As the numbers of Snowy Owls increase, some of you may be tempted
to try your hand at assigning owls to age class and gender. It's
not as straight forward as you might think.

http://elibrary.unm.edu/sora/JFO/v051n02/p0149-p0160.pdf

Based on the key provided in the above paper, I can say with some
confidence that all the South Jetty of the Columbia River birds
are youngsters (the mottling on the coverts being fairly obvious
on all three birds). The lack of barring on the sides and back
of the head suggest that all three are male, but I have to say the
gender determination in young owls is a bit squishy in my view.

--
Mike Patterson
Astoria, OR
celata at pacifier.com

Christmas Bird Count Calendar and FAQ for Oregon and Washington
http://home.pacifier.com/~mpatters/cbc/cbc_WAOR_reg.html