California's native fish are in serious trouble, a new report warns. Unless things change, nearly half of California’s salmon, steelhead, and trout species will disappear within the next 50 years and 74% within the next century, say the scientists from the University of California, Davis, in a news release. They cite an array of causes, including the broad one of climate change, but say other factors are at play—including thirsty marijuana crops thanks to legalization, reports NPR. Chemicals used on food, wine, and marijuana crops are also polluting waterways, which become shallower as water is pumped out for irrigation. Meanwhile, dams are cutting off fish runs, per KCRA, contributing to a precipitous drop in the number of Coho salmon spawning in coastal streams over the last 75 years. Prized Chinook salmon also are at risk.
The report is a follow-up to one published in 2008 that found five of 31 genetically distinct fish species in California faced extinction within five decades. That figure has now risen to 14 species, with 23 on track to vanish by 2117, says lead author Peter Moyle, who calls the report "an alarm bell." It shows "we must act now," adds a rep for conservation group California Trout, which contributed to the report. "Declining fish populations indicate degraded waters, which threaten the health and economic well-being of all Californians." What to do? The report calls for the removal of some dams, the conservation of spring-fed streams, and the restoration of flood plains and coastal marshes, which serve as key food sources, reports the San Francisco Chronicle. (Read more California stories.)