What could be eating my brussels?

I mean the actual sprouts that are now developing on the stalks. Some of the small developing sprouts have been nibbled away at.  I know that despite being netted some caterpillars have got in as I found a couple of the leaves which have some damage on.

Would it be the caterpillars that eat the spouts or would it more likely be slugs? I'm going to pull the netting off tomorrow and have a really good look.