In the aftermath of the 2017 American solar eclipse, there were lots of reports of animals acting strangely. Now a new analysis of Doppler radar data from during the event seems to prove that there was something to those reports, at least as it pertains to birds and insects, reports Phys.org.
The analysis draws data from 143 weather stations that had captured the activities of flocks of birds and swarms of insects in different parts of the United States during the eclipse. Although Doppler is most often used in meteorology to track the weather, it can also pick up the movements of groups of flying animals as well. This gave an unprecedented look at how these animals might react to an unusual astronomical event.
Researchers were able to narrow down the movements of flying species from the Doppler data using machine-learning programs that captured the animals from near the ground to as high as three miles. According to the report, unusual activity can be seen up to 50 minutes before the eclipse reached totality, with birds moving en masse to return to the ground or to secure perches. This is the kind of behavior expected from birds prior to a storm, to seek shelter.
As the eclipse reached totality, however, the birds' behavior suddenly changed. They began a frantic cycle of taking flight again, then returning to their perches, then taking flight again, and so on. Researchers' best guess is that the birds became "confused," as if they weren't sure what was happening. Was there a storm coming? Was it just getting dark out?
The report is also keen to point out that in the lifespan of most species of bird or insect, they are unlikely to have ever experienced an eclipse before. The event represents a truly novel and unexpected change to their environment, so it's understandable that it might cause some confusion.
The team working on the study, which is composed of researchers from Cornell University and the University of Oxford, now have their sights set on 2024, when another solar eclipse is scheduled to pass over the continental United States. They hope that their dataset can be refined, to develop a better idea of exactly what is going on with flying animals during these unusual events.