Sea lions do have a natural predator that once kept their population in check--- man. That’s right the tribes once hunted sea lions on a regular basis. The problem now is that the tree huggers have a cow if you hunt them and the tribes would rather eat at MacDonald’s. Since we have removed hunting on these animals their numbers have gone thru the roof and are having a unnatural effect on the population of salmon that are trying to live in a unnatural world. This is why we as the dominate species’ on the planet must “manage it”. Managing does not include “letting nature take its course” that’s why we have forest fires, deer populations that eat them selves out of house and home (happened in co. in the late seventies) and too many sea lions. I think that the tree huggers and some of us forget that man is part of the ecosystem too.