I'd have to say that one of the most popular sweet treats to come out of Japan is Pocky. While I don't normally eat it, I had to pick up a few boxes the other day when I saw they had Pumpkin at the local Marukai store. It was pretty good! I'm guessing they were going for a Japanese pumpkin flavor, kabocha, which is sweet when cooked.
Although I don't know if I would recommend giving Pocky to wild animals. I think there was a give-away for the little animal figures but not sure about this.