This is a problem on the East coast as well. I remember being advised in the late '80s to get into acquaculture/salmon farming because it was an up and coming career opportunity. Salmon farms sprang up in many areas including the Bay of Fundy area into which flows the river I grew up beside, the St. John. Once a mighty salmon river, it has been closed to salmon fishing since the mid-90's. In addition to two dams built on it in the '50s and 60's, the acquaculture pens with the disease and waste they proliferate are much to blame for the decimation of the once plentiful runs of wild Atlantic salmon.