Project: Linkages Between Larvae and Recruitment of Coral Reef Fishes Along the Florida Keys Shelf: an Integrated Field and Modeling Analysis of Population Connectivity in a Complex System

Description from NSF award abstract:
This project deals with the important and timely theme of marine population connectivity. The degree to which populations of benthic marine organisms are connected via the dispersal of larval propagules is a central unanswered ecological and oceanographic question. The complex oceanography of marine systems, and high mortality and diffuse concentrations of larvae make direct measurement of larval sources generally unfeasible, particularly for marine populations distributed along open coastlines. In addition, ecological population connectivity is not only a function of the physical transport of larvae, but also the interaction of factors influencing larval growth, survival, and condition at settlement. For example, oligotrophic open-ocean environments may lead to slower larval growth, longer pelagic larval durations, and lower survivorship of larvae compared to larvae from nutrient-rich nearshore waters. Data indicate that the relative condition of larvae influences their survival on the reef and the degree to which they contribute to the population. Ultimately, as ocean currents, spawning patterns, larval survivorship, settlement, and their interactions are highly variable, the only method for examining ecological population connectivity over multiple time and space scales in oceanographically complex environments will be data-validated three dimensional biophysical models capable of assessing dispersal outcomes over a wide range of temporal and spatial variation. 

The overall goal of this study is to quantify the relative contributions of upstream (far-field) versus local (near-field) sources of reef fish larvae to the Florida Keys. The proposed study will integrate a comprehensive, three dimensional hydrodynamic model with a Lagrangian particle tracking model to connect the pathways between observed ichthyoplankton distributions and larval settlement.