Dammed to Extinction (2019)

For eons a oneofakind population of killer whales has hunted chinook salmon along the Pacific Coast of the United States For the last 40 years renowned whale scientist Ken Balcomb has closely observed them Hes familiar with a deadly pattern as salmon numbers plummet orcas starve The orcas need roughly a million salmon a year where to find a million fish The solution says Balcomb is getting rid of four fishkilling dams 500 miles away on the largest tributary to what once was the largest chinook producing river on earth