Science Friday
Hosted by Ira Flatow
This Christmas Bird Count, we salute the fabulous, underappreciated, common species. Here's to you, house sparrow.
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Hey, I'm Kathleen Davis, and you're listening to Science Friday. Today on the show, it's that time of the year again, the Christmas bird count.
No, not that one. The one where birders go out in flocks to record all the birds that they see in a single day. The data that's collected during this annual holiday tradition gets sent to the National Audubon Society, where it helps scientists understand bird population trends across the Americas. But most of the birds you'll see are the birds that you're likely to see any other day of the year. Think sparrows, blue jays, blackbirds, cardinals. So this year, we're turning our binoculars towards a few wrongfully overlooked birds. Joining me now are two of our favorite birders to share some surprising facts about birds that don't often make it to the top of the pecking order. We have Corinna Newsom, conservation scientist
at the National Wildlife Federation. She's based in Atlanta, Georgia, and author and illustrator Rosemary Moscow. Both of you, welcome back to Science Friday.
Thank you so much for having us.
Hi, I'm so excited to be here. Bird party.
Rosemary, I want to start with a bird that I know that I personally see all the time where I live in New York, and that is the house sparrow. You recently wrote about the surprising history of this bird. How did they end up here?
This is one of my absolute favorite stories and I want to say I love familiar birds because of what they tell us about ourselves as opposed to just about the birds. So this is a bird where, you know, it's all over the place, but it is not native to North America at all. So the reason it was brought over here was as a biocontrol, believe it or not. So it was brought over here because in the 1800s, there was a horrendous problem with caterpillars, especially this one brown caterpillar called the elm spanworm that would hang from trees and land on people and eat leaves. And there are descriptions of men complaining because these caterpillars are dangling from their mustaches. And so
God forbid.
I know, God forbid. And women were fleeing the, the safety of the shade to bake in the sun because of these caterpillars. So, so a group of, as the newspapers called them, intelligent men got together and imported house sparrows to eat the caterpillars in about 1850. So they were very intentionally imported to try to fix a problem. And then of course, as we know, they spread absolutely everywhere and became a little less popular as time went on.
Okay, so this is an invasive species that humans purposely introduced. Should we still love them?
You know, this is such a complicated question. My main opinion is that we shouldn't hate them. We shouldn't blame them personally for any problems that they create because, as I said, we brought them here intentionally. I think that you don't have to love house sparrows. I mean, they cause problems. They especially spread certain diseases to other birds. They can spread West Nile, for example. And we do know that they will compete with birds like bluebirds for, for nesting boxes, although there's some question about the overall population effects that they have on a, on a grander scale. There's still a lot more information that we have to kind of dig up and explore there. But I think
that we can look at them as symbols in, in some senses of resilience and also as telling us an awful lot. About our personal history. So when they first were brought over to North America, people wound up equating them with immigrants and having a lot of anti-immigrant sentiment that they were kind of channeling through these birds in ways that had nothing to do with with science, nothing to do with anything factual. They were sort of getting out their, you know, hatred of immigrants through these birds. And if you read the literature there, it's so interesting to look at the way we were kind of scapegoating these birds. And so I think they they teach us about how we treat other humans and also that we need to look at science
and not necessarily focus on our sort of personal loathings that may be problematic and rooted in some some rough history.
Wow, I never would have thought that such an unsuspecting little bird would tell us so much about us as people and and have such a complicated history.
I wanted to say that I really appreciate you saying that the fact that they're common is an important and maybe even special thing. And it's making me think about like my young niece, I think she was around seven years old. She went on her first birding trip. It was a blackbirders trip in Philadelphia and we went around and said our favorite birds. And she said her favorite bird was the house sparrow. And I was so grateful that she was in the environment that she was in that celebrated this being her first bird because had she been in the wrong environment, she could have been very quickly condemned. I've seen that. But when asked, you know, why is this your favorite bird? She said, because I can see it so easily. You can see it without really trying. And the accessibility that house sparrows bring, even without thinking so much about their ecological impact, their disease ecology and all those kinds of things, like just the fact
that they can be seen in so many places makes them so important to intro birders, young people who are kind of foraying into loving birds more and more.
Let's move on to another bird that I am seeing all the time right now, and that's blue jays. Karina, tell me a little bit about the blue jay. What makes them so special?
Oh, man, blue jays are special for so many different reasons. Their behaviors are fairly unique among songbirds. They're in the corvid family, so they're related to crows and ravens. They're the ones that we see probably most often in backyard, especially feeders. They're great mimics. Have been multiple times where there has been a blue jay around that I thought was a red shouldered hawk. They're for some reason really into mimicking red shouldered hawk calls, which I really enjoy. And it's pretty effective because it scares away other birds from the feeders and then they can go and kind of monopolize the food source. So they know how to manipulate their environments pretty well. And they have really large like ghoulers pouches, is what it's called, inside of their mouth that allow them to stuff huge nuts into their
mouth and carry them off. And similar to squirrels, you may, if food is pretty abundant, you may see them caching these nuts. They might kind of dig into the ground and cover it up with some leaf litter or grass, and they will come back for it later. So they kind of do a lot of behaviors that you might miss if you're not watching them very closely, but so much to uncover with the blue jay.
Wow, that's incredible. Okay, I want to talk about two closely related birds, and that's the titmouse and the chickadee. They also have some important vocalizations. Can you tell me a little bit about them, Karina?
That's true. So I always, whenever I think about titmice, and especially titmice, but titmice and chickadees, they are among birds that you'll see like in forested ecosystems or in backyards, they want the smoke. If there is a even potential threat nearby, they're going to be the first to say something. And they are so quick to respond to the presence of like a predator or, you know, a threat of some kind that other bird species, other taxonomic groups entirely, like squirrels, will respond and will come rushing to the scene to see what's going on. Their vocalizations are doing a big service for all kinds of wildlife in the backyards, in the forest, across, especially eastern US.
Can you do a call for us?
Oh, my gosh. I was literally afraid you would ask me to do this.
This is on you or Rosemary, but I need to hear it.
Rosemary, I'll, do you, do you feel like you have that in you?
All right, let me try, let me try, let me try. Okay. Do I can do a chickadee?
But I can't do a titmouse. Okay, titmice to me are so cute, but most of their sounds are not. Like, they're sort of like, they're sort of like-
Describe it for me.
Okay, here's, here's my best impression of a titmouse. So it'll be like a
like, like, kind of like that, but much higher pitched.
That was good.
Okay, I appreciate it. When they do that,
I wish-
it's on.
I wish you guys could see my face. Um, that's amazing. Okay, Rosemary, let's talk about the cardinal, which is an iconic winter bird. You know, they have these bright red feathers. They are gorgeous on a snowy Christmas card. Um, but they're not always so glamorous looking, right?
Yeah. Okay, so one of my absolute favorite things in the whole world is when cardinals and some other birds will do this too. At the end of their, their breeding season, when they no longer have to look so pretty, they will molt. Uh, and you know, this is a standard thing. Birds will molt their feathers and then get new ones. But cardinals especially, uh, will molt sometimes all of their head feathers at once. Um, people who have seen that, that old movie, The Dark Crystal will say that they, they look like the Skeksis from The Dark Crystal. They're like, very, very strange looking with their giant bills and their kind of like wrinkly pink purple skin. Um, and I, I love this because it turns out that they do this pretty naturally. It, it doesn't seem to be generally
caused by any kind of illness or mites or anything. They will just drop all their feathers at once because they don't have to look pretty right now. And, uh, I love, uh, finding posts online from people who are just absolutely panicked, like, what is wrong with my cardinal? There's this cardinal in the backyard and it looks, it looks terrifying. So I made a comic about it a couple of years ago, where I had a guide to different, um, different northern cardinal appearances. And then for the bald one, I, I named it Blood Cheap, the frightful molt demon of the cursed abyss. And I put a bunch of umlauts in Blood Cheap because I'm kind of a metal fan. So like these fake umlauts. And I put it up and I thought, okay, maybe I'm just odd and nobody will find this funny. And I've since learned
that there is a, an entire, like, uh, group on Reddit, a subreddit called Blood Cheap, where people post their naked cardinals and other birds too. So they've like expanded the universe. So they're like blue cheeps, which are blue jays, which will also very commonly molt their head feathers. That's funny. In fact, the most terrifying one that I have personally ever seen was a titmouse. I once saw- A titmouse that had dropped all of its head feathers. And I don't know how to describe it, but birds just have such big eyes and beaks. And everything else is so small that when the feathers are gone, it's one of the strangest things I've ever seen. So yeah, it's, I feel like really thrilled that, that blood sheep has become, has become
a thing now and also that it's helping people be less worried for their backyard birds. That they're okay.
I mean, when would be the prime time to find these freaky little baldies?
Sadly, we have passed peak blood sheep season. So it's, it's sort of around August, September is when you will, when you will see it. And then by now they will have a new, a new bunch of feathers. But keep your eyes out around that time and, and hopefully you will be blessed with a visitation from, from blood sheep.
We have to take a break. And when we come back, why you should consider a cloud of blackbirds a good omen.
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Okay, let's move on to another bird that people may be familiar with and do a little myth busting. So Karina, blackbirds have kind of a reputation for being a bad omen. Should you be worried if you see a cloud of blackbirds, which I recently learned is the plural for blackbirds?
Nice, nice. It is actually quite the opposite. Whenever I'm online, it's usually TikTok where I see this, when people see large groups of black colored birds, whether it's vultures, but especially blackbirds, like people are genuinely existentially fearful. And to me, and realistically, this is a good thing. This means that there is habitat available to support these large numbers of blackbirds. And of course, sometimes when they descend upon things like a Home Depot parking lot and are covering cars, you know, like by the dozens, that can be fairly alarming. But one of the cool things in winter in particular, blackbirds, mixed species flocks. You'll have grackles, you'll have red-winged blackbirds, species like that.
They'll congregate, especially as the sun is going down, as they're getting ready to go to sleep for the night. They'll congregate in these huge flocks. And when I say huge, I mean like hundreds of thousands of birds, or even more sometimes. And for example, here in Atlanta, there's a wetland area in Clayton County, which is like a little south of Atlanta, where blackbirds, they sleep during the winter. One time, I was able to go to this wetland early in the morning before the sun really came up. It was like five something in the morning, and it's a spectacle to watch them all emerge. Because what happens is, again, about a million blackbirds, you can't really see any of them. They're kind of below the top of the grass, but you can hear them. They're doing their kind of high pitched, screechy, metallicy sound.
And then all of a sudden, they went completely quiet, not a single one making any noise. And then they took off at the same time. The sound of their wing beats when they did that, it felt like, if you've ever been at like a wedding with a good DJ, or like in the club, and you have like 808 speakers, and you can feel like the bass in your bones, like in your chest. It was that loud and that deep. When I tell you, I wept cold tears in the winter air that morning. I have never heard or seen anything like that. So if you see blackbirds in huge groups, that is an amazing omen. It's a good omen. Think of it even as good luck and spread the word if you can. So we have fewer panicked people making posts on Instagram and TikTok.
Okay, Rosemary, we have to talk about pigeons because you are the pigeon queen. They are kind of the ultimate common, taken-for-granted bird. Give us one unexpected pigeon fact, please.
Oh, no, only one.
You have to pick your favorite.
Oh, gosh. Okay, well, one of my favorite pigeon facts is, so pigeons are, as hopefully people are slowly, people are slowly rediscovering, which is making me really happy, they are domesticated birds. They were domesticated sometime that is lost to the mists of history because it was before the dawn of recorded writing. So they were brought over to North America because they were considered so useful and important. And then we sort of forgot their usefulness, and now we get annoyed by these pigeons that are all around us. But one of my favorite facts is that they were very important during both world wars, and in fact, during many wars and many other times before that, as message carriers.
And so whenever people knock pigeons, I like to say, okay, so there was a medal that Britain put out for animals that were brave during World War II, and a whopping 32 pigeons won this medal. It was called the Dickens Medal, and they would have carried important information from troops that, you know, for example, were behind enemy lines, were being hit by friendly fire, or whose plane went down. So 32 pigeons, just in World War II, were heroic. And do you want to know how many cats won the Dickens Medal?
Please.
One. There was one cat. And this cat, I believe it won for, I think, killing some rats on a ship. So, you know, I love cats, but I just want to say 32 to 1 is pretty darn impressive for my pigeons.
It's a good ratio. Okay, so logistically, so you go out and you count 100 pigeons on your Christmas bird count. Is that data helpful for scientists? Because we're not really worried about the pigeon population, right?
I think it really is. I think that what is really interesting about collecting information about really common birds is that often what affects them is also what is affecting the rarer birds. And even if not, you know, even with birds like pigeons who really are relying on us to create the habitats that they love, charting changes in their abundance can tell us a lot about how our environments are changing. There was a really fascinating study that came out a few years ago that looked at lead levels in the blood of pigeons and also lead levels in the blood of children that were living in the same areas. And they found that pigeons
are really reliable indicators of toxic levels of lead in kids' blood. So what happens to the birds around us also happens to the people. And so it can be valuable information, not just for conserving birds, but also for for teaching us about what's happening to our environment.
Well, thank you both so much for bringing some wonder to the magical world of neighborhood birds.
Thank you. This was so much fun.
Thank you so much.
Karina Newsom, conservation scientist at the National Wildlife Federation. She is based in Atlanta, Georgia, and author and illustrator Rosemary Moscow. And we want to hear from you. What is your favorite common bird and why? For example, do you love geese? Do you find them majestic and sassy in a good way? Your challenge is to convince the rest of the world to love them, too. Give us the hard sell on your softest, fluffiest, most underappreciated neighborhood bird. Give us a call at 8774-CY-FRY. That's 8774-CY-FRY. Today's episode was produced by Shoshana Buckstom. I'm Kathleen Davis. Thanks for listening.
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