But where dams can't be torn down (which is, admittedly, in quite a few places) there's another way to help fish spawn: elevators and ladders. A fish elevator in the Connecticut River, for example, lifts thousands of fish over the Holyoke Dam each year. In 1967, about 19,000 shad rode over the dam; by 2012, that number had swelled to 500,000 fish.
4. Salmon carpool to the ocean in the back of a semi.