This one may only be of general interest to my fellow North American field recordists. There's a bird we hear *all*the*time* yet, when early in our careers we often confuse it with a "distant generator thumping". Yes. The Ruffed Grouse.
Also called the "Fool's Hen" for it's propensity for not running quickly away when approached, leading one to feel like you can catch it if you're quick enough. Inevitably it darts off just before caught.
During mating season, the male Ruffed Grouse declares its territory and availability by finding a log to sit on. On a period of every five to twelve minutes it rapidly fluffs its feathers and pounds the log to produce a low rapid thump that can carry for quite some distance.
It continues to do this for five to to twelve hours at a time if undisturbed. Making the only later evidence of its presence just a collection of drying fecal drops on the Chosen Log.
In most recordings it rarely rises above 100 Hz. When just 50 feet (15 meters) away, it still feels more like a thumping pressure than a sound you think you actually hear.
I was recently out recording for a few days when I heard the tell-tale thump. Later, on a walk around the campsite, I heard a disturbed rustle and just glimpsed a Ruffed Grouse hopping off its log. Confirming it with the tell-tale poop drops I though, "Here's my chance to show its more than just an amusing generator stand-in".
I snuck a pair of small omni microphones in around 1900, placing one about two feet above the poop and one off to the side, just in case it moved around. I hit record on my hidden recorder and wandered off to bed. I heard thumping throughout the night, so I was certain I got something. I wasn't quite prepared for a ten-hour performance, though.
This clip is from somewhere around 4am. Unfiltered, unmastered, no leveling. It’s merely time-edited so you don't get bored just... waiting... for... the... next... drumming. If you like that feeling of boredom, here’s the un-edited version: https://on.soundcloud.com/pOdK8uX8DZ5hjWuy4p
Channel one/ Left is the "side" omni, which also got a lot of the roominess of the log itself. Channel two/ Right was right on target and just a few inches above the bird's head.
For more info on Ruffed Grouse and other recordings, photos, and VIDEO, check out the Cornell Library's entry here:
https://www.allaboutbirds.org/guide/Ruffed_Grouse/
For the technically-curious, gear used: microphones and recorder. If you're really, truly interested, feel free to message me directly.
