Salmon return to the Klamath River

[Catherine]

The Klamath River in Oregon has been heavily dammed for many years. Four Hydroelectric dams have been removed. The salmon returned to spawn this fall. 
They made it past obstacles to spawning areas that have not seen salmon in over 100 years. 

https://www.centraloregondaily.com/news/...86887.html

Once the river was opened up, the salmon returned. I don't know how the fish knew the river was open, but they knew.
When we restore the land (or rivers), nature returns. Rewilding and restoration of habitat is the key to species survival and repopulation.
If we repair more rivers, the salmon numbers will increase. Since salmon are a food source for animals like Orcas, their return will help the Orcas to survive.
Even fixing one river will make a difference.