Common Grackle

Many species of grackle are mimics, having the ability to reproduce some sounds they commonly hear around them; for those living in developed areas, car alarms are a frequently learned and reproduced sound.

[Rachel Holbrook]

I took lots of pics of them when in Texas once - they remind me of our UK magpies, full of character.

[Ralph Miner]

@rvm At first I thought it was a Brewer's Blackbird - but once I saw the color on the head I knew it was this pretty bird