Feathers in Flight: The Bird Genoscape Project | National Geographic
We are on the Kern River Preserve. It's beautiful to walk on the preserve this time of year. The mornings are really cool. This time of year is also amazing because you're hearing all the bird song earlier in the morning. The willow flycatcher is this small plane bird [Music], and it flies around and catches flies because that's the type of insect it eats the most. It nests near rivers or creeks. [Music] [Applause] Knowing their vocalizations is key to doing the research because otherwise you'd rarely see them if you didn't. They say what the flycatchers do is fit spew. You wouldn't even call it a song really. I mean, it's okay; it doesn't sound bad. I love it when I hear it because that means there's a willow flycatcher nearby.
So definitely, I've lived here in the Kern River Valley since the winter of 1990. When I first started working here, there were more willow flycatchers, and now it's down to about, as far as we know at this point in time, one individual. That's all we know of right now, and it's kind of depressing. [Music] As a whole, Empidonax trailii, the willow flycatcher is not endangered. In fact, it's relatively abundant in North America. However, the subspecies that inhabits the southwestern United States is federally endangered because of rapid and steep population declines over the latter half of the 20th century.
Basically, I view the willow flycatcher as a canary in a coal mine. It's not doing well, so why is it not doing well here? If you can solve that for the willow flycatcher, it's probably going to prevent other bird species from having the same problems later on. In the U.S., there are roughly 100 species of neotropical migratory birds that are either threatened, endangered, or a species of special concern. A neotropical migrant is a bird that breeds in North America and then migrates south of the U.S. border into the neotropics.
Before I really began to study migration in detail, I tended to think of these birds as our birds. They're in the North American field guide; they must be North American birds, right? But they spend, in most cases, more than half the year south of the U.S. border. Of the nearly 800 species of birds that breed in North America, about half migrate into the neotropics. It's just a huge number. So if you observe that a migratory bird species is declining, one of the first questions you have to ask is whether it's declining due to factors on the breeding grounds in North America, the wintering grounds in the neotropics, or somewhere in between, or a combination of those.
[Music] The main reason why it's hard to figure out why some of these species are in trouble is because they're only in our backyards for say three months of the year. The rest of the time, we don't know where they're going, so we don't know what threats they're facing in those areas. In order to develop conservation strategies, we need to be able to identify how breeding and wintering populations are linked. So migratory bird conservation has to be a collaborative effort with biologists all over Latin America.
More than 220 species of birds actually migrate mostly from North America to Costa Rica. Birds know no borders; they don't understand these boundaries between countries. They simply use ecosystems. There are huge networks of people that do bird banding all over the Western Hemisphere. So you capture the birds in a mist net, and you put a little metal leg band on the bird, and then you hope to recapture that bird at some other point in its annual cycle. But the recapture rates are incredibly low; they're less than one percent.
So our thought was, well, if we could develop a technology that could use information within a single feather, like information in the DNA of the bird, to track the migratory movements, then we can take a feather collected from anywhere along the migratory journey and link it back to which breeding population it came from. The Bird Genoscape Project is an effort to use genomic sequencing to understand the population-specific movements of migratory birds. [Music] The original idea came from the co-director of the Bird Genoscape Project, Tom Smith, who literally just decided about 20 years before the technology was actually available that we should be able to do this.
In the early 90s, I naively thought that well, if we just collect some feathers, we'll be able to get DNA out of feathers, and it took the Human Genome Project to really develop the tools to enable us to begin to link populations. So I live in Colorado now, but if I wanted to know where my ancestors came from, I might send my DNA off to a genetic ancestry service. They would compare my DNA against this huge database of DNA from many, many other people and be able to identify that most of my ancestry is from Norway, which is where I know my grandparents came from.
We can do the same thing with the Bird Genoscape Project. We collaborate with these bird banding stations, which are all over North America and Latin America, to collect feathers. Then our first step is essentially creating that ancestry database. When we sequence the genome from birds all across the breeding range, we use that to build a map of how the different birds are related to one another and what the unique, genetically unique populations are across the breeding range. Then we can take a feather collected from outside of its breeding range, and we can compare that with the expected genetic profile of birds from different parts of the breeding range, and we can tell you that this bird is actually a bird that might be found breeding in the Sierra Nevada mountains or New York or something like that, which is really cool. [Music]
My specific role in the Bird Genoscape Project is collecting genetic samples of willow flycatchers throughout their wintering range and then also the breeding grounds as well. My role is the fun stuff, I think. [Music] I have a speaker, and I'm going to use it to do some playback of the willow flycatcher vocalizations in order to lure it into the net. I use a long cord, so I'm a good distance away from the net, and I won't scare them. Where'd it go? [Music] Yep, that's him! He was a feisty one, but we got him! [Music] So this is a willow flycatcher. He's not happy; he's a very feisty guy. [Music] There we go. [Music]
Okay, so the first thing I'm going to do is one of the most important things: to have the genetic samples. So I'm going to pluck the tail feather first. Sorry, guy. The general sort of description of where the willow flycatcher winters from bird books is from Mexico down to the northern tip of South America. When the southwestern willow flycatcher was listed as endangered, we had no idea where this particular subspecies wintered. Did it go throughout that whole range or just a portion of the range? We had no idea.
Once we have developed what we call the Genoscape, the map of how populations are related on the breeding grounds, we can take any individual captured on the wintering areas or anywhere along its migratory trajectory and tell you where that bird was from. So the end product of the Bird Genoscape Project for a particular species is the creation of a map that details the genetically distinct lineages and where they're found on the breeding range, similar to the kind of map that you would find in a bird book, but in this case, it's population-specific. It also details where those different populations, which migratory routes they use, and then where they're found on the wintering grounds.
The Virginia escape project was able to show us with high precision where the wintering areas of the southwestern willow flycatcher are. So people have dedicated their lives to knowing where this bird spends the winter, and we know now that it winters in specific areas in Costa Rica and Nicaragua. So now we can really focus our efforts to where they're needed, which is super cool. That's the whole point. Right now, we have just for the neotropical migrants about 200,000 feathers, so that represents roughly around 100 or so species. Right now, we're working on roughly 20 species of migratory birds, and they're in various stages of development.
Our long-term goal is to map 100 species of migratory birds of higher conservation concern by the year 2025. The collaboration is growing. If we go back to the early 90s, it was myself and my graduate students in my lab, and now, you know, we have many, many collaborators from across North America and Central America. We know where the birds are and where to get the samples. What we're doing right now is just adding one extra fuel, which is collect the feather and send it back to the States for us. That's very little, but for the birds, that's huge, and that's our win-win relationship with the Bird Genoscape Project.
The ultimate goal is really creating a network, a franchise if you will, of different universities, different research groups, all coming together to solve these mysteries of migratory birds. That's my hope. I think the willow flycatcher is a fantastic example of why the work is so important. It enables conservation to be targeted to those places in most need. If the southwestern willow flycatcher went extinct, I think a lot of people would shrug their shoulders and say, well, that doesn't, you know, matter a whole lot. But I think the decline of the southwestern willow flycatcher is kind of an alarm call. If it disappears, it's a huge warning that there's something wrong.
[Music] [Music] I think birds bring people together. It is like when you go to another country, and you realize that someone speaks the same language and you can have endless conversations just because you speak the same language. For us, it's the language of bird conservation. [Music] I think one of the great outcomes of the project is connecting the people who are working on the same birds but in different parts of the world at different seasons, in a way that couldn't happen before, because we didn't know where the birds were going.
That makes me really happy. It's the same birds in your backyard in Guatemala that are in my backyard in Colorado. We're all sort of working toward the same goal with the same species, and it's just, it couldn't be more clear that we all need to be on the same page working together. [Music]