New Video: Evaluating Non-Native Fish Populations in the San Joaquin River

Large striped bass from fyke

Our newest video features our ongoing project to study the non-native fishes of the San Joaquin River in California’s Central Valley. Non-native fishes outnumber natives in the San Joaquin, but we know surprisingly little about them, such as the sizes of their populations. This video shows how we are using large, cylindrical fyke traps to catch bass and catfish for a mark-recaptures study. The species included in this study are striped bass, large and smallmouth bass, white catfish, and channel catfish.  The fish are marked with tags and released, in hopes of recapturing them again. Each time a tagged fish is recaptured, it gives us information about fish movements, and helps us estimate the size of the population.

Anglers can be part of this study by reporting tagged fish that they catch. Each tag report comes with a reward, and helps contribute to knowledge of these species. This map shows where anglers have reported tagged fish to-date, with the record distance being a striped bass caught in the Sacramento River outside of Chico, nearly 230 miles from where it was tagged! This project is funded by the Banta-Carbona, Patterson, and West Stanislaus irrigation districts, and is helping to answer some important unknowns about non-native fishes in the San Joaquin. Read more about the project here,  and never miss any of our videos by subscribing to our YouTube page.

Map of Fyke project tag recaptures