Results of the 2020 fishing season in California reveal a return to the reduced population levels of the last 5 years after a remarkable jump in both harvest and escapement totals for the Central Valley in 2019. The 2019 population likely reflected better conditions resulting from two historically wet years in 2017 and 2019, while the 2020 population is likely the result of recent dry conditions in the Central Valley. In California, the PFMC report focuses primarily on fall-run Chinook salmon in the Sacramento River Basin, as this population contributes the majority of fish caught in the ocean fishery. The metric used to represent this abundance is the Sacramento Index (SI), which is the total number of adult fish (ages 3–5) projected to be available in the ocean that will either be harvested or will escape to spawn in natural areas and hatcheries in the Central Valley. The preseason forecast for 2020 was an expected SI of 473,183 fish, with a total projected spawning escapement (to both hatcheries and natural areas) of 233,174 fish, based on fishing regulations and quotas. These were both among the highest forecasts in recent years.

 

PFMC reported that the 2020 salmon season fell short of expectations with an actual SI of 351,925 fish. This is a 30% decline from the 2019 population, but is still higher than then the previous five-year average of 264,500 fish. In 2020, an estimated 137,907 fall-run Chinook salmon “escaped” the harvest and spawned in hatcheries and natural areas of the Sacramento River Basin, which is above the long-term management goal of 122,000 hatchery and natural area spawners, but 41% lower than the preseason forecast (Figure 2). Based on average escapement from 2018–2020 (133,549), the previously “overfished” stock is now considered rebuilt because it exceeds the PFMC escapement goal of 122,000 hatchery and natural area adults. Natural area spawners (100,064) outnumbered hatchery returns (37,843), which is common in most years, but is sometimes reversed in low-escapement years such as 2017 (Figure 3). However, it is likely that straying hatchery-origin fish also comprise a large percentage of the natural-area spawners.

 

The salmon returning in 2020 were likely influenced by relatively poor outmigration conditions in 2018, when the majority of returning fish outmigrated to the ocean. This was especially true in the San Joaquin Basin, where cumulative survival from the upper San Joaquin River to the Golden Gate Bridge was only 0.5 percent (Hause 2020, San Joaquin River Restoration Program science meeting). This poor survival likely contributed to the alarmingly low number of adult returns to the San Joaquin River Basin, which experienced the lowest escapement total since the fishery collapse of 2009. In 2020, only 1,853 fall-run Chinook salmon returned to natural areas of the San Joaquin Basin and 3,628 salmon returned to Mokelumne and Merced River hatcheries, representing just 3% of the total fall-run escapement to the Central Valley. The total San Joaquin Basin escapement of 5,481 fish declined by 71% from the previous year (27,212), which was the second highest recorded escapement since 2002, and contributed 12% to the total fall-run escapement in the Central Valley. Although the San Joaquin Basin has historically constituted less than 10% of the total Central Valley escapement, its contribution has exceeded 10% every year since 2014, with an average contribution of 15%. It is not clear why the proportion of escapement has been relatively high in the San Joaquin Basin over the past few years, but it may be in part influenced by an increase in off-site hatchery releases during the drought.

 

The commercial fishery harvest in 2020 declined from the previous year, but represented an improvement from the historically low numbers seen from 2015–2018. Landings revenues (coastwide exvessel value, or price received at the dock) totaled $14.4 million, which was a decline of nearly 20% from the prior year’s value of $17.4 million, but nearly 60% higher than the previous five-year average of $9.1 million (Figure 4). However, the California fishery continues to pale in comparison to historical landings, with 2020 revenues still 60% below the 1979-1990 inflation-adjusted average of $36 million (which include coho landings during that period).