There is, or should be, more to the "maximize economic benefit" idea. As the cost of fuel goes up, it is going to get more and more expensive (economic value) to chase salmon all over the ocean than to fish for them in the river of origin. Looking beyond simply dead fish, maybe we should look at how many pounds of fish are caught per gallon of fuel. Is there a better use for fuel than chasing fish?

The same goes for meeting the ecosystem need for nutrients. We need more fish on the spawning grounds. In same cases, not killing one species of salmon will benefit another species of salmon. In some other cases, the benficiary will be bears, wolves, mink, or who knows what. To have healthy ecosystems, we are all going to have to give up something. We can't have it all, everywhere.