Naelean 1968 (3) 8 May) covered > 1/2 mile in about 5 minutes of continual display. the display in its most intense form (seen when several birds were interacting) involves alternating series of the baird-like trill and a note that may be either je-jew or jew-et (there are variants of the note - not different attempts at rendition.). this latter note is remarkably like a white-rumped sandpiper - it has the same resonant quality. In the most intense display 7-10 baird-like trills were followed by 4-6 white-rump-like je-jews. In the complete sequence - a bird rises from the ridge and flies over the canyon with shallow, rapid wingbeats. the first series of notes may begin at a low elevation, but the bird continues to rise, then circles or ∞ slowly over the side of the canyon. the vocalizations are given from set wings - held slightly above laterally. thus flap - baird note series - je-jew series ; flap... i.e - each series of calling is interrupted by a period of silent flapping. In less intense display the je-jew or jew - it is given less frequently. I counted series of baird-notes up to 19 notes long - pause for flapping - then more baird-notes. the je-jew series may be occasionally