Ologies with Alie Ward - Strigiformology (OWLS) Part 1 with R.J. Gutiérrez

Episode Date: November 5, 2025

OWLS. FINALLY. In no particular order: what’s up with their eyes, legs, hoots, feathers, silent flight, nests, folklore, necks, barfs, conservation status, and omens? Go take a walk or sit on a porch in the dusk and make friends with Rocky. Dr. R.J. “Rocky” Gutiérrez is a celebrated researcher, Professor Emeritus at the University of Minnesota, a legend in the owl world, and simply one of the loveliest ologists. He’ll take us on a trip next to a river, scrambling up some trees, over rocky terrain and through the forest to learn why owls are so magnetic. Yeah, I called owls the best bird. Not backing down. Follow Dr. Gutiérrez on Google ScholarDonations went to the International Owl Center and Northcoast Environmental CenterMore episode sources and linksOther episodes you may enjoy: Ornithology (BIRDS), FIELD TRIP: Birds of Prey and Raptor Facts, Condorology (CONDORS & VULTURES), Plumology (FEATHERS), Corvid Thanatology (CROW FUNERALS), Chickenology (HENS & ROOSTERS), Columbidology (PIGEONS? YES), Ophthalmology (EYES), Lutrinology (OTTERS), Lemurology (LEMURS), Procyonology (RACCOONS), Opossumology (O/POSSUMS), Scatology (POOP)400+ Ologies episodes sorted by topicSmologies (short, classroom-safe) episodesSponsors of OlogiesTranscripts and bleeped episodesBecome a patron of Ologies for as little as a buck a monthOlogiesMerch.com has hats, shirts, hoodies, totes!Follow Ologies on Instagram and BlueskyFollow Alie Ward on Instagram and TikTokEditing by Mercedes Maitland of Maitland Audio Productions and Jake ChaffeeManaging Director: Susan HaleScheduling Producer: Noel DilworthTranscripts by Aveline Malek Website by Kelly R. DwyerTheme song by Nick Thorburn Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

Oh, hey, it's the guy who runs the local board game night, hoping someone shows up at the pizza place to game. Ali Ward, boy, hooty, I've wanted to cover this one forever. And it was all a matter of finding the right owl person. And we did it. We got them. I have so much to say about this guest that I'm going to list it in bullet points. Okay, so they got their PhD at the University of California, Berkeley. They have studied owls for over four decades. Their papers have been cited nearly 14,000 times. I noticed that in their papers, they thank their wife, KT. and they seem genuinely in love. They came highly recommended by several other ologists, including Dr. Gavin Jones of the Fire Ecology episode. I had to beg this owl guest to be on this episode because they kept asking if they were right for it. I did this by taking a phone call as I was driving through the desert

and I pulled over at a dusty turnout to chat with them for like 30 minutes about why I was already obsessed with them and their work. Before we recorded, this guest sent me some pictures and owl videos, but there was nothing attached to the evening. email, and then I got another one five minutes later with the subject line, oops, and the email just said, I got distracted by critters outside my window, so I forgot to attach the files. When we finally did log on to chat, they were wearing a sweater with owls on it. Uh-oh, I love them, and you will too. It's all the fieldwork stories and passion of a Merlin Tuttle back guy with the soothing

mellow vibe of the Briology Moss guest, Dr. Robin Wall Kimmer. This one, it's an instant classic. We will get to that in just a sec, but first thank you so much to all the patrons who sent in their questions. You too can support the show on Patreon for a mere dollar a month. Thank you to everyone out there wearing Ologies merch from Ologiesmerch.com. Also, if you need shorter kid-friendly episodes that are classroom safe, we have them in their own feed for you called Smologis. You can get them for free by subscribing to Smologies where we get podcasts. Also, thanks to everyone who leaves a review for us, which helped the show so much. I read them all. And this week, Unfolded Shoe wrote one that said

The other night I had a dream A dream in which I was in a lecture hall being taught by Professor Allie Ward and assistant professor Jack Black. I don't know if you two will ever teach higher education together but needless to say this is my favorite podcast. Unfolded Shoe I don't know if that will happen but I am open

to it. Also we're doing our first ever live show. Not Jack Black. He won't be there but I will. It's on Monday November 17th at the Bell House in Brooklyn but we are sold out but that's good news because it means that they're might be a bigger tour coming soon. So we're going to pilot it on the 17th. We're going to see how it goes. Okay, so let's get into strigiform. Straight up, it comes from the Latin for owl,

which comes from the Greek for owl. So cozy up and a blankie. Sit on the porch and the dusk to catch some owl parenting facts, why they have pokey things on their heads, facts about eyes that left me unable to think about anything else. Owl hoots, roosts, nests, perches. Why, so silent in the night if you should get an owl box in a yard, a high-profile case in the news involving owls, how researchers study and check up on them, how to boost their numbers where they need it, and what happens when there are too many owls? Also, how one walk can change your life with this part one of a two-part episode with researcher, professor, and Gordon Gullian endowed chair emeritus at the University of Minnesota, owl experts, and one of the

Loveliest ologists, Strigoformologist, Dr. R.J. Gutierrez. My real name is Ralph Joseph Gutierrez, but everybody calls me Rocky. I've been called Rocky since before I was born, apparently. Who decided that? My mother, actually. My mother said that when she was pregnant with me, that if it was a girl, she would name her Rehanya, and it was a boy, she'd name him Ralph and call him Rocky. Was it a Rocky pregnancy? Oh, I don't know.

She made that decision way beforehand. At least that's the family theory. anyway. Or legend. I should say legend. Well, it suits you. I feel like I think about you scrambling up rocky surfaces in the woods, looking at nature. So it kind of works, right? Right. Yeah. I love this sweater, too. Was this a sweater that you found or was this something that was made for you? No, my wife made this sweater. She knitted it. It was the first one she made, she's made a bunch of sweaters for me beforehand, but she designed this and then knitted the spotted owls because that's the primary owl I work on. Now, I liked it so much

ever since then, she's made a new sweater for me every year of some species of howl I've worked with or some other species that, you know, we've both seen someplace in the world. And she's pretty amazing because she designs the whole thing from on a piece of graph paper. and then spends, you know, a good part of the year netting it. They're actually works of art, so. Katie sounds amazing. If she weren't already married, I would ask her to marry me. She sounds like the best.

Yeah. And now the spotted owl, this is your primary study species. That's correct. Take me back a little bit to when owls started to sort of capture your attention. How far back does it go? Were you a birder or did you start looking at other things outside and then and an owl flew over your head. What happened? Well, I'm glad you asked that question. I was hoping that you would because this is a story I've never

told anyone. I never shared this with anyone, including my wife. And one time I went fishing with two of my cousins when I was about, it must have been somewhere between eight and 10 years old. And we went to the Real Grandi River, adjacent to Taos, New Mexico. Mexico. So this is near the 800 feet deep Rio Grande Gorge. Think of steep, craggy rocks and sagebrush and the arid American Southwest plain, rimmed by mountains. And on the west is this huge black chasm going through this plane. And that's what we call the Rio Grande Box. So we drove to the box and then we were hiked down into it. And we got down there about evening time. my two cousins says, well, you wait here, we're going to go find a campsite.

And I'm just a little kid, you know, I mean, I'm, I don't know, you know, one thing from the other. And I'm sitting there, and it got darker and darker and darker. And I'm starting to get more and more afraid and scared, and I'm shaking. And all of a sudden, it was dark then by then, but not a full moon. So it was quite a dark night, not a pitch black night, but definitely really dark. And I looked up and I saw a great horned out. I could see the ears and the outline of the thing. I couldn't make out the definition.

And I went, wow, you know, that was really interesting. And then its mate flew in and sat next to it. So then I started thinking, well, I can actually see these things and it's dark. And at that time, I didn't realize I had a very high nighttime visual acuity. And so I just then, you know, followed the river band. and finally found them, you know, jawing it up and around the campfire. And I don't know what they were thinking. They were just going to lead me there all night.

So years later, I was in the Army, 17 years old, going through combat training, and they put me on guard duty out in the middle of the bush. And I'm sitting there by myself and I'm getting more and more spooked because it's darker and darker and darker and darker. And they would play tricks on you. They'd sneak up and, you know, if they caught you, then, you know, you get demerits or whatever, you know, they yell at you. And so I was getting all freaked out. And then I started thinking, so wait a second.

I could see those owls. And I could see walking along the creek. I said, there's no one going to sneak up on me. I said, I can see better than anybody. And then that's when I made this big connection with the ability to see at night. in the owls and what made me really gravitate towards owls. And so thereafter, whenever I had a chance, I would spend time looking for owls in college. I even would find, say, a great horned owl nest. And then I'd go in the evening after classes and just sit there and watch them, you know,

out of distance, so I didn't bother him. Eventually, I was, had my first faculty position at a Ivy League school back east. And a paper came out in a journal about the relationship between spotted owls and the old growth forest. And this late 1970s paper, spotted owl abundance in young versus old growth forests, Oregon, was published in the Wildlife Society Bulletin. And it was co-authored by Rocky's future colleagues. And it begins by addressing that preliminary studies indicate that harvest of mature forests in Oregon and elsewhere may be causing the spotted owl to decline in number birth. And as a result, it says there is considerable interest in the habitat requirements of this owl. Whether spotted owls can exist in even-aged second-growth forests created by

intensive timber management is of particular interest. So more on how the spotted owls are doing in a bit. But Rocky headed west after reading this paper to the forests of Humboldt State University to teach and to start up more research with some grad students. And my very first graduate student wanted to study Spotted Alps. And his name was David Solis. And David was a Vietnam vet. And actually, many of my early students and assistants were vets. And I was very partial to Vietnam vets for obvious reasons.

So I thought at the time, I said, you know, David, I said, this Spotted Al could be a really big deal. This is, we're talking 1979. Oh, my God. When it wasn't a big deal. Because now 45 years later, the Spotted Owl. ecology is a very big deal. And research began to show this steep decline of spotted owls in the Pacific Northwestern United States. And as a result, these new restrictions on logging were imposed

to save the old growth forests and maintain the ecology. Loggers did not enjoy this. And apparently they hung effigies of dead spotted owls in sawmills. They slapped bumper stickers on their trucks that read, I like spotted owls, fried, and kill a spotted owl, save a logger. The issue of the spotted owl conservation is drama, and it has been for decades. And from what I've been reading, it's really politically charged. We're going to get more into the standing of how many of these owls are left in the wild, what the status is, and what ecologists think we should do about it. Again, lots of drama.

But the short of it is, it's a big deal. And when you look at the authors on so many spotted owl papers, you'll see R.J. Gutierrez. About 75% of his grad students of the years have worked on owls. But from our first conversation on the phone, as I was parked on the side of the road, asking him to be on, he has always been really humble and gracious and credits others for their work. I've just been blessed by having just a wonderful group of students who have contributed so much to science and conservation of the spotted owl. And people, I know this makes you uncomfortable, but people sing your praises as the owl guy so much where you're named in books about owls. People talk about you, the legend of Rocky Gutierrez of like the owl guy to the point where I was chasing you down like you were prey, hoping you would be on this episode.

I'm so excited. And of course, the praise is not something that he accepts easily. It can be hard to see yourself as others do. even if you have great vision. Do your pupils just get bigger than other people's? Or were you a night owl yourself? Or have you always been like an evening person? Actually, I'm a morning person, which is sort of surprising.

Usually go to sleep at 9 or 9.30 and get up at 5 and go swimming. But when I work on owls, of course, you just adjust. I suppose that is one of my characteristics is adaptability. So whatever the situation calls for, I adapt to it. And I think that's something I learned both from, you know, working as a kid and also being in the military, in the Army, is that you have to adapt and you have to respond to situations as they arise. Because I'm definitely not a night person. I prefer to go to sleep early. When it came to owls being a steady species of yours, was there a moment when you?

you really realize, like, owls are, and I'll couch this, but owls might be better than all the other birds. Yeah, I said it. Do you have a soft spot for them particularly, and what is it about them that you love? Well, actually, my doctoral dissertation was on quail, mountain quail. No one had ever done a doctoral dissertation on mountain quail. And when I told my major professor, Starker Leopold, at Berkeley, that I was going to work on Mountain Quail, pushed his chair back from his desk, and he opened the drawer, and he pulled

out a little string. And he said, here, here's a rope. Go hang yourself. He said, nobody's ever been able to work on Mountain Quail. He said, so forget about it. And I said, you don't say you can't do something to me. That's just like raving a red flag in front of a bull. And so I took it on as a challenge, and I did complete the first Ph.D. on Mountain Quail. And likewise, with owls, they are a challenge to work on because they're nocturnal and they're often difficult to find. But with a spotted owl, fortunately, we have many people have worked on them. Eric Forsman, a good colleague of mine from Oregon, he was the first one that really studied spotted owls and learned a great deal about them that set the...

sort of the foundation for the rest of us to work on these birds. And so I'm not really a legend in that respect because there's many other people that worked on spotted owls that probably know a lot more about spotted owls than I do. But regardless, that's one of the things that I find in working with species is I really enjoy challenges and something that is demanding and hard in, especially if the habitat is rough, you know, and mountain quail and bottared owls both are in usually in steep mountains and, you know, you've got to be in really good physical condition to go

find them and so forth. So this is something I really enjoy. It's the challenge of these species, the galloforms as well as the owls. Just a heads up, a galliform is like a chicken, a turkey, a quail, the kind of awkward loping around the ground birds, the landfowl. Galliform comes from the Latin for rooster, and we do have a two-part episode on chickens that we will link in the show notes. You're welcome. Also, Rocky's longtime colleague, Dr. Eric Forsman, is also an accomplished strigiformiologist, and we'll touch on him and rodents in a bit. And when it comes to strigiforms, right? Strygeformies

Strygiformis. What makes a stridiformi a strigiformi? What makes an owl an owl? Well, one way to you think about this is think about the owl as an illusion. So if we peel back layers of this

illusion, we get an idea of what the owl is like. So let's look at their overall appearance. So when you look at an owl, they have a big round head. And then they have big eyes. And so that sort of attracts people to owls, at least in North American Europe. So not every culture is like me a simp for owls. Some folks, especially in different parts of the

world, are strigiformyphobes. So more on that in part two. And so you have this big head with big round eyes. But in fact, their skull is like a triangle. So if you put your fingers together and make a triangle, that's what their skull actually looks like. Oh. Okay. So, let's say your thumbs are touching, right? You've got a triangle. The short side, your thumbs are the eyes. And then your pointer fingers would be the beak. So owls are not pug dogs. They are like golden doodles with a dog snout under a bunch of fluff. And so it's an illusion that their heads are actually around. Their whole beak and everything, it's just this big triangle. And what you're seeing is a combination of the eyes. which are actually in tubes, so they're elongated eyes that are held in place rigidly by something called a scleral ring. You can think of it as like a bunch of shingles, bony shingles, and they provide a rigid structure for its eyes. And then around that is this huge facial discs that owls have. You can see that on all the owls,

that they have this mass of feathers that makes the owl appear as if it has this big, rounded head when it actually it's triangular when you consider the beak together. And are their eyes tubular shaped or are they in tubes? They're tubular shape.

What? Yeah. Like a sausage eye? Yeah, and they're sort of strange. Of course, this varies by the species of owls, but most of them have that elongated shape. And there are actually some mammals that have that, too, like bush babies and some of these nocturnal primates have these elongated eyeballs. So owls, big puffy feathery face and tube eyes like big fat worms held in place by a bony plated pipe called a scleral ring.

And now they have this disproportionately large eyes in a big head. I mean, their eyes are so big. like a great horned owl, is 5% of its body weight. What? And a human, for example, it's like 0.003% of the body weight. So they have a lot of investment in their eyes. And in those eyes, because they're held in place, they cannot move the eyeballs. Like, we can sit there straight ahead and watch people out of the corner of our eye,

and we have great peripheral vision. Owls can't do that. Their eyes are fixed in their head. And as a consequence, they have to move their heads to see where they're going. Now, owls are different than most other birds, in that most other birds have their eyes on the sides of their head. So they have good peripheral vision, but not good binocular vision. And binocular vision is very important for depth perception. And the owls have about a 70-degree field of binocular vision. Humans, by contrast, have nearly 180-degree binocular vision. But this adaptation, it's not just a badge of predator versus prey.

A bunch of plant eaters who have to swing through trees have two forward-facing eyes because it helps them judge the distance before leaping between branches and getting smacked in the face. But Rocky, because he's awesome, emailed me later wanting to impart more details about their vision. He's the best. he wrote, owls see way better in the dark than us and other birds because at the end of those sausage eyes, he says, they have a higher proportion of rods, which are the light sensitive structures relative to the cones, which are the color sensitive structures than other birds or humans. In fact, he continues, in the retina, there is something called the foveal pit, which is a depression

in the retina, and that's highly sensitive. It's densely packed with only rods, the light sensitive structures. In addition, he says, many owls have this reflective layer behind the retina. It's called a tapidum lucidum, and it gathers even more light into the rods. And he says, this is why if you shine a flashlight at some animals, their eyes glow. It's light reflecting off that tapidum lucidum layer. So now we know this. And if you have a soft spot for creatures of the evening, you can enjoy our episodes about lemurs, raccoons, possums. We even have a whole eye episode. But yeah, owls, great binocular vision via those tubes and pipes. But as much as an owl would like to, they can't give a lot of side eye. It's not as wide as ours because their other

eyes are fixed, but it still gives them the ability to focus in and determine the distance of prey is, for example. And so because they have this fixed eye and binocular visions, what they have to do is turn their head to see where a sound is coming from. But one of the adaptations they have evolved to compensate for this restricted eye is that they can rotate their head, they can swivel their head, 270 degrees. So they can turn it all around. When you think about twisting your head, well, we just can't do that.

I can barely get my head 45 degrees around. But when they twist it, the pheromone or pheramina that the arteries of the neck going up into the brain they run through these holes in the vertebrae and they are actually quite wide so that when they twist the artery doesn't get constricted oh wow because if we weren't able to do that somehow we'd probably constrict our carotid arteries and we'd pass out but they don't do that they just switch all the way around And the other thing is, owls have 14 vertebrae in their neck, whereas we only have seven. They have a very long neck.

And again, that's an illusion, because if you look at it, they look like they have a little short neck. But actually, they have a really long neck. And it's all because of this facial disc is covering things up and the feathers on their shoulders and so forth. And the facial disc itself is unique in that they can actually control these feathers. and it's like us putting our hands behind our ears and cupping them. And we do that when we want to hear something far away and we put our hands behind our ears and cup them. Okay, so looking under the hood, again,

owls can spin their necks like an exorcism because they have twice as many neck bones as us. And under all those feathers, they only have two fewer neck bones than a duck. There's skellies, I looked them up. They look like a completely different bird. You'd be like, what bird is this? You would not guess an owl. They also have, again, bigger holes for their arteries, and those disc flat faces that we love are not structural so much as tweaked through their feather adjustments.

I know you're saying the legs, the legs, the legs, we've got to talk about their weird little frog legs. We're going to get to that in part two, I promise. And also on their ear flaps, they have these little flaps on their ear that can control the opening and closing of the ears, but they also have feathers behind them that also have feathers behind them that also. can direct sound into their ears. So owls are hunting machines, but why do some of them have so much style in the head region? And then another thing about them is an illusion. Sometimes you see these little, what we call owl ears that sticking up on great horned owls

and screeching. Yes. What are those? Well, we think they're probably signals of some kind, a signaling device, that owls that are primarily crepuscular or that hunt in. the twilight hours of dawn and dusk, that's a term we call crepuscular, and we think that they might be signals between the pair, but they are not any, have anything to do with the ears. So what do you know about the ear?

The years are actually big, long slits on the side of their heads, and the ears themselves are offset. So the ear on the right-hand side is higher than the one on the left, and their head is proportionally much larger than most birds. And as a consequence, when the sound hits those ears, this is sort of mind-boggling, but the difference in time between the sound hitting one ear and the other ear is 30 milliseconds. And they can actually tell the difference of the direction of sound based on that teeny, teeny, you know, millions of seconds sound.

to illustrate, here are two beeps that are 30 milliseconds apart. And these are all these adjustments that the owls have made. And so when you look at them, it looks like they don't have ears, but they actually do have them, but they're just these narrow slits hidden behind feathers. So the owl is sort of enigmatic in the way it appears to you. But when you, as we have just done, pull those things apart, you start to see what an owl is really like. which is a bird that has evolved to conquer the night.

Are all owls nocturnal or crepuscular, or are there daytime owls? There are daytime owls. There are these crepuscular evening and morning hunting owls. But the majority of owls are nocturnal. So like burrowing owls and short-ears owls, they're primarily diurnal and screech owls, Great horned owls, spend quite a bit of their time in the evening, in early morning hours hunting. But most of the rest of the owls are nocturnal. You know, when I first moved to my neighborhood, well, first I had lived in an apartment in a busy part of L.A. for a while.

But when I moved to this house, we had much more nature. And I found a feather, and I looked at it closely, and I realized it was an owl feather because it had little sort of a serrated edge. and I freaked out so excited, and sure enough, we have a pair of great horned owls, and you can hear to at night, all at night. It's so great. I love them. We see them all the time. But can you explain a little bit about how they're so quiet? Because one will fly right by me. You can't hear a sound. And do all owls have that or only some? Virtually all owls have silent flight. Now, the one The ones that don't are the ones that hunt fish, like in the genus Katupa and some bubos, like

the Blackasson's fish owl, the world's largest owl. So these are 10-pound chunkers, and if you are thirsty for more info, I would like to direct you toward the wonderful book by another Striga-formiologist titled Owls of the Eastern Ice, a quest to find and save the world's largest owl by Dr. Jonathan C. Slat, who was a grad student of Rockies. And one reason I was so thrilled to get Rocky on this show is that Jonathan wrote about doing field work with him. So Jonathan writes about some field work that he was doing in Asia, and he writes that his guide on the trip had not met Rocky before. But his past experiences with foreigners had taught him that most were doughy, pampered, and unable to bear the discomfort of

the insect swarms, the cat holes, and the insect swarms at catholes that awaited them. Jonathan continues, I assured the guide that Rocky took a perverse pleasure in suffering of all kinds and viewed discomfort as an adversary best ignored. Still, doubts lingered until they met when Rocky's rough hands and KT's ropey physique showed him they were a pair accustomed to an honest life outdoors. Rocky, in his 60s, resembled a snowy owl, short with large eyes under a mop of white hair. KT was about Rocky's age, slight, quiet, and highly observant. So yes, you can pick up Owls of the Eastern Ice,

a quest to find and save the world's largest owl by Jonathan Slat. We'll link it on our website. You can learn all about these largest owls, the endangered Blackestan's fish owl, which is allowed to brag about its nearly two meter wingspan. Wings as wide as your dad is tall.

Not me, not your internet dad, but like a real man dad. There's no premium on being silent because the fish can't hear you. You know, they drop down either from the perch above the water onto there or like the Blackson's Fish Owl will oftentimes walk along the edge of the shore or jump on rocks and then jump into the pool and grab the fish. Getting back to your observation, which is wonderful, actually. Thank you. Ows have a couple of adaptations. One is that, as you noted, they have these serrated edges.

And that's caused by the loss of these little hooks that are called barbules that most birds have that actually keep the feather rakesy locked together. And they've lost that. And so people have thought that that gives the owls a silent flight. but there's some hypotheses that it actually has evolved to reduce the turbulence behind the wing. And then they have another adaptation with these velvety structures over the tops of their flight feathers that, in fact, is the one that's reducing the sound that they're making. And for more on this, you can please enjoy the 2017 paper features of owl wings that promote silent flight,

which cites plenty of other research into owl's stealth. And it notes that the large wings of these birds contribute to the noise reduction by allowing slow flight and the serrations on the leading edge of the wing and that velvet-like surface have an effect on noise reduction and they also boost aerodynamic performance. And it notes that the fringes at the inner feather veins as well as the fringed trailing edge of the wing reduce noise.

So it's a combo of those two factors. And like everything that is cool in nature, of course, engineers are like, how can we do that too? But it might take like around 60 million years to get it dialed. Those two adaptations coupled with the way they actually approach a prey, or in your case, they would fly by you to go another place, they often launch themselves and then glide. They don't do the typical bird flapping and moving. They will, of course, when they're flying distances, but when they're hunting or attacking something,

they come in without flapping. So the turbulence is being reduced, their sound is being reduced, and they're restricting their movements of their wings. So they're virtually silent in flight. I know a lot of people say, well, I heard an owl, you know, fly by me and isn't, now you didn't hear them. What you heard was when they landed on the branch, and the branch is going up and down.

But that's what you heard. When you think about it, these things can go right past you and you will not hear them. And are they using that to sneak up on prey? Are they able, with their giant huge sausage eyes, to see rodents scurrying and other crepuscular or nocturnal animals and they're just swooping down and picking them up? Is that how a lot of owls hunt? Well, we call them mostly perch and pounce predators. When I've watched them attack prey, you'll see.

them look very intently at something. Of course, we often use mice to get them to come down where we can catch them. It's basically like watching them hunt. It's artificial, though, because we're putting some food out. But they'll often look intently and sometimes bobbed their head to focus in on what it is. And once they realize they just launched themselves, come in, and then extend their talons and grab them. But they can also relocate. So if they hear something and they think they see it and maybe they can't really focus on it because of the obstruction of vegetation or whatever, they'll fly to a different purge and then get another view of it. And once they're confident that they can catch this thing, they make the attack. We've noticed in doing these studies feeding mice to owls that some of them seem to prefer taking prey off the ground.

others from branches or the size of the trees. So we call this phenomenon when individuals get a search image for a particular type of prey. What do you want? What do you want? And now, of course, owls, when you look at their diet, they're eating lots of things. But some of them seem to be very adeptive or prefer to take animals off of trees or off bushes are off the ground. They have their own preferences for how they might go about doing this. And I got to ask, what's that fieldwork like? Do you have a pouch full of live mice? Are they dead

mice? Are you toss them in a field? Are you sticking a dead mouse on a tree? How do you figure that out? Well, what we do is usually use live mice to feed to them because we have had lures, that little toy store mouse, that we pull along. But they seem to know the difference between something that's real and not real. And as a result, we, well, Eric figured this out, putting a live mice out there, and then they'll come down to catch it. And over time, we've developed different sorts of techniques, first some nits, nisnets, and then Eric developed a capture pole, and then we made noose poles and various devices to catch them pantraps, what not. And now it turns out the easiest thing to do is just catch them by hand. What? How? You put the mouse down and they come for the mouse and just snatch them by the foot.

Oh, are they so mad at you? You know, it's really interesting that when you catch an owl, they often will bill click. They pop their bill together. And that's sort of an agitation display and maybe even a threat. display as well. So one of the things that we realized, if you watch a pair of als together, and this is one of the things that makes them so adorable to people, is that they often roost right next to each other. And then they'll aloprene. What does that mean? So that means that they preen each other. So they'll get up there and they'll preen their face.

And we thought, you know, what if we did that? You know, we just preen their little faces and stuff like that, you know, because they're just bill snapping and struggling and trying to get away and then just go like that and you just start alopreneing their face. And pretty soon they just relax. Oh, this feels so good. That's exactly what they're doing. Because you're simulating, well, we think it's, aloe preening serves a couple of functions. One is reinforcement of the pair bond between the pair. And also, it's feather maintenance because an owl can't really maintain its feathers very well on its face. They can scratch and so forth. But when they get the mating their face, fix up the feathers and so forth. Are they mating for life

most owls? Or is it totally dependent on the species? Ooh, a little cliffhanger. Stay tuned until after the break to find out about owl romance. But first, let's donate to a cause that Rocky loves, which is the International Owl Center, which is in Houston, but Houston, Minnesota. And their mission is to make the world a better place for owls through education and research. And they also have an international owl festival in March. Rocky and John Stratt were speakers last year. And they have a bunch of resources on their site about owls, bird rehabbers, even a world owl hall of fame, which brings public recognition to the owls and humans that have done great things to make this world a better place for owls. You can find out more at international owlcenter.org. So I'll toast to that and also

donate to that. Thank you to sponsors of the show. Okay, so I had just asked Rocky, are they mating for life most owls, or is it totally dependent on the species? Well, for most species, we really don't know, but it appears that most species maintain a long-term pair bond. I wouldn't say mate for life because they do, in fact, divorce. Oh. Look at me, son. It's not your fault. They'll leave a mate and go to another mate. It very well might be that if they're failing to nest, one mate will leave and try to find another nest. That still needs to be investigated more fully. But one of the few that we know does not make annually seems to find new mates as a burrowing owl. They will seek out

new mates each year. What are those nests like? You know, we put up an owl box before we we realized that mostly barn owls like those, and we already had some great horned, we were good to go on the owls. So now the great horned owls sit on top of the owl box and they do their pounce and perch from there. But what kind of nests do a lot of these owls have? Are they finding a hole in a tree? Are they building them out of sticks?

Are they finding another abandoned nests? I know pigeons suck at nesting because they don't really need to be good at it if they're on a cliff. But what about owls? Yeah, owls don't build their own nest. Oh. Your observation is correct. But they will seek several different kinds of nests.

As you noted, they will find and use old abandoned raptor nest, nests of ravens. They will sometimes nest in the crotch of a tree where there's accumulated debris. They will nest in witch's brooms. They'll nest in big cavities. If a tree is broken off at the top like an old growth forest, a lot of times older trees get weakened by disease or fungus and a windstorm will break the top of the tree. And then, you know, 10 or 15 years of rotting, there's a shallow depression there and they will nest inside that depression. Sometimes I nest inside a depression sometimes. Also, I thought Rocky was just being cute, but a witch's broom is a real thing. I did not know this.

And when a tree has a pathogen or some wonky growth, it can grow this clot of weird little curly branches. They look like a bird's nest, so much so that owls see it with their sausage eyes. And they say, hell yeah, I live there now. And they don't put any kind of material. They just, whatever is there, they just lay their eggs on it. And, of course, Great Horned owls and some other owls will nest in cliffs, just like these pigeons will. But the pigeons usually build a little flimsy nest. They're not great nest builders, but they do build a nest, whereas the owls don't.

And in your situation, as you mentioned it, I was thinking, well, maybe the size of the hole in the box is not big enough for a great horned owl. That's a possibility. Typically, will you have owls that overlap in range, or are they like one owl, one pair of owls is enough for one place? or will they start eating each other if they're different species? You might be talking about two different things, but let's take these in order. So if you're talking about the same species,

there can be adjacency in pairs and some small overlap in the home range, but they have inside that home range is an area that is defended, and we call it out the territory. And that's an exclusive zone. So they will exclude any other, owl pair from coming into that territory if they know they're there. And that's one of the

purposes of hooting is to announce the territory and to tell people, stay out of here. This is my place. Leave. Get out. But then there's the other question about different species of owls. And we have done research on this. And we find that owls that are syntopic that is occurring in the very same habitat can only coexist if they're eating different foods or their different body sizes, which suggests that there's something going all with a trophic level or the way they for it. So they have to be big enough difference in size for them to coexist in the same habitat. But a lot of times the little owls are taking their chance being in the habitat of the bigger ones, because I'll get eaten.

Yeah, I was going to say, like little cornish game hens to them. Should people put up owl boxes? If someone wants to have an owl in their yard, what's the best way to do it? Yeah. Again, it depends on where one lives, but very often in suburban areas, if there are sufficient trees, there's often small owls around like pygmy owls or screech owls, and you can entice them to live there. And very often, holes are a limiting factor for these small owls. So putting up nest boxes, you very well might attract now. And of course, if you live out in

a country, then there's all kinds of owls that you might be able to attract. And therefore, you can put larger boxes or medium-sized boxes and so forth. But you have to be careful about this because you put owls in proximity that liable to eat each other, you might be doing something counterproductive. So be careful about what you're trying to attract. Should you mount the box to a tree, or is it better on a freestanding pole? Probably anywhere on a tree. But if you put it on a pole or on a tree, it's often helpful to place some kind of a barrier that a raccoon or other animal can't go up the pole to get it. Because if a raccoon can crumb up a pole or a tree and reach its little paw inside

and grab an owl at for dinner, it'll do that. Poor little baby owls. Are owls good parents? They are wonderful parents. And this is one thing about owls. They have a strong division of labor between the male and the female. So typically, the male owl is smaller. the female. There's lots of hypotheses about why there's this reverse sexual dimorphism, the males being smaller and the females being larger. Be that as it may. The male is primarily the provider of food. They go out and forage and catch prey, bring it back to the female who's sitting on the nest. And the female basically, after she's laid the egg, she incubates him by herself and primarily broods the young. And the male,

brings her food. Short king. She only leaves the nest to defecate and to do feather maintenance and the like, or come out and receive prey. Zach Piri, one of my colleagues that I work with at the University of Wisconsin, he had a graduate student, Sienna Zulu. And Sienna would climb up these trees and put a night camera on the nest and would determine what the prey was. And in this particular video, you first see a male owl coming in and landing and depositing a wood rat and then the female coming from somewhere else and going into the nest and then you see the little baby pop-ups up its head. But normally what happens is the male will arrive at the nest with a prey item and he'll give a soft call or a hoot and the female will come out of the

nest and then he'll fly over to her and she takes it from him and then she goes back in. And because the young are too small to really handle the prey, she'll tear it apart and feed them bits. And the things that they can eat like the skull, she just pops them down. A delivery for mom, breakfast in bed, fresh, dead rodents. When you've got fuzzy tiny screaming owlets every day is Mother's Day. What co-parenting? So one time I had a project leader who was leading one of a project in Southern California in the San Bernardino Mountains, the hay. And he called me up and he said, I want to show you this nest. He said, this female has not

moved off the nest for like two weeks. And I said, that's pretty weird. Because oftentimes when you feed the male a mouse to try to determine whether or not they have a nest, because the male will take the mouse to the nest, and you chase them through the forest while they find to the nest. And that's how we define the nest. Anyway, this female wasn't doing that. So we went out and looked at it. And you could see the female's head, just the top of her head and this broken top tree and her tail sticking up. And we walked around, around, and looked at this and I said, you know, you ought to climb this adjacent tree and just look in there and see what's going on. So Bill, being an expert tree climber, he scrambles up the tree and looks in. And he says, I think she's dead. I said,

Yeah. So he came back down and he put some climbing spurs on and went up this broken top tree and he reaches in there. And this female had died and the egg was in her breast. So in other words, she starved to death, we think, while waiting for the thing. And she was so tenacious to, well, this is what we're speculating. She didn't want to give up incubating that egg. And so if it was a bad year and the male couldn't bring her nest, she just hung on as long as she could. And then it was too late. But the alternative, of course, is she got some disease or something happened to her. But, you know, it didn't look like anything other than she had starved to death because she was emaciated.

So it was really, it's sort of sad. But it gets to your point about being, you know, good parents. I mean, they are tenacious parents. They will take care of their young. So as we mentioned in the Lutronology episode, which was a devastating expose, on otter behavior. A mother otter might be on the brink of death because she's nursing offspring who are old enough to forage on their own and they just keep going back to the teeth. And this is none of my business, but I'm pissed at those otter children. Also next week, we're going to talk

more about spotted owl ecology and which owls in the world are the most threatened. But how can you know right now if you are neighbors with an owl? Do you know you've got an owl nest around if you see pellets in a certain area? And also, why do they, unlike all these other birds, have to kind of barf up a clot of lint and bones? If you find pellets, that does not necessarily mean that there's an owl nest nearby, because an owl could be nesting somewhere else and roosting there and depositing pellets at the roost. And a nest, side note, is where they worm and they feed them babies, but a roost can be a nearby spot that they like to nap during the day, just generally chill.

It usually means that the nest is somewhere in proximity, but not necessarily all that close. And the other thing is about these pellets, as you mentioned, so I started thinking about, what do you call it when you study pellets, you know? I don't know. See, there's scatology, right? Well, there's study of feces. You know, and I started trying to figure this out, reading books and looking things up and couldn't found anything. Well, you know, I guess you could call it barfology, where they're barfting these, these pellets up.

So yes for me. But let me back up one second here, is that pellets are cast by over 300 species of birds. Oh. So it's not restricted to owls. So lots and lots of species do this. But the owls seem to form the biggest mass of ones. And it turns out that the avian stomach has two parts. And one is a glandular part like our stomach.

They call it proventriculus. And then the other part is the ventriculus, which is what we think of as the gizzard. So you have like this real stomach and then this like grinding organ called the gizzard. And all the soft parts get sort of digested and broken down in this stomach part. and then move over to the gizzard where it's more finely ground up. Well, in the case of the owl, it turns out that the pH of their stomach acids is higher than a raptor, for example. So a raptor is like a pH of 1.8 or something like that, and an owl is like 2.5.

And higher pH, remember, means it's a weaker acid. Confusing, I know. But that's enough of a difference that they cannot digest these big bones, the hair, and all that sorts. Whereas many of the typical raptors, they digest a lot of the bones. They still cast pallets and stuff, but they'll digest some of the small bones. The owls don't do that. And so as the soft parts are being digested and moved to the gizzard, the other undigestable parts that can't be broken down are pushed to the top of the, stomach and sort of compacted there. And then once the digestion process is completed, it is formed

this little mat. That looks like a little turd, you know, but depending on the size of the owl, the bigger the owl, the bigger the pellet, and then they upchup them. They barf them up. Delicious. People have speculated that this is a constant, the time of it takes them to make this pellet and regurgitate it is probably related to the size of the. meal that they get in there. And I actually think that in some circumstances, if their pellet is already formed and you offer them a prey, I've seen them actually look at the prey and then start upchucking a pellet, then come down and get the one that you just put it out.

They're like, let me make a little room. But they can't form it immediately. They're basically saying, well, you know, let's get their show on the road here. Can I ask you some questions from listeners? Are you doing okay? I know I've kept you. No, I've got all the time you want. Okay. Amazing. I love this. So ask visionary people, blurry questions. And thank you so much again to R.J. Rocky Gutierrez for being on not just this week, but next week as well. We'll have part two. We have links in the show notes to find out more about Rocky. And, of course, we post more research on our website. This will be at alleyward.com slash ologies slash strigiformology.

next week we are back with all of your juicy owl questions like parliaments barns bard owls if you should hoot at your owl friends omens folklore what not to put in your yard a homicide case that has baffled detectives and ornithologists alike and so much more so stay tuned and come back for that part to you next week and we are at ologies on instagram of blue sky i'm at alley ward on both smologies are shorter kid-friendly episodes available wherever you find podcasts just search smologies s M-O-L-O-G-I-E-S. Ologies merch has totes and shirts and hats at Ologiesmerch.com. Thank you to patrons at patreon.com slash Ologies for supporting the show. They also get first dibs on tickets for live events, which is another perk for a dollar a month if you join. Thank you also to Aaron Talbert, who admin's the Ologies podcast Facebook group. Aveline Malik makes our professional transcripts. Kelly Ardwire does the website.

Nocturnal and Diurnal. Scheduling producer is Noelle Dilworth, our Eagle-Eyed managing director. is Susan Hale. The pair of editors sharing the branch is Jig Chafee, and lead editor, Mercedes Maitland of Maitland Audio, Nick Thorburn hooted out the theme music. And if you stick around until the very end, you know, I might tell you a secret. I will tell you a secret whether you want to or not. And this week, it's that whenever I have to transfer files via an SD card from my recording device onto my laptop, I have to use a dongle, right? Because life isn't hard enough in 2025. But a little secret. I usually just rip the dongle out without properly hitting the eject icon. And I know

one day this is going to ruin my life, but I've gotten away with it thus far. So feel free to either, like, soothe my soul and tell me it's fine, or you can scare me straight on this one. I appreciate it in advance. Okay, more owls, more rocky next week. It's so good. Okay. Bye-bye. The owls. Nephology. Nephology. Seriology. Salinology.

The owls are beautiful.