Sounding out animal reactions to the 2024 eclipse

No natural phenomenon provides a rarer chance to study the secrets of the animal world than a total solar eclipse.

This was recently demonstrated by researchers investigating how a total solar eclipse might affect the soundscape of Midwestern United States prairie communities . Their objective was to discover how soundscapes - combinations of natural and artificial sounds that shape an environment - are influenced by ambient light, as light level helps cue annual biological events such as sexual reproduction and migration.

Using novel acoustic capture devices to record animal vocalizations in the days before, during and after the April 2024 eclipse, researchers measured changes in soundscape diversity, complexity, and intensity at three different sites in Ohio: Larry R. Yoder Prairie Learning Laboratory , the Tecumseh Nature Preserve and Highbanks Metro Park . Their findings showed that while the eclipse was associated with both changes in sound activity and diversity, it was not associated with major changes in acoustic complexity.

"Solar eclipses are wonderful events that let us experiment in natural settings what sudden losses of light could be doing to animals," said Madison Von Deylen, lead author of the study and a PhD student in evolution, ecology and organismal biology at The Ohio State University .

"Both overexposure and underexposure to light can have negative consequences on animal physiology, and only a handful of studies have experimentally assessed how eclipses influence animal behavior."

The study was recently published in the journal Ethology Ecology & Evolution .

While similar soundscape research has been used to detect cryptic species and even identify members of those once thought extinct, Von Deylen said this study is one of the few to have used passive acoustic monitoring to quantify the effects of a solar eclipse on the animal soundscape.

"We used a fairly novel technique to accomplish this," she said. "Acoustic monitoring and soundscape analysis has a lot of promise for being able to track changes in ecosystem composition over time."

Analyzing these subtle ecosystem changes allowed the team to dig deeper into the circumstances behind their results. For example, the time of year was important in this work. Any number of environmental differences would have altered the natural soundscape, but since the eclipse coincided with the breeding season for many prairie birds, many unique calling patterns were able to be detected.

Initially, researchers expected that a sudden decrease in ambient light would cause the prairie soundscape to mimic that of dusk. Their results suggest that overall sound activity was highest on the day of the eclipse, suggesting that even temporary environmental changes, such as lowered temperatures and moon phases, can inspire unexpected behavioral responses.

These new insights will not only aid scientists in understanding animal adaptability in the wild, but could spark new ideas on how to quantitatively measure environmental change, said Von Deylen,

"The conclusions that we were able to draw from this study were extremely context-specific," said Von Deylen. "But it lays the groundwork for more complex, larger-scale studies."

Future work will likely aim to sharpen the novel quantitative methods used in this paper so that soundscape analysis can become a vital research tool for other areas of study as well.

"I'm really excited to see where soundscape work goes in the next couple of decades," said Von Deylen. ""It will be of great help in answering new conservation questions."

The study was supported by Ohio State's Summer Research Opportunities Program. Other Ohio State co-authors include Sabeel Haddad and Susan Gershman.