The population of the endangered Devils Hole pupfish, one of the world’s rarest fish, more than doubled over the past year. Wildlife biologists counted 137 Devils Hole pupfish during a National Park Service survey on Oct. 10— nearly twice the 77 fish recorded during the spring 2026 survey and more than double the 69 observed in fall 2025. The tiny blue fish, whose entire wild population lives on a shallow limestone shelf in a sinkhole within Nevada’s Ash Meadows National Wildlife Refuge, has struggled to keep its population over 100. … The Devils Hole pupfish was listed as endangered in 1967 under the Endangered Species Preservation Act, the predecessor to the current Endangered Species Act, which was enacted in 1973. Its population began to decline in the 1990s, following growing groundwater pumping.

Other fish restoration news:

• Bay City News: Bay fish still above limits for mercury, PCB chemicals, study finds
• KCRA (Sacramento, Calif.): Roseville community celebrates Chinook salmon’s return to Dry Creek
• Active NorCal (Redding, Calif.): Crews sank 750 trees into the Sacramento River this year on purpose, and 1,200 more are coming