Sage grouse can be cause for concern

The Greater Sage-Grouse as he performs his ritual strut. Males have an esophageal pouch, which is inflated by the bird as it sucks in air. Once the pouch is inflated, it looks like a greenish-yellow balloon. As the cock steps forward, he brushes his wing feathers against his stiff breast feathers, making a swishing sound. Then the male stops and abruptly releases the trapped air, emitting a low pitched "blooping" sound.