Intriguing Itinerary
Jun 4, 2025 11:18 AM
Technology helps scientists map bird’s migration route
John Kuntz, FWP Motus tech, sent out this email to fellow nongame program staff on a recent Monday morning:
“Hope you're all having a good start to your week. I was doing my Monday morning network check when I stumbled upon an interesting detection made last week. Our Liscomb Butte station located on the Custer National Forest northwest of Broadus picked up a Lesser Yellowlegs last Thursday. This bird was tagged two months ago on the 15th of March in…southern CHILE. That’s 97 degrees of latitude! IN TWO MONTHS!!!”
Big deal, you might think, it’s a bird on a migration route. Nothing new.
But what makes this exciting enough to use ALL CAPs to share the news is that it involved fairly new technology to establish a bird’s flight itinerary.
The Motus Wildlife Tracking System is an international, collaborative network of researchers that uses automated radio telemetry to simultaneously track hundreds of individuals of numerous species of birds, bats and insects.
These critters carry miniaturized radio transmitters that weigh as little as 0.15 grams. When the animal flies by any station set up across the globe, the transmitter's ping is logged – PONG! Now researchers know the location and can map the migration route and even calculate flight speed between stations. One such station is FWP’s Liscomb Butte station, as mentioned in Kuntz’s email.
Kuntz said lesser yellowlegs aren’t exactly a lesser-known species in Montana.
“They only stick around long enough to do a pit stop on their way through, so there are windows in the spring and fall to catch sight of one,” he said.
The itinerary of this lesser yellowlegs, according to Motus:
- Departure: Lepihue, Chile, April 10
- Route: Detections over western Guatemala on May 6 and the Liscomb Butte station on May 12
- Arrival: British Columbia May 17, a straight-line distance of 6,349 miles
- Average speed: 30 miles per hour
“Considering how fast we know some migrating birds can fly, one might argue that this one was taking it’s time at some points in the journey,” Kuntz said. “Maybe it stopped to see the largest porch swing in the world in Hebron, Nebraska? Unfortunately, Motus cannot answer such mysteries.”
What Motus can provide is a more precise map of a migrating bird's route, giving researchers everywhere a clearer picture of what stopover habitats this species and many others are looking for on their crazy, globe-spanning, twice-annual journeys.
“It's like seeing the auroras, a glimpse of a grizzly bear or Old Faithful,” Kuntz said. “We know about it, but when you actually see it, it’s exciting and humbling. It puts into perspective how massive and amazing the natural world is.”