Underwater “drumming” of the Freshwater Drum (Aplodinotus grunniens). 6:40pm, 9 June 2015, Beaver Creek in Knox Co, Tennessee. © Lynn Faust.

It all began in April of 2015 when Lang posted his hydrophone recording of the underwater calls of Pickerel Frogs. That amazing sound track reminded me (only slightly) of the booming, roaring sounds that have accompanied my summer swims in Beaver Creek in Knox County TN for the past 40 years. Beaver Creek flows into the former Clinch River (now TVA’s Melton Hill Lake) and is just a stone’s throw upstream from where the Manhattan Project occurred during WWII (yes, I suspect after all these decades of swimming in these waters, I might glow in the dark, just like fireflies).

We had always assumed they were male Freshwater Drum fish (Aplodinotus grunniens) sounding their mating calls (referred to as “drumming”) in our murky water each June, but we had never actually SEEN the callers. Now with Lang’s frog recordings, I began to doubt our long held, but non-confirmed, belief that fish were making these eerie snoring sounds. Next, in my quest to determine once and for all whether I was listening to fish or frogs or maybe even our local oft-reported “skunk-ape” or smaller “skunk-monkey”, I stumbled on Bob English’s wonderful Frog and Toad ID page, which has information and recordings of all the Tennessee frogs and toads. Now I was doubly confused because my Beaver Creek rumblers sounded suspiciously like the rare Gopher Frogs described and recorded on the LEAPS site.

By June, my Beaver Creek growlers were really going strong. I determined to record them so someone more knowledgeable than I could positively ID them. Little did I know how expensive and difficult to obtain hydrophones are. I have zero technical ability and was too tight to buy a real hydrophone, so I fashioned one out of an old balloon, a ponytail holder, a cell phone headset, duct tape and of course, a ziplock bag (see pic). The growlers appear to gather in larger numbers in certain areas of the creek, so there I was treading water frantically while trying to keep my voice recorder out of the water with one hand, yet holding my balloon covered microphone under the water with the other hand.

Eventually I realized my cell phone recorded better than my older voice recorder. I also came to accept that it was a matter of time until either I drowned or dunked and ruined the entire shebang. So, I switched to the kayak and my cell phone, both of which enabled these recordings. Though on peak evenings I can hear the drum through the thin sides of the kayak, it is best heard and experienced while swimming on your back gazing at the lovely green water or forested shoreline or the burning sunset with your ears submerged entirely.

Later, fish expert and friend David Etnier and audio recorder Rodney Rountree, along with Bob English, confirmed these were indeed Freshwater Drum male courtship calls. My hope is in the future Lang will use his superior skills to do better justice to these otherworldly drum symphonies.

It occurred to me then as it does every time I listen to one of Lang’s new recordings how little we know or understand about our fresh (and salt) water underwater world, even when sitting in a boat right above. Heck, even the above ground sounds blow my mind: Porcupines sounding like groaning women, beavers cooing in the most precious way, singing lovesick turtles and on and on. Thanks Lang!

HOW DOES THE DRUM FISH MAKE SOUND?: The Freshwater Drum doesn’t have vocal chords like we do. Instead, the fish produce sound with a special set of muscles in their body cavity that vibrate against the swim bladder, the bladder acting as a resonation chamber. Only mature males produce the drumming sound, and it is assumed to be linked to spawning.

About the Author: Lynn Frierson Faust, a lifelong naturalist with an inordinate fondness for fireflies, is equally taken with almost any wild thing that croaks, crawls, climbs, flies, swims, sings, chortles, leaps, gallops, hops, slithers or twinkles in the sky. She is also passionate about teaching reading to struggling readers and mentoring at risk children. She is at home in the green gentle hills of East Tennessee with her husband Edgar. Their three grown sons and two fine grandchildren all share her enthusiasm for our natural world. Her peer reviewed book on fireflies (750 color photos covering 70+ species), the first of its kind, will be available for early order Sept 2016 and on the shelves by early 2017 from University of Georgia Press: Fireflies, Glow-worms and Lightning Bugs! Identification and Natural History of the Fireflies of the Eastern and Central United States and Canada.