I agree with your definition of sustainability and I like how you related it to Solow’s. It is our moral obligation to preserve species for future generations and that is where Solow’s argument goes astray. However, whether we like it or not I think that farmed salmon is sustaining wild salmon to a point. Not necessarily in the vein of replacement as Solow would suggest, but in the fact that the demand for salmon cannot be met with wild stocks alone and farmed salmon makes up the difference so that we can protect wild stocks for the future. In other words, let them eat their farmed fish so that we can stil have wild salmon. Let’s just hope that we can find away to lessen or eliminate the burden it places on the environment.