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  • (Mary) We are on the Kern River Preserve.


  • (Mary) It's beautiful to walk on the preserve this time of year.


  • (Mary) The mornings are really cool.


  • (Mary) This time of year is also amazing because you're hearing


  • (Mary) all the birdsong earlier in the morning.


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  • (Mary) The Willow Flycatcher is this small, plain bird.


  • (Mary) And it flies around and catches flies,


  • (Mary) because that's the type of insect it eats the most.


  • (Mary) And it nests near rivers or creeks.


  • (Mary) Knowing their vocalizations is key to doing the research


  • (Mary) because otherwise, you'd rarely see them if you didn't.


  • (Mary) They say what the flycatchers do is "fitz-bew."

    (Mary)他們說捕蠅者做的是 "fitz -bew"。

  • (Mary) You wouldn't even call it a song, really.


  • (Mary) I mean it's, it's okay. It doesn't sound bad.

    (Mary)我的意思是,沒關係的。 這聽起來不壞。

  • (Mary) I love it when I hear it,


  • (Mary) because it means there's a Willow Flycatcher


  • (Mary) nearby. So, definitely.


  • (Mary) I've lived here in the Kern River Valley


  • (Mary) since the winter of 1990.


  • (Mary) When I first started working here, there were more Willow Flycatchers.


  • (Mary) And now it's down to about, as far as we know at this point


  • (Mary) in time, 1 individual.


  • (Mary) That's all we know of right now and it's kind of depressing.


  • (Steve) As a whole, Empidonax traillii, the Willow Flycatcher,

    作為一個整體,Empidonax traillii,柳樹鶲。

  • (Steve) is not endangered. In fact, it's relatively abundant


  • (Steve) in North America.


  • (Steve) However, the subspecies that inhabits the southwestern United States


  • (Steve) is federally endangered because of rapid and steep population declines


  • (Steve) over the latter half of the 20th century.


  • (Mary) Basically, I view the Willow Flycatcher as a canary in a coalmine.


  • (Mary) It's not doing well, so why is it not doing well here?


  • (Mary) And if you can solve that for the Willow Flycatcher,


  • (Mary) it's probably going to prevent other bird species from having the same problems later on.


  • (Kristen) In the U.S., there's roughly 100 species of neotropical migratory bird


  • (Kristen) that are either threatened, endangered or a species of special concern.


  • (Steve) A neotropical migrant is a bird that breeds in North America


  • (Steve) and then migrates south of the US border, into the neotropics.


  • (Steve) Before I really began to study migration in detail,


  • (Steve) I tended to think of these birds as our birds.


  • (Steve) They're in the North American field guide,


  • (Steve) they must be North American birds, right?


  • (Steve) But they spend, in most cases,


  • (Steve) more than half the year south of the US border.


  • (Steve) Of the nearly 800 species of birds that breed in North America,


  • (Steve) about half migrate into the neotropics.


  • (Steve) It's just a, it's a huge number.


  • (Steve) So if you observe that a migratory bird species is declining,


  • (Steve) one of the first questions you have to ask is whether


  • (Steve) it's declining due to factors on the breeding grounds in North America,


  • (Steve) the wintering grounds in the neotropics,


  • (Steve) or somewhere in between, or a combination of those.


  • (Kristen) The main reason why it's hard to figure out why


  • (Kristen) some of these species are in trouble is because they're only in our backyards


  • (Kristen) for, say, 3 months of the year.


  • (Kristen) And the rest of the time, we don't know where they're going.


  • (Kristen) So we don't know what threats they're facing in those areas.


  • (Kristen) In order to develop conservation strategies,


  • (Kristen) we need to be able to identify how breeding and wintering populations are linked.


  • (Kristen) So migratory bird conservation has to be a collaborative effort


  • (Kristen) with biologists all over Latin America.


  • (Natalie) [speaking Spanish] Yes, taking birds out of the net is one of my favorite things

    (娜塔莉) [講西班牙語] 是的,把鳥從網裡拿出來是我最喜歡的事情之一。

  • (Natalie) [speaking Spanish] because you can learn a lot of new information

    (娜塔莉) [講西班牙語] 因為你可以學到很多新的資訊。

  • (Natalie) [speaking Spanish] when you have a little bird in your hands.

    (娜塔莉)[講西班牙語] 當你有一個小鳥在你的手中。

  • (Natalie) [speaking Spanish] In ornithology, yes, "a bird in the hand is worth more than 100 in the bush

    (Natalie) [講西班牙語] 在鳥類學中,是的,"一隻鳥在手裡的價值超過100只在灌木叢中的價值"。

  • (Natalie) [speaking Spanish] That's the saying, yes!

    (娜塔莉) [講西班牙語] 這是說,是的!

  • (Chespi) More than 220 species of birds actually migrate,


  • (Chespi) mostly from North America, to Costa Rica.


  • (Chespi) Birds know no borders.


  • (Chespi) They don't understand these boundaries between countries.


  • (Chespi) They simply use ecosystems.


  • (Kristen) There are huge networks of people that do bird banding all over the western hemisphere.


  • (Kristen) So you capture the birds in a mist net and you put a little metal leg band on the bird.


  • (Kristen) And then you hope to recapture that bird at some other point in its annual cycle.


  • (Kristen) But the recapture rates are incredibly low.


  • (Kristen) They're less than 1%.


  • (Kristen) So our thought was, well if we could develop a technology

    所以我們的想法是 如果我們能開發出一種技術

  • (Kristen) that could use information within a single feather,


  • (Kristen) like information in the DNA of the bird,


  • (Kristen) to track their migratory movements, then we can take a feather collected from anywhere

    追蹤它們的遷徙路線 然後我們可以從任何地方收集一根羽毛

  • (Kristen) along the migratory journey and link it back to which breeding population that came from.


  • (Kristen) The Bird Genoscape Project is an effort to use genomic sequencing


  • (Kristen) to understand the population- specific movements of migratory birds.


  • (Kristen) The original idea came from the co-director of the Bird Genoscape Project, Tom Smith,


  • (Kristen) who literally just decided about 20 years before the technology was actually


  • (Kristen) available that we should be able to do this.


  • (Tom) In the early 90s, I naively thought that well, if we just collect some feathers


  • (Tom) we'll be able to get DNA out of feathers, and


  • (Tom) it took the Human Genome Project to really develop the tools


  • (Tom) to enable us to begin to link populations.


  • (Kristen) So I live in Colorado now, but if I wanted to know where my ancestors came from,

    我現在住在科羅拉多州 但如果我想知道我的祖先從哪裡來,

  • (Kristen) I might send my DNA off to a genetic ancestry service.


  • (Kristen) They would compare my DNA against this huge database of DNA from


  • (Kristen) many, many other people and be able to identify that most of my ancestry is from Norway,


  • (Kristen) which is where I know my grandparents came from.


  • (Kristen) We can do the same thing with the Bird Genoscape Project.


  • (Kristen) We collaborate with these bird banding stations,


  • (Kristen) which are all over North America and Latin America, to collect feathers.


  • (Kristen) And then our first step is essentially creating that ancestry database.


  • (Kristen) When we sequence the genome from birds all across the breeding range,


  • (Kristen) we use that to build a map of how the different birds are related to one another


  • (Kristen) and what the unique, genetically unique populations are across the breeding range.


  • (Kristen) And then we can take a feather collected from outside of its breeding range

    (克里斯汀) 然後我們可以從它的繁殖範圍外採集一根羽毛。

  • (Kristen) and we can compare that with the expected genetic profile


  • (Kristen) of birds from different parts of the breeding range.


  • (Kristen) And we can tell you that this bird is actually a bird that might be found


  • (Kristen) breeding in the Sierra Nevada mountains, or New York, or something like that.


  • (Kristen) Which is really cool!


  • (Mary) My specific role in the Bird Genoscape Project is collecting genetic samples

    我在 "鳥類基因景觀項目 "中的具體作用是收集基因樣本。

  • (Mary) of Willow Flycatchers throughout their wintering range.


  • (Mary) And then also the breeding grounds as well.


  • (Mary) My role is the fun stuff, I think!


  • [birds chirping]


  • (Mary) I have a speaker and I'm going to use it to do some playback


  • (Mary) of the Willow Flycatcher vocalizations in order to lure it into the net.


  • (Mary) Ok.

    (Mary) Okay.

  • (Mary) And I use a long cord so I'm a good distance away from the net


  • (Mary) and I won't scare them.


  • (Mary) Where'd it go?


  • (Mary) Yep, that's him!


  • (Mary) He was a feisty one, but we got him.


  • (Mary) So this is a Willow Flycatcher,


  • (Mary) and he's not happy. He's a very feisty guy.


  • (Mary) Yeah.

    (Mary) Yeah.

  • (Mary) Here we go.


  • (Mary) OK, so the first thing I'm going to do


  • (Mary) is one of the most important things is to have the genetic samples.


  • (Mary) So I'm going to pluck the tail feather first.


  • (Mary) Sorry, guy.


  • (Kristen) The general sort of description of where the willow flycatcher


  • (Kristen) winters from bird books is from Mexico down to the northern tip of South America.


  • (Mary) When the Southwestern Willow Flycatcher was listed as endangered,


  • (Mary) we had no idea where this particular subspecies wintered.


  • (Mary) Did it go throughout that whole range?


  • (Mary) Or just a portion of the range? We had no idea.


  • (Kristen) Once we have developed what we called the Genoscape


  • (Kristen) the map of how populations are related on the breeding grounds


  • (Kristen) we can take any individual captured on the wintering areas


  • (Kristen) or anywhere along its migratory trajectory


  • (Kristen) and tell you where that bird was from.


  • (Kristen) So the end product of the Bird Genoscape Project for a particular species


  • (Kristen) is the creation of a map that details the genetically distinct lineages


  • (Kristen) and where they're found on the breeding range.


  • (Kristen) Similar to the kind of map that you would find in a bird book.


  • (Kristen) But in this case, it's population-specific.


  • (Kristen) And then it also details where those different populations,


  • (Kristen) which migratory routes they use and then where they're found on the wintering grounds.

    它們使用哪條遷徙路線 然後在哪裡找到它們的越冬地。

  • (Kristen) The Bird Genoscape Project was able to show us with high precision


  • (Kristen) where the wintering areas of the Southwestern Willow Flycatcher are.


  • (Kristen) So people have dedicated their lives to knowing where this bird spends the winter


  • (Kristen) And we know now that it winters in specific areas in Costa Rica and Nicaragua.


  • (Kristen) So now we can really focus our efforts

    (克里斯汀) 所以現在我們可以真正集中精力

  • (Kristen) to where they're needed,


  • (Kristen) which is super cool.


  • (Kristen) That's the whole point!


  • (Tom) Right now we have, just for the neotropical migrants, about 200,000 feathers.


  • (Tom) So that represents roughly around 100 or so species.