There have been studies done on escapes. The end result of a major escape would be that farmed salmon, which are a different species--they are Atlantic salmon, which doesn't belong on our Pacific coast—could injure our local streams, potentially breed, and take over.
There is no evidence that it has happened so far. On the list of impacts, we're concerned about that. We're concerned about it in the long term, but at the moment it's further down on the list of impacts that we're immediately concerned about. It's eliminated entirely if you move to closed containment.