Late April and early May 20-mm Surveys provide an excellent picture of the status of Delta smelt population in the estuary. Since 2017, some surveys collected no Delta smelt (Figures 1-3) in the San Francisco Bay-Delta estuary. The 2018 and 2019 survey catches (Figures 1 and 2) are a new low for Delta smelt, lower even than the 2017 survey catch (Figure 3), and the lowest in the 1995-2019 survey period.

The outlook for the Delta smelt population remains grim after these lows. Despite good conditions in spring 2018 and 2019, the severely depressed number of adult spawners indicates a continuing weak potential for recovery.

Figure 1. Catch and lengths of Delta collected in the 20-mm Survey in spring 2019. None were collected in survey 3.

Figure 2. Catch and lengths of Delta collected in the 20-mm Survey in spring 2018. None were collected in surveys 4 and 5.

Figure 3. Catch and lengths of Delta smelt collected in the 20-mm Survey in spring 2017.