Crowdsourced Data Identifies 126 ‘Lost’ Bird Species

16:16 minutes

Two birds sitting on a branch in a tree.
Two black-browed babblers. Credit: Panji Gusti Akbar

Some birds are famous for being extinct, like the Dodo and the passenger pigeon.

But how do we prevent species from reaching that point? One of the starting points is to try and track down the birds that are “lost to science.” These are birds that have not been documented in over a decade, but just might still be out there, if we look for them.

A new study analyzed data, images, and recordings from platforms that crowdsource observations from all over the world to identify birds “lost to science.” In total, the project, called The Search for Lost Birds identified 126 such species.

SciFri producer Kathleen Davis is joined by Dr. John Mittermeier, director of the Search for Lost Birds at the American Bird Conservancy to talk more about the findings of this research and what it’s like to track down a “lost” bird.

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Segment Guests

John Mittermeier

Dr. John Mittermeier is director of The Search for Lost Birds at the American Bird Conservancy.

Segment Transcript

JOHN DANKOSKY: This is Science Friday. I’m John Dankosky.

KATHLEEN DAVIS: And I’m Kathleen Davis. Some birds are famous for being extinct. Take the dodo, for example, or the passenger pigeon, but that is not a good thing. So how do we prevent species from reaching that point? One of the first things to do is try to track down the birds that are lost to science. These are birds that have not been documented in over a decade but just might still be out there if we look for them.

A new study tallies up birds that have been lost to science using data from citizen scientists all over the world. In total, the project, called the Search for Lost Birds, identified 126 such bird species.

So joining me now to talk more about this is my guest, Dr. John Mittermeier, director of the Search for Lost Birds at the American Bird Conservancy. He’s joining us now from Kampala, Uganda. John, welcome to Science Friday.

JOHN MITTERMEIER: Thanks, Kathleen. It’s great to be here.

KATHLEEN DAVIS: So walk me through what it means for a bird to be, quote, unquote, lost to science.

JOHN MITTERMEIER: So for us, lost means that there’s no independently verifiable documentation of the species in the last 10 or more years. So that’s photos, audio recordings, genetic material, any of that in the last 10 years. If there’s no records, then it counts as lost.

KATHLEEN DAVIS: OK, so how do you compile this list of lost birds?

JOHN MITTERMEIER: We just came out with this paper recently, and really the innovation of this paper was exposing and describing some of the methodology we use to build this list. And the way we did it was by crowdsourcing it with citizen scientists, scientists, ornithologists, conservationists around the world. And to start that process, we relied heavily on some of these big citizen-science platforms. Some of the listeners may be familiar with iNaturalist, eBird. Xeno-canto is another one. So these really impressive, huge databases with millions of photographs, millions of sound recordings, we started out with those as our first step to seeing whether or not a species had photos or sound recordings and, from there, reached out to experts around the world and narrowed it down to come up with this final list of 126 species with no documentation.

KATHLEEN DAVIS: So you’re in Uganda right now working with local birders and community members. Can you tell me about how local community members, what role that they play in locating lost birds?

JOHN MITTERMEIER: Two components to that. One is that when there’s more citizen scientists who are out there documenting species, they’re less likely to be lost. So one of the really important aspects of this project is collaborating with citizen scientists, trying to encourage more people to get out there and document birds in places like Uganda or even the United States or Canada, wherever anyone may be listening.

And then the other thing is that this project, as I said, is we’re using this definition of lost as no documentation that’s available to the scientific community. So in some cases, these species might not actually be lost to some people, right? There may be people living close to the species in the local community, or there may even be researchers, scientists in a specific region who have data about the species, but those knowledge networks just haven’t been connected.

So a big part of this project is about trying to reach out to people, share data, share information, get everyone on the same page, and, at the same time, find ways to build partnerships with citizen scientists and researchers who can help us document species that really don’t have any documentation.

KATHLEEN DAVIS: Yeah, so of these 126 birds, I mean, where in the world are you looking for them? Where are they located or were they previously located?

JOHN MITTERMEIER: So they’re located around the world, but there are definitely some clear geographic patterns. So one of the regions with the most lost birds is close to where I am now. Central Africa and, particularly, the eastern Democratic Republic of Congo has a number of birds that have not been recently documented.

Another region with a lot of species that meet this criteria are the islands north of Australia. So that’s Papua New Guinea and its surrounding islands. There’s a lot of lost birds there.

So you have these geographic clusters, but you also have species spread around the globe. For anyone in the United States, you might be familiar with the ivory-billed woodpecker. That’s a lost bird. That’s one of the species on our list. There are species in South America, the Caribbean, Asia. So they’re all over the place, but there are these hotspots of lost birds.

KATHLEEN DAVIS: Is there a reason that we can identify for why these clusters exist?

JOHN MITTERMEIER: Yes, I think there is, and one of the biggest reasons is lack of recent scientific fieldwork. Lack of attention from the scientific community is one aspect of it. Also, lack of connections between those knowledge networks that I mentioned before. So finding ways to connect with the people in those regions who might have that data, finding ways to foster citizen-science communities in those regions so that the people there can go out and find them.

I think, unsurprisingly, eastern Congo and those islands north of Australia are places where there are not as many people using platforms like iNaturalist. So, of course, there are fewer records that fit into our database there.

Often these are places that are currently harder to access or have historically been inaccessible for a variety of reasons, so there’s been less field work there. It’s often one of the things that leads to more lost birds in a particular area.

KATHLEEN DAVIS: Yeah. So let’s talk about a success story. So once you’ve identified a bird that’s been lost to science, you plan an expedition, see if you can locate it. And one of those trips, you successfully found a black-naped pheasant pigeon in Papua New Guinea. First of all, can you describe for our listeners what this bird looks like?

JOHN MITTERMEIER: For those of you thinking of pigeons, feral pigeons that you often see in cities, this is a totally different beast from that. So this is actually– imagine something more pheasant like. This is a large bird, pretty good size. It’s kind of glossy black with this bright, blood-red eye and bill and these sort of orange-brown wings. And it’s got this large fan-like tail that it pumps when it– pumps up and down when it walks.

KATHLEEN DAVIS: So how did you go about finding it?

JOHN MITTERMEIER: Yeah, so the black-naped pheasant pigeon, it’s known only from Papua New Guinea. It’s an endemic bird to that country. From a scientific perspective– this is going back to when we did this project in 2022. At that time, it was known only from three specimens, all of those collected in the late 19th century, and the most recent of those was 1896. So as scientists–


JOHN MITTERMEIER: –that’s very little to work with. Yeah, exactly. Not much data. But all of those specimens were from a single island, and the sort of understanding of this species is that it was endemic to that island.

So we started our project by visiting this island, wanted to go look for the bird. We used camera traps. This is a terrestrial bird, so we thought camera traps was going to be a good way to try to document it. But also one of the things that I mentioned to you, this is a large, charismatic species. There are a lot of people. The people living on this island were incredibly knowledgeable– are incredibly knowledgeable about birds and biodiversity. So our main strategy for looking for this species was reaching out to those people, conducting interviews, and asking them whether or not they had encountered it.

KATHLEEN DAVIS: So one thing that’s super interesting to me about this project is that you’re combining some really high-tech analyzation tools, but also you’ve got this very low-tech way of doing this science where you’re just on the ground asking people questions. So how did you eventually come to find that this bird was still living?

JOHN MITTERMEIER: That combination of high-tech and more low-tech methods is a good way of putting it, and that combo is exactly what led to this rediscovery for us. So we went around the island interviewing people, asking them if they’d seen this bird.

Surprisingly, many of the people we interviewed, despite knowing species on the island really well, said that they’d never seen this pheasant pigeon. They’ve never encountered it. They weren’t familiar with it. Until finally in one fairly far-flung, remote little community, we found someone who said, yeah, I know that bird. I’ve seen it, and I can take you to the exact spot where it is.

And so we went with him into the forest on his family land, and he showed us a couple of spots where he said, I saw this bird exactly here, and I saw this bird exactly there. And we set up camera traps at those locations. We also spent time walking around in the forest listening, looking, bird watching, seeing if we could spot this species.

We didn’t find it that way, but on our very last day, we ended up getting camera-trap photos of this species at exactly the spot where this local man had told us that he had seen it. So it was that combination of knowledge and people there on the spot telling us exactly where it was and then linking that with some camera traps and a more high-tech approach that led to success in that case.

KATHLEEN DAVIS: That’s so great. I mean, I would imagine that was just a huge sigh of relief for you and your team to be like, OK, this wasn’t all for nothing. We did actually find this bird.

JOHN MITTERMEIER: Absolutely. Excitement and relief were the emotions there. On the one hand, just this thrill. We’d been discussing amongst ourselves in the days prior to that photograph that we thought there was a less than 1% chance we were going to find the bird. I mean, we were already pondering how we were going to come back and think about our failure to find the species. So that absolute thrill of finding it at the very last moment combined with the relief of it having been– it was a very challenging project, in many ways, and to have it be finally successful was a wonderful feeling.

KATHLEEN DAVIS: So if you go through the trouble of going to a place, looking for a bird that’s lost to science, and you just cannot find it and you don’t get any leads, I mean, at what point do you say, this bird is just extinct?

JOHN MITTERMEIER: That’s a really hard question to answer because, on the one hand, you never want to give up hope. I just mentioned that story of the black-naped pheasant pigeon. That was over a hundred years with no records, and then we found it. It’s still there. There’s still hope for it. So you never want to say that something is absolutely gone.

But at the same time, it’s really important to try and get that information to really understand what’s happening to the planet and to understand what’s happening to these species. So it’s important to tell those stories of extinction.

The way we try and find that information is working on projects to really make sure that the locations where people go, that the effort that they use, the methods that they use are really carefully documented so that they can link with other projects and help us build a more comprehensive picture of whether or not a species is there. So you can sort of imagine a map of a potential distribution of a bird, and people are slowly surveying one area, surveying another area, surveying another area. And if you end up in a situation where all potential spots have been looked pretty carefully, have been looked exhaustively, then, in some cases, that can be the reason to say, well, I think we’re a little bit too late.

KATHLEEN DAVIS: And who actually makes that decision of if a bird is extinct?

JOHN MITTERMEIER: So that decision on extinctions and conservation status of birds is made by an international authority called the IUCN, the International Union of Conservation of Nature. And there’s something called the IUCN Red List, and they’re one of our partners in the Search for Lost Birds, specifically BirdLife International, which is the authority on birds for the IUCN Red List.

And so we work really closely with them to make sure that all our projects provide data that can directly feed into this Red List, that can help inform this decision of whether or not a species is extinct, whether or not it’s critically endangered, endangered, or whatever its conservation status is.

KATHLEEN DAVIS: What got you interested in leading this initiative to find lost birds?

JOHN MITTERMEIER: For me, this is really a lifelong passion. I started out birdwatching. I was always interested in nature as a kid, and I started out birdwatching around 12 years old. And not long after that, I have a very distinct memory. I managed to get my hands on a big, hefty textbook of threatened birds of the world, and I was flipping through it as any excited kid or enthusiastic bird watcher might do. And I came across this illustration of a bird called the Makira moorhen, which was this really cool and interesting-looking bird. And next to it was this distribution map with just a question mark.

And I was used to seeing all these other distribution maps of species with various shaded colors showing where they occurred and things like that, and just the idea that there was this big question mark on the map, that there was a bird that we didn’t really know where it was and we couldn’t find completely captured my imagination. And I knew from that moment that that was a bird I wanted to try, try and answer that question mark, address that. And then also it just really piqued my interest in this whole theme of these sort of mysterious lost birds, these species that are these puzzles, really, that are out there, but there are big pieces of their distribution, their life history, something about them that are still really mysterious to us.

KATHLEEN DAVIS: Have you gone out and tried to find the bird that you found in that book?

JOHN MITTERMEIER: I have. It took me a long time. I was quite young when I first saw it. I think it took about 15 years for me to manage to get the opportunity to go there. But yes, I have gone to look for it. I’ve actually been twice and spent a lot of time doing surveys and doing conservation work on that island. It’s called Makira in the eastern Solomon Islands.

And, unfortunately, it looks like we’re a little too late for that species. So, unfortunately, it’s probably extinct. But our work there has had some other really positive outcomes and some really positive collaborations, including helping some of the communities there develop a protected area and develop a system of sustainable carbon credits to benefit them in a sustainable way.

KATHLEEN DAVIS: Wonderful. So we have a lot of birders that listen to Science Friday, but a lot of them are located in North America. As we’ve discussed, many of these 126 birds are just around the world in many different places. How can listeners at home help with this effort? Can they?

JOHN MITTERMEIER: Absolutely. I’d say there are two ways where anyone can really help out. And as I mentioned at the start, we see this really as a global collaboration, and we want to try and get people involved, and any help is wonderful.

So two ways. One would be, check out our website. It’s searchforlostbirds.org. We have the list there. And if you happen to have any information on any of these species or you know someone who has information, please share it with us. Reach out. There’s opportunities to add information to the website.

So as I said, we did this global analysis of data, but there could be things we missed. So we’d really love to hear from anybody who has info, has up-to-date records of species that we didn’t get in this initial review.

And then the other thing is, as I said, we use citizen science to try and come up with this list. So we didn’t review them all manually because that would have been a lot, but we used some methods to review the greater than 40 million photos and audio recordings in these big citizen-science platforms, like eBird and iNaturalist that I mentioned before. And so if you’ve contributed photos or anything to any of these platforms, you’ve helped out, and that data is really valuable to conservationists and scientists. So please keep doing it. It’s really helpful, regardless of where it is we have.

KATHLEEN DAVIS: Well, that’s all the time we have for now. I’d like to thank my guest, Dr. John Mittermeier, director of the Search for Lost Birds at the American Bird Conservancy. He’s joining us from Kampala, Uganda. Thank you so much for joining us.

JOHN MITTERMEIER: Thanks, Kathleen.

KATHLEEN DAVIS: And if you want to read a complete list of birds lost to science and find out more about the project, go to sciencefriday.com/birds. That’s sciencefriday.com/birds.

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