I'm not trying to be evasive here, but I think what I would say is any species—when you understand a bit about its relationship with the environment in which it operates—indicates something about the state of that ecosystem.
As I said earlier, in the case of Pacific salmon this year, if our estimates are at all accurate, it looks like the current year class that's returning this year in 2014 has experienced relatively good conditions in the ocean that have allowed them to be productive and to survive, and also benefited from having a very large year class to start them off. There was very high production of small salmon from the 2010 return. So in that sense I think it is an indicator of a certain set of environmental conditions.
I think, though, like we are discussing with some other species, an ecosystem might be favourable to one species but not so favourable to another. Each type of animal in the ocean, and it would be generally true, has a set of environmental conditions that favour their productivity and others that don't.
I wouldn't jump to a conclusion about any one species, but certainly for Pacific salmon right now it looks like that ecosystem has been productive in recent times.