Something Is Eating My Elderberry Bush

For the second year in a row, something has eaten most of my elderberries from the bush. I don't mind, as I can find plenty of elderberries in the wild and this bush attracts wildlife to my garden.

 It's hard to see in this photo, but this cluster of elderberries is nearly gone. I'm curious what is eating it. I can't imagine green elderberries taste very good!