Absolutely, any species that is a threat to the welfare of the indigenous strains trying their hardest to sustain themselves despite what we do are the problem.
In the native trout waters of the northeastern US smallmouth and largemouth bass have been illlegally or legally (or naturally) introduced into waters where wild trout are decimated.
Lampreys invaded the great lakes, even exotic weeds are chocking waters around the continent. Zebra mussels, the list goes on and on.
The key point here is that while big business (salmon farms) profit, the wild strains of many species suffer. If we are in fact the stewards of the resource we need to be very concerned regardless of the endeared species or those which threaten them.
IFFF Certified THCI @ 2005
Capeflyfisher Guide Service
Island Hopper, Guitarist, Incurable Dreamer
and Founder, Worldwide Flyfishing Forum