The Science of Birds - Random Bird Thursday: A Worm-slurping Mud-runner From Siberia

Episode Date: December 12, 2025

In each Random Bird Thursday (RBT) episode, the goal is to highlight a bird species that probably isn't going to get featured in a full-length podcast episode. These are birds we might overlook, even though they certainly deserve some appreciation and attention. ~~~~~~~~~~~~~~~~~⚠️ SPOILER ALERT!The featured species in this episode is the Asian Dowitcher (Limnodromus semipalmatus)Asian Dowitcher sounds (Xeno Canto recordings XC349045 and XC806613)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. And lucky us, it's Random Bird Thursday. Random Bird Thursday episodes are relatively short and sweet. In each of them, I spotlight a bird species that probably won't get featured in a full-length episode. There are over 11,000 bird species in the world, so Random Bird Thursday gives us a chance to celebrate a species that we might otherwise overlook.

Now, I've had some questions recently, and I think there's a little bit of confusion. Some people think I actually choose these birds, but I don't. It's really random. I literally have a button on my desk that I push, and it pulls up one of those 11,000-plus bird species, and that's the bird we have for the episode. Now, that said, I do sometimes choose to veto whatever bird pops up, because either I've already talked about it,

or it's a bird species I think is worthy of an entire full-length podcast episode, because there's just a lot to say about it, or there's just so little information about the species that it would be kind of hard to make a random bird Thursday episode about it. So yes, random bird Thursday is truly, definitely random. And that's the fun. That's why I think it's really cool, because I have no idea what bird I'm going to talk about until I do.

And I have no shame in admitting that I have to research these birds. It's not like I know the bird, all of the ins and outs of the species, when it first pops up. But that again is part of the fun. I like learning about these random birds from around the world, right alongside you, and then I add in whatever knowledge I already have about all the things.

So without further ado, let's go ahead and push the random bird selector button, the actual button, and see who we're talking about today. Okay, we have a shorebird. We have the Asian Dowager, Lymnodromis semipalmatis. Everybody loves a shorebird, so let's go ahead and get right into it. The Asian Dowager, true to its name, is an Asian bird, at least where it breeds. It has four disjunct or sort of separate breeding populations in northern Asia.

The westernmost patch of the range is north of Kazakhstan, and then you've got a gap as you move east, and then you've got Mongolia and into Siberia and Russia, and then there's another patch in northern China, sort of two patches in northern China and southern Russia. So that's the breeding range. In the winter, in the non-breeding season, these birds move south into India, into Southeast Asia, the Malay Archipelago, the Philippines, and Australia.

The Asian Dowwitcher is a gregarious species, so quite social. They're typically found either in pears or small flocks. Even sometimes larger flocks, over 100 birds, will gather at their roosting sites or their favorite feeding sites. And that would be more common in the non-breeding season. Okay, but what does this bird look like? Well, if you're just looking at the body shape, it has a pretty typical sandpiper body shape, but it's a medium-large size for a sandpiper, about 13 to 14 inches long from beak to tail, which is 33 to 36 centimeters.

Now, of the dowwitchers, this is the largest species. There are three species of dowager. But if you were to see this bird in the field, the Asian dowwitcher, you might confuse it with the bar-tailed godwit. These two species look fairly similar, superficially. The Asian dowager is a little smaller. But the bill shape is key. That's what's different.

The Asian dowager has a long bill, but it has a bit of a blunt tip at the end. Whereas the bar-tailed godwit, like other godwits, has a bill that tapers to a relatively sharp point, and in the godwit the bill curves up slightly. Whereas in the dowager, it's really straight. Now, you may have heard of the long-billed and short-billed dowwitchers, and even though the Asian dowager is larger than those other two species,

its bill is not quite as long as the long-billed dowager. The Asian dowager is quite lovely in its breeding plumage. The overall look is pretty brown, but very kind of rust and reddish-brown, especially underneath where it's more reddish. And it also has some blackish upper parts with some paler brown and chestnut color, so that it has kind of a streaky look on the back. Now, compared to the short-build and long-billed dowatures, the Asian dowager has relatively few dark markings on its neck and on its breast.

And in the Asian dowager, the female is generally more dull than the male, and she has a bit more white. So there is a bit of dichromatism in the sexes for this species. Now, that was all in the breeding season. In the non-breeding season, which is probably when most people would see these birds, The overall plumage effect is gray, like many other shorebirds, or sandpipers. The adults have a pale supercilium, right? So that's that eyebrow line, and they have darkish gray-brown upper parts and whitish underparts.

The tail has a black-and-white barred pattern, and the rump is barred. And the legs are dark color. They're a dark gray. So now let's talk about how these birds sound. On their breeding territories, the males give a kind of a pur-call, a booming pur-call it's described as. They'll do that in the air and on the ground, and these kind of pulses of purring calls. So I do have a recording for you, and I think this is probably an example of those purring calls mixed in with some other sounds. This recording was made in Mongolia.

When Asian dowwitchers are in their non-breeding habitats, they don't really make a lot of sound. But occasionally they make this kind of cat-like meow sound, more often in flight. And I think this next recording, which was made in Taiwan, is probably an example of that meow call. Now let's talk about the scientific name, Limnodromus semi-palmatus. This species was originally described in the mid-1800s. So Limnodromis, that's the same genus for all three dowagers. This comes from ancient Greek, and the two words together mean marsh-werews.

runner, limno-dromis. So this suggests a bird that kind of runs around in swampy or muddy areas, which is exactly what these birds do. So that's limno-dromis, the genus, and then the specific epithet, the second part, semi-palmatis, is from Latin, and that translates as partially webbed, semi-palmate, referring to the feet. And that pops up in other species, right? So like the semi-palmated plover. The Asian dowager is a sandpiper in the broad sense, meaning it's in the family scolopacity, or scolopacity, which we went into in detail in episode 26 of the podcast. So again, there are three species in the genus Limnodromas, the Asian dowwiture, short-billed, and long-billed dowwitchers. The latter two are probably much more familiar to birders in the Western Hemisphere,

Because both species breed in North America, the long build breeds way up in the Arctic, in Alaska, and Canada, whereas the short build breeds a bit further south in Canada and Alaska. The short build spends the winter in the southern U.S., in the Caribbean, Mexico, Central America, and South America. The long-billed dowager spends its winter in the southern U.S. as well, but also Jamaica, Mexico, and a few little places in Central America. So maybe you've seen one of those species, if not the Asian dowager. But again, the Asian dowager is distinctly larger and it has fewer dark markings on its neck and breast. Now, once upon a time, I'm not sure which time, but a while back this species, the Asian dowager was treated as being in its own genus, pseudoscolopax, pseudoscolopax. And that translates as false woodcock, because,

the woodcock or the woodcocks are in the genus Scolopax. So ornithologists at one point believed the Asian dowager was an imposter, that it was a pseudo-woodcock or a false woodcock, but that has been revised. There aren't any subspecies within this Asian dowager, but there are geographical separations between the western and eastern breeding populations. They have different migration routes, and they winter in different areas, so there's a good chance that those are actually subspecies, meaning that they're on independent evolutionary trajectories that might result in distinct species someday that can't interbreed. As for habitat, when these birds

are in their breeding range in the north, they're going to spend time in extensive freshwater wetlands on the shores of lakes, maybe in the deltas or flooded river areas, and even in flooded meadows and bogs. They like places with some short grass and sedges. But in the non-breeding season and during migration, they're going to spend more time in sheltered coastal environments, primarily in intertidal mud flats, which are in estuarine areas, tidal creeks, muddy lagoons, and they'll spend time in human-made environments like saltworks. And as I mentioned, this is a gregarious species that socializes with its own kind, but also Asian dowwitures will hang out. with other shorebirds, particularly godwits.

They'll all kind of loaf around on sandy beaches or in shallow lagoes together. And that's primarily true in the non-breeding season when they're in places like Southeast Asia, India, the Malay Archipelago, and so on. This is a strongly migratory species. As I mentioned, they're going to use two different flyways, depending on the population. One population uses the East Asian Australasian flyway, and the other one uses the Central Asian flyway. Some of these birds have been tracked as they're heading south out of Mongolia and the average duration of their migration was about 47 days. But if I understand this

correctly, of that time, about 31 days were rest periods. So the birds can cover a lot of ground or cover a lot of air in a relatively short amount of time. The average flight speed is about 32 miles per hour or 53 kilometers per hour. Though apparently, speeds of up to about 90 miles per hour have been recorded, which is 144 kilometers per hour, probably with a tailwind. But yeah, these birds are fast-flying, long-distance migrants. Now, they're going to fly along the coast primarily. A lot of the movement is along the Southeast Asian coast.

Perhaps the most important stopover sight for this entire species is the coastal wetlands in Jiangsu province of China, the wetlands of Liangyang, if I pronounce that right, which I probably didn't. And at least during the northern migration, about 90% of the estimated total population for the species stops by these wetlands. And that leads us into the topic of conservation. This species is currently assessed as being in the near threatened category by the IUCN. The estimated global population is maybe something like 20,000 to 25,000 birds. The species is really susceptible to disturbances by people, by humans.

And that's particularly because of these migratory stopover sites. The birds become really concentrated in small areas, as I mentioned, in the wetlands in China. So anything that happens to those wetlands or those stopover sites can dramatically impact the global population or a large portion of it. So, for example, in the Liangyang wetlands in China, there's been habitat loss, with development projects like tourist facilities, as well as shellfish farming, which is in conflict with the birds' habitat. So, yeah, there's a lot of threats primarily

to the migratory wetlands that these birds depend on. Climate instability can cause problems anywhere in the birds' range. For example, when they're breeding, their nests might fail because of flooding. And in the breeding habitat, human activities can be a problem as well. For example, the nests are sometimes trampled by cattle. Okay, well, before we move on to talk about what and how these birds eat,

I just want to mention a couple ways that you can support the work I'm doing here with the science of birds. First off, there's Patreon. I have a growing community of supporters on Patreon who make monthly contributions that make it possible for me to make these episodes for you and everybody else. It's really an amazing thing. So if you're interested in Patreon, you can check out patreon.com slash science of birds. And another thing you can do to provide support for the podcast is go to birdmerch.com. That's the online store that I've created, where I've got a bunch of bird and birding themed t-shirts that I've designed.

And so you can get yourself some shirts, support me in the show, and everybody's happy. Again, that's birdmerch.com. Okay, Asian dowwitchers. What do they eat? So in their breeding habitat, they're going to eat small fish, insect larvae, and certain kinds of worms, particularly oligate worms. And if you don't know your different types of worms, that's okay. Just know there are different kinds. It's not all just earthworms everywhere.

They come in lots of different varieties, and oligate worms, that's one type. Asian dowretures will also eat some small crustaceans and maybe even some plant material. In their non-breeding habitats, their primary diet is going to be polychaet worms. See, there's another one, as well as insect larvae and mollusks. So how do these birds find these things and eat them? So limnoidromis means marsh runner, right? So they're walking around on damp ground or in shallow water, kind of moving methodically, and they're repeatedly probing the mud with their long straight bills.

And if they're in the water, sometimes their head gets fully submerged. And the repeated probing, that's the key thing with these guys. Because their head is going to move up and down, up and down, up and down, in what is described as a sewing machine-like action. Now, I think if you have a modern sewing machine, then this analogy doesn't work quite as well. But if you lived in the 1800s, you would know that the old wooden sewing machines have this kind of up-and-down action that's very obvious.

because as is so popular with all the kids today sewing is a very popular hobby especially using the sewing machines from the 1800s back to basics and i mean these sewing machines are the ones that are powered by your feet you have to like pump a pedal and that's what makes the thing spin and makes the thing go up and down it's really cool if you've ever seen one but uh yeah and so the birds are walking along they're doing this probing and they'll will they will detect something down in the mud they can feel it and if it is a worm they might have to yank and tug and pull on it for quite a while

before finally getting the worm out of its burrow or whatever and the birds will be moving along on a mud flat and they'll follow the tide so as the tide is receding they'll move out and then they'll move back in but back to the sewing machine we're not done with the sewing machine okay so the bird is called a dowitzer right i have not explained where that name came from So a dowager is, according to the dictionary, a widow with a title or property derived from her late husband. Okay, so a widow, they got money or a title like a duchess or something from her late husband. And more informally, we might say a dignified elderly woman is a dowager.

But you might already be screaming at your phone or whatever you're listening to this on. If you have a better command of the English language than I do, you know that dowager and Dowwitcher are two different things. Dowager, the bird, is spelled D-O-W-I-T-C-H-E-R. Dowager, the dignified elderly woman, is spelled D-O-W-A-G-E-R. But your host, Ivan Philipson, did not know that these things were unrelated until now. For you see, I thought that because the foraging behavior of these birds was described as being like a sewing machine, that somehow that was like, oh, yeah, that's what dowagers do, these dignified

elderly women that are widows sit around and sew all day using sewing machines from the 1800s. I realized how foolish I was and how ignorant when I opened up the bird name book by Susan Myers. Under the entry Dowager, I discovered that there's no relationship to Dowager, different spelling. so in fact dowager the bird we don't know where that name came from it has nothing to do with elderly women it could be one hypothesis is that dowager came from a native american language specifically the iroquois people who had a name for snipe which was tawistawis tawistawis so maybe english speakers came along heard that and somehow it evolved and degenerated into dowwitcher Or the other hypothesis is that Dowager's origin is in the German language. Because apparently the word for snipe in German, at least one version of German, I'm not sure if this is still true, is Deutsche? D-E-U-T-S-C-H-E-R, Deutsche?

Dowager, Deutsche, maybe. So who knows? But I was wrong, and I'm happy about that. It was actually really exciting to learn that these two words are spelled differently. and yeah, so we're all learning. Moving on. Let's talk about breeding. These birds are probably monogamous,

although I couldn't find any specific references that said that they are definitively monogamous. In any case, both parents do participate in the incubation and taking care of the chicks. The nest is a shallow depression, either on bare ground or in vegetation with some sparse grass. The nest is lined with grass. and if it's in a wet area it might be built up above the water line a little bit, a few

inches perhaps. The pair of Asian dowwitchers establish a territory around their nest site and they defend it. The clutch size is typically just two eggs, but occasionally three. And the pair will almost always raise just a single brood per season. They're going to incubate the eggs for about 22 days, so about three weeks. The baby's hatch, their parents continue to take care of them for some time. And the only other thing I could find was that the Asian Dowager probably doesn't breed for the first time until it's about three years old.

So I didn't say it earlier, but really this is a species that we don't know a whole lot about. There are definitely some gaps in our knowledge, particularly when it comes to breeding. But so it goes. And I have not seen this bird yet. I would like to. It looks really lovely, especially in its breeding plumage. I really do like shorebirds. I think they're great in general. I did have an opportunity to see this bird. I was in its breeding habitat

at the right time of year. I was in Mongolia earlier this year, and I just happened to not see this species. I'm going back to Mongolia next year, so I will definitely be keeping an eye out for the Asian Dowager. Limnodromus semi-palmatis. How about you? Have you seen this bird? Let me know. Send me an email, Ivan at Scienceofbirds.com. And with that, my friends, we conclude this edition of Random Bird Thursday. Thanks so much for being here, for listening, for loving birds, and wanting to learn about birds. And I'll catch you next time.

Cheers.