The epic total solar eclipse of 2024 caused some birds to stop singing

During the 2024 total solar eclipse that captured the attention of space lovers across North America, something was going on with the birds.

Scientists documented an unexpected shift in birds' vocal behaviors during the eclipse using data from 344 community-based monitoring devices known as Haikuboxes. Researchers from Loggerhead Instruments, Inc. and the Cornell Lab of Ornithology's K. Lisa Yang Center for Conservation Bioacoustics managed to use these boxes to glean clear evidence that birds responded audibly to the celestial event.

"Anecdotal evidence has long suggested that birds fall silent or exhibit nighttime behaviors during a total solar eclipse," David Mann, lead author of the study and researcher at Loggerhead Instruments, said in a statement. "Our study shows that on average, birds do get quiet during and just after totality, but we also learned that this behavior is strongly linked to the degree of darkness experienced."

The study draws on contributions from citizen scientists who host acoustic monitoring devices at sites across the United States. These devices enable researchers to study wildlife behavior over broad geographic areas with the help of artificial intelligence — and without the biases that come with direct human observation.

"Our first, quick look at Haikubox data just a few hours after the eclipse showed a large dip in bird vocalizations around the time of peak totality," Mann continued. "When we dove deeper into the data and removed any sites where humans may have influenced the birds' behaviors, we found a much more complicated story."

Mann says the team observed a range of bird responses depending on species and location. For instance, Black-capped Chickadees were silent until well after totality at a site in New York, but increased vocalizations during and just after totality at a site in Vermont. American Robins continued singing through totality in Kentucky, while Pine Siskins fell completely silent during the eclipse in Maine.

"The variability in bird responses and site differences was fascinating," he said. "We really don’t know why birds had such different responses to the total darkness during the eclipse. Despite examining factors like temperature, cloud cover, and wind speed, we found no significant relationship with changes in vocalization rates. This strongly suggests that the sudden total darkness and associated changes in wind and temperature were the primary drivers of the observed behavioral shifts."

This work highlights the important role that community science plays, and the potential to study animals with minimal disruption to their natural behavior. By using technology like Haikuboxes, scientists can gather large amounts of data, gathering insights that would be difficult or impossible to obtain through traditional methods.

"Our findings can inform future research on the impacts of light pollution and sudden changes in light levels on bird behavior," stated Mann. "Furthermore, it proves that when we combine the power of community science with clever technology, we can learn amazing things about wildlife without disturbing them, which may inform future continental-scale studies."