Officials have been directed to cut water supplies to cities and farms by 5-7% to save several fish species.
California's rivers used to brim with trout, salmon, sturgeon and more, but the federal, state and local governments built a monumental system of dams and pipelines in the most populous state that turned a desert into productive farmland and left some rivers dry.
The state faces a water crisis and a third year of drought. Add climate change and a growing population to the mix, and the fate of some salmon runs looks untenable without change, the National Marine Fisheries Service said in a report ordered as part of a long-running court battle over the salmon. More from Peter Henderson's story for Reuters >>