Not going to help things. Read Song for the Blue Ocean regarding eco-systems and salmon habitat or fen Montaigne's Reeling Through Russia about the salmon poaching gold rush mentality on the Kola peninsula there.
Knock down the dam, clean up the rivers, leave the existing untouched watersheds alone, stop salmon harvesting at sea; etc. etc. etc.
The core problem w. any fishery; salmon, bluefin, flounder, whatever is malthusian. More and more people pressuring the same finite resources.
Gloomy thoughts on a gloomy Monday.