Abstract
The seascape mosaic formed by Biscayne Bay and the adjacent Florida Reef Tract supports a diverse shark community, including multiple life history stages of multiple species. Ontogenetic shifts—age-related changes in traits and resource use—are widespread among marine taxa and are commonly reported to drive juvenile sharks to exploit sheltered, productive inshore habitats like Biscayne Bay as nurseries to promote growth and survival to maturity. Yet despite decades of academic discourse, persistent ambiguity in how nurseries should be identified and managed across ecological and socioeconomic contexts has limited the concept’s translation into planning and rulemaking. Reviewing and synthesizing twenty-five years of nursery discourse, this dissertation first develops a decision tree that operationalizes precautionary and adaptive tiering of nursery management options across diverse data, urgency, and management capacity scenarios. Recognizing that precautionary management must be iteratively refined with fine-scale ecological data, the remaining studies reconstruct the trophodynamics of several species of South Florida’s coastal sharks using diverse and complementary methods including multi-tracer stable isotope analysis and DNA metabarcoding. As a whole, this dissertation provides managers with a framework and empirical foundations for designing ecosystem-based interventions that target the habitat and prey requirements of anthropogenically threatened shark species across ontogeny.