There's a myriad of silence around it. Some juries are still out. In my mind, it's not. They have introduced a couple of diseases. That's a recognized, known fact on the west coast. They introduced parasite loading that wipes the smolts out, basically. They load them up with lice to the point that they no longer survive.
On the actual farm footprint, underneath that farm, if you look at the sea floor before the farm goes in and you look at it a year later, you would think a nuclear bomb had hit it. It spreads out from that, but it's only such a limited extent.
Again, going back to the point, will removing all the farms make any significant difference when they're under this level of depredation? In my mind, no.