by Pepper Trail, PLAYA Science Council
In February 2025, PLAYA joined a worldwide wildlife tracking program called Motus, coordinated by Birds Canada. PLAYA facilities manager Simon Lagneaux and Motus Pacific Northwest Coordinator William Blake installed a tracking station up on the PLAYA “bench,” with a sweeping view over the Summer Lake basin. The antenna is constantly “listening” for the signals of tagged birds or bats (or even monarch butterflies!) passing within a 9-mile detection radius. Data on the detected species’ identity – encoded in the signal – along with the date and time of the detection, are recorded in the station and transmitted to the Motus database, allowing the migratory movements of tagged animals to be tracked without the need for recapture or even direct observation.
As of March 2026, our Motus station has detected six individual birds of three species: Lewis’s Woodpecker, Dunlin sandpiper, and Wilson’s Phalarope. This report describes the journeys of one of those birds, Wilson’s Phalarope #48618, showing the amazing power of the Motus network, and PLAYA’s contribution to our knowledge of this fascinating little shorebird.
Wilson’s Phalaropes have several claims to fame. One is the species’ highly unusual polyandrous mating system. In a reversal of the common arrangement, female phalaropes are larger and more colorful than males, and often mate with, and lay clutches of eggs for, multiple males, who then carry out incubation and parental duties. But of more relevance to PLAYA, Wilson’s Phalaropes are also famous for being dependent on saline lakes, including Lake Abert.
The species breeds in both fresh and saline wetlands of interior western North America, including the Summer Lake Wildlife Area and in the Chewaucan wetlands. But for the remainder of the annual cycle, it is a salt-lake specialist. When conditions are good in Lake Abert, tens of thousands of Wilson’s Phalaropes gather there in the late summer to feast on brine shrimp and brine flies, laying down fat to fuel their long migration to saline lakes in South America, with most spending the winter in the Patagonia region of Argentina and Chile.
To understand this amazing bird and its unique ecology, the International Phalarope Working Group has established a project, “Phalarope Movement Across the Americas,” leading to Motus stations at Laguna Mar Chiquita in Argentina and elsewhere along the migratory route (for more, see International Phalarope Working Group and Motus).
So, what do we know about #48618, and how did PLAYA’s Motus station help us tell this story?
The phalarope was captured and given a Motus tag in the Klamath Basin in August 2024. The tagging was part of a collaborative effort between the USGS Western Ecological Research Center, Oikonos Ecosystem Knowledge, and Dr. Margaret Rubega. After tagging, it moved south to Ash Creek, southwest of Alturas. It then worked its way south through California, with detections near Bakersfield and Barstow, after which it crossed into Arizona near Quartzite on September 11. After that, it disappeared from the Motus network until October 30, when its signal was picked up on the coast of Ecuador, a straight-line distance of over 3300 miles!
Of course, it is very unlikely that our bird flew directly from Arizona to Ecuador. There are relatively few Motus stations in Central and South America, so detections in that region are low. Phalarope 48618 probably made a number of stops at saline lakes in Mexico and further south in Central America and coastal South America. And Ecuador was just another layover. From there, our bird continued on to the saline Laguna Mar Chiquita in Cordova Province of Argentina, across the Andes and over 2300 miles from the coast of Ecuador. There it was detected on March 6, 2025.
Laguna Mar Chiquita is a huge saline lake – the largest lake by surface area in South America – full of the brine shrimp that the birds depend on. Part of Argentina’s new Ansenuza National Park, it is famous for its flamingos, and is also a well-known wintering destination for Wilson’s Phalaropes. 48618 probably arrived there months before its detection in early March.
Sometime in early spring, 48618 felt the stirring of the migratory urge once again, and knew it was time to return north. We don’t know the route it took, but we do know that on May14, it was again detected by the Motus network, near Brownsville, Texas.
After refueling for a few days, it set off again on May 22, flying northwest along the Rio Grande. In the next four hours, it travelled over 100 miles (as the phalarope flies) to near the town of Roma, where it turned sharply north. Making a marathon flight, it was next detected at the Matador Wildlife Management Area near Paducah, Texas: a straight-line distance of over 500 miles at an average speed of 45 miles per hour! Even then, 48618 didn’t stop. It flew right past the Matador antenna and continued for another 200 miles, reaching a station on the Texas-Oklahoma border on May 23. After a short half-hour stop, it was off again, and by May 24 had reached northern Colorado, a flight of over 300 miles at the amazing average speed of 67 miles per hour! Such a speed was likely assisted by tail winds; migratory birds are experts at detecting and taking advantage of weather conditions.
After another very short (12 minute) stop, 48618 flew onward. It was detected by two Motus stations in Idaho on May 24 and 25, leaving the vicinity of Salmon, Idaho on May 25. After that, its signal was not picked up again. We can only speculate that it continued north to nest in the wetlands of eastern British Columbia or Alberta.
But that’s not the end of the story – and the time has come when PLAYA makes its contribution! By July 2025, 48618 was once again in migratory mode, now headed back south. It was first detected by the Motus antenna at the Summer Lake Wildlife Area on July 27. It flew right by the wildlife area, but stopped at PLAYA for seven hours before continuing south. It then spent almost a month in the vicinity of Eagle Lake, where it likely lay down a good layer of fat before taking off on August 20 on a high-speed flight south. That took it past Motus stations near Honey Lake, Reno, Las Vegas, and Prescott, Arizona. On August 22, 2025, it passed a station on the Arizona-Mexico border and then…
Well, we don’t know. 48618 has not been detected by a Motus station since August 22, 2025. We can hope that it continued south and has spent a pleasant winter in Argentina, and then headed north again. If so, and if it passes another Motus station anywhere, its location will show up in PLAYA’s records, because this amazing little sandpiper is now a PLAYA bird, and we are part of its story.
And the story of PLAYA and Wilson’s Phalaropes doesn’t end with 48618. Ron Larson, a member of PLAYA’s Science Council, literally wrote the book on the natural history of Lake Abert, which is so important as a migratory stopover site for this species. He has long been involved with phalarope surveys on the lake. Another PLAYA Science Council member, Karen Shimamoto, has close ties with the Lakeview community, and also with Rotary International, which is one of the supporters of Experiencia Ambientalia, a youth environmental group in Argentina that is helping to study and protect phalaropes at Laguna Mar Chiquita.
Experiencia Ambientalia is part of a developing network monitoring phalaropes at North and South American saline lakes, including Laguna Mar Chiquita, Mono Lake, and the Great Salt Lake. PLAYA is supporting efforts to incorporate Lake Abert into this network. Karen and Ron are working with Lakeview High School teacher James Johnson to teach Lake County students about Lake Abert and its importance, and to connect them with the students in Argentina.
With spring migration getting under, we look forward to more detections by the PLAYA Motus station. It will be exciting to see what passes by, and what stories these incredible travelers have to share.
To learn more about Wilson’s Phalaropes and the importance of saline lakes, see:
– Audubon Article: Saline Lakes Are Dying—Scientists Hope This Unusual Shorebird Can Help Save Them
– Oikonos Article: A new national park at Laguna Mar Chiquita, Argentina, brings communities together from across the hemisphere to celebrate phalaropes and saline lakes