Salmon in the ocean off the coast of California in 2024 will consist primarily of Central Valley hatchery fish ages two, three, and four. They were released primarily as sub-yearling smolts in 2021, 2022, and 2023 (born in the fall of broodyears 2020, 2021, and 2022 respectively).
Feather River Hatchery
The Feather River Hatchery released approximately 8 to 10 million fall-run salmon smolts in the spring of each release year. All were trucked to the Bay or coast, except for 1.5 million released to the lower Feather River in April of wet year 2023. My guess is that the number of the fishable salmon in the ocean that are 2-to-4-year-old fall-run Feather hatchery fish could be 500,000 fish in 2024, with 125,000 marked with an adipose fin clip. The hatchery also released another 6 million spring-run smolts in the three years – all marked. The total marked salmon in the 2024 fishable stock will likely be about 150,000.
American River Hatchery
The Nimbus Hatchery released 4 to 5 million fall-run smolts per year from 2021 to 2023. Nearly all were trucked to the Bay or coast. My guess is that about 50,000 of Nimbus broodyear 2020-2022 marked salmon will be in the fishable stock in 2024.
Mokelumne River Hatchery
The Mokelumne Hatchery released approximately 6 million fall-run smolts per year from 2021 to 2023. Nearly all were trucked to the Bay or coast. My guess is that about 100,000 of Mokelumne broodyear 2020-2022 marked salmon will be in the fishable stock in 2024.
Coleman (Battle Creek) Hatchery
The Coleman Hatchery released approximately 10-12 million fall-run smolts per year from 2021 to 2023. Nearly all were released at or near the hatchery. My guess is that about 25,000 of Coleman broodyear 2020-2022 marked salmon will be in the fishable stock in 2024.
Other Central Valley Salmon Hatcheries
The three smaller salmon hatcheries release about one million salmon smolts per year near the hatcheries, about half of which are marked. My guess is that about 5,000 of broodyear 2020-2022 marked salmon from these hatcheries will be in the fishable stock in 2024.
Klamath/Trinity Salmon Hatcheries
Klamath/Trinity has two hatcheries that release a total of 4-5 million smolts per year. I have not included them in this assessment.
Summary
My guess is that there will be about 330,000 marked hatchery salmon from the Central Valley salmon hatcheries in the 2024 fishable stock, not counting Klamath/Trinity or Oregon/Washington marked stocks that occur in small numbers off the California Coast. The number is similar in size to the NMFS/PFMC Sacramento Index that is the basis of salmon harvest management for coastal and inland salmon harvest (see chart below). Though the estimates are complicated and only crudely comparable, they are a reasonable basis for developing a 2024 fishery harvest strategy.
Recommendation
I suggest a harvest of up to 200,000 of the marked salmon only in a California mark-selective fishery in 2024. That is a total harvest similar to the average over the past decade, but with protection built in to minimize harvest of wild, natural born (unmarked) salmon and the unmarked portion of hatchery releases. There is concern for marked listed hatchery winter-run and spring-run salmon that would need consideration, but these fish are generally protected through seasonal and area restrictions. Regulations and monitoring specific to a mark-selective fishery would have to be put in place. Experience in the Pacific Northwest indicates mark-selective fisheries are a viable alternative to closed fisheries.