Linking Juvenile Habitat to Adult Stock Dynamics of the Black Sea Bass (Centropristis striata)

Degradation of coastal systems has threatened juvenile habitat availability and may impact the stability of fish populations. However, it is unknown how specific nursery habitats influence post-juvenile life history (e.g., sexual succession) and resulting stock structure and production. Our research utilizes otolith elemental analysis to quantify the function of estuarine and offshore juvenile habitats as a source contributing to the spawning, adult population. Furthermore, we introduce a demographic modeling approach to the management of black sea bass (Centropristis striata) using nursery-specific variables. Elemental analysis of juvenile otoliths from both estuarine and open-coast habitats from the years 2009-2014 indicates significant differences in habitat signatures between putative nursery alternatives. Using discriminant function analysis, we correctly identified 95% of all juveniles to the habitat where they were captured. Signatures from hundreds of adult fish otoliths are being analyzed to determine the proportional contributions of estuarine versus offshore habitats in maintaining black sea bass stock. Between-nursery comparisons of adult growth rates and proportion of males at age will also help to identify the presence of any carry-over effects resulting from juvenile habitat. Finally, this data will be used to explore the applicability of stage-based population matrices for the assessment of black sea bass.