"That's right, I'm talkin' to you."

"This feeder is mine.  Don't even think about coming near it!"

This cardinal spent 10 minutes putting on a show, letting everyone know that he mean business...  He jumped from perch to perch.  Squawked and sang, puffed and glared at anyone who dared enter the area.  He was definitely clamming the feeder... But funny thing... he never actually ate from the feeder.  After all that, he left without a single seed or nut.  
Go figure.