One scrub jay is noisy enough all by itself.I was looking at some of the online bird info sites, and some have audio clips of the bird calls as MP3 files.
I downloaded one for the CA Scrub Jay onto my recorder, then put it on loop playback and played it into a battery-powered speaker set out in the yard.
One Scrub Jay high in the trees got curious, bobbed its head a few times, and then responded to the speaker's calls. Suddenly about six others showed up and it seemed some turf war ensued. Lots of racket and bird battles in the trees, which also got the neighbor out of her house to find out what their noise was all about. Maybe the recording was a "Call to arms?"
Guess bird calls do work.