When I last updated the status of striped bass in August 2021, it did not look good.  The fall index was at its minimum (Figure 1).  In 2021 and 2022, the index remained unchanged – as expected for drought years.

With 2023 very wet and with somewhat reasonable indices in wet years 2017 and 2019, combined with the fact that stripers start reaching maturity at ages 4 to 6, might we expect some level of recovery in this fall’s index?  I think so.  The numbers of 4-to-6-year-old adult spawning stripers should be up this year.

South Delta export pump salvage of age 0 stripers was low in summer 2022 a drought year (Figure 2).  But it is much higher since the Bureau of Reclamation turned on the CVP’s Delta pumps in late June 2023 (Figure 3), even compared to 2017 (Figure 4), which had moderate indices (see Figure 1).  With the state pumps turning on in early July and exports going to a maximum 10,000+ cfs (20,000 AF/day) there are much higher striped bass age-0 salvage numbers in this wet year.  The fall striper index should indicate at least a modest recovery.

Figure 1. Striped bass Fall Midwater Trawl Survey Index (log10[index+1]) versus prior Summer Townet Index (log10). Select years labeled, with color of number showing year type: blue=wet, green=normal, and red=critically dry.

Figure 2. Striped bass salvage in spring-summer 2022.

Figure 3. Striped bass salvage in spring-summer 2023.

Figure 4. Striped bass salvage in spring-summer 2017.