Oh it is very like the alarm sound my hens make - so maybe it is a ladies thing - and it is what I tried but with less satisfying results!It's not a sound I've ever heard a rooster make as an alam call but it seems to work.
Now that I think about it, one of the Roadrunners made the noise and they all behaved like they did when I made the sound which is to freeze in place and look carefully around before concluding it is a false alarm and going about their business!