transcript

Speaker 1:
[00:05] Hello and welcome to The American Birding Podcast from The American Birding Association. I am Nate Swick. We've got some fun stuff coming up here at the ABA that perhaps listeners of this podcast would be interested in. I always do an appeal for membership at the end of the episodes, but I will hold off a little bit this time around, or at least add some more context, because we at the ABA are gonna host an old fashioned live membership drive in May, May 19, to be more specific. We'll be streaming a few things online, which I suppose makes it less than old fashioned, but it's hard to get a birding organization membership drive on network TV these days, so we're doing the best we can. What this means is that we have a generous donor who is willing to donate one of our board members, Willie Hendrickson, who will contribute $100 for every new or returning member to the ABA through the end of the month, through May 31st, up through the first 200. So that's $20,000 potentially into the ABA's nest egg, as it were. On the 19th of May, we will be live streaming for, I'm not sure how long, we're still working on that, at least three hours, maybe more. Greg Neese and I will do a special What's This Bird live, and podcast fans may be interested to know that I am planning a special live Take It or Leave It episode, so if you've ever wanted to contribute to a Take It or Leave It episode, you can send me some hot bird takes at podcasts.aba.org, or you can join us on the live stream and you can give your opinions while we're doing it, while we're doing the thing. I'm planning on getting some really good hot take havers to participate with me. It should be, no, it will be, it will be a lot of fun. So join us on May 19th, more info to come as we get closer, and if you're thinking about joining or renewing, this is a great time to do so. Heck, if you joined last month, you can even renew early, and it will count towards our goal. Not that I'm trying to juice the numbers or anything, but I'm just giving you the information that you need to make an informed decision. So, on to the show. Couple weeks ago, I talked about a really cool article that was published in the most recent issue of Birding Magazine, and it's online for free about electronic pitching. It was by Peter Pyle and drew somewhat on the work of a Stanford student named Marty Freeland. Marty agreed to join me to talk about his work and his thoughts on pitching electronic or otherwise, and it turned out to be a really fun conversation that I am thrilled to share it with you right after this week's Rare Birds. This is your Rare Bird Focus for the third week of April, 2026. Let's talk fly catchers this week. Starting in Alberta, where a female Vermilion fly catcher is photographed in Banff in the southwest of the province, maybe appropriate for the species found primarily in the southwest of the ABA area. This is a first record for the province and only the second for Western Canada, though now all the prairie provinces have a record of this bird, even though this bird in particular was not, strictly speaking, found on the prairie, very much in the mountains. Anyway, Vermilion fly catcher is a fairly regular vagrant to the east of North America, and in fact, most Canadian records come from Ontario and Quebec. Notably, this is not the farthest north record, though, for this species. That came from neighboring Saskatchewan, a bird that was seen way, way up at the north end of the province in 2024. And at the opposite end of the ABA area, a Cuban Peewee was discovered on the migration hotspot of Garden Key in the Dry Tortugas of Florida. This is a common resident garden species of Cuba and the Bahamas, and as such, all ABA area sightings have come from parts of Florida that are right up next to those island nations, as close as you can be to an island, I suppose. There are about a dozen records for the ABA area, the first of which officially came in 1995, though older, unaccepted accounts suggest that maybe the species might have been overlooked before then. Those are the highlights for this period, but for the full list of rarities from around the ABA area, please check out the ABA Rare Bird Alert most Fridays at aba.org/rba. You can also follow along with all the rare bird news in our ABA Rare Bird Alert group on Facebook and on ABA Community. Listeners might remember a couple of weeks ago I talked about Peter Pyle's piece that was published in ABA's Birding Magazine and is online for free about what he called electronic fishing. That essay was informed in part by the work of an undergraduate researcher at Stanford University named Marty Freeland, who's been doing some work in the sphere that has been on my mind a little bit. I sort of jokingly put out a call in the podcast to Marty to get in touch and well, he did with some thoughts and I figured it might be more interesting to have that conversation with him here or podcast posterity. Instead of over email, he graciously agreed and he is here. Now, Marty, thank you so much for your time and thanks for getting back in touch with me.

Speaker 2:
[05:24] Thank you, Nate. It's great to be with you.

Speaker 1:
[05:26] I want to talk a little bit about your interest in mob tapes slash electronic fishing, what Peter called electronic fishing. Does it come from a birding perspective? Does it come from a science perspective? A little bit of both as is usually the case with these sorts of things.

Speaker 2:
[05:44] Yeah, I think a little bit of both sounds like a fair description, that the first mob tape I made was strictly for birding purposes, and I was 13 or something like that, as Peter might mention in the article too. And it was a medley of some crow distress calls and some jays, golds and so forth, and it was really great for seeing crows and jays. I'm not sure that that's every birder's goal in terms of using mob tape. But additionally, we've had a study running for the past year or so, trying to think about the ways in which mob tape might systematically affect both how we detect birds and the birds themselves, which I think is a really interesting and maybe even more fruitful lens to get at the whole situation of electronic fishing.

Speaker 1:
[06:23] Yeah, I want to back up just a little bit and talk about making your own bespoke mob tape. How did that work? Did you have an idea in your head of what kind of birds you wanted to use? Did you pick and choose? Did you eventually come to a very effective mob tape? How did you layer all the birds together? I have a lot of questions about that.

Speaker 2:
[06:43] Yeah, for sure. I just put some corvid, scold sounds together in iMovie, a video editing program, not really designed for that purpose. I'm sure there are better ones out there. But yeah, that was just the set of birds that came to mind for me at the time as being most actively involved in mobbing. I think most birders across the ABA area have doubtless seen crows mob great horned owls or red-tailed hawks and so forth.

Speaker 1:
[07:08] How I find most of my great horned owls.

Speaker 2:
[07:09] Exactly, it's such a visible representation of that interesting behavior. But yeah, different people make different mobs in all sorts of different ways. A couple birders here in California recently tried to layer together some of the sounds that for example Okinawa rails from an island in southern Japan make when interacting with the endemic Okinawa viper, together with some other potential rail distress noises to see if that would help bring California rails out of the marshes. To my knowledge, it may not be too effective, which is an important thing to bear in mind about mob tapes, is there plenty of situations where they just don't work too well. But yeah, there are as many approaches to making a tape as there are birders, I suppose.

Speaker 1:
[07:51] Yeah, I'm tempted to try my own mob tape manufacturing. I suppose if I were thinking about the birds that I sort of encounter. Where I live here in the Southeast US, it would be tough to tip my eyes primarily, maybe a little bit of Carolina chickadees in there. Maybe if I'm feeling really crazy, I could throw in a blue-headed Vario kind of sneer, and maybe I could put something together that might get some birds out. It never occurred to me to make your own. I just have been using the ones that come on, I don't know, on the Sibley app for the most part. That's really fascinating.

Speaker 2:
[08:24] Yeah, it's always something that anybody can do, I suppose. At the same time, the more mob tapes are out there floating around, the more danger I think there is of maybe over mobbing, which is a serious concern. Maybe we can talk about that later on too. But also, no shame in sticking to whatever is already out there, or even just eschewing the practice altogether, depending on what works best for you and in your context in your area.

Speaker 1:
[08:51] Sure. So what is your process for answering these questions that you have about mob? Maybe we should back up and say, what are the questions you have? Is it effective? One, is the main one. And two, does it impact birds in a negative way? Do you have any other questions that you're trying to answer?

Speaker 2:
[09:07] I think you nailed the two main questions there, exactly. And beyond, is it effective? Who does it affect? Because clearly mob affects some birds. We've all seen birds mobbing, if nothing else, just American crows and large raptors and so on. And then, yeah, number two is the big question, the much harder to answer question, I tend to think, of exactly what this process, when manipulated by birders through playback, what does it do to birds in that context?

Speaker 1:
[09:30] Yeah. So how do you go about answering these questions? Do you take your different mob tapes out into the woods and walk transects, or is there something more subtle to it?

Speaker 2:
[09:38] I think, you know, that's the core of it, basically. But one thing to bear in mind is in the research that we've done here at Jasperage Biological Preserve at Stanford, there's a really rigorous permitting protocol before any of this kind of playback study can begin, which I think is a really good thing. It helps you, it makes you think through exactly what the possible implications could be for the birds and for your detections of them and any inferences or management decisions you might make based on those detections. And it's a rigorous process that involves a whole bunch of perspectives from a whole bunch of folks with various kinds of expertise. Like, for example, we had to run our protocols by the Institutional Animal Care and Use Committee, who are the people who govern what you're allowed to do to lab rats and so on.

Speaker 1:
[10:23] Wow.

Speaker 2:
[10:24] And as well as the reserve managers and all of that. And the way we ultimately persuaded these folks that possibly, if they're a circumscribed mob study might be permissible, was by comparison to a previously permitted study, where some researchers at the University of California, Santa Cruz had obtained permission to launch Styrofoam models of exhibitors or Aster's, I suppose, nowadays. Yeah, right. So, they were able to use the chickadees to induce alarm calls from the chickadees, as a way of standardizing the type of alarm call they were recording. And so, that is a level of intrusion that is pretty dramatic, to be honest. So, our logic was if that can be permitted in a regulated circumscribed way, maybe mob can be permitted in a regulated circumscribed way as well.

Speaker 1:
[11:04] It's a shame you didn't have any gossocks to kind of fire out of, what do I call it, potato gun cannon?

Speaker 2:
[11:10] Exactly. So, having obtained insight from all these folks, we put together a protocol that essentially consists of walking a transect along a set of standardized routes once a month, then dropping off passive acoustic monitoring devices called audio moths. It will just sit there and record sound for 48 hours. Then we come back to pick up the monitoring devices, the audio recorders, we run mob tape on the transect, the same transect that we walked 48 hours before. Then we have three data sets that are all nicely linked, the normal transect, the audio moth data, and the mob data. Then we can run various kinds of statistical comparison to look at any differences in what birds we detect there. Additionally, in a vague attempt to get at the harder question, we also have a bird banding station at Jasper Ridge. We use that for body condition data and so forth to see if in the era when we started running occasional mob tapes, there was any strong change compared to previously. We didn't find any change in the banding data, but that's not to say that bird body condition would not have been conceivably affected. Because there's no guarantee the birds you catch are the same ones who are most active in the mob and so forth. But that gets at why it's such a challenging question to answer, is in order to track bird stress responses or whatever, ideally you'd be catching the birds, weighing them, measuring them, even looking at stress hormones like cortisol or whatever. But that process itself is likely so stressful for the bird. But yeah, you know, it's hard to make sure of the effect. Yeah, precisely. So maybe that's something that a clever study design from somebody else in the future might be able to unfold better than we did.

Speaker 1:
[12:47] Is there a different suite of species that you encounter when you are listening back to the audio moth data, as opposed to what you encounter when you are doing any of the other work with the playback or with the sort of control, just walking through the woods?

Speaker 2:
[13:01] Absolutely. There are strong differences among all three approaches. Like for example, the best way to detect owls is to put out audio moths because we're doing these transects shortly after sunrise for a couple of hours. Yeah, we're not going to hear owls vocalizing, but if you leave the moths there overnight for two nights, they will pick them up. So similarly, but we're in the inverse direction. The moths are never going to pick up something like a turkey vulture, which is a very common bird. But how many times have you heard a turkey vulture vocalize? So you have to go disturb them at their nest or something. Yeah, I can't know if I ever have to be completely honest. Yeah, exactly. So these approaches each have their strengths and weaknesses in terms of which birds you detected relatively higher or relatively lower frequencies. It can be a little bit challenging to compare them all directly too because audiomoth data is just presence absence, whereas transect data is continuous, it's on a numerical scale. So you have to toss around some fancy statistics, Gower dissimilarity matrices and so forth, and see what you can tease out of that. But that does also complicate the interpretation, I think too.

Speaker 1:
[14:05] So when you're thinking about potentially doing other work on maybe some of these study species, do you think that there are studies that you could potentially do where it would be beneficial to do a mop transect versus an ARU audiomoth transect?

Speaker 2:
[14:22] That's an interesting question. As specifically compared to ARU transects in general, those are going to miss tricky vultures. It's not to say that tricky vultures love mob tape, but if you're doing a normal transect with mob tape, you will probably see more tricky vultures. So there are situations like that. I think though the area of research where mob might be the most effective as a tool, doesn't have to do just with counting birds per se, but involves specifically studying their reactions to mobs. The amount of creative work that has been done in that domain so far I think is really phenomenal. So if folks are interested in using mob as a research tool, that approach would definitely I think be the most valuable one. One study that leaps to mind for me, that also can help possibly explain why in many situations, mob tape is just not going to be an effective way of showing you birds, was done in Europe a few years ago, not too long ago, on common chaffinches, a common feeder bird in much of Europe, and their responses to mobs. So in that species, males often respond more intensely than females do, but not during the period when females are fertile just before laying in incubation. At that time, male chaffinches don't care about mobs in the slightest. All they're interested in doing is guarding their mates to make sure that they have the maximum chance of being the father of any eggs they might be involved in rearing subsequently. So there's this couple of week period when female chaffinches are starting to lay eggs, when male chaffinches just don't care about mobs. That's such an interesting finding. I feel like there might be scope to discover more unusual things like that in different systems throughout the world that can tell us more about how mob forms a part of birds' lives specifically. That's such an appealing, interesting kind of question to me, even more than seeing what birds, birders may or may not detect with these various methods.

Speaker 1:
[16:12] Yeah, it's interesting you point that out, because that does track with a lot of birders' experiences with using mob tape in whatever circumstances. There are times of year where it just does not work. You can play a mob in the woods and get very little feedback. You might get a chickadee, a titmice, a gnat catcher, some of the more common or more responsive birds to those sorts of audio tracks. But it doesn't work in the summer all that much. Consequently, it does seem to work the most when you're getting these mixed species flocks moving together in the late fall, throughout the winter months, at least where I live.

Speaker 2:
[16:51] Yeah, that's an interesting observation. For sure, I feel like different birders' mileage may vary in that respect pretty strongly. Because I think Peter Pyle in his article was finding something in a somewhat different direction, at least. He was thinking that maybe migrants and vegans in particular can be some of the birds least inclined to respond to mobs, which at least logically makes sense. Like you'd think if a bird is just passing through, especially if it's conceivably not where it's expected to be, it might feel the least investment in the act of responding to a mob. Because mob response is likely something that's pretty costly for birds, or at least it has the potential to be. Aside from the energetic costs, in theory, the birds would also consider the risk of being eaten by a predator, which is pretty substantial. So yeah, it's really interesting to tease apart why in different situations at different times of year, different guilds of birds may be more or less inclined to respond. But it's true, there are many situations where pretty much nothing is going to come in.

Speaker 1:
[17:51] Yeah. You obviously use it for research. Do you use this tape in your normal birding? Are there circumstances that you feel are more appropriate perhaps for it than others?

Speaker 2:
[18:04] For sure. Yeah. I think it really varies extremely strongly, depending on the circumstances you're in specifically. So in addition to our research program at Jasper Ridge Biological Preserve, for example, we have another auxiliary research program at Tomcat Ranch, which is a ranch owned by the now California gubernatorial candidate, Tom Steyer, who wants to learn about the birds on his ranch. And so we used mob tape. We did a very similar system to the one that we had going at Jasper Ridge to examine the birds there with audio moths, normal transects, and mob tape. But in general, I think it's for each birder to make for themselves that the calculus of whether mob tape is something that's going to be acceptable or not in your particular situation. And personally for me, I found the process of permitting for Jasper Ridge to be really helpful in thinking through exactly what their key requirements are for any given situation. And so, yeah, there are lots of resources out there, you know, local Audubon societies and so forth. They might have guidelines on playback in general and potentially even nowadays, I suppose, on electronic pitching in particular, to help, you know, folks think through exactly whether what you might be doing with mob tape is going to be worth the potential cost to the birch that you'll be encountering.

Speaker 1:
[19:17] Is the juice worth the squeeze, I suppose?

Speaker 2:
[19:19] Precisely.

Speaker 1:
[19:20] It is heartening to think about the permitting process. I thought that was particularly interesting. I imagine that it's pretty, I don't want to say excessive. I imagine it's especially thorough. Maybe that's the better word for it. When we think about how...

Speaker 2:
[19:34] It's a very, very diplomatic approach.

Speaker 1:
[19:35] Yeah, but when we're doing research on it, we want to make sure all our bases are covered for this sort of thing, where I think a lot of like kind of lay birders out there in the field pulling up a mob tape on their phone. Tape, it's not even a tape anymore, it's just a file on their phone. And using it, don't always ask those questions. What kind of questions did you find in the process that you found were particularly insightful into the impacts on, potential impacts on birds that you're studying or observing?

Speaker 2:
[20:04] That's a great question. You know, one general takeaway was that a bunch of the questions that came up during this process, I just didn't really feel that equipped to answer. Like, you know, what exactly is the energetic cost of a mobbing session for a bird?

Speaker 1:
[20:16] That's a question you tried to answer.

Speaker 2:
[20:17] I have no clue. Yeah. And so, you know, major gaps like that one, I think, can give you some opportunities to pause and think. And you're like, if I really have no clue what the effect is for the bird, maybe that should tend to make you more on the precautionary side of things potentially. And another, you know, similar kind of paradigm, you know, that came up during the same process was trying to explain exactly what mob tape is in a very kind of precise way to folks who might not be birders even, and certainly not familiar with the practice. And so the best way I came up with, you know, to explain it in this context is to anthropomorphize quite a bit and say, it's basically like playing a recording of a whole bunch of people screaming urgently or maybe yelling cuss words or whatever. You know, that's basically what mob is for birds. So if you put yourself in the position of a bird and, you know, you hear a bunch of other people yelling, screaming and cursing a ways over there, that's going to be a pretty remarkable process, you know, even though it is something that happens to birds in the wild every so often. Just thinking about it in that way kind of does get the picture across to people, that it's something that could potentially be fairly stressful. And so, you know, not to say that it's one of the top three causes of avian declines or anything along those lines, as Peter was saying, you know, fossil fuel emissions, whatever. You can certainly think of things that are going to be worse for birds. But yeah, considering how little we know and how from a human perspective, if people played mom tapes for humans, good heavens, imagine that, that'd be terrible. And so those sorts of trains of thought just can kind of get you thinking about exactly them. Making sure that whatever the benefits you're looking for are really concrete and pretty, they better be pretty awesome.

Speaker 1:
[21:59] That's an interesting question, because when I think about the human impact, they did like someone playing a tape of humans overreacting, perhaps to us, not over just reacting in a natural way, in a fearful and an intense way to a different situation. It's almost like I would, I would react differently based on where I was. If I were out in the field, you know, birding in a public park or something, someone kind of away from everybody, I would react differently than I would like say, on the streets of a major city where I hear a commotion. Like it's, I wonder if birds do the same thing too. It stands to reason that they might.

Speaker 2:
[22:36] Absolutely. It really does. You know, at the same time though, how do you know whether you're in a public park for birds or, you know, a quiet residential street? And so, yeah, you know, having that sort of, you know, lack of knowledge about exactly what the precise neighborhood context is for a bird is, is kind of gets back to the same thing we talked about a moment ago of how it's just so hard to piece together every element of the calculus for a bird in a given situation to make sure you're making the right decision.

Speaker 1:
[23:04] Continuing on this, this analogy, also, you know, if I were in a situation where I'm constantly hearing that sort of thing, I would eventually ignore it. And you, you bring up the point that birds can get mobbed out in certain situations. Like, is that good for birds? I don't know. Probably not.

Speaker 2:
[23:20] Yeah.

Speaker 1:
[23:20] Like they, you know, urgency response does have a purpose. Yeah.

Speaker 2:
[23:24] Yeah. You'd really think so. At least it exists in so many birds with, you know, such diverse evolutionary histories and so on. It seems, and you know, it exists outside of birds too, like, you know, sea lions mob great white sharks off of South Africa and so forth. And so it's a very widespread process. And I tend to agree with you that in cases where it gets, you know, deadened by repeated use of mob tapes, that strikes me as a potentially worrisome thing. Although, you know, for example, in the places where we've studied, tried to study mob in a small way, we haven't had that problem because of the limited, you know, frequency. But yeah, you know, you can think of it as potentially bad for the birds and that it might dull the response to real predators. Also, just kind of practical points aside, there's this focal signal for cooperation among all these different bird species that seems to have been around likely for millions and millions of years. And the idea that a number of people with JBL speakers can just more or less wipe it out in a short period of time is intuitively just a little bit disturbing. And so in cases like parts of San Francisco or Monterey, here in the central California coast, where mob out, as I call it, is becoming a thing, those are a little concerning to me for sure. And then additionally, you have this interesting kind of tragedy of the commons type aspect to it, where likely one person mobbing it at very low frequencies could be a little less likely to contribute to that sort of process. But the more people go and make their own mob tapes or pick up on other people's mob tapes or whatever and potentially visit the same places, even if each of them thinks they're making a responsible decision, mobbing at low frequency individually, collectively, the effect can still probably be pretty profound, which is just yet another thing to bear in mind in terms of this kind of approach. There are just so many things to get hung up on, which is just how it is with playback in general. Since mob tape is playback on steroids, I think it applies in particular in this kind of circumstance too.

Speaker 1:
[25:23] I'm going to turn just a little bit here because you sent along a really fascinating article in our original conversation about superb lyrebirds, famously a species of bird that is known for its incredible ability to mimic just about anything. I think we've all seen the David Attenborough, Life of Birds scene where they mimic your chainsaws and camera shutters. But naturally, they're around a lot of bird songs and they mimic mob tapes. They're not tapes, but they're equivalent to mob tapes. The study that you sent me had this amazing video that I, honestly, I was watching like slack-jawed, and I'll include it in the show notes because I think it's relevant. But of these lyrebirds, they're basically using mobbing bird behavior in their display behavior. The male is using this to display the female's. Incredible stuff. Does it have the same effect on those local birds as it does on the local group of chickadees and titmice I might have in the park down the street?

Speaker 2:
[26:25] What a truly phenomenal question. Yeah, that's, so first of all, I want to think that study is so amazingly awesome. It's one of the coolest bird behavior studies out there to my thinking. But yeah, that's an amazing perspective on it too. I think that the male lyrebirds, they seem to be using this imitation of a mobbing chorus, as the authors describe it, to lure back in females who are starting to lose interest in their displays. Which is like-

Speaker 1:
[26:51] So nefarious.

Speaker 2:
[26:52] Exactly. There's Machiavellian lyrebirds out there. But once they trick the females to come back in and help drive away the imaginary predator, oh, they're back at the court. Here we go. We're just playing again. Yeah. Second chance of the first impression, precisely, if it didn't work the first time. There's a very specific target audience, which is that one female, and if she comes back or doesn't come back in a short span of time, probably the mob use isn't going to go on too long. It does appear that some other local birds respond to the mob, the mobbing sounds, which is a testament to the amazing vocal mimicry abilities of lyrebirds. Yeah. But I tend to think that likely the goal is so circumscribed. So cleanly, narrowly, clear cut, that it's not going to be as broad and general an effect on the other birds, perhaps as what birders could use mob tape for, which is trying to attract all the birds for a long period of time. But that's an amazing question. And folks down in Australia should definitely look into it further to see whether these lyrebirds are in fact breaking the ABA code of ethics.

Speaker 1:
[27:55] Someone needs to get on them. So just to like, this is not related to our conversation on mobbing. This is mostly just a statement as to the incredible nature of these lyrebirds. The fact that they can manipulate the species in their mobbing behavior, incredible stuff. They can choose which way. They're making their own mob tapes in their heads and their syrinx.

Speaker 2:
[28:18] But you know, maybe even better equivalents than mob tapes for this lyrebird behavior, could be fishing because that's what people do when fishing. Because you can make different scold sounds that resemble different birds. So yeah, lyrebirds are really gifted fishers. They're doing this without the aid of MP3s and JBL speakers and all that. It's just your own, what you have to work with.

Speaker 1:
[28:42] So do you draw a distinction between mob tapes and fishing?

Speaker 2:
[28:47] I think, just in terms of mob tapes being potentially an easier way to broadcast really loud sound through a loud area for a long time.

Speaker 1:
[28:56] Persistent.

Speaker 2:
[28:57] Without tiring you out or anything. Mob tapes certainly has a potential to have a bigger effect than fishing. But then again, ultimately, it's, I suppose, appealing to the fairly similar instinct in birds, which is the response to potential predator alert calls. People are so good at fishing that the effect is possibly somewhat reduced. But for most mere mortal birders, probably fishing is going to be likely a somewhat less dramatic way of inducing a somewhat similar effect. Yeah.

Speaker 1:
[29:27] I'm going to ask the big question here. Knowing full well that you can't really answer it. But just to test your informed opinion on this, do mob tapes have a negative impact on birds? Does it cause you to hesitate of your own personal use, if you use them at all?

Speaker 2:
[29:52] I think one thing that we can say pretty confidently is, they don't have a positive effect on birds. Like it is just very challenging for me to think of any way in which mob tape use is a definitively good thing. They do seem to have some effect. Potentially, I think in many contexts, it is again super situation dependent, but likely mob tape is going to be exerting at least some cost for birds most of the time. As Peter says in his article, it may not be the biggest cost that a single bird could potentially exert on birds, but it ain't exactly helping them out either. That being the case, I think putting yourself through your own permitting process in any situation where you're considering using mob tape is just a great approach. The outcome of that process depends on you and your ethical views and your practical circumstances and what have you. There might be some situations where you decide that mob tape is just not worth the squeeze, in fact, and others where you make the calculation that maybe you're going to go discover a liar bird situation here in North America. Like, can mockingbirds imitate moms to bring in females?

Speaker 1:
[31:00] I would put it past him.

Speaker 2:
[31:01] Yeah, somebody might have heard it already, but you could identify a different research question, like challenges and make guarding and mob tape and then what have you. Or some folks in Brazil recently did a study looking at how males might use bravado at moms to impress females with their daring, which is a fascinating concept too. If you can think of a really clear rationale like that one and you've done your due diligence in terms of considering in your informed way, in your specific context, the potential negative effects, that might be a different situation. But by and large, I think mob has the potential to reduce this and deaden this focal signal that's been going on for millions of years through mob at, as we've discussed, and potentially cause other stress situations for birds. And so as Peter's conclusion about the breeding season and how potentially mob use might be something you want to minimize at that time of year, I think is just a generally good baseline at least that you can build on or adjust depending on the context.

Speaker 1:
[31:59] Yeah, it reminds me very much of the sort of playback discussion that birders have been having for decades. Ever since playback became easily accessible in your pocket for the most part. I think mobbing is particularly interesting because as we kind of talked about in a discussion that I had on the podcast with a couple other people, it does affect a much wider swath of birds. Playback is intended to attract one species, and frequently one individual of that species, whereas mob, the whole point of it is to attract as many birds as possible and pull them away and bring them close. I can see situations where it would be, I don't want to say beneficial, but useful to use that if you're leading a large group and you want these people to have a really great experience getting a good look at some birds. Mob is effective for that sort of thing. But I do think you need to be aware of the impacts. That's my personal take on it.

Speaker 2:
[32:55] A hundred percent, could not agree more. One thing to bear in mind when doing, not that this is necessarily the most frequent context, but if you're out there looking at birds for an e-bird checklist or something that ideally is getting a fairly balanced picture of the birds in an area, mob will pull in some birds and potentially repel some other birds. So you get a very different looking picture than you might otherwise. So it's like, for example, the species with the strongest effects of mob versus transect. In our studies here in the past year or so, where scrub jays, for example, go way up when you use mob tape because scrub jays are pugnacious birds who love going to cuss at predators. Exactly. Buick's wrens and oak tips are some other species that respond very strongly. With the most statistically credible differences between mob transects and non-mob transects, then they're going to be plenty of other birds where the difference is negligible or even negative. You might even potentially see fewer of certain things while using mob. So it's true that it's going to net you more of some birds, but only some birds and those birds may or may not be the ones that you're most interested in looking at in a given context too. Scrub jays rock, but I'm not sure if that's the most common goal for birders going out for a day, is looking at a whole bunch of angry jays.

Speaker 1:
[34:05] Not hard to see without mob. Yeah, the scientists in you, you mentioned eBird checklist. Do you think that mob versus no mob affects an eBird checklist in such a way that it should be noted in the checklist and the Cornell should maybe come up with some sort of computational mathematics sort of thing.

Speaker 2:
[34:28] Oh, like a protocol, like traveling or historical or mob.

Speaker 1:
[34:30] Exactly, exactly. For that, because does it skew the data? Enough.

Speaker 2:
[34:36] That's such an interesting question. I think that depends on what exactly the question you're looking to use the data to investigate is.

Speaker 1:
[34:42] Fair enough.

Speaker 2:
[34:43] And so for some studies, it may or may not be relevant and so forth. But in general, this may be possibly a clouded perspective, but I worry that potentially including an explicit protocol option about mob might be the kind of thing that leads birders to be like, oh, let's do one traveling checklist, one mob checklist, what have you, which in certain cases could be something worrisome, especially in areas with higher birder density or what have you. And so that may be a paranoid overreaction from somebody who spent a fair amount of time thinking about mob. I can't tell how real that possibility is or whether it's something we should worry about.

Speaker 1:
[35:21] No, I think you're right. I think you're right. It would encourage that sort of behavior, which is not the sort of behavior we necessarily want to encourage.

Speaker 2:
[35:28] But then again, I can totally imagine situations where researchers would have their conclusions tangled up by including mob and non-mob.

Speaker 1:
[35:36] Yeah.

Speaker 2:
[35:36] You know, checklists in the same data set.

Speaker 1:
[35:38] Yeah.

Speaker 2:
[35:39] All right.

Speaker 1:
[35:40] Great. Great conversation. Thank you so much. Marty Freeland is a researcher at Stanford University. I will put a link to the lab that he's part of in the show notes, so you can check out all the great work they're doing. And of course, a link to the Peter Pyle article that was recently published in Birding Magazine and online. If you haven't checked it out, please do it. It's great. Peter's great. Marty's work is great. It's a fun article. Marty, thank you so much for your time. What a fun conversation. And I look forward to seeing where you go with this research, because I think there are some more questions out there. Can't wait to see it published and then we can discuss it even further.

Speaker 2:
[36:18] Thank you so much. It's great to talk with you. I would like to give a super quick shout out to the staff at Jasperage who kindly helped make all this work. Adriana Hernandez, Trevor Hebert and Jorge Ramos, as well as my collaborator, Mya Shu, who helped do a whole bunch of the surveys as well. So it's always a team effort to answer any other complicated question.

Speaker 1:
[36:35] Absolutely. Thank you so much, Marty.

Speaker 2:
[36:37] Thank you, Nate.

Speaker 1:
[36:39] The American Birding Podcast is brought to you by the American Birding Association. The ABA is of course a membership organization. The best way to support it is to become a member. You get access to our fantastic magazines, all of our online resources, plus great discounts to our partners like Zeiss OM System and BDO Books. If you join or renew before May 31st of this year, you will help unlock an additional $100 per member for the ABA. You can learn more about all the benefits of membership in addition to helping support all of our free resources like this podcast, like What's the Spurred Live at aba.org/join. Special shout outs this week to Will Condit of St. Louis, Missouri, John Farnsworth and family of LaConner, Washington, Angela Jones of San Anselmo, California, Peter Keyes and family of Portland, Oregon, Ernest, Pensierra and the Pensierra family of Cranston, Rhode Island and Sarah Ruiz of Austin, Texas. All of them recently joined the ABA and noted this podcast as a reason for doing so. Thank you so much and welcome to the ABA. Executive Director of the ABA and Executive Producer of this podcast is Wayne Klagner, who tries to avoid discussing electronic pitching with non-birds because it might be confused with some groundbreaking treatment for incontinence. Technical production is by John Lowry, who was disappointed that his custom-built hawk cannon had to remain on the shelf in his garage yet again. He's listening Marty if you need him. Additional help comes from Maggie Fitzgibbon, Frank Izagiri and Greg Neese, whose custom-made Chicago mob tapes have never attracted a single bird, but were instrumental for putting Big Jim Colissimo in the North Side Gang behind bars. You can find us online at aba.org. On social media, most everywhere is American Birding Association. On Blue Sky, we are at ABA Birds. Questions, comments and hot takes for the live show can come to podcast at aba.org. I'm Nate Swick. Thanks for listening. Bird Like Tom, we'll be back next week.