couldn't see akikiki.
Sam: I myself have seen five or so birds that were present when I was younger that are longer with us.
Luka: The forests are silent now.
So we know that their populations just crashed.
Hana: We only have six native honeycreepers left on Maui.
Even the areas that we work in, it doesn't sound anything like did 18 years ago when I started.
The forest is a lot quieter and it ' s definitely disappearing Cali: We'd started to monitor them so we could begin to catch them and collect their eggs and move everything to human care.
We'd find it, and before we could do anything, the adults would have died and the eggs would be cold in the nest.
We just watched in real time, the species going extinct in the wild.
In 2023, the U.S.
Fish and Wildlife Service formally declared eight Hawaiian bird species as extinct.
Hawaii has been called the extinction capital of the world because we have had hundreds of our endemic native species go extinct in a relatively short period of time.
So we know that there were over 50 species of honeycreeper at one point throughout Hawaii.
Today there's only 17 remaining.
We just lost iiwi on Oahu and Molokai in the last couple of years.
We're seeing this extinction event as an ongoing thing.
This isn't something that happened sometime in the distant past.
This is happening right now.
Hanna: Birds in Hawaii are obviously only found in Hawaii and nowhere else in the world.
And our islands are very small.
So once we lose them, we lose them forever.
Knowing that their populations are crashing and am I going to be one of the last to see these birds and hear their calls?
I still remember the time I saw the last video of the Kauai o'o, and recognizing that no one would ever hear that again.
We would never know what it is like to have that bird fly through the forest again.
In all the research that we've done, it has all pointed to avian malaria.
Christa: If you look around almost any bird that you see is likely infected with avian malaria.
And so there's a large source population for mosquitoes to become infected.
And in turn, those mosquitoes are able to transmit malaria to uninfected individuals.
There were no mosquitoes in Hawaii until the early 1800s.
And so that was the first time that Hawaiian honeycreepers and other bird species had been exposed to mosquito-spread diseases in millions of years.
The reaso Hawaiian species are susceptible and often die when they get avian malaria infections is that they evolved in isolation of avian malaria.
Cali: We sampled the mosquitoes and the birds for avian malaria using PCR tests.
And we have watched the number of birds and mosquitoes testing positive for malaria go up.
So we know that avian malaria is expanding and mosquitoes are expanding.
More and more places around the world are seeing bigger mosquito problems.
It's a potent example of climate change.
Ulalia: What we are seeing is a significant acceleration of the warming of our islands, and therefore a significant reduction in the habitat that our forest birds have.
So as global temperatures warm, mosquitos are now able to survive and thrive at increasingly higher elevations.
Now, avian malaria is moving upslope and it' invading a lot of these habitats that were once refuges for the native birds.
Chris: For Kauai, for instance, where the birds have been, there's a big plateau.
The mosquitoes were held at a certain elevation just below that plateau.
In the last few years, climate change has allowed them to reach above that line, and there was no stopping them.
Sam: Kauai now sees mosquitoes from sea level to summit.
And that is not a safe place for birds anymore.
Hanna: And in the last five years or so the speed in which avian malaria is moving into these native forest bird habitats has really accelerated.
Chris: A little over ten years ago, we thought there were about 500 kiwikiu.
They were seen as one of the most endangered birds on Maui.
Those trends have continued.
When you watch that 500 become 150... become 100, you suddenly can see the end, and it becomes much more scary.
Hanna: After 10 years of kiwikiu research the only real thing we could do at that time was to put them into new habitat and hope that we would be able to basically expand the areas that they could survive in.
But unfortunately, there were no other forest areas that were avian malaria-free in these high-elevation areas that we could move kiwikiu to.
Christa: In 2012 one of our big projects was to reforest a part of the island in order to translocate kiwikiu to that side of the island.
Hanna: So we spent about a decade rebuilding a forest almost from scratch on leeward side of Mau in Nakula Natural Area Reserve.
We try not to like, break the tree while we're taking them out.
Kiwikiu in its current range uses this plant a lot.
Hanna: lots of partners hui ' ed together to fence, remove the ungulates and start planting trees over there and rebuild a forest.
[power tool revs up] And I think for the first, let's just do the first row.
- Alright, and that ends the row.
- Chris: Oh, ok.
Hanna: We decided that the forest was ready to sustain birds in 2019 and made a plan to move a combination of captive and wild individuals over to Nakula to see how they could do in this more mesic habitat.
Unfortunately, not that long after the birds had been translocated, almost all of them died and they were found to all be infected with avian malaria.
That was definitely a very hopeless time.
Once those birds died, you know, everybody asked us, okay, well, what's next?
Well, you know, what's the next step in recovering kiwikiu?
We didn't have one.
You know, that was it.
We... we needed to build a habitat.
We'd been putting everything towards translocating these birds for the past 20 years.
And so when that failed, we really weren't sure what the next step was going to be.
You know, some of these birds died in people's hands.
Chris: Watching some of those individuals die, birds that I helped catch, it has not been something that I have gotten over very easily.
I really underestimated the impact that might have on me.
Because you see a bird, you have a little moment of connection.
When you capture that bird, now they have a name, essentially.
They have a face, and you become much more acutely aware that a species is made up of individuals.
They're not numbers, they're not a dot on a graph.
And that has been challenging emotionally.
Although there's a lot of hope, it's also, difficult to deal with the realities of dealing with some of these species that have so few individuals left.
Even though those birds died and that project was, was really hard to come back from, it really made the avian malaria crisis very tangible for everybody.
Everybody had been following this project, had really high hopes for Nakula, and to see how fast avian malaria could move into that area and also how fast it could just wipe out all the birds that we were translocating was really shocking to a lot of people.
In the last couple of decades, as the warming temperatures have allowed mosquitoes to invade the remaining akikiki habitat, has taken that population from several thousand birds to fewer than ten in the wild today because of mosquito-borne diseases.
So meanwhile, in 2015 we began collecting eggs to create an insurance population of the species in human care, while we try to address this mosquito crisis in the wild.
My staff, who are out there day in, day out, getting to know these birds individually.
They are seeing friends disappear, and that's been really rough.
There's this one bird named Pakele, and even though all the other birds from that field site are gone, she is somehow magically hanging in there.
And she built six nests last season while all the other birds around her were disappearing.
And she kept going.
To us, she single-handedly is trying to save the species in the wild and she's still there.
Somehow she represents what hope there is still in this situation.
When I was a kid, my mother would read to me that book, " The Little Engine That Could".
She is that little blue engine.
I think I can, I think I can.
She just keeps trying.
So she's a little tiny bird trying to do the job.
And I just, I cannot give up while Pakele is not giving up.
Our risks of not doing anything, is our loss of our birds.
And so if we don't do something now, we won't be able to do something in the future to correct that error.
Chris: In conservation, you kind of get used to fighting against declining trends.
But when you're looking at zero, that's when it really hits home and that makes it much more real.
We've definitely caused all these problems.
And especially when you see individual birds that are affected by disease in the forest and they are dying in the forest, it's like we owe it to them to fix this.
Hawaiian birds are part of Hawaii.
I mean, they are Hawaii essentially.
And when you lose them, you lose that which makes Hawaii, Hawaii.
So we have this shared responsibility to each other and we have this shared responsibility to our island home, which will ensure that we can all thrive for future generations.
Our focus right now is mosquito control.
Hanna: We can keep doing all the other things to help these birds.
But if we're not controlling malaria, they're going to disappear anyways.
If there was something that we could go out and get all of the mosquitoes in one go, I think we would definitely do that.
Chris: Humans have been fighting mosquitoes for centuries, millennia even.
And the only ways that we have really had victories is through major landscape-scale habitat change.
Draining entire swamps.
You know, there are whole ecosystems in North America that no longer exist because they were drained.
That's why we don't have malaria in the United States.
That in addition to wide-scale distribution of toxicants, specifically DDT.
Christa: We aren't going to use that here in Hawaii because we have an incredible diversity of native arthropods.
We would be killing all kinds of things that we want to protect.
So that's not an option that we could live with.
Starting actually in the early 1920s, they were looking into different forms of mosquito control and they noticed a intercellular bacteria inside this mosquito.
Chris: It was first discovered in the species of mosquito that we're trying to control here.
It's called Wolbachia.
Narrator: There is a cool bit of science that could save Hawaii's birds from mosquitoes called the Incompatible Insect technique, or I.I.T.
for short.
Imagine in Hawaii, mosquitoes have tiny puzzle pieces inside them called Wolbachia bacteria that exist in the reproductive organs of these mosquitoes.
And a male and a female mosquito need matching puzzle pieces to make baby mosquitoes.
So scientists do something super smart.
They raise male mosquitoes with a different puzzle piece or a different Wolbachia strain, separate them from females, and then let them loose in the forests.
The male mosquitoes can't bite and don't stay around long, but they have an important job, to mate with female mosquitoes.
They are released in such large numbers that the wild male mosquitoes are overwhelmed.
When these special males and wild females try to make baby mosquitoes, their puzzle pieces don't match and no babies are made.
It's a safe, clever way to reduce mosquito populations without hurting other animals or the environment.
And we know it's safe because various Wolbachia methods have been successfully protecting people from diseases carried by mosquitoes all around the world for decades.
And now in Hawaii, this tool is being used to keep native Hawaiian birds singing and our forests thriving.
Hanna: It is new for a conservation application.
So this is the first time that Wolbachia mosquitoes are being released for the benefit of forest birds rather than humans.
We're releasing male mosquitoes that don't bite and they don't transmit disease.
Chris: When you release just the males of your new laboratory mosquitoes, they go and find females or the females find them.
And then she lays eggs that never hatch.
And if you do that over a long period of time, then the mosquito population crashes.
The next part of it of course is how do you get those males out there?
And that's where some of the other fun comes in, because where we need this mosquito control to happen is extremely remote.
We don't hike into these places.
We fly in helicopters.
This is incredibly difficult terrain.
So, how do you disperse these mosquitoes in an even way across this forest that's super-vast?
So we breed our Wolbachia I.I.T.
males in a lab, and they ship us approximately 500,000 male mosquitoes, packaged into these little cardboard, completely biodegradable pods.
We then put those into a helicopter and we deploy them along a grid.
across sites in East Maui, native bird habitat, twice a week.
Right now, we're only able to control mosquitoes on about 3,000 acres.
And so as the project expands and we want to be able to cover more and more native habitat, that's just going to mean more helicopter flights, more mosquitoes, more time sprinkling these insects all over the landscape so that they have the opportunity to breed with the females in the wild.
This project is a partnership known as Birds, Not Mosquitoes.
And it is a group of both federal, state and nonprofit organizations working together to help protect the native forest birds from going extinct.
Hanna: It is a big project and it does sound pretty abstract and maybe... a little crazy to save little tiny forest birds, and there has been opposition to this project.
Chris: They have tried to prevent it from going forward.
An environmental group takes legal action against the state Land Department over plans to control Maui's mosquito population.
They don't want the state releasing millions of mosquitoes in an effort to save native Hawaiian birds.
It does sound kind of crazy, You know, we're going to breed millions of mosquitoes, and every week we're going to throw half a million mosquitoes out of a helicopter.
Maybe that is kind of hard for some people to swallow.
But if there was an easier way to do this, like we would be doing it.
There have been, countless brilliant minds that have been thinking very deeply about this malaria problem for a very long time.
And there are not a suite of tools on the table that we can choose from right now.
There is one tool, and we are trying to adapt that tool to make it work.
While in the meantime, there's also lots of other research and development trying to give us more tools to use in the future.
Wolbachia I.I.T.
has been used for decades all over the world, and we know that it's safe.
So we'll know if it's working because we've set up traps.
And we anticipate seeing a reduction in the mosquito populations in those areas.
Our biggest challenge is going to be can we implement it on a big enough scale?
Can we really do this at a large enough landscape-level scale to save all the species that we have left?
The only thing more tragic than losing these species is to have lost them and done nothing to try to prevent it.
I am completely terrified of having Hawaiian forests devoid of Hawaiian forest birds.
That is the consequence we at all costs need to avoid.
A lot of us conservationists, we deal with a lot of gloom and doom.
But if I didn't believe it was possible to turn this around I would be doing something else.
I have to believe that it's possible to change this.
As long as we don't give up, we can turn things around.
The mosquito control is so hopeful because it feels like such a big, bold new thing.
Combating the problem that we've known was there the whole time, but didn't have ability to fight it.
The vision is that you walk out of your door in Hawaii Nei and you see a native forest bird.
You don't have to go up to the Alakai.
You enjoy forest birds from your door because we have controlled all these threats.
Hawaii before pests like ants and cockroaches and centipedes and mosquitoes was truly a paradise.
Not only that the birds are thriving and are occupying the forests that they belong in, but that life in the islands would be that much closer to the paradise that it once was.
Mosquito-free Hawaii to me means by reducing something that brings me annoyance can also help be that hope to keep these birds here, so that they don't disappear.
Having their chorus be filling the soundscape of Hawaii again.
Christa: I want to have that cacophony of birdsong in my backyard that the first Hawaiians once heard when they approached Hawaii.
I'd like to see the honeycreeper as much as we see pigeons and myna birds around here.
If we were able to eliminate all mosquitoes, I think it would be safer for humans and a lot of other species as well.
I would love that to happen.
Because, if mosquitoes are gone, these honeycreepers can come down from the mountains.
I'd feel happy because the honeycreepers would be able to fly safe.
Griffin: Saving the honeycreepers is really a matter of saving the culture of Hawaii and the humanity of Hawaii.
if we can bring back these species from the brink of extinction that gives hope, not just for the species but it also means that we have the potential to do so much other conservation work here in Hawaii and around the world.
Seeing the joy that hearing what an iiwi sounds like to second graders, that brings me hope.
The iiwi kind of says its own name.
[making bird sounds] eee-eee-wi They would probably just leave out the W [making bird sounds] eee-eee [making bird sounds] eee-eee-wi [making bird sounds] eee-eee [chuckle] [making bird sounds] eee-eee-wi Kind of like that.
Luka: Also our younger generation at second grade are taking it up, We're here to talk to you about help for our honeycreepers.
they're going to the legislature talking in front of our representatives Thank you for your consideration.
Mahalo!
If we all do our little part in our own little space, those all kind of come together as a whole.
If we ignore that and just say, oh somebody else is going to do it, if we think of it that way, we're never going to help.
As our kupuna always taught it, we always leave someplace better than when we arrived.
I think that applies!
Beyond that extinction capital of the world, I would hope that we could be known as the capital that rises to that challenge and that brings full expression of our value of malama.
Can we be a place that we are known for the way in which we care for our homeland?
So maybe we are the malama capital of the world.
Avian malaria and the loss of Hawaiian forest birds and the loss of birds on Maui is just one of the bigger things that are in our total global disasters that are facing us.
But what we're doing here can save that species, or turn around the health of our forests.
And that is very tangible.
I can't solve climate change on a global scale.
But the things that we do here have a huge impact on the species that we're working on.
And it really is in our hands to either succeed or fail.
It means if we can succeed, then we have those species left.
For better or worse, that might be a lot of pressure, but people couldn't do it if they didn't care though.
I mean, I have these amazing teams of people, just working so hard, and I mean risking their lives on a daily basis to try to save birds.
And some people might think that's really crazy, but they also truly believe they're doing it to make Hawaii and Maui and the world and everything, a place that the rest of us want to live and have a future for.
We really want these birds to be there for our children.

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