The 2017 solar eclipse is fast approaching, and all over the US people are getting their glasses and travel plans in order for the occasion.
But animals don’t follow the news. On August 21, they’ll be completely surprised by the darkness caused by the moon blotting out the sun for about three minutes along the path of totality. How will they respond?
David Baron, a journalist and author of the 2017 book American Eclipse, gathered accounts from a 1878 eclipse that was visible from Montana to Texas (a more northern to southern path than th upcoming eclipse). According to reports from the time, animals went buck-wild:
Animals perceived the ebbing of the light, and they responded as they normally would at the close of day. In Rawlins, [Wyoming] owls emerged. Farther north, in a Montana gold mining down, “all the cocks in the city began to crow lustily and in a regular succession.” Across the region, cows turned homeward and pigeons went to roost. Grasshoppers folded their wings and fell to the ground.
Some of this may be true, although because eclipses don’t happen every day, it’s hard to collect enough information to say for sure. Anecdotal evidence isn’t great because it’s not easily replicable, but it’s better than nothing. With that in mind, researchers are still making their best guesses based on a handful of observational studied and knowledge of general animal behavior.
Birds will almost definitely get their feathers in a flutter as a result of the darkness. “Birds are very visual and affected in major ways by light,” Marilyn Ramenofsky, an ornithologist at the University of California-Davis, said in an email. “During daylight hours birds rely heavily on visual cues. So with a sudden drop in brightness, their reaction is to seek out shelter, protection, roost sites, etc.” Although she wasn’t sure what nocturnal birds, would do specifically, she did say that they are used to more gradual changes in darkness, so the quickly-moving eclipse may throw them off and cause them to awake from their daytime sleep.
Some insects have also been seen to behave strangely in eclipse darkness. The orb spider, which lives in the US, was observed taking down its own web during a 1991 eclipse, only to re-spin it afterward. Although there’s no scientific documentation of grasshoppers actually falling from the air, scientists studying a 1999 eclipse heard them stop singing (paywall) during the minutes in which the moon blocked the sun’s light.
Twelve cows observed in Europe during a 1999 eclipse didn’t (paywall) do much of anything. Admittedly, this is a very small sample size, though other accounts (audio, listen at 9:50) suggest that cows do return to their barns during solar eclipses because they assume it’s nighttime. Other accounts of animals living in close proximity to humans from a 1932 eclipse in the Northeast US describe dogs running and hiding during the event, as Buzzfeed reports. Cats, on the other hand, are typically as ambivalent to a solar eclipse as they are to life, Bill Kramer, a 16-time eclipse viewer, told Vox.
Other animals that aren’t found roaming across the US have been observed behaving abnormally during solar eclipses in other parts of the world. Doug Duncan an astronomer at the University of Colorado-Boulder, one time saw a flood of llamas emerge during an eclipse in Bolivia, who then all disappeared afterward. He also observed marine mammals jump at the front of his boat for the duration of another (presumably in 1998; Duncan never gives the year) before returning to the depths of the water. Tropical bats, owl monkeys, red-faced lemurs, and chimpanzees have all been found to either take to the skies more than usual (in the bats’ case), or stop what they were doing to watch the totality.
Though these animals are not native to the continental US, they may live in zoos or animal sanctuaries across the country, where you may be able to watch them watch the sun. If you do, animal behavior scientists would love to know what you saw. The iNaturalist app, created by scientists at the California Academy of Sciences, allows you to take a picture of animals you see and crowdsource its identity with the help of actual biologists. On Aug. 21, users will be able to join a group called Life Responds where you can record any animal behavior during the 2017 eclipse so scientists can study them later.
The majority of animals, though, probably won’t be the affected by the event. “[Animals] may begin to respond to the false dusk, but their intrinsic biological clocks will still tell them it’s still afternoon,” Bryant Buchanan, a biologist studying nocturnal animals at the Utica College in New York, said in an email. “Then, of course, as light levels increase any dusk activated genetic activity will move into daylight genetic activity.” In other words, animals won’t have time within the period of the eclipse to fully respond to the fact that their day is, for a moment, night. “It’s hard to imagine that the eclipse would have much more of an effect than temporary confusion.”