Kanive, Paul E.Rotella, Jay J.Chapple, Taylor K.Anderson, Scot D.White, Timothy D.Block, Barbara A.Jorgensen, Salvador J.2022-08-292022-08-292021-05Kanive, P. E., Rotella, J. J., Chapple, T. K., Anderson, S. D., White, T. D., Block, B. A., & Jorgensen, S. J. (2021). Estimates of regional annual abundance and population growth rates of white sharks off central California. Biological Conservation, 257, 109104.0006-3207https://scholarworks.montana.edu/handle/1/17009Determining population trends is critical for evaluating management actions and prioritizing species protections. In this study, we used empirical data to produce an estimate of the population trend for sub-adult and adult white sharks in central California. We used the unique dorsal fin morphology to build a mark-recapture data set in a modified Jolly-Seber model (POPAN formulation) to estimate annual abundance and then investigate population growth rates using parametric bootstrapping methods for sub-adult and adult sharks (males and females). For all demographic groups combined, we found equivocal evidence for a positive regional population growth (λ = 1.07 (95% CI = 0.91 to 1.23)). However, sex- and size-specific population growth rate estimates provided some evidence of population increases for reproductively mature males (λ = 1.06 (95% CI = 0.99 to 1.13)) and females (λ = 1.06 (95% CI = 0.95 to 1.17)). For sub-adult male and female white sharks, point estimates of λ were positive but uncertainty prevents strong inference (λ = 1.07 (95% CI = 0.85 to 1.29)) and (λ = 1.08 (95% CI = 0.88 to 1.28)), respectively. Our findings of a potential increase in reproductive-aged white sharks in central California may be a result of regional fluxes in density or attributed in part to current protection efforts and subsequent increase in abundance of pinnipeds as well as reduced gill-net fisheries mortality of juveniles. A trend estimate for the entire northeastern Pacific will require obtaining similar data across known aggregation areas along the west coast of North America.en-UScc-byhttps://creativecommons.org/licenses/by/4.0/Article