My two parakeets both do this. Iv taken it to be a sign that they want out of their cage. My cockatiel also does this, but only in front of his mirror. After he does his singing and strutting, he will clasp onto his perch and flaps like a mad man. They are all flighted and always have been.
Then again, hes quite fond of grabbing onto the retired ceiling fan and making it spin while he flaps in place. All the while shouting "Wheeww! Whewww!" with each pass.
I think my cockatiel is a redneck hillbilly incarnate...










