Like many other Americans this past week – I took part in the nationwide migration to see the Great American Eclipse! Along with some friends I made the 12-hour journey from where I live in northern New Jersey to east Tennessee in order to witness eclipse totality. We ended up at Melton Hill Dam Campground and Park where we experienced around 1 minute 45 seconds of darkness during peak totality.
It was so exciting to see people across the country join together to witness a rare and beautiful natural phenomenon. Across the path of totality, many schools had closed for the day and others were utilizing the eclipse as a teaching opportunity. Where I was, families had set up camp for the day, excited to view the eclipse and no one, young or old, seemed immune to the awe-inspiring experience of eclipse totality.
As predicted, during the eclipse it got darker and cooler. As it got darker, the chirping of insects, like cicadas and crickets grew louder. I am also pretty sure I saw a bat fly by during peak totality! Humans were also behaving strangely – hooting and hollering while gazing at the sky in their eclipse glasses!
So how did other wildlife respond to the total eclipse?
To gain answers to this question and many other eclipse-related questions, scientists and citizen scientists around the country spent their eclipses collecting data. Maybe my observations are indicative of how bats or katydids respond to eclipses but maybe they were just random events with no connection to the eclipse itself. However, if across the country, hundreds or perhaps thousands of other people observed similar phenomena during the eclipse, we have a much better understanding of how these organisms are likely to respond to similar celestial phenomena.
Previous eclipses had yielded some interesting observations like orb-web spiders tearing down their webs, birds that cease chirping mid-song, ants and honeybees retreating back to their nests or hives and nocturnal animals becoming active mid-day. Captive chimpanzees were observed clustering together high up on their climbing platforms.
These individual observations are important, but in order to be scientifically meaningful, there needs to be replication and rigorous protocols that allow observations be compared to one another. Because total eclipses are rare events and often occur in remote locales, there has been little opportunity for the quantity or replication of observations preferred by scientists to answer the big questions.
Thus, from a scientific perspective, The Great American Eclipse provided an excellent opportunity to collect data on a variety of phenomenon (see this Science Friday article). As this eclipse was visible (to some degree) by most Americans the potential for citizen scientist contributions was unprecedented, due to its path through many well-populated regions of the US as well as the ubiquity of smart phones enabling accurate recordings and easy sharing of observations.
One effort, Solar Eclipse 2017: Life Responds, is a partnership between the California Academy of Sciences and iNaturalist.org – a smart phone app that can be used to record and share observations of wildlife. Life Responds had a goal of documenting how animals and plants responded to the eclipse across the United States. Over 600 people participated across the country providing over 2000 observations of more than 400 species.
Some observations from the 2017 eclipse included frogs calling, bats swooping, and more insect activity such as crickets and katydids chirping. Some plants opened or closed their flowers and fish began to feed. Many diurnal species went quiet during the eclipse and some nocturnal species became more active. Many species seemed to be uneasy about the unusual mid-day darkness. Equally important are the observations of organisms, like the American Bison, that did not seem be phased by the eclipse at all.
Many zoos also invited citizens to join their zoo staff in making observations of animal behavior during the eclipse. At Riverbanks Zoo in Columbia, SC where totality was around 2 minutes 30 seconds, people observed prey animals, like giraffes, exhibiting anti-predator behaviors, like vigilance and huddling together. Some animals, like the flamingos and the siamang apes gave out loud agitated calls as the eclipse began quieting down during totality. For more see videos here and here. Similar behaviors were noted at the Memphis Zoo with many animals acting as they would normally do at dusk and then returning to normal after the eclipse was over.
Why do organisms respond to the eclipse?
This is a harder question to answer – as discussed above the rarity and ephemeral nature of eclipses make it hard to perform the needed experiments that would determine causality of behaviors or responses of wildlife. However, many scientists assume it is because some organisms have evolved to respond to environmental cues, like light or air temperature. For these organisms, the coming of day or night, as signaled by a change in light or associated changes to air-temperature, trigger specific behaviors such as those related to foraging or safety. For example, nocturnal organisms may be more likely to be active during an eclipse because this is when they feed. Diurnal organisms may become quiet and show anti-predator behaviors such as huddling together in same-species groups or increased vigilance because nighttime is when they are at risk of predation.
So kudos to the organizers and participants of citizen science projects like those described above and others like them! Citizen scientists provide power to science through sheer numbers. Alone each of us may make anecdotal observations but together all of these observations are data. Science requires replication in order to gain access to major truths.
I look forward to seeing the results of these citizen science efforts as they are analyzed in the coming year! With this new knowledge, we will then be able to better to design tests for why these organisms respond the way they do – and maybe create experiments for future eclipses. See you out there in 2024 during the next great American eclipse!
Did you participate in citizen science efforts during the Great American Eclipse? If so, please share your experiences in the comments section below!