The exploitation of reef fishes, such as black sea bass off the southeastern U.S., has increased dramatically since the 1970s leading to concerns over population size. The primary method of determining reef fish population status is through stock assessments, which mathematically model temporal changes of fishing mortality, fish abundance, and spawning stock biomass. A complementary method of tracking stock status is the evaluation of a population’s genetic diversity. Studies indicate that reductions in population size of fish species diminish genetic diversity, impacting a stock’s long-term sustainability and ability to recover from overfishing. By tracking temporal changes in effective population sizes and other measures of genetic diversity, it is possible to generate population data that can independently corroborate trends seen in a traditional stock assessment. Black sea bass are an excellent opportunity to explore patterns of genetic changes associated in overfished populations because information is available on their genetic structure and life history patterns along the U.S. East Coast.
This study will exam the genetic diversity of black sea bass stocks before, during, and after periods of overexploitation to further understanding of the effects of fishing on the health and recovery of these stocks and also their ability to adapt to environmental change. Researchers will quantify genetic diversity parameters in historic and contemporary populations of black sea bass using DNA samples from the S.C. Department of Natural Resources’ collection of fish otolith bones to determine changes over time. Additionally, researchers will test if temporal patterns of genetic diversity are related to changes in population abundance. The resulting project data will provide an additional indicator of the status of these species in terms of quantitative patterns of genetic diversity relative to more traditional stock assessments.