Any chance it is a snail or slug. A shiney slime trail should be visible.
Bush snails are way to small to do that much damage.
Ruling the above out the next chewing beasties that are suspects are grasshoppers or wood roaches.
It is a bit hard for me to see the damage clearly.
Go into the collection an hour after nightfall and look for the culprits, they should be out and about by then. Good luck!!
