BLM uses acoustic bird monitoring to learn more about bank swallows in Alaska

Azure Hall: Hi friends and welcome back to the BLM’s On the Ground podcast. My name is Azure Hall, and I'm joining you from the Alaska State Office and today, we're talking bird sounds.

Joining us today is a BLM wildlife biologist here to share some details about a very exciting project going on in Balam, Alaska, funded by the Bipartisan Infrastructure Law. Erin, can you tell us a little bit about yourself?

Erin Julianus: Yeah. So hi, Azure. My name is Erin Julianus and I'm a wildlife biologist with the BLM working in Fairbanks, AK. I work for the Central Yukon Field Office, which is the field office that manages the Dalton Highway utility corridor.

Hall: Thank you so much, Erin. So today we are chatting about acoustic bird monitoring. Can you give our listeners an idea of what exactly that is?

Julianus: Yeah, for sure. So acoustic bird monitoring, I guess it's not confined to just monitoring, you know, bird sounds, but it's using audio recording equipment which we called automated recording units, or I might say ARU's in the interview, but to collect wildlife sound data or acoustic data. And this data in this case is bird songs and calls and it can be used to do it has all sorts of different applications. It can, you know, be used in animal behavior studies or to monitor and inform, you know, species conservation or to conduct wildlife inventory work and for us. As you know, the BLM, we are using it to better inform our environmental analysis for our permitted activity.

Hall: Very cool. So, what exactly was going on in this project area that led us to use this technology?

Julianus: Yeah. So, like I said, you know, we do a lot of our field office manages the BLM lands in the Dalton Highway utility corridor, which north of the, I guess runs from north of the Yukon River to Prudhoe Bay and in that utility corridor, you know, to maintain the road and to maintain the Trans Alaska pipeline we have a number of mineral material sites or gravel pits that we that we permit some get a lot of use, some don't get very much use at all. But what these pits do is they can they have the potential of creating artificial habitat, nesting habitat for bank swallows.

Hall: So, in terms of creating an artificial habitat, what would lead the bank swallows to choose gravel pits for their homes?

Julianus: So, bank swallows, as their name suggests, they excavate burrows in and nest in loosely aggregated bank material that is in interior Alaska and elsewhere. It's naturally found along large river systems, and they'll also take advantage of similar habitat in these in these gravel stockpiles, and they have, I don't know, maybe a fairly narrow margin of what suitable material is and it has a lot to do with the tightness of the material and the slope is a big part of that. But yeah, their natural habitat is riverbanks in interior Alaska. But at the northern extent of their range, you know, I think that that artificial habitat along the Dalton Highway is yeah, kind of important for them.

Hall: And so, for my understanding, there is a bit of an overlap between construction season and nesting season.

Julianus: Nesting season for migratory birds in Alaska is really short, you know, because we have a short summer. And similarly, we have a really short construction season when you know the bulk of the road maintenance and other construction projects occurs. So, a lot of overlap between those two, two things which creates the potential for conflict.

Hall: Conflict, tell me more about that.

Julianus: It kind of created this this situation where we had banks follows burrowing and nesting in material stockpiles that the Department of Transportation and you know other permittees wanted and needed to use for maintenance of the road and the pipeline, we had kind of a resource conflict that needed to be addressed.

Hall: So, in the face of this resource conflict, how does acoustic bird monitoring lead the BLM towards a solution?

Julianus: Yeah. So, we have a general, a general sense of of the phonology of these birds. You know, the timing of all the important parts of their life cycle when they, you know, first arrive on the on the breeding grounds. And when they kind of initiate nesting, then the core of their nesting season is. And then when they fledge and then when they leave. We have these general blocks of time for bank swallows and other species, but in this situation, we needed more specific information about, you know, when exactly they arrive and when exactly they start using the stockpiles or, you know could potentially start using suitable stockpiles and likewise when they leave, when they're done using when they're done using them for the year. So, you know it's easy enough to say well, we can just go out and do surveys, but the northernmost gravel pit. I think that the BLM manages is almost 400 miles away. It’s kind of a day's worth of driving to get to a lot of these sites, no matter how you look at it. So, it's hard to pinpoint exact days when birds are showing up and when birds are nesting. And then when the birds have fledged so you know there's, I would say there's no substitute for actually getting out there and getting on the ground, but this technology is really helping us get that more specific information because we can't be everywhere at once and we can't, we don't necessarily know what day we need to be there, you know, to do to do field based surveys. So yeah, this is this technology allows us to get a lot of data for multiple different sites and really hone in on a lot of that timing stuff.

Hall: And the BLM isn't doing this important work alone. There's a very cool partnership going on within this project with the Institute for Bird populations. Can you share a little bit about how that's worked?

Julianus: Yep, yeah. So, the Institute for bird populations, or IBP, is a really cool nonprofit organization that I didn't know about prior to prior to their partnership with BLM on this project. But they're based in Central California, San Francisco area, and they're work really focuses, as their name implies, on evaluating changes and monitoring bird populations, and they really collaborate extensively with national and international government agencies, including the BLM, to conduct this research. So, we, BLM Alaska has a multi-year agreement with IBP that began in 2022 and yeah, the researchers have a lot of experience working with the acoustic data and we've been interested in using this data to support, you know, the reviews that we're required to do, the environmental reviews required to do by law. So the Bank Swallow Project is the first project we've really worked on with IBP, but there's definitely the potential and interest in expanding it to, you know, different BLM, you know, management issues across the state.

Hall: And along with a short nesting and short construction season, there are also some restrictions coming from the Migratory Bird Treaty Act.

Julianus: There's been bank swallows in a handful of pits, 3 or 4 pits that we've known about for a long time. And they're these established colonies, there are these really cool colonies. That's really neat to go watch them during the nesting season, you know, foraging outside the outside, the colonies. But we've known about these colonies for a long time. And it's always just been kind of a chronic issue. We know that they're nesting. We know that they're, you know, actively nesting, and we're required to comply with the Migratory Bird Treaty Act which in part, you know, is part of the, I guess, implementation of that in Alaska. Our policy says that we're not allowed to, or activities are not allowed to disturb active nests or nest sites between May 1st and July 15th. So, we kind of have that timing limitation that if there's an active colony of banks follows basically the stockpile is off limits for that for that chunk of time. So, these established colonies it's just kind of an issue year after year where they're active and they're going to be off limits to extraction until July 15th.

Hall: So, keeping in mind that we are still in the beginning stages of our monitoring, have we gathered any interesting data yet?

Julianus: Uh, let's see. So, we definitely found, you know I said that there, there are three or four really established known colonies that we've known about, but the sound monitors have detected banks swallows up more sites than we originally thought. I think it's 13 sites so far based on last field season. And you know, that may not mean that they're established colonies, but that they are, you know, in fact there and maybe they're there at the beginning of the season kind of scouting things out and then they move on or something else. But it's neat to see that, yeah, there are bank swallows on the recorders at more than just those, those few sites. The Dalton Highway is it's really this this long you know multi-100-mile NW transect and it goes through the transect, goes the road, goes through basically the northern extent of the bank swallows’ range. So, I think that that's, you know, scientifically pretty interesting, you know, to see the timing of arrival of these birds and all the other species, you know, for that matter, that are picked up on the on the units. But it's just a really neat opportunity to, yeah, see when these birds arrive and how that differs from their arrival times in more southernly sites.

Hall: Absolutely. I'm excited to see what comes next for the project. Can you give us an idea of what the longevity looks like?

Julianus: Yeah. So, I think that we will probably it's to be determined, but I think we'll probably collect data for at least one more year. It would be nice to get 2 full field seasons to get the arrival times and the departure times, and then you know, as I said, this is a statewide agreement. And yeah, I think there's a lot of potential to apply this technology to other permitting that we do. I know that we've talked a lot about using these monitors. Yeah, this equipment, this technology in things like prescribe burn efforts where we're trying to figure out when we can do prescribed burning and interior Alaska and minimize the impacts on migratory nesting migratory birds. So, I think that there's a lot of applications that we've been talking about internally.

Hall: So, we are closing out our first field season with some promising data points. We're looking forward to next season, but in between those two things, what is going to be going on with this project? Are you analyzing data now?

Julianus: Yeah. So fortunately, I won't be doing the data analysis. Yeah, like I said, they've got some really good people that are really experienced working with that software, it's all software based, so they'll go through all the data from this year. And yeah, they'll publish an interim report. And, you know, I think from that data from the data from this year and part of last year, I think we'll be able to look at those dates and see whether we can shorten the timing limitation or adjust it even a little bit. You know, even if it was adjusted or shortened by a week, you know I think that that would improve the flexibility of using these mineral material sites or these gravel pits for you. Know what they're kind of legally designated to be used for, which is to support the maintenance of the Dalton Highway.

Hall: Absolutely. It sounds like there's still quite a bit of work to be done, but there's also a lot to be excited about in such a short time frame. I really appreciate you taking the time to come and share all of this with us, Erin. It's such a fascinating project, such an exciting partnership, and I can't wait to see what comes next and to our listeners. Thank you so much for joining us and spending some time learning about acoustic bird monitoring. If you're interested in learning more, I would encourage you to check out the resources attached to this episode and we will see you next time, on the ground.