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There’s something uniquely thrilling about a cross-country road trip—especially when someone else is paying for the gas. But to spend time on the road with a friend, sharing new experiences and making new memories while also breaking new ground in the study of bird migration? Sign us up. 

That’s exactly how Madison Bygrove and Natalie Emerick, graduate students at the University of Windsor in Canada, have spent their spring. On April 13 they flew from Ontario to Vancouver, rented a van, and set out on a continent-spanning journey they expect to complete next week. The purpose of the trip is to install 100 audio recorders, spread across southern Canada to form “an acoustic net that catches birds,” says Dan Mennill, the professor of ornithology advising the duo and overseeing the work. 

The project is called , an expansion of the innovative Motus Wildlife Tracking System launched in 2014 by Birds Canada and partners. To date the collaborative international network has focused on birds outfitted with tiny tracking devices: Radio receiver towers gather data on any tagged bird that flies near them, providing scientists with a digital record of avian movements. The new effort broadens the scope of Motus with recorders that can detect not only tagged individuals but any bird that passes by. The devices Bygrove and Emerick are setting up record the nocturnal flight calls that migratory birds use to communicate with one another. Mennill and his team use machine-learning tools to identify the recorded species (and later verify the IDs themselves). He plans to eventually set up 300 of them.

̽����ѡ noticed about the project and reached out to learn more. We caught up with the three over Zoom, while Mennill was in Petit Rocher, New Brunswick, and Bygrove and Emerick were stopping over at home in Windsor, Ontario, before the second leg of their trip. The following conversation, recorded on May 19, has been edited for length and clarity. 

̽����ѡ: What’s the goal of this project? What are you hoping to find out?

Dan Mennill: We have been studying flight calls for about 15 years because we saw the potential for these quiet sounds that birds make in migration to allow us to gain new insight into migratory biology and the population health of birds in North America. These quiet sounds that birds produce while they’re on the wing, moving through the night sky without the aid of great visual cues, are really important for birds in navigation and flock cohesion, but they also give us a tool, if we just point microphones upwards, to try to study which species of birds are moving overhead. 

Madison Bygrove: This project also works with citizen science, so we get to incorporate different landowners and different schools and businesses and conservation centers to put up these recorders. It’s really exciting to meet everybody and have a collaborative network of recorders across the country.

Natalie Emerick: I think what makes it special, too, is that we could also give back to these community science volunteers by not just coming in and asking to use their land to get data. We’re able to publicly display the findings that we have on , and that’s for the homeowners and the people in the nature centers that we set up with. But anybody who’s interested can log on and see all the detections.

Mennill: It’s the springtime right now. We’re catching the birds as they fly from their overwintering areas, and it doesn’t matter which part of Canada they’re heading north to, because Madison and Natalie 35 days ago flew to Vancouver, and they’ve been launching recorders all the way across the country. The vision is a coast-to-coast set of microphones that can catch every bird that flies north in the springtime and south in the fall and provide us with a new migration-monitoring tool.

̽����ѡ: Tell me about the technology you’re using—it’s different from what we typically think of when we hear about Motus.

Mennill: The business of radio-tagging birds and putting those special Motus tags on them has revolutionized our understanding of bird migration. It’s so important because it allows us to track those birds’ migratory routes. One challenge of the Motus project is that only 1 percent of 1 percent of 1 percent of all the birds in the world can be caught and tagged. It’s just a tremendously time-intensive and costly endeavor. 

The thing about flight calls, by contrast, is that you record every bird that calls as it flies through the night sky. The idea is that we can combine the traditional Motus telemetry system with a new microphone bioacoustic system, so that every Motus tower or every backyard recorder can tell us not just about the birds that are radio tagged, but every single animal. There’s a network of ornithologists across Canada who work with each other to fund the Motus project, and about two years ago, we decided we should expand Motus towers to include this bioacoustic technique for tracking birds. It’s the next generation of Motus. 

̽����ѡ: How did you decide where you should install all those microphones?

Emerick: We began by centering the . These are banding stations all across the country, and many of them have Motus towers. When you think of a cross-country trip, it can be a little daunting to figure out what route you’re going to take, especially when you don’t know people in the middle of the country. But from there, we have a really interesting combination of people who are really excited about birds, people who are ornithologists. And either we’re setting up in their backyards, or nature centers they’re associated with, or other sorts of organizations. But we also have a cool sector of people who really know nothing about these things, that they’re either friends of ours, or friends of friends, or they heard about it from someone else, and they happened to be in a location that we were trying to fill, and somebody recommended them to us. So those people are really interesting because we get the opportunity to introduce them to this sort of community science and let them be a part of it and learn about it for the first time without them having any prior knowledge about Motus or migratory birds. 

Bygrove: We tried to stay along the border of Canada and the U.S., but it didn’t always work out that way. We were kind of opportunistic with the sites that we could get.

Mennill: But even your most far north one isn’t very far north, when you think how gigantic Canada is. And you know, therein lies the excitement of the Motus Audio project. I draw the analogy of a bouncer at a bar. It’d be really hard to count everybody in the bar quickly, but if you’re sitting there taking a clicker every time someone crosses the threshold, you can gain a very accurate count of how many people have entered. We are that bouncer, and our microphones are the clicker to get these birds as they enter Canada.

̽����ѡ: What do these recorders look like, and what does each installation involve?

Bygrove: They’re two little boxes, maybe like 16-by-16 centimeter cubes, and the top one has a microphone in it, a little , and there’s a on the top to help funnel those calls into the microphone. And then that runs with a little cord into the next box, which has our little mini computer, which has all of the software on it, telling the recorder when to record, and telling it also to upload these files over wifi to our dashboard. So it’s pretty small, which is really helpful when you’re trying to transport this many across the country and set them all up. We couldn’t fit a Motus antenna in the back of our van. 

Mennill: That’s all it takes! It’s this one little night-sky-oriented microphone that does the trick.

Emerick: A lot of people are surprised at how compact it is compared to the Motus towers. It really is just the two boxes, and usually we just drill it to a post and either free-stand it or attach it to someone’s fence.

̽����ѡ: So what’s been happening since you flew to Vancouver?

Emerick: We set up our first one on April 15th, on Vancouver Island. We spent a few days over there, we set up six recorders on Vancouver Island. You caught us at our intermission, is what we like to call it, between our west leg and the East Coast. We made our way through British Columbia and then started making our way east from there, and we’ve set up several in each province so far, trying to keep it sort of equidistant, like a fence. After this interview, we’re going to restock the van and start heading out East to set up all our recorders along every province. Except for Newfoundland, sadly, because it’s a little out of the way for us.

Mennill: But our Birds Canada collaborators have got one up in Newfoundland, so we will hit every province.

̽����ѡ: Aside from the scientific value of this project, I’ve gotta say: It sounds like a lot of fun. 

Bygrove: It’s been so much fun. It’s both of our first time out West, so just seeing the Rockies was incredible. Like, just flying from Windsor, where it was all brown, to, Vancouver, where it was beautiful and green, and it was springtime—it was amazing. And everybody’s been so kind to us on this trip.

Emerick: We’ve traveled together before, and I feel like we both kind of come into this road trip with the same outlook, which is: We’re gonna get our work done, and we’re gonna do the research to the highest degree, but we’re also gonna have fun and be grateful. We really hadn’t seen much before this trip outside of Ontario, or a bit of New Brunswick and a bit of Quebec. So, we’ve just been having the best time, and we’ve been making the most of it.

̽����ѡ: Are you finding time to do some birding?

Emerick: Absolutely. We’ve had some really kind people—even, like, Airbnb hosts—that have pointed out some good birding spots for us. It’s funny to see how curious people are that we get so excited about the backyard birds out West, the ones that are super common that we don’t get. We saw a California Quail in someone’s backyard, and we hadn’t seen one before. They kind of walked up while we were setting up a recorder, and we were like, oh my goodness, it’s a quail! And he was kind of like, well, duh. Of course they’re here.

Mennill: You set up a recorder northwest of Calgary in someone’s yard, a community volunteer, and this machine-learning algorithm kept showing us Wilson’s Snipe, which isn’t a common animal, or an animal that any of the three of us are familiar with. And we’re like, oh, there’s clearly a glitch in our matrix. So we dug into it, and lo and behold, the volunteer’s backyard seems to be home to a display ground of a Wilson’s Snipe, and all night, every night, since Madison and Natalie were there, there’s Wilson’s Snipe calls from sunset to sunrise. So we get some things that we never would have anticipated. 

̽����ѡ: How are you traveling?

Bygrove: We’re in a big Chrysler Pacifica, a big seven-seater van to fit all of our stuff. But we’ve been staying at Airbnbs along the way, or hotels, or if anybody’s nice enough to host us at their house, we’ve had a couple nights like that, which have been super amazing. It’s great to have a home-cooked meal while you’re on the road, because you don’t get that very often.

̽����ѡ: What have been the highlights of the trip so far? Or, if there were a blooper reel, what would be on it?

Emerick: It’s actually been quite smooth. We really haven’t had too many bloopers. But in terms of highlight reels, I’ve personally been doing a one-second video every day of what we’ve been doing, just to kind of capture the sounds and the moments and our highlights of the day. In terms of birding, we stopped in at , south of Calgary, and it had, like, hundreds of avocets and Black-necked Stilts and all kinds of ducks. All the birders around there that come every day were like, ugh, nothing good today. Well, we’re in shock, we’re taking it all in. We took a day in Banff and Lake Louise. That was our first time seeing the Rockies.

Bygrove: was a highlight for both of us. They do amazing work there. They have a bunch of trained raptors and owls, and they use them to deter pigeons on different buildings, and it was just so neat. We got to meet baby Barn Owls. It was a wonderful day. It was a beautiful, beautiful place to visit. Everybody was so kind.

̽����ѡ: What have you learned so far, whether about bird migration or about how to do this work?

Mennill: We’re really learning as we go. I think we’ve been a bit shocked by how much variation there is east to west in how many flight calls we’re recording. We’ve been getting a big wave of migrants here in southern Ontario, but much more sporadic bursts of migration along the path that Madison and Natalie have traveled. So much so, to the point that we’re like, hey, wait a minute, is this thing on? Is the algorithm working? I was getting a little panicked, to be honest with you, until two nights ago, when we had this huge explosion of thrushes over where you are right now, Madison and Nat. There were 816 thrush calls recorded in one night, and really over the course of about one hour, from 2 a.m. to 3 a.m. And yet, a little bit further west, where Madison and Natalie have just come from, no thrushes.  

Emerick: I think what surprised me, too, is how different nearby recorders can get with their detections. We have some recorders that are near each other that one of them is going off like crazy, and the other is kind of lower. I have one up at my house, and Madison has one up at her house, and there are differences between ours, too, even though we only live about 10 or 15 minutes from each other. I’m curious, once we end up diving more into the data, what makes these areas that are close to each other but have different levels of detection so different.

̽����ѡ: How do you think you’ll feel when the trip is over?

Emerick: I’ll be sad. I’ll be sad. I’ll be excited to get to the next part, but I think we’re both having so much fun.

Bygrove: Yeah, it’s been so exciting. I’m not that excited to fly back home.

Mennill: And if this project continues on the trajectory we envision, we hope to have more expeditions in the future where we can take this initial 100 cross-country recorders and then start to fill in at greater density. And so even though this field trip will have to come to an end, it won’t be the final field expedition.