While millions of people prepare to watch the total solar eclipse that will cross North America on Monday, animals in the affected area – in homes, on farms, in zoos and in the wild – missed the news that the moon will it blocks the sun, briefly turning day into night.
How they react to this rapid and unexpected change in light and temperature, which in some places will last up to four and a half minutes, is anyone’s guess.
Cows can go into their stalls to sleep. Flamingos may huddle together out of fear. The giant, slow-moving Galapagos tortoise can even become frisky and mate.
Circadian rhythms can take a noticeable hit, with nocturnal animals accidentally waking up and starting their day only to realize that, oops, the night is already over. And then there will be some animals, perhaps particularly lazy domestic cats or foraging pigs, who may not give the dark sky a second thought.
“Everybody wants to see how they’re going to react,” said Robert Shumaker, CEO and president of the Indianapolis Zoo, which will experience nearly four minutes of darkness. It is one of several prominent zoos located along the path of totality, a gentle arc stretching from Texas to Maine, where researchers, animal keepers, volunteers and the public will study the animals’ response to the eclipse.
Dr. Shumaker, an expert on animal behavior and cognition, said that “most animals, of course, will notice that something unusual is happening.”
Most animals will likely be confused by the darkness and begin their nightly routines, said Dr. M. Leanne Lilly, a veterinary behaviorist at Ohio State’s College of Veterinary Medicine.
But the way people react to the eclipse — by looking at the sky, expressing excitement or gathering in a group — could affect domesticated animals, such as dogs or cats, because pets can act strangely when people act strangely, Dr. Lily said.
“This can make any of our domestic animals feel that things are not as safe and predictable as they are supposed to be,” Dr Lilly said, adding that any unusual human behavior can disturb pets because they are “domesticated to to take care of us. “
“We might be the problem,” he said with a laugh.
How animals will react to solar eclipses can only provide clues to animal behavior because the relatively few studies on the subject are often conflicting. A study in 1560 reported that “the birds fell to the ground.” Other studies said the birds went to rest, or fell silent, or continued to sing and chirp – or flew straight home. The dogs either barked or whined, or they didn’t bark or whine.
A study of the 1932 eclipse, believed to be the first comprehensive investigation of the subject to include observations from the public, explained that it received “much conflicting testimony” from people who had seen mammals. He concluded that several animals showed the strongest reactions: squirrels ran into the woods and cattle and sheep headed for their barns.
The zoo animals, the study said, showed little or no response, and Dr. Shumaker doesn’t expect the Indianapolis Zoo animals to show a very unusual response because they “take a lot of things in stride.”
“We think this will be a very simple and easy experience for the animals,” he said, adding that some may experience “a little confusion” about what’s going on. “I certainly don’t expect it to be a concern for them.”
Dr. Shumaker is as curious as anyone to see what the animals will do, and in 2017, Adam Hartstone-Rose, now a professor of biological sciences at North Carolina State University, tried to get some answers. Before this total solar eclipse crossed the United States, a formal animal study began at the Riverbanks Zoo & Garden in Columbia, SC, and resulted in what was possibly the largest study of animals during an eclipse since the 1932 attempt.
Just as he does next week at the Fort Worth Zoo, Dr. Hartston-Rose assembled a team of researchers, animal breeders and volunteers to observe the animals before, during and after the set.
About three-quarters of the 17 species his team studied, including mammals, birds and reptiles, exhibited behavioral cues to the eclipse, with many of these animals believing the change in light meant it was time to prepare for bed. A smaller group of animals, including giraffes, baboons, gorillas, flamingos, lorikeets (a type of parrot) and a Komodo dragon exhibited behavior that was unusual and could be interpreted as anxiety.
According to the study, the baboons ran around their enclosure as totality approached, and one walked in circles for about 25 minutes. A male gorilla filled the glass. The flamingos huddled together, surrounding their young, calling loudly and looking skyward, which they may do if they think there’s an aerial predator around,” Dr Hartston-Rose said.
The lorikeets became active and loud just before totality, and during totality they flew together on one side of their display. A Komodo dragon rushed into his lair, but the door was closed and he “ran erratically” until daylight returned.
He noted that it was “entirely possible” the behaviors were triggered not by the eclipse, but by the large crowds and noises at the zoo, which included fireworks exploding in the distance.
However, the behavior of the giraffes that day in South Carolina was similar to the animals’ behavior in other places during eclipses, including at the Nashville Zoo in 2017, as well as in the wild in Zambia during an eclipse. in 2001.
“Most of us expected the giraffes to be like, ‘Oh, it’s dark, so it’s time to sleep,'” said Alyson Proveaux, curator of mammals at Riverbanks Zoo and one of the giraffe observers in 2017. Their reaction was much more dramatic.
Normally, the giraffes at Riverbanks Zoo are eating lettuce, chewing, toasting or playing with their enrichment toys. But when the sky darkened, according to the study, they stopped eating and huddled in the back of their enclosure, pacing and swaying. As daylight slowly returned, several broke into a gallop for several minutes, which was extremely inappropriate. Giraffes also galloped during the eclipse at the Nashville Zoo and in Zambia.
“They are creatures of habit,” Ms. Proveaux said. “So we just rocked their world.”
Elsewhere at Riverbanks Zoo, Galapagos tortoises did something even stranger just before totality that the study described as a “novel response.” Instead of moving slowly around their territory, as they usually do, they came together and two began to mate. Overall, all four turtles were moving faster than usual.
Dr. Hartston-Rose is curious to see if these responses will be replicated by animals at the Fort Worth Zoo, where he will likely be watching bonobos, which are similar to chimpanzees. He said bonobos often engage in sexual behavior to relieve stress, and it will be fascinating to see their response to the unexpected darkness.
He too asks the public to observe solemnly the animals around them during the eclipse and submit these findings to him for inclusion in his study. These animals include pets, animals, as well as wild animals, which are also known to change their behavior during eclipses.
Scientists have used different types of technology to record wildlife reactions to an eclipse. For the 2017 solar eclipse, scientists radar data were used from weather stations across the country to study how flying animals reacted when day turned to night.
As the sky darkened, the amount of biological activity in the atmosphere dropped, they found, suggesting that insects were landing and birds were beginning to roost. In some places, there were also brief pulses of activity during totality when some nocturnal creatures—which may have included bats, some insects, and night-migrating birds—came to life.
However, the brief period of darkness did not seem significant enough to completely convince the animals that night. “It’s kind of a muted response,” said Andrew Farnsworth, a visiting scientist at the Cornell Lab of Ornithology who authored the study.
Some animals, including many butterflies, are particularly sensitive to temperature. During the 2017 eclipse, Robert Michael Pyle, an ecologist and butterfly expert in southwest Washington, spent hours carefully recording the conditions in his yard and as the temperature dropped, the forest captains, a common species of butterfly, disappeared. “Two degrees puts the butterflies back to bed,” he said.
Although they have been the focus of less research, plants, which need the sun for sustenance, are also affected by eclipses. “As the sun goes away, photosynthesis drops,” said Daniel Beverly, an ecophysiologist at Indiana University who documented this slowdown in the great sage during the 2017 eclipse. The findings underscore the importance of circadian rhythms beyond the animal kingdom, he said.
And careful observations of what organisms do during an eclipse can yield new insights that extend beyond the event itself. The eclipse “is kind of a physical experiment, manipulating light and temperature on a large scale,” said Candace Galen, an evolutionary ecologist at the University of Missouri who found that the bees fell silent during the overall period of 2017.
In the end, Dr. Hartston-Rose said, “who knows what goes on in a giraffe’s head.” But his goal is to collect as much data as he can, to try to find out.
He has a clear answer to a question he gets asked time and time again: During an eclipse, should you put goggles on your dog?
“As a fashion statement, I’m all for it, so go for it,” she said. “But as a safety precaution, no, that’s not something they should do. Animals don’t look at the sun.”