though it looks kinda like a turd, I dont actually think its a bird turd. The seeds look whole in the shells still, my guess is that its a piece some sort of parrot or squirrel treat. Do your neighbors have parrots? I know my macaw would have no problem at all flying off with a piece of something that size. Of course if theres a loose large parrot flying around, who ever lost it is going to pretty upset.