1979 Ronald L. Mumme Sialia (Western Bluebird) Hastings Reservation, Monterey County, CA 17 July While eating dinner with Nancy Joste at Hastings Cabin around 1945, saw some interesting behavior in three juvenile Western Bluebirds. The bluebirds were perched on the utility pole in front of the cabin, and were mounting each other in rapid succession, very similar to pre-roost mounting in Acorn Woodpeckers. First one of the spot-breasted juveniles would mount a second for a few seconds, then the two would switch. I saw about 5-8 bouts of this before the three flew off.