You're confusing conservation with animal welfare. They're two different goals which are often contradictory. You may be right that killing poor people would be

You're confusing conservation with animal welfare. They're two different goals which are often contradictory. You may be right that killing poor people would be a solution to poverty. But we don't do that because we think saving human life is more important than solving poverty. We could also minimize elephant killing by exterminating the species. That would ensure nobody ever inhumanely kills an elephant again. But preventing elephants being killed isn't our most important goal that we're willing to sacrifice everything else for.