Susan, I never imagined that...must have been a hoot!
Watching the Birds Midsummer 2014
I was pretty surprised, that's for sure. I think it's probably stashing away sunflower or safflower seeds in there.
Critter, I didn't think birds re-used nests because they want to minimize the chances of mite infestations, but obviously that's not always the case!
I started a new thread: http://davesgarden.com/community/forums/t/1380032/
I added "furry friends" to the subject because let's face it, chipmunks and squirrels are so cute! The owner of the bird store from which I buy food showed me a photo of a regular visitor at his house: a Red Fox that comes to his porch to eat the remaining bird seed and drink from the bird bath!