Hi Ken,
good observation on the heads, I also read that if the adult is a male it's beak line stops at the middle of the eye, and the female's goes just to the end of the eye or a little past it. I have to check this as I just heard of it recently.
Kit
Rockitglider
AKA: Kit O.
Nature Photographer, Model rocket builder, designer and flyer
Remote Control Gliders & Rocket powered Gliders as a hobby,
AUTOCAD engineer professionally for Fire Alarm Systems in Ft. Lauderdale Itnl. Airport (FLL) & PBIA as well.
Website:
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