Another One

Another sage grouse from yesterday. This one shows the inflated esophageal sac. From Animal Diversity Web:

“The display of male Sage grouse consists of struts and tail-fanning. Also, he will inflate his esophageal sac and display the olive-green gular sacs concealed under his feathers. Another component of the display is when the male flaps his drawn wings to make a “brushing” sound and releases air from his esophageal sac to make a “plopping noise” (sounding like a large rock dropped into deep water).”

I was having a hard time trying to describe the noises they make, but the above description is pretty apt. There were 30+ birds making those sounds, so it was incredible to hear.