Will the 2024 solar eclipse affect animals? What experts say

On Aug. 21, 2017, a solar eclipse shrouded The Riverbanks Zoo and Garden in Columbia, South Carolina, in near-total darkness for 2½ minutes.

In the time leading up to the darkness, during it, and after, zoo personnel observed and documented the behavior of many of the animals to see if the meteorological event would spark any changes. Oh did it.

Three female gorillas approached the den enclosure entrance as if it was time to go in for the evening, while the one male gorilla became unusually aggressive. The seven giraffes all stopped eating to huddle at the back of their enclosure, swaying with anxiety. The four Galapagos tortoises displayed the most novel behavior — just prior to totality, a pair of tortoises began mating, during totality all four tortoises “became more active, moved faster than had been seen during baseline observations and dispersed in various directions to different sections of the enclosure. Following totality, all tortoises gazed up at the sky.”

Those findings are outlined in a March 31, 2020, article, “Total Eclipse of the Zoo: Animal Behavior during a Total Solar Eclipse,” published in Animals, a global, peer-reviewed open access journal devoted to zoology and veterinary sciences, published semimonthly online. The Riverbanks Zoo’s study documented that three-fourth of the animals at the zoo exhibited some behavioral responses to the 2017 eclipse with the predominate response being to mimic nighttime behaviors. The next most common response was anxiety, the article said.

“There are lots of reports of animal behavior following lunar cycles and an eclipse is part of that astronomical cycle and it’s also really rare. So does it fall into that category where it is so rare that animals don’t have a sensitivity to it? Or do they?” said Erica Cartmill, professor of anthropology, animal behavior and cognitive science at Indiana University in Bloomington, Indiana.

Cartmill has not directly studied animal behavior during an eclipse, but is eager to know more and is calling on the public, in what he calls “citizen science.” She wants people to observe their pets’ or other animals’ behavior before, during and after the April 8 eclipse this year. She’s set up a website, www.observinganimals.org, for people interested in participating and recording it.

“These events are so rare we want to capture as much information as we can,” Cartmill said.

‘A little slice of night’

The topic of animal behavior during an eclipse goes far back. During a total solar eclipse in New England in 1932, anecdotal reports claimed many domestic dogs fell silent during the eclipse, horses clustered together and began shaking their heads and tails with anxiety and several species of wild birds such as crows, gulls and sparrows stopped flying and remained silent and still, according to the article in Animals.

Cartmill has read those reports, but the only evidence of animal behavior during an eclipse that he has seen first-hand is an anecdote from the solar eclipse on Aug. 21, 2017. She was at Maryville College in Maryville, Tennessee, about 17 miles south of Knoxville, in a field to observe the event.

“We were near a little patch of woods and when it was like two minutes before totality and 97% of the light was blocked, it still looked like day, but it was a little bit colder,” Cartmill said. “As soon as it hit totality, we heard crickets chirping and bats flying out of the woods. It was like a little slice of night and we felt like we were trespassing. It was truly beautiful. One minute the birds were flying and singing, and the next minute crickets were chirping and bats were out.”

Historically most reports of animal behavior during an eclipse have been inconsistent and inconsistent, experts in various articles said and Cartmill agreed. For example, the anecdotal accounts of dogs growing quiet in 1932 contradicts social media reports in 2017 of dogs increasing vocalizations during the “Great American Eclipse of Aug. 21, 2017,” according to a Feb. 2019 article in Animals.

What to expect

Cartmill offered an explanation for the conflicting reports as part of “an information cascade.” That’s when early reports get confirmed and then amplified.

“So if four people said, ‘My dog did this thing,’ you might say, ‘I think my dog did that same thing,’ ” Cartmill said. “It doesn’t mean they’re lying, but we tend to remember things that align with what other people see.”

There are four things likely to happen to animal behavior during the eclipse, she said:

Animals won’t do anything unusual.
Animals will do evening behaviors. For example, if a dog is used for a bedtime treat, he may go to the kitchen to wait for it.
Animals will display signs of increased anxiety such as scratching, yawning, circling and pacing or if they are animals that typically flock together, they will start grouping.
Animals display unexpected behavior.

“The eclipse is part of the natural world and the animals around us are part of the natural world,” Cartmill said. “They are the creatures we share the world with and they have a lot of the same desires and needs that we do. I think something that is of profound curiosity to people is how many of our experiences are shared with the animals we share the planet with.”

More:Detroit’s last total solar eclipse was more than 200 years ago: What the city was like then

Social media and the Great American Eclipse

The Detroit Zoo’s spokesperson Sarah Culton declined to comment on its plans for the animals during the solar eclipse on April 8 other than to say, “Animal well-being is always our top priority. Our animal care team closely monitors the animals who call the Zoo home and responds to their needs accordingly. We do this every day — and will continue to do so during the solar eclipse.”

According to the February 2019 article, “Comparing Social Media Observations of Animals During a Solar Eclipse to Published Research,” in Animals, the 2017 solar eclipse strongly kindled curiosity in animal behavior during an eclipse and given the eclipse “occurred over a relatively populous region of the globe, with approximately 12 million people living in the path of totality — garnering a lot of publicity — many of whom own domestic animals. This immense viewership created a unique opportunity to gather a large number of animal observations simultaneously across the eclipse.”

Scientists turned to Facebook.

A total of 685 observations of about 48 different types of animals reacting to the 2017 eclipse were studied from the March for Science Facebook page discussion, the article said. The animals most frequently reported on social media reacting to the eclipse were invertebrates, including 11 types of insects (think crickets) and the most frequently reported behavior was vocalization increasing. While birds were reported to increase their activity and decrease vocalization. The most commonly observed mammals were dogs, which reportedly increased activity and vocalization during the eclipse.

The article states there are many reasons why a solar eclipse may spark behavioral changes.

“Not only is there a change in light, but also changes in air temperature and wind speed,” the article states. “It is possible that the brief changes in temperature and wind speed are sensed by animals and, in combination with reduced light, are interpreted as the beginning of nocturnal changes or large storms, potentially enhancing bird and invertebrate vocalizations as instinctive behavior.”

But it is stated, and Cartmill agrees, that the specific response by an individual of any species depends on their specific life history and behavioral patterns associated with various nocturnal changes or events that decrease light.

Vultures and bird reactions

The 2017 eclipse also inspired two animal behaviorists to study its impact on turkey vultures at the Joseph A. Sgaggero Memorial Park in Dover Plains, New York, on Aug. 21, 2017, as documented in a March 2018 article in The Kingbird, a quarterly journal devoted to New York State ornithology.

In the Kingbird article, the authors Steven Platt of Wildlife Conservation Society at the Bronx Zoo and Thomas Rainwater of Tom Yawkey Wildlife Center & Belle W. Baruch Institute of Coastal Ecology and Forest Science at Clemson University, state: “Turkey Vultures begin gathering above the roost shortly after the eclipse commenced.”

After about a 30-minute lull in activity, some, but not all, turkey vultures left the roost. What made the remarkable finding, the authors wrote, was that the birds started roosting even when it was still light and looked like a typical August afternoon.

“The fact that our observations occurred under conditions of almost full sunlight suggests that either Turkey Vultures were sensitive to even a slight reduction in light level or were responding to as yet unrecognized stimuli,” the authors wrote.

Then, on June 21, 2020, animal experts observed “clear and radical” behavioral changes in birds during another solar eclipse, according to an article in Egyptian Academic Journal of Biological Sciences by Sefi Mekonen of the Department of Biology, College of Natural and Computational Science, Debre Berhan University in Ethiopia. Mekonen wrote that before the eclipse the main activities of birds observed were foraging and courtship. But as the eclipse started, rooting increased.