As others have said, don't rule out the animals. They are expert fruit pickers with millions of years of evolution built into their tiny hands and teeth. They can easily take food without damaging the plant and they usually don't eat it nearby (it attracts predators, who know where to hang out...). I used to have a pear tree outside my window at work and every fall I'd watch the pears mature and then, POOF, in a couple of days hundreds of pairs would vanish in the hands of squirrels. It was pretty cool to watch.