I know these aren't native to our state, but if grubs are placed in a greenhouse, will the adult flys create their own new colony? I know they aren't good at flying, so I figure if they are stuck inside the greenhouse with a ready food supply for their larvae they might stick around. Does anyone have any experience with this? Or maybe a resource a might look at. They look tasty, and I want to feed them to my fish. (I might try a few too :))