Stopped by Kroger on the way home and the parking lot was occupied by thousands of grackles. Hundreds of cars in the lot, and each had its platoon of grackles walking around it on the ground or perched on the hood and roof, and dodging to a new spot every time a car or person walked by. Squawking loud enough to pierce the eardrums. Looked like they were setting up for a remake of The Birds.

This will give you an idea of the sound:

Grackles in Texas Parking Lots