On August 21, 2017, at 16 points along the path of last year's total solar eclipse, tiny microphones--each about the size of a USB flash drive--captured a unique biological phenomenon. As Earth fell into complete darkness, the bees stopped buzzing, according to researchers at the University of Missouri.
"Getting dark in the middle of the day is not something that happens in a bee's normal life." said Candace Galen, professor of biological sciences in the MU College of Arts and Science and lead researcher on the study. "It's a behavioral miscue. Here darkness is a cue for night, that a bee is familiar with, but it's coming at the wrong time of the day. Did they use it as a cue or not, even if it is completely out of context? What we found is yes, they do."
Millions of Americans paused that August afternoon to watch the eclipse. As it passed overhead, MU researchers buzzed into action assisted by approximately 400 people--scientists, volunteers and elementary school students and teachers in Missouri, Idaho and Oregon, including over 200 elementary school students and teachers from Columbia Public Schools in Missouri--gathering audio data on the behavior of bees. At each of the 16 locations, the microphones were placed near bee-pollinated flowers and away from human-generated traffic.
Previous research conducted on bee behavior notes that bees commonly fly slower at dusk and return to their colonies at night. In this study, researchers found that while bees completely stopped buzzing during totality, they continued to fly during the periods of reduced light that occur in the phases of a partial eclipse.
"It's a soundscape," Galen said. "What we have is a buzz that is longer. Either the bees were flying more slowly or making longer flights."
The study, "Pollination on the Dark Side: Acoustic Monitoring Reveals Impacts of a Total Solar Eclipse on Flight Behavior and Activity Schedule of Foraging Bees," was recently published in the Annals of the Entomological Society of America. The work was supported by a Julena Steinholder Duncombe Mini-Grant from the American Astronomical Society. The content is solely the responsibility of the authors and does not necessarily represent the official views of the funding agencies.
Samuel Holden and Michael Axe, undergraduate students at the University of Missouri, and Zachary Miller, Austin Lynn, Levi Storks, Eddie Ramirez, and Emilia Asante, graduate students at the University of Missouri, coauthored the study. Other collaborators include David Heise, associate professor of science, technology and mathematics at Lincoln University; Susan Kephart, professor of biology, and Jim Kephart, director of information services, at Willamette University in Oregon.