Program Overview
The Sturgeon Study was discontinued in 2023. Information on this web page will remain for archival purposes.
Staff of the Adult Sturgeon Study historically calculated estimates of white sturgeon abundance, relative abundance, harvest rate, and survival rate by using data from Commercial Passenger Fishing Vessels (Party Boats; CPFV), various creel surveys, and a mark-recapture program. Southern distinct population segment (sDPS) green sturgeon were also caught by the study, providing a metric of relative abundance and allowing staff to tag individuals with acoustic transmitter tags. Catch data from party boats have been collected since 1935 and the mark-recapture study operated from 1954-2022, providing long-term data on San Francisco Estuary sturgeon populations.
Sturgeon were captured for tagging from August through October by the California Department of Fish and Wildlife (CDFW) Region 3 (Bay-Delta) using drifted trammel nets (a form of modified gillnet) in Suisun Bay, Grizzly Bay, and San Pablo Bay. Captured fish were measured and tagged with an individually numbered plastic disk tag, each of which was assigned a value of $20, $50, $100, or $150. The study relied on angler returns of disk tags through the mail and via creel survey to calculate absolute abundance estimates, harvest rate, and survival rate. Tags can now be returned via email by sending a picture and catch information to r3sportfish@wildlife.ca.gov.
History
- 1954: CA Department of Fish & Wildlife begins mark-recapture (tagging) program
- 1967: Tagging program continues after long hiatus
- 1990: Slot-size length regulation implemented (i.e., no more minimum only length)
- 1998: Tag rewards set at $20, $50, & $100 to incentivize tag returns
- 2006: Green Sturgeon federally listed as threatened; harvest prohibited
- 2007: Sturgeon Fishing Report Card required of each angler sturgeon fishing in CA
- 2013: Regulation change from total length to fork length (now 40-60 inches)
- 2015: Tag rewards set at $50, $100, & $150 (see photo of disc tag below)
Relevant Reports and Related Information
Example of reward disk tag. CDFW image