Saw-whet Owls on the move
We were thrilled to continue our collaboration with the Northern Saw-whet Owl Migratory Connectivity study this summer. As part of University of Delaware graduate student Aaron Coolman’s project, we deployed 15 Northern Saw-whet Owls (NSWO) with tiny radio transmitters, called nanotags, this summer. We first met Aaron when he came to Whitefish Point a few years ago to volunteer with our NSWO nest box study. We were naturally interested when he told us about his graduate project and excited to become collaborators with this Project Owlnet sponsored study last summer. We have now tagged 37 of our summer saw-whets at Whitefish Point with nanotags-22 adults and 15 juveniles.
For those of you not familiar, here is a brief overview of how nanotags work. Nanotags are small transmitters that can be put on animals as small as dragonflies. They work in conjunction with the Motus tower network. These small transmitters emit a signal that can be detected and identified by Motus towers if the animal carrying them passes within a tower’s range. There is a network of Motus towers across North America, but there are naturally still gaps in the coverage that these towers provide. We will be providing more of the results from this collaboration in the future, but wanted to share some recent detections from four of our tagged Friends of Whitefish Point owls with you. The below maps show gray dots that represent Motus tower locations and highlight the towers that these individual owls have been detected by.
The above map is from a saw-whet we tagged on July 1, 2025. It is a male that hatched in 2024. His track suggests that he passed through Michigan’s Garden Peninsula and then island-hopped his way to the Door Peninsula in Wisconsin. He was detected by a tower on Washington Island, located between the two peninsulas at around 9:30 PM on October 4. Approximately four hours later he was detected by a tower about 43 miles further south on the Door Peninsula.
The above map is from a juvenile male saw-whet that we banded last summer on July 1, 2024. We did not hear back from this little guy until he was detected 15 months later near the Fathom Five National Marine Park on the Bruce Peninsula in Ontario on October 8, 2025 at around 11:20 PM. He was then picked up by a tower about 37 miles south around 7:30 PM the following night.
The above map is of a female we released on July 5, 2025. She hatched in 2024, so this was her second fall migration. She arrived in the Finger Lakes region of NY near Seneca Falls on October 21. She was next detected in the mountains of Pennsylvania near the town Jim Thorpe on November 11. Just about an hour later she was detected again about 37 miles away in Bucks County, PA. These detection locations from PA really got me excited. Growing up in eastern PA I found my first saw-whet nest about 25 miles from where this owl was detected near Jim Thorpe, and found my lifer saw-whet about 8 miles from where she was last detected.
This above map is from a juvenile female saw-whet we released on August 3, 2025 during her first migration. She was first detected on the border of WI and IL on October 11. She was then detected along the IL and IN border on October 20. Around four hours later she was detected around 85 miles to the southeast in Indiana. She continued moving southeast and was in southeast Kentucky on October 24. Her last detection was on November 3 from the mountains of western North Carolina!
It is very rewarding to be collaborating on this project with other organizations like Tadoussac Bird Observatory and Hilliardton Marsh. Hopefully we’ll hear more from these owls and some of our others as the continue moving and more towers upload their data.
Chris Neri