As I understand it, you'd like me to comment on whether sea lice is just one of the factors that could be causing problems for pink salmon; I'm just saying “pink salmon” because that's really the only one on which much work has been done.
Let's put it this way. My opinion and what most scientists are writing in their research papers are the same, which is that there are many threats to salmon. Many of them interact. We don't know quite how the interactions work, but of course you would not be a good biologist if you didn't acknowledge the fact that usually these things are a combination of factors. There are an awful lot of things that have been shown to affect salmon populations.
In the United States, for example, they have a slightly different situation with their salmon, and they have what they call the “four Hs”. Let me see if I can remember: harvest, hatcheries, and hydro power. What's the other one? It's habitat, of course. It's loss of habitat.
It's a little bit different here in B.C. We don't have the big hydro-power developments they have. But on the other ones, as well as things like climate change and contaminants that come floating across in clouds from smelters in Asia, those kinds of things have all been shown to affect population strength in salmon. It's highly unlikely that it's only one thing. Again, the great thing about the precautionary principle is that it says there might be 10 different things, but that doesn't do us much good when we're trying to create policy here or trying to make legislation.
By the way, I really do see your point of view about having to rely on a bunch of waffling experts who are trying to protect their positions. I do see your point of view. I do try to write for the public, to make it intelligible and strip all the jargon out, but the precautionary principle also says there might be 10 different things that are causing a problem. Which ones can you actually do something about?
In this case, there are things that can be done about harvest. There are things that can be done about some of the hatchery effects on wild salmon. There are some things that can be done to give them back some habitat. There's not much we can do about climate change in the timeframe that will affect salmon--and it definitely will--but there are also things that can be done about sea lice.
If we suspect that the harvest is a problem, we cut down on the harvest. We may not be able to actually prove that, strange as that may sound. It's not as cut and dried as that, but we suspect it pretty strongly, so we'll cut down on the harvest.
If we suspect strongly that sea lice are a problem, we'll do something about them. I believe that's happening with the kind of integrated management that Bill Pennell has referred to.
So really, I don't have an opinion that's any different from what most scientists are saying. We live in an ecosytem. There are all kinds of influences on them, and yes, there are a lot of things that are damaging to salmon. Sea lice is one of them. It may be one that we can do something about more easily than we can for some of the others.