During the upcoming solar eclipse on Monday, Aug. 21, many will presumably look up at the sky, observing the few spectacular moments of darkness.

But how will our furry friends respond to the sudden shift?

While there hasn’t been much research done on the behavior of animals during an eclipse, reports of strange activity have piled up during the events.

Joanna Chiu, a professor of entomology at UC Davis, has an explanation for this behavior.

Chiu is an expert on circadian clocks, the internal biological timer that governs daily rhythms of physiology and behavior in organisms.

While Chiu explains that circadian clocks can keep running even in constant darkness, this does not mean that animal behavior won’t be affected.

“There are many examples in the animal world where all kinds of animals are affected by eclipse,” Chiu said.

Chiu explained a phenomenon known as the “masking effect,” where “certain environmental stimuli can overrule normal organismal behavior temporarily without affecting the internal clock.”

Kristina Horback, a professor of ethology [the behavior of animals] at UC Davis, explained the kind of animal behaviors one might expect to see during the eclipse — but noted that much of it comes from anecdotal evidence.

“Generally, some animals will display behaviors that would naturally occur at dusk. If the animals are diurnal they may start to reduce sound or movement, and get ready for bed,” Horback said. “If animals are most active at dawn and dusk, they may display common behaviors performed at dusk, like an increase in sound production like chirping or singing.

“It is possible that some prey animals could interpret a shadow over the sun as an aerial predator, and thus may show avoidance behavior."

In an effort to gather more scientific evidence, the California Academy of Sciences has launched the Life Responds project on the iNaturalist app, where users will be able to record observations.

So if you’re lucky enough to be in the path of totality — the area which will experience complete darkness — be sure to listen for the birds chirping, or the eerie lack thereof.

Verify sources:
Joanna Chiu, Vice Chair of the Department of Entomology and Nematology at UC Davis
Kristina Horback, a professor of ethology at UC Davis

Verify resources:
Life Responds project on the iNaturalist app
Reports of animal behavior during an eclipse