Even now, I have three bags of sugar in the cupboard! Our sugar bills were rivaling our vet bills for a while...so yes, I'd say sugar stocks would be a good investment!
The adults are hard to tell apart, LP--the fems all look the same, give or take the length of the neck and the condition of the feathers; and the males all look the same, too, give or take the same things. Adolescent fems all look the same. But adolescent males have different necklace bead patterns so they can sometimes be told apart.
I can usually tell when migration begins because the adult birds I see are very nervous when I approach. Since the local adults grow very tolerant of me, the nervous birds must be strangers, meaning that the locals have moved on and new adults are passing through. Otherwise, everyone looks so much like everyone else, I'd never be able to tell.
Chris, I'm ecstatic that you were able to download the pics!
Some of them are a little bigger in size than I usually post.