Most people identify the Pacific Northwest with salmon, but, in fact, there are more than 30 kinds of salmon, steelhead and trout native to California. These iconic fish once supported fisheries all along the coast and in our mountainous interior, but their numbers are disappearing. As my colleagues at the University of California at Davis and I recently discovered in a research study and subsequent report, 65 percent of the remaining species of our native fish are in danger of extinction within this century, if not sooner.
For nearly 40 years, I have been chronicling our state’s native fish. This new report is one culmination of that work, and although the news is grim, I have seen bright spots of recovery over the decades and have come to appreciate the resiliency of our salmon and trout.
In 1970, I recorded salmon spawning in the San Joaquin and Kings rivers, where they had not been recorded for 25 years. These fish were wiped out when the Friant Dam diverted the flows of the San Joaquin. Yet when the dam spilled, as it did in 1969, a few fish came back and spawned successfully. While this was a one-time occurrence, their demonstrated resilience became a basis for a court-ordered restoration program to bring chinook salmon back to the San Joaquin.
Later in that decade, I surveyed the McCloud River, a tributary to Shasta Reservoir, in part to look for bull trout, a cold-water predator. My team found no bull trout during two years of intensive sampling, but finally, on the last day of the study, a graduate student caught one 18-inch fish, which he tagged and released. That was the last bull trout recorded from California. I hope I am never involved again in a “last fish” study, but our findings indicate that this could happen all too easily.
I have seen some of the few remaining spring chinook salmon holding in their deep summer pools in three small tributaries to the Sacramento River, knowing they once numbered in the hundreds of thousands. Likewise, I have snorkled the pools of coastal streams in the redwoods and observed some of the few remaining juvenile coho salmon, remnants of the thousands that once existed there.
But I have also looked at streams flowing into Goose Lake, in Modoc County, and observed the remarkable recovery of Goose Lake redband trout, thanks to close cooperation between ranchers and fish chinook salmon have responded to the restoration of flows in Putah Creek and are once again spawning there.
But the fact remains that many of California’s salmon and trout are facing extinction, with some of them already formally listed as threatened or endangered by the federal government. You don’t have to look far to see why. The Shasta River, a tributary to the Klamath, once supported combined runs of chinook, coho and steelhead of more than 100,000 fish. Today, most of that river is too warm to support these fish because the precious cold water that bubbles from springs is diverted for irrigation. The water that returns is warmed by its flow over pastures and fields, rendering it unsuitable for salmon and steelhead.
The damage to the Shasta River – and other prime fish habitat – can be reversed. But re-creating a sustainable environment for fish requires efforts from individuals, organizations, and state and federal governments. As individuals, we can help by using less water in our homes and businesses, and by consuming fewer products that are water intensive to produce. But we also need to better fund and empower our conservation agencies to take protective actions that keep our native salmon and trout from falling further towards extinction.
In order to survive, our native fish need clean, cold water flowing through healthy watersheds, including places dominated by humans. Incredibly, and against overwhelming odds, some of our native salmon and trout still swim in streams from Southern California to the Oregon border and east to Nevada. They persist in dwindling numbers, but if we make the effort, they can come back to reclaim their rightful place in California’s natural heritage.
Dr. Peter Moyle and study co-authors Joshua Israel and Sabra Purdy are associated with the Center for Watershed Sciences at UC Davis. Read the report “SOS: California’s Native Fish Crisis” at www.caltrout.org.