David Suzuki seems like a reasonable person to me. I do not think he would go out of his way to make a big deal out of something unless he had a good reason.
“Additional” sea lice (caused by fish farms) has a “negative impact” to natural systems or it does not. Just because a handful of people decided it is acceptable doesn’t make it so.
My opinion is this: nature was managing this for many, many years before we got here, and I am pretty sure her plan did not include nets full of farm fish in the ocean.
To me that is evidence enough that the sea lice problem (caused by fish farms) is significant enough to warrant replacing current fish farms with land-based methods. You simply can’t account for every variable enough to assure that you are not causing damage.
Land-based farms could be controlled a lot more accurately than ocean-based ones. I think until we have a better understanding of our natural systems than we currently do, it is logical to do things on the side of caution.
Farming fish in ocean waters does not fall on the side of caution because there are too many variables that you can’t account for. Variables like long-term effects of chemicals used, impacts of sea lice to which evidence at present is conflicting, contaminated water due to so many fish being in one enclosed space, fish escaping and possibly reproducing with natural stocks.
All these things plus any number of unforeseen ones, are having impacts that no one can say for sure, but may have lasting and damaging impacts to the health and well being of the salmon, especially as the number of farms increases.
The problem with many of these things is that the effects of them will not be seen for a long time after there are many farms out there. We think everything is going along fine and all of a sudden an impact that we could not predict occurs.
It is for this reason that these farms are wrong and I challenge anyone to prove we can manage salmon better than nature can.
In addition, nature did not intend for so much consistent and ongoing destruction to streams and spawning grounds, so it seems logical to assume that is a huge human blunder as well.
Also nature did not intend for trees to be cut down in mass scale like clearcutting, which we now know to be very hazardous to watersheds.
I also feel that it is reasonable to conclude that mining gravel out of a stream, especially where salmon migrate, is damaging and having a negative impact on that natural system.
Nature does not manage itself the way we do, so it is logical to conclude that we are doing it poorly.
Until someone provides us with evidence that shows we are able to manage a resource as good or better than nature, it will continue to be my view that we are on a slippery slope to which the destination is unknown.
It is also my view that whatever kind of management system we implement, it should be one that provides the least amount of environmental impact as is humanly possible. We should take the same care and planning as the people who put rockets into space. If that kind of thought was put into our environment we would probably be in a lot better shape than we are now.
If I am misguided and it turns out that nature in fact can not manage itself better than humans, and you provide irrefutable evidence that this is the case, then I apologize.