I don't have red-winged blackbirds in the yard on a regular basis anymore. This year for the first time I saw what the immature males look like, and wasn't sure what I was seeing at first. Plus it wasn't just one, there was a group of four or five and all a little different looking. I only saw them the one day though.
For a couple of years we had a mature male blackbird hang around for part of the year at the feeder. He would regularly let out the ear piercing call which absolutely terrified my poor old dog. She would run for the house and be shaking like a leaf. I finally had to stop putting out food for a while and shoo it away, because the dog was a nervous wreck.