Strange Happenings

It's amazing what you can find in your own garden....I found this the day after Halloween. The mystery is though, how did it get there? I have a fairly large garden and this was half way up. If it had been thrown then surely it would have smashed?

I have a theory that the pesky little squirrels have found some chickens and pinched their eggs but could it have been a low flying pigeon that dropped one? Was it Rosemary, the telephone operator, Sarge or even Henry, the mild mannered janitor? Too many unanswered questions for my liking ;-) Any more ideas?