There's no science that says that won't happen.
Like Bob suggests I could come right back at you and ask you for proof that removing all net pen aquaculture will bring back wild salmon in droves. I believe there's some onus on the snake oil salespeople like Fin to show this considering he is standing up in the House of Commons pronouncing this. Fin is coming out saying that the science is clear on this, but that's Morton's interpretation which deviates from reality.
There's increasing evidence that suggests that these issues are not as cut and dried as some may believe. Why do we go from records low Fraser Sockeye returns in 2009 and 2016 to a historical record return in 2010 and near average survival in between? Amongst poor returning Fraser Sockeye CUs there are some that return greater than brood. When some Pacific salmon species do poorly others return in exceptional numbers (i.e. Chum this season and Pink in other years) - why? Interior Fraser Coho numbers are looking better this year. Meanwhile, in the marine environment, we had this warm water blob that has existed off our coast since 2013 which we still do not know how or if this had any impact, especially when you have the inconsistencies I just mentioned. You then have a freshwater environment where juvenile salmonid assessment concentrates on certain areas intensively, but there's a big void in other areas where we really cannot say how many juveniles are outmigrating to the ocean. Additionally, during the Cohen Inquiry, it was shown that Sockeye survival in other adjacent areas to BC had done relatively poorly also - not just isolated to the Fraser.
As we get closer to aquaculture, critics that blame PRV for HSMI ignore evidence that not only shows that salmon injected with the virus do not develop HSMI, but that PRV likely existed here before salmon began here - with a distribution that extends from Alaska to Washington State. We know for a fact that PRV is found in asymptotic farmed and wild salmon. Of course, Morton still cannot prove that those transferred Marine Harvest fish that allegedly had PRV were indeed diseased.
Of course, Fin never considered any of this and instead decided to do his own narrative of the situation.