A new paper by UCLA ecologists explores how the disturbances to Earth’s magnetic field can lead birds astray — a phenomenon scientists call “vagrancy” — even in perfect weather, and especially during fall migration.
“There’s increasing evidence that birds can actually see geomagnetic fields,” said Morgan Tingley, the paper's corresponding author and a UCLA associate professor of ecology and evolutionary biology. “In familiar areas, birds may navigate by geography, but in some situations it’s easier to use geomagnetism.”
Lead researcher Benjamin Tonelli, a UCLA doctoral student, worked with Tingley and postdoctoral researcher Casey Youngflesh to compare data from 2.2 million birds, representing 152 species, that had been captured and released between 1960 and 2019 — part of a United States Geological Survey tracking program — against historic records of geomagnetic disturbances and solar activity.
With North America’s bird populations steadily declining, assessing the causes of vagrancy could help scientists better understand the threats birds face and the ways they adapt to those threats.
To understand more about how magnetic fields affect bird migrations, go to UCLA Newsroom.
Image Source: Always a birder/Wikimedia Commons
