A Solar Eclipse's Effect on Biota
Amy He ’25 and Lucia Zhang ’25
Ellen Chen ’25
On April 8th, 2024, a total solar eclipse passed through North America, casting darkness over parts of Mexico, the United States, and Canada. Solar eclipses, on average, occur somewhere on the Earth every 18 months but only occur once approximately every 375 years again at one particular location on the Earth (Bernardi, 2024). Its rare occurrence, however, does not diminish its impact on nature. In fact, solar eclipses affect the natural world in particular and intriguing ways, disrupting the typical behaviors of animals, insects, and plants that depend upon the sun to regulate their activity throughout the day.
The Earth revolves around the sun; similarly, life on this planet revolves around the light-dark cycles posted by sunlight. In a study conducted in 2017 at the Riverbanks Zoo in South Carolina, 75% of animals observed exhibited some form of change in behavior in response to the August 21 total solar eclipse (Hartstone-Rose et al., 2020). Eight of the thirteen species studied demonstrated a behavior change to engage in their typical nighttime behavior. For instance, the African elephants approached their barn enclosures in preparation for rest. However, many others showed signs of distress and confusion. In zoos, a male Western lowland gorilla charged toward the glass during the eclipse, and a giraffe paced around his enclosure, “swaying his neck and body back and forth” (Hartstone-Rose et al., 2020). In the wild, bird activity was observed to slow down. Cecilia Nilsson, a researcher at Lund University in Sweden studying bird and insect movement, proposes that birds could attribute the darkening sky to a gathering storm that is dangerous to fly into (Ram, 2024). Yet, due to their rare occurrence, it is difficult for researchers to draw complete conclusions on the patterns exhibited. However, it is undeniable that solar eclipses prompt apparent disruptions to animal behavior.
Similar to animals, the occurrence of a solar eclipse impacts insect behavior. Upon solar eclipses, while frogs and crickets begin singing as a part of their nighttime routines, cicadas, who usually sing during the day, stop. More specifically, researchers at the University of Illinois and Barry University have studied desert cicadas, concluding that these insects suddenly stop making noises once the sun is half-covered in a solar eclipse. They noticed that the cicadas had stopped calling for forty minutes until after the total eclipse, and the sun was, once again, half-covered. The researchers found it interesting that the cicadas changed their behavior without being completely dark, leading them to believe that they “require the heat to work up the energy necessary for their constant calling” (Bug Busters, 2017). When it drops below a specific temperature, the cicadas do not sense a change in sunlight; instead, they lose the ability to continue calling. Additionally, honeybees return to their hives and stop foraging for nectar and pollen, while spiders take down their webs only to rebuild them once the sun reappears, both aspects of the night routines for the respective insects (Bernardi, 2024; Bug Busters, 2017). Some researchers have found that the bees’ return to their hives can be attributed to the change in environmental light overriding their internal circadian clocks (Johnson, 2024).
While humans stare in awe at the sun’s disappearance during a solar eclipse, animals and insects react fascinatingly in response to light changes, temperature, and environmental stimuli. However, it is also important to note that solar eclipses are not the only factor that causes disruptions in biota behavior. Due to human-caused environmental changes, the natural behavioral patterns of many wildlife around the Earth have been disrupted. For instance, light pollution has disrupted the migratory patterns of sea turtles and birds and the circadian rhythms of wildlife living near urban areas (Chepesiuk, 2009). Therefore, while solar eclipses are rare and may interrupt our lives occasionally, we should strive to protect and advocate for those whose lives are constantly threatened and disrupted by human actions.
References
Bauer, M. (2024, April 1). UF/IFAS Q&A: Why do insects behave strangely during a total solar eclipse? News.
Bernardi, D. (2024, April 2). Experiencing the Solar Eclipse From an Animal’s Perspective. SU News.
https://news.syr.edu/blog/2024/04/02/experiencing-the-solar-eclipse-from-an-animals-perspective/
Bug Busters. (2017, August 17). Do Solar Eclipses Make Bugs Do Strange Things? Bug Busters USA.
https://bugbustersusa.com/2017/08/17/do-solar-eclipses-make-bugs-do-strange-things/
Chepesiuk, R. (2009). Missing the Dark: Health Effects of Light Pollution. Environmental Health Perspectives, 117(1).
https://doi.org/10.1289/ehp.117-a20
Hartstone-Rose, A., Dickinson, E., Paciulli, L. M., Deutsch, A. R., Tran, L., Jones, G., & Leonard, K. C. (2020). Total Eclipse of the
Zoo: Animal Behavior during a Total Solar Eclipse. Animals, 10(4), 587–587. https://doi.org/10.3390/ani10040587
Johnson, C. Y. (2024, March 27). Birds, bees and even plants might act weird during the solar eclipse. Washington Post.
https://www.washingtonpost.com/science/2024/03/26/total-solar-eclipse-animals-react/
Ram, A. (2024, April). No, birds won’t fall out of the sky on April 8. CBC.
https://www.cbc.ca/news/climate/eclipse-animals-birds-bees-zoos-1.7157967
