How Do We Know that Birds are in Trouble?
In the inaugural episode of Bring Birds Back, host Tenijah Hamilton gets to know biostatistician Dr. Adam Smith, coauthor of the study that found we’ve lost 3 billion birds in North America since 1970, and helps us wrap our heads around that gigantic number. The good news? There are lots of ways to help.
Bring Birds Back is sponsored by the Cornell Lab of Ornithology.
About guest Adam C. Smith:
Adam C. Smith is Senior Biostatistician with the Canadian Wildlife Service and an adjunct professor at Carleton University. He started as a field biologist and over the course of his graduate studies, he fell in love with the data. Now, he specializes in using broad-scale bird monitoring data (North American Breeding Bird Surveys, Christmas Bird Count, eBird, International Shorebird Survey, etc.) to model changing bird populations and to investigate the causes behind those changes.
He is profoundly grateful for the efforts of volunteer birders who have contributed to long-term monitoring projects. We would not be aware of the staggering losses in North American bird populations without the lifetimes of fieldwork from volunteers with the Breeding Bird Survey, Christmas Bird Counts, eBird, and others.
He loves to bird while out skiing, hiking, and canoeing with his family. He is father to two wonderfully boisterous boys, and he is doing his best to allow them to discover the joys of birding on their own.
Tenijah Hamilton: What have you seen of my relationship with nature thus far?
Mom: Okay. So we'll go back to the beginning. Uh, you didn't like it. You never liked it.
Tenijah Hamilton: A little over a year ago, I was not a nature person. Not into hiking, not into camping, never been birding. Growing up, I was what you might an indoor kid, and my mom won't let me forget it.
Mom: If it was summer, you didn't like the heat. If it was winter, you didn't like the cold. You definitely didn't like the bugs. And more than anything else, you didn't like squirrels.
Tenijah Hamilton: You know what? Still don't like squirrels. But the COVID pandemic completely changed my relationship to nature and the outside world. Like so many others, I went from a life of daily commutes and dinner with friends to suddenly getting intimately familiar with all 450 square feet of my studio apartment. The only consolation? A beautiful Boston summer. A closed down road that became a retrofitted river walk, and lots of time in the great outdoors.
Tenijah Hamilton: So, along with my aptly named birder friend, Robin, I spent the entire summer on socially distanced walks, gazing through binoculars, exploring the Boston cityscape and the Greenways. I dubbed Robin an O.G. Bird Girl. And I became known as Bird Girl in Training.
When we would go walking and she would spot a bird, she would always say, "who's that?" Instead of what is that? And it really helped me to remember that these birds aren't just there as part of our bird watching, they're their own beings who have had these whole lives that I had known nothing about. Migrating across continents, building nests, raising their chicks.
And y'all I was enchanted. I was living out all of my Disney princess dreams. I was frolicking in forests with woodland creatures. And instead of my Friday night ritual of happy hours at the stockyard bar, I was, almost daily, visiting a Great Blue Heron friend who lived under an overpass overlooking the Charles River.
I named him Herbert the Heron because I love a good alliteration. I had never experienced the world quite like this. And the desire to connect with it in this new way was something I didn't even see coming.
But, life isn't a fairy tale. Last summer also saw powerful uprisings throughout the country in protest of the state sanctioned violence inflicted on black and brown people, just like me.
George Floyd, Breonna Taylor, and specifically Ahmaud Arbery, who was murdered in broad daylight while out on a run, reminded me again that there is no space where my identity as a black person and a woman can be safely checked at the door. And that has been an inextricable part of my experience as a birder. According to the U.S. Fish and Wildlife Service, as of 2011, the birding community is 93% white.
[Amy Cooper: I'm gonna call the cops!]
[Chris Cooper: Please call the cops.]
Tenijah Hamilton: Last June, we all watch as renowned birder, Christian Cooper, was racially profiled and harassed while out in the ramble in Central Park.
[Amy Cooper: I'm gonna tell them there's an African American man threatening my life!]
Tenijah Hamilton: The situation, where a man was simply exploring the park with his binoculars in search of beautiful birds, only to have what was meant to be his peaceful afternoon, turned into a media frenzy against the backdrop of a national reckoning around race. It felt like the confirmation of my fears and I know I'm not alone.
These fears, the ones we seldom say out loud, echo in our minds when we're worried that we will be unwelcomed in these spaces and met with violence. While the fears brought up by Cooper's experience didn't just go away when the media coverage subsided, I'm heartened to see the way the birding community is making a concerted effort to open up in it's wake.
Last year marked the first Black Birders Week. A week celebrating the many wonderful, talented black folks in the realm of birding. And inviting folks like myself, who may have never felt totally welcome in nature to build kinship and community with them. I'm new to this world and to this work, but I am so happy to be here.
Every day, I'm learning something new. And sometimes, I'm even teaching it. Like this one time when I was on a walk and on the phone with my mom. She was telling me about how she'd seen a Raptor try to steal eggs from another birds nest right on her front porch.
Mom: Oh they attacked him out of everywhere— all the birds— I don't know what language they use, but they put out the 911 call and it was, it was beautiful to see. Because they, they definitely backed him back.
Tenijah Hamilton: And so, here I was on the other end of the phone and I was like, "ah, I know a bird thing". This was the first time that I recognized something I learned from O.G. bird girl, Robin. I was like, oh, I know what's happening here. This phenomena is called mobbing. They were, they were mobbing this predator bird, which— this bully bird.
And it was really special connecting with nature more deeply and seeing it rub off on the people around me. The truth of the matter is, as I began to learn more about birds, the more I realized that they are in very big trouble.
In 2019, a landmark study was published in the journal Science, finding that we've lost almost 30% of all North American birds in the past 50 years alone. That is 3 billion birds— billion with a B— in only one generation.
And in order to bring birds back, we have to invite all kinds of people to the table. And that's why I'm here.
From BirdNote, this is Bring Birds Back. I'm your host, Tenijah Hamilton. My joy for birds comes from learning about others joy for birds. And it makes me want to do my small part in helping to bring them back.
The idea that someone out there will listen to this and find their calling or a career, a new hobby, or even some hope is the thing that lights me up. And like my mom said, I am no expert, but I do get to talk to the experts and bring you with me. So, for our inaugural episode, what better way to start then with that study that found that there are 3 billion fewer birds in North America than 50 years ago.
The study was done by some brilliant biologists and ornithologists, but was only possible thanks to the work of tons of regular, everyday people. Today, I'm talking to one of the authors of that study, Adam C. Smith. And the C stands for counting all the birds and doing complex mathematical equations to predict population decline. I mean, okay, it actually stands for Clark. He's a biostatistician for the Canadian Wildlife Service.
Adam, it is great to have you here with us.
Adam C. Smith: Oh it's great to be here Tenijah.
Tenijah Hamilton: So, Adam, do you feel because of the nature of your work, you are almost prepared for the scope of that loss? It seems incomprehensible.
Adam C. Smith: Even conservation biologists, people who think a lot about birds and populations of birds, we were not prepared for that magnitude of loss. That 3 billion Birds, the vast majority of them are common birds that are ubiquitous in our cities, uh, in our neighborhoods, in our forests, on our farmlands. So we're talking about Dark-eyed Juncos, and Baltimore Orioles, and Redwing Blackbirds, where we've lost tens or hundreds of millions of individuals of each one of those species.
And we lost those species over the span of a single human lifetime. And even biologists and ornithologists and birders, that loss occurred without us really realizing it. We pay a lot of attention to the charismatic species at risk. Those species that capture our imagination because we don't see them every day.
But the species we see every day have been disappearing over the last 50 years without us really realizing it.
Tenijah Hamilton: So for me and a lot of people, it just, really made an impact on my mind when I'm thinking about 3 billion birds. So how did you feel when you first got that result?
Adam C. Smith: Yeah. So as a, you know, statistician, my first reaction when I see numbers that are surprisingly large, is to assume that I've made a mistake.
That's my default reaction, 3 billion, that can't be right. What did I do wrong this time? But after checking the numbers, double checking, triple checking, et cetera, et cetera, I came to realize that that really was the right number. And that's out of a total of 10 billion. So it's almost 30% of the individual birds on the continent.
It's a staggering number.
Tenijah Hamilton: And what is the impact of that on our ecosystem? I mean, you're saying that this happened, essentially, over a span of a single lifetime. That is quick. Um, how have we seen the repercussions from that unfold?
Adam C. Smith: What that 3 billion bird loss really means is that there are 3 billion fewer birds who are out there in the environment, distributing seeds, eating pest insects in our agricultural fields, uh, singing in our neighborhoods, contributing to the functioning ecosystem that supports well the rest of the ecosystem itself, but also, uh, human activities and our food production and our healthy ecosystems that surround us.
Tenijah Hamilton: So I want to put on my little mathematicians hat. This is a hat I do not pull out the box very often. I am a count by my fingers kind of girl. So thinking about the numbers again, how did you even begin to calculate that? What, what did you have to do to get there?
Adam C. Smith: Yeah. So the first thing we had to do was to rely on the tremendous efforts that have gone into surveying and counting and observing birds of the last 50 years. So all of the long-term monitoring programs that government agencies, to some extent, have been contributing to, but also primarily that volunteer birders have been contributing to for the last 50 years. And that's critical. Without those data, we would not be able to run these models. We would not know how those numbers had changed over the last 50 years.
So we had all the data. We've got 50 years of hard work. Lifetimes of work to rely on. And then we took information on the trends in bird populations, the rate of change over time. And then we combined that with estimates of the total number of birds in each species population in the continent. So we have trend information and then we have the size of the population and we combine those two pieces of information, along with estimates of uncertainty of each of those pieces of information, for 529 species.
And then we enter all of that into a fancy hierarchical Bayesian statistical model that accounts for the uncertainties and combines those two pieces of information, and generates an estimate of the number of birds in North America for every year, from 1970, all the way through to 2017.
Tenijah Hamilton: Wow.
Adam C. Smith: And then once we have those annual numbers of birds, then the rest of it is really just counting on your fingers kind of math. We had 10 billion in 1970, and now we've got seven.
Tenijah Hamilton: After the break, we're going to look at the community science and the people power behind these numbers. That's after this.
Tenijah Hamilton: So Adam, I want to talk more about the community science behind these numbers. Like a lot of your research wouldn't have been possible if it wasn't for the folks who've been doing this work for so long.
Adam C. Smith: Yeah.
Tenijah Hamilton: Can you tell me a little bit more about that?
Adam C. Smith: Yeah. And so— like I said, those data are critical. We know more about bird populations and how birds are distributed across the landscape and how they've changed over the last 50 years. We know all of that because of skilled and committed volunteer birders who have contributed to a long-term monitoring program, such as the North American breeding bird survey— in bird circles called the BBS— the Christmas Bird Count and the International Shorebird Survey and other surveys like that.
Rigorous repeated annual samples or surveys of bird populations that go into a central database. And then those data are accessible to someone in my position. So the North American breeding bird survey, for example, that's one of the most critical surveys for North American birds. It provided the information in this particular study for more than 80% of the species in our analysis.
And that program started in the 1960s and those BBS volunteers go out once a year, half an hour before sunrise, and they count birds at 50 pre-identified points along a roadside route and contribute that information to a standardized database. And there are thousands of BBS volunteers across the continent who are still doing that every year.
And there's the Christmas bird count. Audubon has been doing that for a long, long time, more than a— more than a hundred years now— that we use for a lot of the Northern nesting— the boreal and arctic nesting species. The Christmas Bird Count is wonderful in that there is a lot of effort put into it in many different locations.
At each location it's often held on exactly the same weekend and every year. Uh, and so we have this just tremendous time series information on how birds have changed across the continent in the last 50 years.
Tenijah Hamilton: That is wildly cool. Does that make you feel an extra sense of gratification when you're— when you step back and you're like, wow, all these people are helping.
Adam C. Smith: I mean, I swim in gratitude all the time. It's just, it's just incredible. The amount of people's time and effort— not just in going out and doing those surveys every year. I have run a couple of BBS routes myself. I was a birder before I was a statistician and every morning in the month of June, which is when it happens in this part of the world— um, every morning I get up to do a BBS survey, I'm waking up at 2:30 in the morning so that I can drive to get there at the right start time. And I'm imagining all those other hundreds, if not thousands of BBS volunteers across the continent who are probably getting up on that exact same morning, somewhere else, going out and doing exactly the same thing and doing it the same way every year, that give us that consistent, you know, statistically rigorous sample design that allows us to say something, with confidence, about how bird populations are changing.
Tenijah Hamilton: That makes a lot of sense. So I guess to put a little bit of a bow on the community science aspect of this. How crucial is it that people take part in these projects? The North American Breeding Bird Survey, the Christmas Bird Count. Can you just tell us how much of a difference it makes to what you do and you know, our ecosystem and the birds and conservation in general?
Adam C. Smith: It is absolutely critical and it's becoming more and more critical. One of the reasons we know so much about birds goes back to the publication of Silent Spring and the 1960s and 1970s, when at least in North America, we were just beginning to understand the effect that some of our actions were having on the natural environment.
You know, think of Rachel Carson's book, Silent Spring, and she was talking about bird song. And that was one of the reasons that the North American Breeding Bird Survey got started. People thought they had already noticed a change in the bird life around them. And yet they realized that they didn't actually have any hard data to rely on. What they had was this vague notion that, you know, there seem to be fewer Chestnut-collared Longspurs than there used to be. But we don't have any hard numbers to point to. And so they initiated the North American Breeding Bird Survey as a way to generate that solid data on how things were changing. And so when we published our paper in, in 2019, I mean, it's the scientific community, so of course there was a little bit of back and forth with reviewers, et cetera, et cetera.
But there was no significant doubt about the truth of that conclusion.
Tenijah Hamilton: Right.
Adam C. Smith: We have really good information for birds that we don't have for just about any other component of the natural environment. And without those volunteer birders who are doing things like the Breeding Bird Survey, the Christmas Bird Count, those data are absolutely critical to understanding how the natural world is changing.
Tenijah Hamilton: So, how do folks get involved? How do you see, kind of, inviting folks to the table? If you're a beginner, what should you do to be a part of this process?
Adam C. Smith: So I think there's a couple of great places to start. First of all, if you can connect with a local naturalist community, those might be Audubon societies, or they might be independent local groups.
Christmas Bird Counts are another excellent way to get started in that process of gathering systematic observations that are directly contributing to a long-term dataset. And the— one of the really cool things about Christmas Bird Counts is that, because of the way they're conducted, you often end up making those social connections as well.
There's often groups that head out together. Fun activities associated with Christmas Bird Counts that can really help beginner birders. One of the other brilliant things— and this is still relatively new in relation to some of the other programs— but one of the best ways to get more involved in birding is to get connected with eBird and the Merlin app.
Any observation in the eBird database is a useful component that is archived for the future. And they are going to be more and more and more important as time goes on. And, you know, folks in my position are working at ways of integrating the Breeding Bird Survey with eBird data so that we can get an even richer description of how bird populations are changing in space and time.
So eBird for sure is a brilliant source for people to get involved.
Tenijah Hamilton: So if you are a more experienced birder, which is something you talked about a little earlier, you'd recommend the North American Bird Survey? Getting down with those folks?
Adam C. Smith: Yeah, absolutely. And if you are— if you are an experienced birder, then absolutely get in touch with your, your provincial or state coordinator for the North American Breeding Bird Survey.
And there's this 50 plus year time series now that, as a skilled birder, you can contribute to. And if you're north of the border is all kinds of cool stuff going on with Birds Canada as well. Uh, the Christmas Bird Count in Canada. And they do loon surveys, annual surveys for loons on lakes. They coordinate nocturnal owl surveys.
They're really fun. You go out and you broadcast owl calls and then listen to hear what comes back.
Tenijah Hamilton: That's pretty awesome. Okay, so we are going to make sure that we have links for all of that on our website, so people can reference all these really cool things that you're talking about.
Adam C. Smith: Super.
Tenijah Hamilton: Conservation can sometimes be daunting as we, kind of, talked about at the top of the show.
It can feel a little disheartening, especially when you're looking at really big numbers. For you, what's the thing that keeps you going and makes you feel hopeful at the end of the day?
Adam C. Smith: So one of the neatest things that came out of this particular study and it's— but that— it's a pattern that's shown up in other, uh, in other work as well.
But even though there was a, uh, an overall loss in the number of birds in North America in the last 50 years, there are two groups that stand out because of their increases. So waterfowl have increased. There are more ducks, more geese, more swans in North America than there were 50 years ago. And Raptors, there are more Bald Eagles, Peregrine Falcons, Ospreys, et cetera, et cetera in North America than there used to be 50 years ago.
And both of those groups have recovered largely as a function of things that we have as societies— that we have deliberately done to make things better for birds. So the Raptors have recovered, largely— we talked about the Silent Spring before— Raptors have recovered in essence because we stopped spreading DDT.
We banned DDT. We did the science back in the sixties and seventies and eighties to understand what was happening, to understand the problem in the natural environment. And then we took action based on that scientific research— based on the results to ban that chemical and Raptors and Waterbirds and others recovered as a result of that.
On a canoe trip last year, my kids got bored of seeing Bald Eagles now— you know— and that's, that's something when I was a kid that did not happen, we didn't see Bald Eagles. They weren't anywhere. I was my twenties before I saw my first Bald Eagle in the flesh and we were on a canoe trip and they— we just kept seeing them. We were seeing them every day. That change that has happened in the span of my lifetime, so that my kids now can see so many Bald Eagles, they're like, "Oh yeah, look another eagle", that's brilliant, right?
Waterfowl came back, basically, because we improved the protections for wetlands and we've done a better job of managing hunting over the last 50 years than we had been before that.
And so those were actions where we did the science, we did the homework to understand what was happening, and then we took action based on that understanding. And the birds recovered. And so even within that overall loss, there are two examples that can point the way to how to fix things. To how we can recover that 3 billion birds.
Tenijah Hamilton: So Adam, you are telling me on the inaugural episode of the Bring Birds Back podcast that we have brought birds back before, and we can do it again.
Adam C. Smith: Absolutely.
Tenijah Hamilton: That is something worth being excited about, setting that precedent, moving forward. We've done it before and we can do it again.
Adam C. Smith: Yeah. Yeah. All it takes is understanding the science, understanding the system and choosing as a society to take action to make things better.
Tenijah Hamilton: Thank you so much, Adam. It was great to have you on our first episode.
Adam C. Smith: Thank you very much.
Tenijah Hamilton: I'm going to be honest, when I first heard that 3 billion birds figure, I wanted to tune things out. It is such a scary, big problem. What can little old me do about it? But it turns out there are a lot of ways we can lend a hand. And that's what this podcast is going to be looking at ways that we can all help birds.
We'll go into the many actions that make a difference and meet folks who are doing amazing work to help bring birds back. And hopefully you can grow to love birds more with me as I learn about what makes them so incredible.
Tenijah Hamilton: So Ma are you going to, are you going to listen to my show?
Mom: Sure thing. I love to learn more about why we should bring birds back.
Tenijah Hamilton: You heard her give the show a follow. You can find it in your favorite podcast app, like Apple Podcasts, Overcast, or Spotify. Or you can listen on our website, Birdnote.org. Bring Birds Back is produced by Mark Bramhill, and me Tenijah Hamilton. We're edited by Oluwakemi Aladesuyi. Our content director is Allison Wilson. Our lead science advisor is Trina Bayard. Music by Cosmo Sheldrake and Blue Dot Sessions. Special thanks to Rehka Murthy.
Thanks to our season sponsor the Cornell Lab of Ornithology. Check out all they have to offer like Bird Academy, online courses and the Merlin ID app, at AllAboutBirds.org.
See you next time.
Mom: Hello, Bird talk audience.
Tenijah Hamilton: Not the name of the show.
Podcast art by Hayden Maynard.