How do you find a ‘lost’ species?

Species lost to science

0:00Hey, it's Kathleen Davis, and you're listening to Science Friday. We've known for a while that the Earth is facing a biodiversity crisis, with thousands of species on the brink of extinction each year. So biologists pay a lot of attention to those species that are endangered or threatened, and at risk of dying out completely. There's another critter category that's a little more mysterious, species that are lost to science. That means scientists aren't quite sure how many of them are out there, or if there are any left at all.

0:34My next guest is dedicated to finding more information about these lost species, so much so that he created a whole scientific journal about them. Dr. Matt Forrester is a professor of biology at the University of Nevada, Reno, and editor-in-chief of the Journal of Lost Species. Thanks for being here, Matt. Thanks. Great to be here. What does it mean for a species to be lost to science? Is there an official definition? There is. There's different definitions, and it's evolving. But the most common one is to say that a lost species is one that has not been recorded in the wild within the last 10 years, is not in captivity or propagation, and has not been declared extinct by the IUCN, the International Union for Conservation of Nature.

1:16OK. I'm thinking, does this definition get tricky for things that are maybe not quite in the public consciousness, like insects, like things that people might not just be looking for that often? Yeah, it's fascinating. The definition is both very straightforward, and it instantly gets tricky for the reason that you just suggested. There are so many, so many species, really most species, that no one is looking for most of the time. So it is the case that for a great number of species, we don't have a record of them in the wild within the last 10 years.

1:50But we would say they're still lost. If you don't know where something is, then it's lost. And we find that the designation of a lost species is motivating action and search effort and just sort of a different way to think about what we don't know as opposed to simply categorizing things as being deficient in information. So why do we need a specific journal that is focused on lost species? What's the benefit that this can provide? Yeah, it's a good question. On the one hand, we really think generally that we need to be doing a better job keeping track of the current biodiversity crisis, keeping an eye on species as they progress from becoming more rare towards extinction.

2:34Because if we can catch them in that trajectory, we can do something about it. Why do we need an academic journal? Well, an academic journal is really where scientists, you know, bring the receipts. It's where we go on the record saying something. So a journal is a place where we can float a new definition of lost species and other scientists can critique it and respond to it and it all is part of the record. But also the reason we want to have a journal is to leave a permanent record of species, especially if they end up becoming extinct.

3:06So we think memory is really important and we're not going to save all species, but we want to have we want to have that formal record so that we will remember. Okay, so more than 4,000 species are lost to science. What does that mean for our understanding of those ecosystems? Yeah, we often think that we're entering an era of extinction and we are, but before extinction comes extreme rarity and that's where the lost concept comes in. And when things are so rare that we don't know where they are, it's likely that they are not fulfilling the same roles in ecosystems that they used to fill.

3:41So that is a degradation of how nature works. It's also worth saying, and this is really a motivation for our journal too, is that we do believe that all species are worth keeping track of and remembering just because of their intrinsic value, not necessarily because of the roles they play in ecosystems, but all of that is important.

Searching for missing wildlife

4:02How do you go about finding a lost species? I mean, it sounds like it should involve a lot of detective work. Yeah, it's detective work and it's, in some ways it's a little old fashioned that way. On the one hand, there's the detective work of historical documents and museum records, which really relies on people going to museums and looking in drawers because most of our museum records globally are not digitized. So it's a physical effort of looking for historical specimens and then turning towards the wild.

4:34We actually need people going out and looking for plants and animals, which means it is really very much an expedition-based physical searching activity. How do you determine if a species is extinct or if it is lost to science? It typically takes the biological community decades to agree that a species is extinct. It will never be seen again. And as you probably know, there are famous cases of species that are almost certainly extinct within the last hundred years that we as humans just don't want to give up on.

5:10So sightings will continue to turn up, right? And we can definitively say something is lost right now if you can't tell me where it is in the wild. So that's very clear. It means we should go out and look for it. On the other hand, we need to wait decades to be sure something's extinct. So lost really fills an important gray area there in the meantime. Yeah, I mean, some lost species take on kind of a mythical quality. And I'm thinking of the Tasmanian tiger, which went extinct in the 30s. But people still claim that they see them today.

5:42I mean, how do we thread that needle of, you know, wanting these creatures to not be extinct without mythologizing them? Yeah, I don't know the answer to that. But I have to say, I kind of love that about humans, that we so desperately want, you know, that animal in that case to be out there, that sightings, I think, are just going to continue to turn up. And so there will be ambiguity over the extinction status. But there is no ambiguity that that animal is lost because no one has produced a record that we can all agree on, a verifiable photograph, etc.

6:17But it is an interesting aspect of this problem. Matt, before I let you go, you study butterflies. Are there any butterfly species lost to science that really tug at your heartstrings? Yeah, the one that comes to mind is the Sacramento Mountains checkerspot, which was actually, in many ways, the motivation for the journal. Two years ago, I was reading student grant applications, and I read a proposal that included mention of this butterfly that had not been seen in many years and which I had not heard of.

6:48And it's sad. It still has not been seen. I realized at that point that we really don't have a good venue for scientists to report on species that they can no longer find. And that butterfly is not alone, especially in the southwestern U.S., that is warming and drying because of a shifting climate. Well, Matt, thanks so much for coming to talk to us about this. Thanks for having me. It was great to talk to you. Dr. Matt Forrester is a professor of biology at the University of Nevada, Reno, and editor-in-chief of the Journal of Lost Species.

7:22After the break, we'll focus on a group of lost species who don't shy away from the limelight. They create it.

7:30Butterflies are not the only insects lost to science that researchers are hoping to find.

Tracking rare firefly species

7:47Enter the humble firefly. Of the 178 firefly species in the U.S. and Canada, 28 of them are currently lost to science, according to a community science project called the Firefly Atlas. Candice Fallon is a firefly researcher who's working to confirm which firefly butts are still blinking and which have burnt out. She's a senior endangered species conservation biologist at the Xerces Society for Invertebrate Conservation. Candice, welcome to Science Friday. Thanks for being here.

8:18Thanks for having me. Okay, Candice, you are a firefly detective, and correct me if I'm wrong on that. Do a lot of people have your job? Not that I'm aware of, no.

8:31There's a small group of folks studying fireflies in the U.S. and Canada, but not as many as you might think. I mean, how does looking for fireflies compare to looking for other insects? Because I think of them as a species that's, you know, you see them at night on like a very particular part of the summer. Does that make them harder to track? It does make them harder to track. You know, we have the lights, which are helpful, but really there are three different kinds of fireflies. And so there are daytime fireflies as well as glowworm fireflies.

9:03And each uses a different way of communicating, which can also make them, you know, more difficult to detect in some ways or another. I mean, daytime fireflies. Like, what is the benefit of being a firefly that is creating light during the day? Well, the daytime fireflies actually don't create light as adults, although the juvenile stages do. They use pheromones to communicate with one another and find mates. And some researchers actually think that the daytime fireflies used to be nighttime and they kind of evolved to move into a daytime activity period because of predatory fireflies that were actually eating them.

9:51I guess I didn't realize that fireflies were so diverse. They are. Yes. Yeah, a lot of people are surprised, first of all, just to hear that we have so many species in the U.S. and Canada. And then we have the glowworms, which are, I think, really interesting. The males in most species are non-luminescent. Instead, they have these really enormous eyes and they're flying around looking for flightless females that glow from the ground. And the females actually look more like grubs than your typical firefly.

10:22Interesting. Okay, let's talk about some of the lost firefly species that you're hoping to find. I hear you that you recently went on a hunt for the Nelson's Desert firefly. What is special about that firefly? I did. That firefly hasn't been seen since 2005, so over 20 years ago. And I was in Southern California doing some butterfly surveys and thought I would take the opportunity to look for it at its last known location, which is in one of the state parks down in Southern California.

10:55This firefly is interesting. It's been seen so rarely that we really don't know much about its life history. We're not even sure if it's a glowworm or a daytime species. So it definitely makes it harder to look for it. Basically, any time of day or night is open to possibility. Okay. But the males are the only ones that have been seen so far. They have these rosy heads and black wings. I think they're quite handsome looking.

11:25But yeah, it's definitely one of the lost species that we hope to find. And I was only out there for a couple days. It was a very short survey effort. But hopefully more folks can go out looking for it. I mean, going out to search for fireflies kind of sounds like a dream job. And maybe I'm just projecting because I have very fond memories of catching fireflies as a kid. But is it always a pleasant experience? It's often a pleasant experience. I would say it's a mixed experience. It's very exciting. And it is in many ways a dream job.

11:57I will admit that most nights that I go out looking for fireflies and find them, there are many squeals of glee. To have seen them. But that said, yeah, it's easy to romanticize fieldwork. But, you know, we still have all of the things to deal with that you would with a typical field day. So biting insects, maybe some spiky plants, long, hot days. Usually we're out in the middle of somewhere looking for, you know, fireflies when it's sometimes over 100 degrees.

12:31Oh, my gosh. And there's all sorts of other creatures around which can make things exciting. And, you know, often going off trail, often in areas with uneven footing, trying to keep our lights off so as not to bother the fireflies. So it can get pretty exciting. Does that mean that some of these firefly species just have like a very narrow condition for where they live? Yeah, a lot of habitat specialists. So they're only found in a certain place. Most fireflies, they have a very specific time of, you know, year that they're out and also time of night or day that they're out.

13:06And so that can really make some of these surveys more difficult because some species as adults may only be active for a couple of weeks each year. And even during that time period, they may only be active, say, you know, like 20 or 30 minutes at night. Only 20 to 30 minutes? Is that what you said? For some species, yes. That's bananas. Yeah. Others are active for longer, you know, an hour, two hours, three hours. Some of them will continue flashing all night long.

13:38But it really varies depending on the species. So you really just have to be in the right place at the right time, I think. Yes. I mean, have you had any success stories? Have you actually located any of these lost species? I have not. Well, I don't believe I have. There's one species that I looked for this summer that I may have found, but I still need it to be confirmed.

14:01Well, that's exciting. It is exciting. I'm not getting my hopes up yet because that species hasn't been seen in a while. But that's another, you know, difficult thing with some of these fireflies that are lost is that they are difficult to ID. And so, you know, it's possible that some of the sightings that folks have had of fireflies could represent some of these lost species. But we just need to get them confirmed by experts. What is the species that you think you may have found? It's a daytime species. It's called the granular necked firefly, which is not a great common name.

14:35Sure. And it's only known from, I believe, Oregon and Montana. And I went looking for it in Oregon, in Southern Oregon this summer.

14:45So, yes, TBD, if that has been found or not. All right. I'm crossing my fingers for you.

Community science and firefly atlas

14:51I mean, if people are listening to this and they're getting really excited about fireflies and they want to help find some lost species, is there a way for them to get involved? Yes, absolutely. So Xerxes started a community science project called the Firefly Atlas several years ago. And the whole goal of that project is to track threatened and data deficient fireflies across the U.S. and Canada. And, you know, we accept data for any species that occurs in the two countries. But we have a couple sub-projects.

15:24And one of those is for lost species of fireflies. And, you know, we highlight six species on the website that we hope folks will go out looking for, including the Nelson's Desert firefly. But really, we encourage people to go out looking for any of these species and reporting what they find. Yeah. And so just going and participating in that project would be super helpful. And reading up on these species, finding out, you know, where they were last seen, the time of year that they're active, and sharing what you find.

15:56Before I let you go, is there a favorite firefly fact that you have that would just blow my mind? Oh, no. Not to put you on the spot. A favorite firefly fact. I, you know, I don't know if I have a favorite firefly fact. I guess I will say I encourage you all to go looking at photos of larval fireflies because they are really bizarre looking and not anything like what you would expect.

16:28Describe it for me. You know, they are these armored larvae that are kind of flattened. And I've heard people refer to them as steamrolled roly polies or tiny pangolins or baby alligator larvae. Like, they're just really interesting looking. They have these fierce mouthparts that they use to, you know, go hunting for worms and snails and slugs. And they pierce them with these mouthparts and immobilize them and suck down their juices.

17:01They're really quite, well, they're probably quite terrifying if you're something that they're eating. I cannot think of a better place to end. Candice, thank you so much for being here. Thanks so much for having me. Candice Fallon is a senior endangered species conservation biologist at the Xerces Society for Infertebrate Conservation. This episode was produced by Shoshana Buxbaum. Before we go, we need your help. We are working on a story about the ocean and we want to hear your best sea stories.

17:31What's the most memorable or surprising thing that happened to you at the ocean? Did a snorkeling experience bring you to tears? Did you fall in love with sea slugs at a tidal pool? Did you lock eyes with a manta ray and realize the meaning of life? Tell us where you were, what happened, and why it was so important. Call us with your story. 877-4-CY-FRI is our number. Again, 877-4-CY-FRI. I'm Kathleen Davis. Catch you next time.