Mayflies have long been indicators of the ecological health of the lakes, rivers, and streams. The more mayflies present in water, the better the water quality.
But scientists from Virginia Tech and the University of Notre Dame recently discovered that a particular species of — burrowing mayfly — had a population decrease of nearly 84 percent from 2015 to 2019. The measurements, using radar, took place during the annual insect emergence events at Lake Erie, when the transition of almost 88 billion insects moving from the waterways to the air marks one of world’s largest annual insect emergence events.
Although it was previously impossible to analyze the emergence of the burrowing mayfly, researchers were finally able to do so by using meteorological radar data and new methods in tracking the presence of airborne creatures. By observing the swarms on a year-to-year basis, the data showed a shockingly simple trend: over the same timeframe and time of year, the mayfly swarms are growing smaller.
“This refined radar technology that allows for tracking and quantifying aquatic insect populations at such a large scale is instrumental in understanding land-water connections,” explained Sally Entrekin, an associate professor in the Department of Entomology in the Virginia Tech College of Agriculture and Life Sciences.
Read more at Virginia Tech
Image: Sally Entrekin samples a stream in search of aquatic insects, including mayfly nymphs. (Credit: Virginia Tech)