You bet! Whatever side of the fence you are on everyone is entitled to their beliefs, while i am not saying fish farms are solely responsible for the decline in wild salmon stocks all the signs point to the the fact that they are in someway connected .. Even getting the fish farms moved on to land would be a big win for wild salmon.
You should be careful with the argument "everyone is entitled to....."
It is typically used as an attempt to create a false equivalence between a valid researched finding, and a laymens opinion.
While everyone is entitled to have an opinion, opinions are anything but equal. Ms Morton preys on the publics need for shocking information, and uses her status to commit the "argument from authority" fallacy.
While she is a marine biologist, and she has some published work, she makes claims that are far outside of what she has published, and can be verified. This is very poor science, if she were still associated with a university it would most likely result in academic misconduct findings.
Just because you are expert on topic A does not mean that anything you say about topic A is correct. You should very carefully stick to only what you have published and other scientists can verify for themselves
The whole conversation about fish farms is typically a bunch of people who haven't conducted any research having their own opinions, and thinking that they are equal to what years of research have found. Morton takes shocking photos and then makes very specific damaging claims, mostly unfounded and exaggerated. the worst sort of junk science and bullying.
I personally have the uninformed opinion that fish farms should only be in landlocked facilities, but I am aware that I don't have anything to back up my opinion, just anecdotes and opinions.
There are many rules and fallacies to making a good scientific argument, and this particular topic seems to draw out all of the fallacies from both sides, with very little valid science involved