This Introduction is the first in a series of posts that summarize elements of my recommended plan for Central Valley salmon recovery. Central Valley salmon runs over the recent five decades have varied from a total near 100,000 to near a million spawners with an average of 200-300 thousand (Figure 1). About 90% of the salmon runs have been fall-run. Spring-run and winter-run salmon have declined and are listed under the state and federal endangered species acts. All four runs are supported by hatcheries that raise about 30 million juveniles per year for release to rivers, the Bay-Delta, and the coastal ocean. Each of the run types are made up predominantly of hatchery-produced salmon. A few small stocks are comprised mainly of wild salmon, while most runs have a small “wild” or natural-born component. Rebuilding wild salmon stocks while providing for historic levels of commercial and recreational salmon harvest is the dual program mission.

The total number of adult salmon produced in the populations includes escapement to the spawning rivers described above as well as adult salmon harvested in the ocean, Bay-Delta, and rivers, prior to the spawning runs. These estimates are of the human harvest (Figure 2) and do not include harvest by marine animals or illegal fishing. Human harvest rates over the past four decades have been 50-70% on average except in years when the fishery is restricted (2008-2010 and 2023 and 2024) (Figure 2). Government agencies often restrict harvest when the Sacramento Fall Run Index falls to near a target minimum of 122,000, a condition commonly referred to as “overfished.”

The goal of my recovery plan is to return total adult salmon escapement to near a million fish, with a further harvest of 500,000 adult fish. The harvest would focus on hatchery fish, while habitat improvements would focus on rebuilding wild, genetically pure populations and their critical habitat.

The primary tools of the proposed recovery program include hatcheries, wild salmon sanctuaries, improvements in water project management and infrastructure, habitat enhancements, and changes to fishery management. Hatchery programs would include “production” hatcheries to produce marked smolts for release for harvest and maintaining spawning populations in rivers that cannot sustain wild populations. “Conservation” hatcheries would support the protection, maintenance, and development of “wild,” “genetically-pure” populations.

The actions I propose are not radical or new: they have been included in many plans and program recommendations for decades.  Many have been successfully implemented on a small scale in the Central Valley or in other large salmon watersheds of the Pacific Northwest and Alaska.

Figure 1. Total Central Valley Chinook salmon escapement by run type 1975-2023. (Source: Grandtab)

Figure 2. Sacramento River watershed salmon population index 1983-2023. Source: NOAA Fisheries and Pacific Fisheries Management Council. Note there was no harvest allowed in 2024, as in 2023.