EXAMPLES FROM THE WEB FOR CHURR
From twilight till grey does the fern-owl "churr" and fly through the night.
The death of that poor fellow, Churr, clings to him, say what one may.
I saw his mouth open and shut, he hollowed his hands round it, but the churr of the motor and the bees drowned his words.
The only note I have heard it utter is a kind of churr, like the call of the scarlet tanager.
c.1600, echoic of a grasshopper's trill. Related: Chirred; chirring.