Animals feel stressed during a solar eclipse.But not for the reason you think

Ahead of this month’s solar eclipse, biologist Adam Hartstone-Ross had a big question on his mind: Why are animals so stressed during totality?

On April 8, he and a team of researchers, zookeepers and high school students observed nearly three dozen different species at the Fort Worth Zoo in Texas when the moon passed through the afternoon sun, plunging the area into sudden darkness. species. Hatterstone-Ross said the animals were much less stressed than those he observed during the eclipse seven years ago, and thanks to “groundbreaking” preliminary data, he has an explanation.

‘Quite dramatic behaviour’

In 2017, Hartstone-Ross, a biology professor at North Carolina State University, organized a study of animal behavior during a total solar eclipse at the Riverbank Zoo and Gardens in Columbia, South Carolina. He said he wasn’t enthusiastic about solar eclipses until he discovered how little researchers knew about animal behavior during them. Scientists have not attempted a study of this scale since 1932.

Hatterstone-Ross said his team observed “pretty dramatic behavior” during the 2017 total eclipse. Galapagos tortoises begin mating. Gibbons let out an unusual cry. What interested him most was not the oddities themselves, but the reasons why they occurred.

“A large number of animals actually reacted as if they were becoming very depressed and stressed. We’re not sure why they were doing this,” he said.

That observation guided this month’s research, which involved a range of species including bonobos, owls, coyotes and crocodiles. Hartstone-Rose said the data revealed a nearly universal response across species, which the team noticed in 2017 but was confirmed earlier this month: At the moment of totality, when the sky darkens At this time, the animals begin their routine nocturnal activities: if night falls officially. For nocturnal animals, this means increased activity. For diurnal animals, this means taking a nap, returning indoors, or waiting for dinner.

Hatterstone-Ross said the most extreme reaction his team witnessed earlier this month came from Aldabra giant tortoises.

“These giant tortoises, each weighing over 100 pounds, wanted to get into the barn at night so badly that they stood up on their hind legs, which I didn’t even know tortoises could do, and they pushed the door so hard that they The door frame is actually bent,” he said.

Canadian astronomer Pierre Chastenay, who helped lead separate studies of 12 species at Quebec City’s Granby Zoo, agreed with the findings. He was tasked with observing Japanese macaques and recalled that at the moment of full food, they lowered their heads in preparation for sleep. After a few minutes, they became active again, foraging for food, grooming, and chatting.

“They were talking to each other in macaque language, probably saying, ‘What the hell happened? This is the shortest night I’ve ever had,'” Chastnay said.

Consider human factors

Hartstone-Ross said that when animals’ evening routines are disrupted, they experience lower levels of stress, “like turning the stress knob to one or two.” April 8, Hartstone -Rose and Chastenay respectively observed that the species never became as stressed or unstable as in 2017, exceeding such low levels. Contacted and heard they were doing similar research. As for why pressure remains so low, they have a hypothesis: fewer people are screaming.

“This seems to be strong evidence that animals that show anxiety during a solar eclipse are anxious not because of the eclipse itself, but because of the human response to the eclipse,” Hatterstone-Ross said. “We think that Animals are much more sensitive to our own emotions during a solar eclipse than we previously thought.”

Hatterstone-Ross recalled the fireworks, cheers and chaos when he was stationed along the path of totality in 2017. They’re limiting the event to about 2,200 people, a modest number compared to the typical weekend crowd of 8,000.

At Granby Zoo, the cheers from visitors were completely absent. The zoo was closed to the public that day, which is typical on weekdays during the off-season. During periods of full food, the animals engage in normal, instinctive nocturnal behaviors with little disruption, Chastenay said. Nocturnal animals are active and diurnal animals are calm.

“I think our study will be a landmark, so to speak, because from now on, if people want to do this kind of research in zoos during a total solar eclipse, they’re going to have to think about whether humans are crazy during a total solar eclipse,” Chas said. Tenay said.

Hatterstone-Ross said that despite his findings, he does not believe zoos will need to limit or eliminate visitors during future eclipses. Instead, he said, the zoo is “a magical place” during such events, and the cost to animals of temporary stress is low.

“Animals in zoos actually behave very well compared to animals in the wild,” he said. “We should be aware of efforts to reduce stress in zoo animals, especially when they are habitually stressed. But allowing animals to be stressed occasionally is actually a very natural state for them.”

Both scientists are looking ahead to future solar eclipse events. Hartstone-Ross hopes to translate the research tools into other languages ​​to determine whether researchers on other continents observe similar animal behavior. He also plans to survey animals in the wild, including during the 2030 total solar eclipse across southern Africa.

“I think this is the beginning of a very fruitful collaboration,” Chastenay said of his work with Halstone-Ross.