Ann Tanner is operating on 4 hours of sleep and exhibiting no indicators of it. On a moist June morning, she greets me with enthusiasm and a surprisingly sturdy handshake as I be a part of a gaggle of volunteers, gathered in a parking zone of Wyandotte County Lake Park in Kansas Metropolis, Kansas. Down the hill, a Prothonotary Warbler is busy defending his nesting territory, his candy music punctuating the refrain of close by birds.
Because the president of Burroughs Audubon Society of Greater Kansas City and a Johnson County K-State Extension Master Naturalist, Tanner has recruited the chicken lovers and scientists right here as a part of a five-year quest to find the migration route of Prothonotary Warblers in Kansas Metropolis. Final yr, this crew captured the warbler singing beneath us, named him “Hydrogen,” and mounted a geolocator to his again. Within the 12 months since, Hydrogen flew to South America and again. Solely he is aware of the place precisely. What he doesn’t know is that the group milling across the parking zone is plotting to seize him right now, and they won’t hand over till they’ve retrieved the valuable knowledge that he’s carrying on his little again.
The 15 members of right now’s outing embody Burroughs Audubon Society members and Johnson County Grasp Naturalists, retirees and younger professionals, ornithologists and novice birders. All of them have performed a task main as much as this morning. As soon as the required tools—mist nets, a home made Prothonotary Warbler decoy, and loudspeaker—is in place, the group steps about 30 ft away and Gabe McClain, a grasp’s scholar at Pittsburg State College in Kansas, begins taking part in Prothonotary Warbler songs on the speaker.
It doesn’t take lengthy for Hydrogen to react. “I see him!” Tanner calls out after a pair minutes. A yellow speck begins chirping aggressively on the decoy from a department above the web. He makes a swipe at his perceived intruder, flies into the web—and bounces out.
McClain continues to play the speaker. One other couple of minutes go by. He switches the recording to a distinct name, after which a shiny flash of yellow flies into the web once more. The group jumps with pleasure and waits eagerly whereas McClain extracts the chicken. He appears up, offers the group a tragic smile, and shakes his head. It’s not Hydrogen; it’s his mate.
However Hydrogen quickly reappears. A tense couple of minutes cross. Somebody calls out, “Received the male!” McClain goes over to extract Hydrogen and says, to our reduction, “Yep, he’s bought his geolocator on.” McClain holds the sensible yellow chicken with a piercing black eye as much as his fan membership. Pointing to a small, rice-sized bulb on the chicken’s rump, McClain says, “This little factor is what we’ve been after the entire time.” Working shortly to recuperate the valuable knowledge, a volunteer cuts the filament securing the geolocator to Hydrogen’s again, and shortly McClain is holding the tiny tracker that holds the secrets and techniques of his migration.
Birders in the USA usually affiliate Prothonotary Warblers with the darkish swamps of the South. Kansas Metropolis roughly marks the westernmost fringe of their vary, however that could be altering. For a minimum of the final 4 many years, Prothonotary Warblers have been shifting their vary northwest. Nobody is certain why: It could possibly be that hurricanes, drought, and wetland destruction are displacing them within the South—or it is perhaps one thing else. The crew assembled in Kansas Metropolis is a part of a world effort to search out out.
Erik Johnson, assistant professor of wildlife administration at Louisiana State College and former director of conservation science for Audubon Delta, coordinates the Prothonotary Warbler Working Group, a consortium of federal and state companies, NGOs, and universities that examine the chicken. They collaborate on large-scale research to analysis elementary questions concerning the species, like why the inhabitants is declining in some areas and rising in others, how local weather change is affecting their reproductive success, and whether their migratory flights intersect with offshore wind energy projects.
At the moment, there are extra questions than solutions, particularly across the western inhabitants. Though the western inhabitants is rising, scientists know that the species as a complete is declining, however they don’t know what’s driving both development, Johnson says. Mapping the migration of the western inhabitants may assist clarify its improve. Maybe these birds are migrating to a distinct nonbreeding habitat, taking a much less harmful path to get there, or migrating when circumstances are extra favorable. “We don’t know that till we begin exploring it,” Johnson says.
A possibility got here in 2023, when Johnson obtained a notably enthusiastic e-mail from a birder in Kansas Metropolis. It was Tanner. She needed to know the way Burroughs Audubon Society and the Johnson County Grasp Naturalist Program may take part within the working group’s migration examine. Tanner wasn’t knowledgeable ornithologist like most of Johnson’s collaborators, however he didn’t have any migration knowledge from Prothonotary Warblers breeding in Kansas. “And so I used to be like, ‘Oh, that is fascinating. Yeah, let’s see the place this goes,’” he says.
Jack Corrigan was the primary Missouri Grasp Naturalist to volunteer with the Kansas Metropolis challenge and is now the Missouri lead. To raised perceive the Kansas Metropolis Prothonotaries, I be a part of him for one in every of his nest field monitoring routes at Platte Falls Conservation Space, simply outdoors Kansas Metropolis. We splash by a foot of water into the darkish, sweet-smelling forest. It seems like a rainforest, and that’s most likely why the swamp-loving warblers have chosen to nest right here. I, too, would have been charmed, if it weren’t for the sunshine rain of mosquitoes pelting my face and neck. Corrigan’s unfazed by the insect onslaught, however he nonetheless works shortly.
After we arrive on the first field, he gently knocks on it and a yellow blur shoots out. A feminine Prothonotary Warbler lands on a shrub close by and begins calling in alarm. Corrigan opens the aspect of the field, revealing 5 grape-size white and brown eggs inside a nest of wonderful twigs and moss. He gently slides his cellphone over the nest, takes a photograph, closes the field, and leaves.
Regardless of the protocol requiring nest checks solely as soon as every week, Corrigan repeats this course of each three days. He says the chicks develop shortly and he may miss necessary developments if he got here much less usually, however I think that he’s a minimum of partly pushed by his private need to see the birds and ensure they’re okay. He worries about chicks getting sick or eaten by predators, he says.
His fears are cheap. In keeping with Johnson, solely about 40 p.c of Prothonotary Warbler nests in pure cavities reach fledging a minimum of one chicken, primarily attributable to predation and Brown-headed Cowbird nest parasitism. Because of nest bins that exclude cowbirds, predator guards, and a devoted crew of volunteers who monitor them, the Kansas Metropolis nest bins have had a whopping 80 p.c fledging charge.
“You’re performing regionally, however you’re affecting globally.
Whereas it might sound like a hobbyist’s craft challenge, constructing and putting in nest bins is a critical conservation tactic, says Johnson. “Predator-guarded bins are very properly documented to nearly double the reproductive success,” he says. They’re so efficient that they allow Prothonotary Warblers to breed in territories the place they in any other case wouldn’t. “So that you’re actually placing extra infants into the world,” he says.
For Corrigan, the examine is a chance to assist particular person Prothonotary Warblers and the species as a complete. “You’re performing regionally, however you’re affecting globally,” he tells me, after checking three extra equally moist and buggy bins. At dwelling, he’ll add his knowledge to the challenge’s database, which sends the information to NestWatch, a program run by the Cornell Lab of Ornithology that compiles nesting knowledge and makes them accessible to scientists, together with the Prothonotary Warbler Working Group. With these knowledge, scientists will have the ability to find out how Prothonotary Warblers’ reproductive success is altering over time, the way it varies by geography, and the way migration and nonbreeding habitat circumstances have an effect on it.
It’s one factor to know that you simply’re efficiently hatching and fledging new birds, however a serious query remained for Tanner: The place the heck have been they happening their southbound migrations? Tanner had heard that scientists within the Prothonotary Warbler Working Group have been utilizing geolocators to reply this query in different states and he or she needed the Kansas Metropolis crew to be part of it. With steering from Johnson, Burroughs Audubon Society bought 4 geolocators for $250 every in 2024 and recruited Andrew George and Alice Boyle, professors at Pittsburg State and Kansas State universities, respectively, to deploy them.
Kansas Metropolis was a great addition to the working group, not solely as a result of the birds there have been unstudied, but in addition due to the native military of nest field volunteers. Every geolocator is effective, so scientists solely wish to deploy them on birds that they’ve an excellent probability of recapturing. Meaning the birds must survive a yr, return to the identical place, and be relocated. By putting in predator-guarded nest bins and finding nests, volunteers present the places the place the scientists can reliably seize them. And by monitoring the bins carefully and eradicating threats, the volunteers improve the birds’ probabilities of surviving. George says he wouldn’t have the ability to put geolocators on the birds with out the volunteers’ efforts.
In 2024, they put the geolocators on 4 Prothonotary Warblers nesting of their bins. Scientists fasten geolocators to Prothonotaries with stretchable twine harnesses that don’t impede their motion. The Prothonotary Warbler Working Group discovered that harnessed geolocators weighing as much as 4 p.c of a Prothonotary’s weight had no detectable results on their return charges. Regardless of these precautions, not one of the 4 tagged warblers have been recaptured in 2025. Migration is a deadly journey, says Johnson, and solely about 40 p.c of Prothonotary Warblers are thought to outlive the spherical journey. Undaunted, George and McClain positioned new geolocators supplied by the Nationwide Audubon Society on one other six Prothonotary Warblers in 2025, together with Hydrogen. A yr later, on Might 27, 2026, one of many volunteers noticed Hydrogen and his geolocator at Wyandotte County Lake.
A couple of days after Hydrogen was recaptured and his geolocator retrieved, George downloaded the geolocator knowledge, which consisted of greater than 100,000 pairs of photo voltaic radiation and barometric strain values. The method of changing these to geocoordinates is “extremely difficult,” he tells me. Late one evening, after many hours of writing code, he produced the primary migration map of a Prothonotary Warbler from Kansas.
On October 24, 2025, Hydrogen arrived within the Division of Bolivar in northern Colombia, 47 days and roughly 2,800 miles after leaving Wyandotte County Lake. For the subsequent 168 days, Hydrogen seemingly lived within the Ciénaga Grande de Magangué, a part of the Magdalena River Valley. The ciénaga is an space of huge flooded forests that’s wealthy in wetland forest birds however being quickly cleared for agriculture. On April 9, 2026, the urge emigrate as soon as once more compelled him, and he principally retraced his path north, arriving at Wyandotte County Lake on Might 3, 2026. On his northern journey, he flew 3,000 miles in simply 24 days.
In 12 months, Hydrogen used habitat in 5 U.S. states, two Mexican states, two Honduran departments, two Nicaraguan departments, one Panamanian province, and one Colombian division.
Hydrogen’s migration reveals the complexity of full life-cycle conservation. In 12 months, Hydrogen used habitat in 5 U.S. states, two Mexican states, two Honduran departments, two Nicaraguan departments, one Panamanian province, and one Colombian division. Prothonotary Warblers rely on folks in all of them working collectively to preserve their habitat.
Kim Model, Audubon’s managing director of group constructing, sees a task for Audubon’s group chapters in that. Final December, Audubon invited Burroughs to take part in a pilot program for migratory chicken conservation. Audubon paired Burroughs with the Ciénaga de Mallorquín Ecopark in Barranquílla, Colombia, positioned in prime Prothonotary Warbler nonbreeding habitat. Via the ecopark, Barranquilla is advancing a mannequin of ecotourism that integrates conservation, tradition, and financial growth. They do that by reinvesting funds in the local people, restoring mangroves, and involving native folks within the creation of their applications.
“Past its conservation worth, the ecopark can be serving to enhance high quality of life in Barranquilla by bringing folks nearer to nature and strengthening the town’s identification as a spot that values and protects birds,” says Camilo Cardozo, Colombia nation director for Audubon. The ecopark provides an necessary instance of fairness in city conservation by partaking susceptible communities, college college students, and residents from throughout the town in a public house devoted to nature and chicken conservation, he provides.
The partnership is at present in its early stage, however Tanner says she hopes Burroughs can work with the ecopark to create extra consciousness for Prothonotary Warblers in Barranquilla and discover future collaborative monitoring alternatives.
“I believe initiatives like this give folks hope,” says Model. “And hope is what fuels motion.”
After releasing Hydrogen, the crew packs up the web and caravans to a different a part of the lake to recapture one different Prothonotary Warbler who returned with a geolocator, named “The Dude.” Though they have already got Hydrogen’s geolocator, Hydrogen is only one chicken amongst many. Amassing extra migration knowledge is important for constructing an correct understanding of the inhabitants’s migration.
This could be The Dude’s third time being caught: He was caught two years in the past as a younger chicken however was too small to hold a geolocator, then caught once more final yr when he was greater and bought his geolocator backpack. Tricking him a 3rd time could possibly be fairly difficult. The banders arrange two nets and a decoy. After a number of minutes, The Dude seems carrying a inexperienced caterpillar, however he appears to have discovered from his previous errors. For almost an hour, The Dude flutters above and across the nets however stays properly away from them. “Come on, simply go in,” says Sara Blunk, a Burroughs board member.
Ultimately, McClain and George run out of methods and determine it finest to come back again later. “I believe for my very own sanity it could be good for me to catch one other chicken,” says McClain. We drive to a few different nest bins, tag just a few extra birds—together with one who we be taught is one in every of The Dude’s chicks from final yr—and return to The Dude’s nest one hour later. The banders arrange all three of their nets and two decoys. They return to our remark spot sweating, panting, and with a barely delirious look of their eyes.
It’s now 4:15 p.m. We’ve been on the park since 9:00 a.m. It’s sizzling and humid and each inch of my pores and skin is roofed in a skinny layer of sweat. My again hurts from standing for hours, however Tanner tells me that the grass most likely has biting mites, so I can’t sit. (It seems the mites bought me in any case). A few of the volunteers have gone dwelling, however 5 are nonetheless right here. I ask them why.
Megan Summers, who took break day from work to be right here, says it’s the enjoyment of seeing different folks expertise one thing they’ve invested a lot in. Heather Cwach, a Grasp Naturalist who helped begin the nest field program, says she desires to see the validation of their efforts. Tanner sums it up: “That chicken carries our coronary heart in that GPS.”
“That chicken carries our coronary heart in that GPS.”
So we wait for one more lengthy, sweaty hour as George and McClain strive each trick they will consider. Lastly, they disappear behind bushes to test a web for the hundredth time and go quiet. One of many volunteers goes to look and returns pumping her fist. There’s a Prothonotary Warbler within the web! George and McClain have began eradicating the chicken, however we haven’t heard any shouts of pleasure. The volunteers collect subsequent to the web to anxiously watch. McClain confirms that the chicken is The Dude, however McClain doesn’t look glad. Lastly, he offers us the unhealthy information: The geolocator is gone.
Tanner’s smile melts and her eyes go broad. She stands frozen along with her mouth agape for a number of seconds, after which she offers a resigned smile. What else can she do? McClain carries The Dude again to the banding station, him with profound disappointment, as if he’s been tricked. Realizing full properly that it will likely be even more durable to seize him a fourth time, the group collectively decides to place one other geolocator on The Dude. They take his measurements and ship him again to his chicks.
Tanner has had a few years to brace herself for disappointments like this. “Making an attempt to catch this chicken will not be for the faint of coronary heart, as a result of you’re going to fail greater than you’re going to succeed,” she tells me. She is aware of how unlikely it’s for a 14-gram chicken to fly to Colombia and again. Doing this work requires an amazing quantity of hope, she says, and recapturing Hydrogen’s geolocator is greater than she may have hoped for.
“It’s a miracle,” she says, “And I can’t wait to see what his knowledge present.”
With that sense of surprise, this crew of chicken lovers has come to date, and their work is simply simply starting. All through the summer season of 2026, George and McClain deployed 36 geolocators on Prothonotary Warblers in jap Kansas. There could also be many extra miracles to come back.
