Solar Eclipse has this strange impact on birds: Researchers reveal surprising details

Nature is a cradle of unexpected surprises that often go beyond the explanation of science, a leading example of which could be the eerie silence that accompanies the darkness that comes with a total solar eclipse. Birds, which are typically loud and active during the day, stop chirping as the sky gets covered by darkness.
This interesting behaviour of avian creatures has surprised observers for years, and many relate this to the sudden change to something unexpected. However, scientists had taken a closer look at this behaviour during the 2024 total solar eclipse and noted down the observations through a systematic scheme.

A study published in Scientific Reports explains how birds responded to the eclipse on April 8, 2024, and found out some gripping information about their behaviour. The research, which used a new approach to gather data, confirmed that birds actually quiet down as the ‘totality’ of the eclipse approaches. However, the birds don’t go entirely silent until the sun is obscured by about 99 percent.
One of the key observations in this study was the use of remote acoustic monitoring that was different from the previous efforts, where human presence might have impacted bird behaviour, researchers placed 344 acoustic monitoring devices known as "Haikuboxes" in various locations.
This helped in unbiased and continuous data collection, without human interference. David Mann, a researcher at Loggerhead Instruments and one of the study's authors, explained, “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.”

Researchers removed human voices from the data

The researchers went a step ahead, removing any data from sites where humans were also heard because excitement and celebrations could have altered the birds' responses. Once the human factor was eliminated, the data revealed that birds became completely silent only during totality, the brief period when the sun was fully obscured. This was an important observation that had not been fully understood in past studies.
Another surprising information from the study was the difference in responses from varied bird species and even the same species at different locations. For example, black-capped chickadees in New York State remained quiet long after the totality had passed. Meanwhile, their species of birds in Vermont began singing again during and immediately after the eclipse’s peak. "The variability in bird responses and site differences was fascinating," said Mann. "We really don’t know why birds had such different responses to the total darkness during the eclipse."

What are the reasons why the birds go silent?

What was interesting about the research was that factors such as temperature, wind, and cloud cover, alone did not appear to influence the birds’ sounds. This led the researchers to conclude that the sudden coverage of the sky with darkness, along with the changes in wind and temperature, were mostly the main triggers behind the birds’ change in behaviour.