Charlie may be right. I googled " white-crowned golden-crowned" and got this
link which I found very interesting. I'm still looking at some others but
thought I would get this up quickly for anyone interested.
http://elibrary.unm.edu/sora/Condor/files/issues/v058n04/p0294-p0295.pdf

Joseph Higbee
Spanaway, WA
Mailto: jvhigbee at hotmail.com