Disease-Associated Effects on Reproductive Output of Chesapeake Bay Striped Bass

A thorough reproductive study on the Chesapeake Bay Striped Bass, an economically and ecologically vital population, has not been conducted since the early 1990s, just after the stock had crashed but before it rebounded. Due to management efforts, the population has grown tremendously, necessitating an update to fecundity and maturity schedules. Additionally, prevalence of mycobacteriosis in Chesapeake Bay Striped Bass is greater than 50%, which raises questions about population level effects of the disease. The objectives of this study are to update current knowledge on maturation and fecundity of Striped Bass in the bay and examine disease-associated effects of mycobacteriosis on reproductive metrics through egg-per-recruit analysis. Reproductive data were obtained from female Striped Bass collected (n=469) during spring 2012-2013 in the York, James, and Rappahannock Rivers of the Chesapeake Bay. Fish ranged in age from 2-17 years and disease prevalence across rivers and years was 64%, with prevalence increasing with age to age-7 and then decreasing in the older fish. Model results indicate total lifetime egg production of disease-positive fish is substantially reduced, which has important implications for management.