The Science of Birds - Answers to Your Questions About Birds - AMA - Vol 4

Episode Date: May 15, 2024

In this episode—which is Number 96—I’ll be answering questions sent by my listeners. So this is what we call an “Ask Me Anything” (AMA) episode. I enjoy doing these, and it’s so interesting to see what sorts of questions people have about birds.The listeners who get to contribute questions for these Ask Me Anything episodes are members of my community on Patreon. There are several tiers of support that people can join, and at the Helpful Hornbill and Awesome Osprey level, one perks is getting to ask questions for episodes like this one.So if you’d like to have me answer your bird questions in a future episode, consider signing up on my Patreon page, and become a Helpful Hornbill or an Awesome Osprey. I got lots of participation this time and some great questions. Many of the questions submitted are about things I hadn’t thought about before. Some of them are sort of out of left field… Which is so cool. The curiosity and unique perspectives of my listeners—you guys—drive me to expand my own understanding of birds. And I love that! Links of Interest Male Montezuma Oropendola song and bow display [VIDEO] ~~ Leave me a review using Podchaser ~~Link to this episode on the Science of Birds website Support the show

Hello and welcome. This is the Science of Birds. I am your host, Ivan Philipson. The Science of Birds podcast is a lighthearted exploration of bird biology for lifelong learners. In this episode, which is number 96, I'll be answering questions sent by my listeners. So this is what we would call an Ask Me Anything episode. I really like doing these,

and it's really interesting to see what sorts of questions people have about birds. The listeners who get to contribute questions for these Ask Me Anything episodes are members of my community on Patreon. There are several tiers of support that people can join, and at the helpful hornbill and the awesome awesome, Osprey levels, one of the perks is getting to ask questions for episodes like this one. So if you'd like to have me answer your bird questions in a future episode, consider signing up at patreon.com slash science of birds and become a helpful hornbill or an awesome osprey.

I got a lot of participation this time and some great questions. Many of the questions submitted are about things that I hadn't thought about before. Some of them are sort of out of left field, which is cool. The curiosity and unique perspectives of my listeners, you guys, drive me to expand my own understanding of birds. And I love that, because honestly, with many of these questions, I don't have the answers pre-packaged and already rolling around in my brain to figure out the answers I have to do some homework, some research.

And even then, there isn't always a definitive answer. Sometimes these questions bring our attention to some unanswered bird mysteries. And that, too, is super cool, I think. All right, we have a lot to talk about, so let's get started. I've grouped today's questions loosely by topic. First up, we have a question from my Patreon member, Ryan. He asks, how many bird species potentially new to science do you think are left in the world? That's a great question, Ryan. Personally, I'm fascinated by the diversity of birds at the

levels of species, family, and order. And how biologists discover and define species is a fascinating topic in itself. At the moment, ornithologists have identified about 10,800 bird species alive on the planet. Bird experts regularly update this number every year as they continue to refine our understanding of which birds deserve to be treated as genuine species. This is no simple task. It isn't always clear which birds represent species and which should be treated as subspecies or hybrids or whatever. If you'd like to learn more about the ways scientists define bird species, go back and listen to episode 15 of this podcast. Anyway, species can be distinguished by physical differences like plumage structure and color, by eye color, egg color, etc. Or species can

sometimes be distinguished by behavior or by their songs. Using physical and behavioral traits like this is the more traditional way of defining species. For the last 20 years or so, however, the best data source used to tell one species from another has become genetic information from DNA. Genetic information, sometimes combined with data about physical and or behavioral traits, is often used by ornithologists to split one species

into two or more species. The data tells us that what we thought was just one species is actually two or more species, and so we need to update our classification system. That's what we call splitting. But it goes the other way, too. Sometimes ornithologists look at the data, and they realize that two or more birds that we thought were separate species are actually so similar at the genetic level we should reclassify them as belonging to a single species.

When this happens, we call it lumping. Ornithologists doing all this splitting and lumping are trying to create the most useful and most accurate taxonomy, a system of classification for birds. Ideally, this taxonomy reflects the true genetic and evolutionary lineages that exist among birds. It should tell us about their evolutionary history. I don't own a copy, but there is a book called Birds New to Science.

The author is David Brewer, and it was published in 2018. The book covers about 300 species that were discovered or described between 1960 and 2018. But in a way, that book is already outdated, right? Because, quote-unquote, new bird species are added almost every year. New species are added in one of two ways. First, a bird species might be a genuinely new discovery,

as in some ornithologists went to some remote place, bushwhacked through the jungle and found a bird that has never been described by Western scientists before. A major discovery like this happened in 2020 when a group of scientists found five new bird species on a couple tiny islands off the east coast of Sulawesi in the Indonesian archipelago. Examples of the new birds are the Taliabu leaf warbler, Pelang leaf warbler, and the Taliabu Mizamela. The second way that new bird species get added to the global liver,

is through splitting, which we already talked about. So, for example, in 2023, the most recent update of the Clements checklist of birds of the world, the list used by eBird and all of those guys, the most recent update added three newly described species. The wangy, wangy, white eye is one example. And that's a fantastic name, isn't it? Wangy, wangy white eye. Then there were 124 new species added to the checklist.

because of splits. But where there's splitting, there can also be lumping. Sixteen species were lost in 2023 because of lumping. So the net gain in species was 111 for that year. Let me finally answer Ryan's question. The question is, how many bird species potentially new to science do you, Ivan, think are left in the world? Now, obviously I can only speculate.

But I'd say that through the process of splitting, there are still quite a few bird species that ornithologists will be able to identify. But who knows, maybe taxonomic splits will give us another 500 species, a thousand? But adding new species the other, more traditional way, as in going on an expedition and finding them on a remote island or wherever, I think we won't be adding too many more bird species that way, maybe another 50 at most. Part of me kind of wishes I lived in the age of discovery, or even into the 1800s, when it was still possible for a Western scientist or naturalist to step on the shores of some new land and find countless new birds and other animals, species that would be new to science. But alas, those kinds of experiences are pretty much a thing of the distant past.

Maybe when humans start landing on distant planets, we can once again experience the thrill of discovering new species. I mean, just think of all the space birds that must be out there, waiting to be described and named and put on a list by us. Space finches, space hawks, space penguins, space turkeys. It's going to be amazing. Next up, we have a few questions that are all related to long-distance movement and migration. in birds. The first comes from Alicia. She says, I'm wondering what happens to vagrants. Do they make it back to

where they're supposed to be, or are they lost forever? Okay, cool. So we're talking about vagrants. First, we should probably get on the same page about what this term means in the world of birds. I just pulled a book called the Ornithologist's dictionary off my shelf, and the definition it gives for vagrant is, quote, a rare visitor found far beyond its normal geographic range, typically recorded only once or twice in any area in question, also called stray or accidental, end quote. Vagrancy is an interesting topic, and I plan to do an entire episode on it. Vigrants are interesting to scientists, but also to birders.

When, for example, a massive stellar sea eagle shows up in New England, like one did in 2021, birders in the region freak out and rush out to see the bird. I know I sure would, because Stellar's sea eagle, a cousin of the bald eagle, is normally found only in the far east of Asia, like in Siberia, so on the opposite side of the planet. Seeing this species in Maine, for example, would probably be a once-in-a-lifetime experience for a birder. I'm just guessing that some of you listening right now have seen that exact bird. And that particular eagle stuck around the east coast of North America until at least the winter of 2023. But I'm not sure if anyone knows where it is now. I tried to figure that out. And that brings us back to Alicia's

question. When a bird ends up so far from its normal home, what is its fate likely going to be? Naturally, the answer is going to vary on a case-by-case basis. But my understanding is that most vagrant birds aren't going to live all that long, especially if they end up in what is, for them, a totally strange habitat with unrecognizable prey or food plants, and or if the vagrant isn't adapted to the local climate. That's a sad thought, right? None of us wants to see a vagrant suffer and die, but this is the harsh reality, most likely for many of them. That said, there are rare cases where the bird miraculously finds its way home again. Another possibility is that a vagrant bird survives for years and years in the place it

accidentally ended up. It lives out its semi-natural life. For example, some vagrant black-browed albatrosses have returned year after year to hang out in northern Gannet colonies in the Atlantic Ocean. Black-browed albatrosses normally live in the Pacific Ocean. But even if a vagrant bird survives for years in its adopted home, it probably isn't going to breed. The chances of another vagrant of the same species showing up in the same place is exceedingly rare. A vagrant sea eagle or albatross or whoever is most likely going to live as a bachelor or bachelorette for the rest of their days. Unless, unless the cause of the vagrancy in the first place was a storm that blew a flock of birds to the same far-flung

location. And such things do happen. For example, a flock of ring-necked ducks landed in Western Ireland in October 2008 after an Atlantic storm. That sort of thing is rare, yes. But it happens often enough over thousands or millions of years that it's a major way that birds have colonized just about every corner of the planet. The Hawaiian archipelago, for example, is one of the most isolated island groups in the world. And yet, birds of many kinds made their way to Hawaii and set up shop. They survived, made babies, and evolved into wonderful new species. So at least sometimes the story of a vagrant bird can have a happy ending. The next question, also about migration, was submitted by Kyle.

He asks if there is, quote, an update on phenological mismatch and annual migration. Have birds been adapting on a macro level or trend? End quote. This is a good question, one that has to do with the effects of climate change on birds. Kyle used some fancy scientific terms in his question. that I should explain first. He's asking about phenological mismatch or phenological mismatch. Phenology, spelled P-H-E-N-O-L-O-G-Y, is the study of cyclical and seasonal patterns in bird behavior and physiology, especially as they're related to things like weather and climate.

Some seasonal patterns in birds that fall under the topic of phenology include migration, breeding and molting. Okay, so that's phenology. What then is phenological mismatch? This is what happens when the seasonal timing is misaligned or off between the availability of a resource on the one hand and a species demand for that resource on the other hand. The two events are mismatched in time.

They're not synced up. Let's say you've got a migratory bird species. When the climate was relatively normal, like 300 years ago, this hypothetical bird species would arrive in North America in the spring at just the right time to feed on hordes of grasshoppers emerging from hibernation. Over evolutionary time, the bird had adapted so that its phenology closely matched the phonology of the grasshoppers. But in the present, springtime temperatures in North America are warming up earlier and earlier because of climate. climate change. Spring is coming earlier. This has caused the grasshoppers to emerge three weeks

earlier because they respond to temperature. Unfortunately, our bird species is still driven by its old instincts. Climate change has happened so quickly that this bird hasn't had enough time to adapt to the new conditions. These birds still arrive at the same time of year that they have for thousands of years. But now, when they reach North America, there are three weeks too late. The grasshoppers have all been eaten up by other predators. This is kind of like when I show up at Taco Bell at 6 a.m. on Thursday, like I do every Thursday to get myself breakfast. A. Chalupa Supreme, some nacho fries, and five or six spicy potato soft tacos. But what if I showed up at 6 a.m. and little did I know my local Taco Bell changed their hours

and now they don't open until eight. Such a phenological mismatch might result in my death by starvation. Or at least I'd feel mildly hungry for about two hours. But those birds that showed up three weeks too late, they really are at risk of starvation. That would be a real phenological mismatch. Now I think Kyle wants to know

what the current understanding among scientists is regarding birds and phenological mismatches. Have some birds been able to adapt? This is actually a pretty big topic, so I can't go into all of the detail today, and it's definitely an ongoing area of research. But there's at least one important study I can highlight. It was published just last month in PNAS, the Proceedings of the National Academy of Sciences, which is a well-respected authoritative journal. In this study, the researchers looked at the timing of migration

in 150 bird species in the Western Hemisphere. They also looked at the historical and present-day timing of what's known as spring green-up. Green-up is when habitats explode with new plant growth in spring. The landscape literally greens up. And this is closely followed by a big pulse of biomass in the form of insects and other potential prey animals. Importantly, the timing of when greenup happens

is strongly affected by local temperature. Looking at data from 2002 to 2021, the researchers found that the migrations of most bird species are more in sync with the historical long-term average of spring greenup. Most of those 150 bird species have not adapted to the timing of greenup as it's been happening more recently. In a warming world, spring comes earlier and earlier on average. We might think that birds are smart enough to recognize that spring is arriving early in a given year.

Now, birds are indeed very smart, but the signal, the cue that many, if not most, species used to begin their spring migrations is not temperature. Instead, the cue they use is day length or photo period. In other words, it's not like a bird in its wintering habitat walks up to its friends and says, Hey, fellas, is it just me or does it feel a lot warmer than usual for this time of year? Like, I seriously just pulled my shorts and flip-flops out of the closet. So I'm thinking we better head north to make sure we don't miss the spring greenup. But to repeat, most birds do not respond to temperature like that.

They respond to the amount of daylight each day. The photo period. The problem is that the photo period at a specific location on a specific date never changes. It's the same year after year no matter what the climate is doing. Birds can adapt to climate change. They've been doing that for millions of years, right? But the challenge is that human-caused climate change is happening really fast, so fast that many species haven't been able to evolve to adapt fast enough.

The phenological mismatches detailed in this recently published study aren't happening to just one type of bird. Mismatches were found across many bird families, from waterfowl, shorebirds, and hummingbirds to raptors and songbirds. Mismatches are occurring in both long and short-distance migrants, and among both herbivorous and carnivorous birds. But I know of at least one bird species that seems to have avoided any phenological. mismatch. McQueen's Bustard, Klamadotus McQueenie, is a large Asian bird. Another name for this bird is the Asian Hubara. Populations of this species that breed in Central Asia are long-distance migrants. Apparently, McQueen's Bustard does use local temperature as the queue to start its long northward journey in spring. A paper published in 2021, also in the journal PNAS, looked at phonology

in this species. The researchers point out that because this Bustard species uses temperature as its migration queue, rather than photo period, it's pre-adapted to respond to climate change. It can adjust the timing of its migration to match the timing of Greenup. Danny asks our next question. She writes, quote, for the past two years, I've lived along the North American Central Flyway. Twice a year, I see tens of thousands of Canada geese coming or going in what my partner and I call loud clouds, flocks of hundreds of birds that follow their migration routes with a distinct honking chorus.

I've seen snow geese, sandhill cranes, and ring-billed gulls flying overhead this way, sometimes making an absolute racket and sometimes without a peep. Do we have an idea of why sometimes flocks tend to be on full blast and other times silent, especially during migration? End quote. Loud clouds. I love it, Danny. Yeah, so Canada geese and some other birds that fly in flocks during migration call loudly to each other,

especially waterfowl. Most of us have witnessed this before. In a more general sense, birds of many kinds often call to each other while flying around in a flock. It's a way for them to keep in contact with their buddies. Ornithologists call these vocalizations contact calls. These relatively short, simple sounds are little exclamations. Each bird is yelling to its pals, hey, hey, here, here, I'm over here, hey! But the honking sounds of geese are perhaps a little more specialized. Geese are famous for flying in V formations during migration. This is a behavioral adaptation that allows the geese to save energy on long flights.

While in a V formation, a goose can get a bit of extra aerodynamic lift from the air currents spinning off the wingtips of its friend flying just ahead. So a goose behind another goose doesn't need to burn as many calories while flying. However, the lead goose, goose, the one at the front end of the V, doesn't get this benefit. So the geese rotate their positions within the formation every so often. Isn't that ever so courteous of them? Some researchers hypothesize that the noisy flight calls made by geese help them coordinate their position changes within the V. Now, as to why these same flocks sometimes fly silently as Danny has observed? I don't know. I couldn't dig up any research that

explains this. Maybe nobody knows what causes these loud clouds to occasionally turn into soundless clouds. The next couple of questions have to do with breeding in birds. The first one is from Emily. Emily was watching a nest cam of barn owls in Indiana this spring. Of the seven chicks that hatched, none of them survived more than a day, sadly. The male owl, dad, did his job in bringing small rodents to the nest, but these went uneaten for some reason. And Emily observed the female owl occasionally stepping on her nestlings, presumably by accident. It's uncertain how old this female barn owl is, but folks watching the nest cam speculated that she's young and inexperienced.

to when it comes to raising a family. So, Emily's question is this. Quote, do older, more experienced birds generally have a higher success when it comes to getting chicks to the point of fledging? If yes, is this effect more pronounced

in species with longer average lifespans, or maybe in more social species? The answer is, yes. Yes, there is a lot of scientific evidence that older, more experienced birds tend to have a higher success rate in raising chicks to the fledgling stage. And just as a reminder, a fledgling is a very young bird

whose bones, muscles, and feathers are finally large and strong enough to support flight. The fledgling stage is when a bird can first fly. Let's imagine a graph of breeding success. And this graph will also show us the typical pattern for many birds. On the y-axis, we have the number of surviving fledglings. From bottom to top, it goes from zero to, let's say, 10. The X-axis is the age of the parent in years, which increases from left to right. The line plotted on the graph reflects the relationship between the age of a parent bird and its reproductive success.

The line starts low on the left because young parents aren't all that awesome at raising babies. Then the line goes up steadily for a few years. It peaks around middle age for the parent bird. Then it either goes down steadily or it stabilizes, but with maybe a sharp drop-off at the end just before the parent bird kicks the bucket. For a real-world example, there was this 21-year study of blue-footed boobies

in a breeding colony on a small island off the west coast of Mexico. This paper was published in 2011 in the journal PLOS 1. The researchers found that, the survival of young boobies is highest when they're raised by parents that are between six and 12 years old. Younger and older parents are less successful at raising chicks. The line plotted on the graph for these blue-footed boobies in Mexico has the shape of an arch, or an upside-down you, pretty much like what I described earlier, the typical shape for many birds. But some other long-lived birds show a different pattern. The snow petrel, pagodroma, nivia, is a beautiful white

sea bird that breeds in Antarctica. Hard to believe, but yes, there are actually a few other birds in Antarctica besides penguins. A snow petrel can live for 45 years in the wild. The likelihood of successfully raising chicks in this species increases from age six to about 12. But unlike blue-footed boobies, snow petrels have been shown to keep on cranking out and successfully raising one baby every year pretty much until they die. They just have one chick at a time. So why might older birds have this peak in their performance when it comes to raising chicks? Some possibilities are that, one, birds in their prime have mastered their nesting and foraging skills. Two, they may have relatively low stress levels, and three, they may have the highest level of disease resistance.

Yes, it does seem like the effects of a parent's age on reproductive success can be more significant for bird species that live a long time. Short-lived birds may have only a few years to breed, or even just one year. They don't really have the luxury or even the opportunity to get better at raising a brood. Lastly, Emily asked about how this all plays out with social species. In my search of the scientific literature, I couldn't find studies that specifically addressed the effects of the sociality variable on the relationship between a parent's age and the survival of its offspring. In other words, does that relationship change when you're talking about a very social species versus a species that is not social

at all? I couldn't find any research on that. In any case, the research does tell us that Fledglings in many social species seem to have higher chances of survival than in non-social species, especially in cooperatively breeding species. In cooperative breeding, the chicks are often raised by not just mom and dad, but also by older siblings and other relatives. Our second breeding-related question comes from Eric. He recently observed a female American Robin searching for her wayward fledgling. Eric asks, quote, How often do bird parents lose track of their fledglings and at what point do they give up looking for them? Also, how are adults able to keep track of fledglings in busy cities when they

can't hear their calls? End quote. Eric's first question is so good that I think someone needs to conduct some research to answer it. Research on how long it takes. Research on how long it takes a parent bird to give up searching for a lost fledgling. I assume the duration would vary a lot among species, but who knows? Someone needs to do this research because I could not find an answer to that question. Maybe it's out there, but I just could not find it. I'm trying to imagine what those experiments would look like, though. A researcher in a lab removes a fledgling from its parents, then records the parent's behavior. How long does it take the parent to go from, Where's my baby? Has anyone seen my baby? My sweet baby is missing. To go from that to

Now, what was I looking for? Was it my car keys, my phone? Hmm. Well, whatever it was, I guess it wasn't that important. In any case, post-fledging parental care is an important part of the life history for most birds. The effort of care and the duration of care vary a lot from one species to another. One of the key requirements of post-fledging care is parent-offspring recognition. A young bird needs to be able to recognize its parents and vice versa. This is often accomplished with vocal communication. Sometimes birds use special calls just for the purpose of communicating with their chicks or in the case of fledglings with their parents. The second part of Eric's question was, how are adults able to keep track of fledglings in busy cities when they can't hear their calls. It seems likely that adult birds would

have a harder time keeping track of their rambunctious fledglings in urban environments. There is, thankfully, plenty of research on the effects of urban noise on the behavior and ecology of birds. Maybe not specifically about losing your fledglings, but I'll give you one example. There's a paper titled, When Ambient Noise Impairs Parent Offspring Communication. It was published in 20, 2016 in the journal Environmental Pollution. This study, conducted in Belgium, looked at parent-offspring communication in the blue tit, cyanoste's ceruleus. The researchers used previously recorded traffic noise and plated near the nest boxes of blue tits in the experiment.

Now, this study was using nestlings and not fledglings, but it still seems relevant to Eric's question. The result was that parent birds feed their chicks at a lower rate of the rest. See, it's hard to hear anything over that obnoxious traffic, isn't it? Kind of illustrates the point. Because what I was saying is that this study showed that parent birds feed their chicks at a lower rate at the nest when there's loud traffic noise nearby. The explanation for this behavior offered by the researchers is that with loud traffic noise, the chicks in the nest had a hard time hearing their parents returning. to the nest. If the chicks didn't hear their parents, they didn't beg for food. Without the

stimulus of screaming begging chicks, the parents were less likely to bring the little guy's food. So yeah, city life can be hard, for many reasons, including making it harder to talk to your kids or to get your parents to give you food. Candy asks us another question about breeding, specifically about the morning dove, Zanida Macroura. Candy's question is, quote, why do morning doves throw like two sticks and a rock in a pile for a nest and call it good? Other birds are painstakingly building intricate nests, but these guys just put in very little effort. And they often nest in what seem to be horrible places for a nest.

Yet they must have success because their species numbers are doing quite well. End quote. Indeed, morning doves are doing pretty well. This is one of the most familiar and common birds in North America. And indeed, morning doves make flimsy little nests out of pine needles, twigs, and grass. There's no lining or softer material for comfort or insulation. A morning dove nest would probably fail miserably in any building code inspection. As Candy points out, these doves build their rickety nests in all sorts of odd places,

in rain gutters, on lamp posts, on a shelf in someone's garage on top of a coiled-up extension cord, and so on. You can find morning dove nests on the ground and all the way up to a hundred feet or more in a tree. Flimsy platform nests are not unique to morning doves. This is actually a common feature for birds in the family, Columbadie. I talked about all of this in episode 32 of the podcast, which was about this avian family. Now, I can't answer the question of why doves build nests like this. But one rule in nature is that whatever works, with the minimal amount of effort and risk is good enough, the path of least resistance. As long as birds can survive long enough

and leave behind a few offspring, that's good enough. Morning dove nests probably wouldn't work very well for many other kinds of birds, but they do the job for the doves who build them. The morning dove is one of those species with a short lifespan. The expected lifespan of a morning dove is just one year. That's right, they live for one year on average. So, like we were talking about earlier, these birds don't have a lot of time to perfect their nest building skills over years and years. They just throw together a pile of twigs and grass in an old bucket or on top of a mailbox or wherever, and that'll do. But I should point out that morning doves compensate for their short lifespans by breeding more than once in a year. A monogamous,

must pair sticks together for the long breeding season, often reusing their same flimsy nest to raise multiple broods. Tracy asks the next question, which has to do with bird behavior. Quote, when it rains, many worms come out onto my neighbor's paved driveway. Yet I don't see robins or other birds taking advantage of this buffet. Why don't worm-eating birds gorge themselves on this bonanza? The worms are right out in the open, no digging needed. End quote.

We've all seen this phenomenon, right? It's been raining heavily for a while, and then the wet sidewalks, roads, and driveways are literally crawling with worms. But before we talk about the bird's behavior, let's look at the worms. Why do they do this? Why would they come to the surface and put themselves in danger by crawling around? out in the open. People have scratched their heads and hypothesized about this for ages. The standard old answer was that when it rains, the soil where worms live gets saturated with

water. Worms can absorb oxygen through their skin, so they don't necessarily need air, but oxygen diffuses much slower through water than through air. So the worms come to the surface to avoid drowning or suffocation. That's the old answer. And, there's probably some truth to it. But another, perhaps complementary explanation, is that some worm species leave the safety of the soil so that they can move around more easily. It's much easier for a worm to cover distance on the surface compared to pushing its way through dirt.

Some worm species naturally migrate in search of mates or new territory. But coming to the surface on a sunny, dry day would spell doom for them, since they would quickly dehydrate and shrivel up. A rainy day or night, on the other hand, is the perfect time to move around on the surface. Except for when the birds show up. But Tracy is pointing out that birds in her neighborhood anyway don't seem to be taking the bait. They don't seem to take advantage of the easy pickings. And that's been my experience too. I have not witnessed birds swooping in to gorge on the rainy day worm buffet. So what did I do? I turned to YouTube. to see if anybody else has documented this behavior.

And sure enough, I came across multiple videos of people watching flocks of birds gobbling up worms after it rained. So I guess maybe if we spent enough time systematically looking for this behavior, like undertaking a scientific study, we might find it to be more common than we realized. My anecdotal experience is similar to Tracy's, but I'd have to see some hardcore scientific data before I'd say that birds are actually being foolish, that they're truly missing out on great opportunities to slurp up mouthfuls of wriggling worms.

All right, we're moving along here. The next four questions all have to do with bird anatomy in one way or another. The first comes from Catherine. She asks, quote, I understand birds see a wider range of color than humans, due to having four receptors rather than hour three. Do birds hear songs and calls with a wider sense or ability to receive sound in a similar way as sight perception? End quote. Excellent question, Catherine. Hearing in birds is most sensitive to sounds with frequencies between roughly one and five kilohertz. Sensitivity

above or below that range drops off, and the range, of course, varies among species. This range of frequencies and the peak of hearing sensitivity in birds are, perhaps surprisingly, similar to those of humans. So their hearing isn't all that different. But there is one key difference. Birds have the superpower of being able to tease apart the minute differences in frequencies over very short time intervals. Their hearing is more discerning than ours on the axis of time. Let's say you hear this complex song from a Pacific Wren that I'm about to play for you. You can hear all the frequencies and you can tell there's a lot going on in there, but it's a bit of a jumble. To another bird, another Pacific Wren, we can imagine that that bird

would hear that song something like this. That was the same song, I just slowed it down a bit. The wiring in bird brains that's related to hearing allows them to detect and understand frequency changes that, for us, happen so fast that they sort of blur together. On a related topic, Sam has a question about some unusual members of the Blackbird family. Sam's question is, how do oropendulas make their crazy, bubbly noises? Oh, you mean like this, Sam? Those crazy bubbly noises were the songs of some Montezuma Oropendulas, Saracolius Montezuma, recorded in Costa Rica.

Oripendula is spelled Oro P-E-N-D-O-L-A. There are nine Oropendala species, all in the genus Saracolius. Imagine a very large blackbird with a super-sized, super-thick, pointy bill. In some species, the bill extends on to the bird's forehead, forming a frontal shield. Some oropendala species are mostly green, some mostly black, and some, like the Montezuma orapendala, are mostly a chestnut brown color. The latter species has a two-toned bill, like a black bill that was dipped in orange-red paint. There's also some colorful bare skin on the bird's face, in blue, white, and pink. Oripendulas, in general, we are

large hanging nests and they breed in colonies. Apparently, male Montezuma oropendulas all sing pretty much the same song, with little variation among individuals. The song is thought to be used as a means of communication at close range within the colony. This differs from the function of singing in many other bird species, which use song to broadcast information over greater distances. One researcher described the song of the Montezuma oropendola as, quote, A liquid gurgle, an undulatory sound ascending in pitch. When heard in the distance, it is most melodious. But when the performer is nearby, his screeching overtones somewhat mar the effect.

End quote. Listen again to these monizuma orupendalas singing. Do they sound most melodious to you? Do you hear any screeching overtones? Ooh, there's another possible band name to add to my list, The Screeching Overtones. Okay, here's the recording again. As he sings his song, the male or a pendula makes his bow display.

As he makes his undulatory song, he raises his yellow tail and falls forward on his perch. At the end, it looks like he's going to fall face forward off the bird. ranch, and he saves himself just in time. I'll put a link in the show notes to a video of this bird singing and making his bow display. It's pretty cool. Sam, who asked this question about oropendulas, is probably like, yeah, yeah, Ivan, I know all that, but my question is how do these birds make their crazy noises? Right. So I couldn't find any research specifically on the vocal anatomy of oropendulas. But since these are songbirds, we know that they have a syrinx, S-Y-R-I-N-X. This is the sound-producing organ that sits where a songbird's trachea splits into

the two tubes called bronchae that lead to the lungs. Each half of a songbird's syrinx can make sound independently. The bird controls the fine muscles of the syrinx with its brain and nervous system to make amazing complex sounds, often two different sounds at the same time, layered together. I suspect that oropendulas make good use of that particular superpower, the ability to combine two sounds into one crazy bubbling song. We're on a roll with a topic of bird songs here, because our next question also has to do with bird vocalizations. Liz, who lives in Australia, says, quote,

Hey, Ivan, I'm just wondering why magpies have so many different sounds. We have heaps in our backyard in Brisbane. Sometimes they have a beautiful cooing song, but they also have lots of other calls. Do you know what they are all for? End quote. The Australian magpie, Jim Norina Tibison, is in the family Artamadie. Though this bird looks somewhat like an American or European magpie, it's not a close relative of those birds, which are in the family Corvody.

In case you've never heard an Australian magpie, here's an example of its strange, flute-like, cooing or gurgling song. These are intelligent, social birds. Listening to each other's vocal sounds, they can tell whether a bird is a member of their own breeding group or an outsider. And if it turns out you're an outsider, uh-oh, you better look out, buddy,

because Australian magpies are highly territorial and they're going to attack you. As for their songs, yes, this species, has a repertoire of many vocal sounds. Researchers have figured out the purposes of some, but not all of these. The most famous is the caroling song. That's spelled C-A-R-O-L-I-N-G, caroling. But the British spelling has two L's.

Imagine the sound I played for you a moment ago. That's more or less a caroling song. Multiple individuals often make this caroling song together. The dominant male or female in the group gets it started, then everybody else joins the chorus, like a bunch of people singing Christmas carols. And like Christmas carols, the function of caroling in magpies

is for the group to announce itself and aggressively defend its territory. I mean, that's what I do Christmas carols for. I go out and I defend my territory. I just sing super loud, so nobody messes with me. Anyway, magpies also carol when they discover an exciting bounty of food. This species eats mostly insects

and small vertebrates like, lizards and frogs. So that's caroling. Then there are some softer warbling songs. For example, during the breeding season, a magpie might sing the dusk song, the dawn song, or the moonlight song. The moonlight song is, of course, the most romantic of the three. Perched on a balcony and wearing a flowing ball gown, an Australian magpie looks longingly into the night sky, singing about true love. and defying societal expectations. But seriously, the Australian magpie really does have a moonlight song,

that it sings on moonlit nights. Again, this is during the breeding season, and the singers are likely to be males. Then there are many kinds of alarm calls. These would be to warn others in the group of any lurking danger, like a snake or other predator. Now, I'm not sure, but I wouldn't be surprised if they have different alarm calls for different kinds of predators, snakes versus hawks, for

example. The rally call, which has been described as, quote, a loud descending whistle of two or three syllables, magpies can hear their buddies making this call from far away. As its name suggests, the function of the rally call is to summon the members of a group. It's kind of like, Magpies assemble! This is usually in response to a predator attack, or, territorial dispute with another group. And then, of course, there are some begging calls made by nestlings and fledglings. Australian magpies are also good at mimicking the sounds of other bird species and other animals. They even mimic artificial sounds like emergency sirens. So I hope that sheds a little light on the functions of all the many magpie calls. Ornithologists are still trying

to decipher their meanings, so there's still a lot to learn. Our next question comes from Dan. This does not have to do with songs or vocalizations. Well, actually, I guess it sort of does. Dan says, quote, Walking through the woods in the spring, there's all kinds of pollen in the air. While I'm looking for warblers, I've definitely sneezed.

But come to think of it, I've never heard a bird sneeze or cough. Is this a thing? The birds must get particles from the air caught in their windpipe sometimes, just like we do. How do birds deal with this? End quote. Good question, Dan. Yeah, my allergies have been terrible this year. It sucks because at exactly the time when the bird activity is at its peak, when the birding is as good as it gets around here, that's the time of year when my stupid allergies kick into high gear. Anyway, as Dan points out, birds must occasionally inhale small particles and they need to expel those particles from their respiratory systems. And indeed, birds do sneeze. I've had pet chickens and have watched them sneeze on many occasions. They close their eyes and

often shake their heads as they sneeze. The sneeze clears particles from the nasal passages. But just to make sure that this isn't just a chicken thing, that it's more universal, among birds, I turned once again to YouTube. And sure enough, I found some videos of various kinds of birds, including songbirds, sneezing. As for coughing, this is interesting, because in humans, our diaphragm muscle contracts forcefully when we cough. But birds don't have a diaphragm. Nevertheless, they do cough if they have an infection or if something irritates their respiratory system. But a bird cough sounds more like a chirping sound rather than a human cough. But let's keep in mind that there are major anatomical differences between birds and humans. Birds might have reflexes

that have the same end result as our sneezes and coughs do, but the underlying mechanisms might be different. In any case, if you haven't heard birds sneezing or coughing yet, maybe it's just a matter of time. Get yourself some pet chickens. Or disguise yourself as an oversized blue-footed boobie and sit in the middle of a teeming seabird colony all day every day for several months. I bet you'll hear some sneezes. Eventually. We have just a couple more questions to answer. And I'd say these are in the miscellaneous category. First up is a question from Katie. She asks, quote, how do I tell crows apart from ravens? We have tremendous flocks here in the Coachella Valley in California and in the surrounding

mountains, end quote. Ah, yes, this is the age-old challenge, a question that many of us have asked. How do you know whether that black bird you're looking at is a crow or a raven? Katie lives in California, so for her we'd be talking about the American crow, Corvus Bracharinkos, versus the common raven. Corvus Corax First, there's the size difference. A raven is about twice as big as a crow.

But unless you can see them side by side or you have some other object to use for comparison, size isn't the best way to tell the two birds apart. But we can always look at the relative sizes of the bill. The specific epithet of the American crow's scientific name, Brachorincos, is actually Greek for short bill. The common raven's bill is thicker. It's usually as long or longer than the bird's head. The raven's bill has longer bristle feathers at the base, and it has a more distinct hook at the tip.

You can also tell these species apart when they fly overhead in a couple of ways. American crows tend to flap frequently. They rarely soar. Ravens, on the other hand, spend a lot more time soaring. A raven's wings make a whooshing sound in flight. So if you hear that, you've got a raven, but you will not hear that when a crow flies by. Another thing to look at when these birds are flying is the shape of the tail. The American crow has a rounded off, or a blunt-looking tail. A common raven's tail, on the other hand, is diamond or wedge-shaped. That's because the central tail feathers of the raven are longer than the outer feathers.

And you can often tell these birds apart by their voices. Common ravens and American crows make distinct sounds. Crows make the classic caw-ca sound, like this. Raven calls are somewhat similar, but they're lower-pitched. Ravens croak rather than caw. Here are some ravens calling. Ravens make a bunch of other vocalizations, too. Some of them sound like human screams or like chimpanzee-quoise.

calls. Recognizing the differences between crows and ravens can be challenging, even when you know what to look and listen for. So just know that you are not alone, Katie. This is a classic ID challenge for many bird lovers. All right, I've got just one last question here. Janice says, I'd love to know your top picks for amazing birding spots. Where is the most? most interesting bird population. Cool. This one will be fun. I don't need to do any research to find the answer. I just need to sift through my own thoughts and my happy memories about birding. There are still many places in North America and the rest of the world where I have not gone birding. That said, I've been

around a little bit. I work as a guide for the birding tour company I co-own, Wild Latitudes. That work has given me many wonderful opportunities to see birds around the world. Just thinking about the U.S., I'd have to say my favorite birding destination is Southeast Arizona. And this is a well-known birding hotspot. It's a combination of desert, mountain, and riparian habitats that bring together many interesting bird species into a relatively small geographic area. And Southeast Arizona is also where several major ecoregions come together. It's one of those places in the U.S. with birds that are otherwise found

only south of the border, in Mexico and beyond. We're talking species like elegant trogon, Mexican J, rose-throated beckered, monizuma quail, olive warbler, and maybe one of my favorites, the red-faced warbler. Also, Southeast Arizona is the number one hummingbird hotspot in the U.S. You can find about 15 species there, including Rivoli's hummingbird, Lucifer hummingbird, Broadbilled Hummingbird, and the blue-throated mountain gem. As for other countries where I've had amazing birding experiences, I'd have to say the top of the list includes Australia, Uganda, Ecuador, and Spain. Those are places I've been to more than once and that I hope to return to someday. And there you have it. We did it. That wraps up the

latest Ask Me Anything podcast episode. Thank you so much to all of my Patreon members who offered questions. You guys came up with some really good ones. I hope I appeased your curiosity and thirst for bird knowledge, at least for a little while. This is, or that was, episode 96 of the Science of Birds podcast. We're seriously closing in on 100, you guys. I hope you enjoyed listening to this question and answer style episode. There's a support the show link in the show notes if you would like to become a Patreon member, so you can contribute questions for future episodes like this. And thanks to my entire Patreon community, you guys rock. There's a community chat feature now on my Patreon page, and it's been really fun to interact with you guys there. My newest members are

Julius the Burb Nurb, Steph Stout, and Galadriel. Welcome to all of you, and thank you very much for the generous support. Any of my listeners can shoot me an evening. email if they have something to share with me. Perhaps you have some kind words about the podcast, or you want to tell me all the ways that you, much like a love-struck Australian magpie, defy societal expectations. In any case, my email address is Ivan at scienceofbirds.com. I'm often slow to respond to email. That's just how it is, but I try to get back to everyone. You can check out the show notes for today's episode on the Science of Birds website, scienceofbirds.com. And don't forget that I've got a little shop on the website where you can

order some fun Science of Birds merch like official logo t-shirts, posters, and stickers. This is Ivan Philipson. I hope you're having and we'll continue to have a great day. Peace.