Meeting Abstract
Remote locations along a species’ range edge have the potential to influence connectivity across large geographical areas and may serve as refugia from the effects of climate change. Here, we modeled source-sink dynamics for reef-building corals from one of the most isolated and high-latitude Caribbean coral reefs, the Flower Garden Banks (FGB) in the Gulf of Mexico. We experimentally determined the time courses of competency and mortality for two dominant reef-building corals (Pseudodiploria strigosa and Orbicella sp.). While mortality rates were nearly identical in these two species, their competency timing differed dramatically: P. strigosa larvae are capable of metamorphosis within 2.5 days of fertilization. In contrast, Orbicella larvae did not become competent until > 20 days post-fertilization. These biological measurements were used to parameterize a biophysical dispersal model to predict yearly particle transport between 2009 and 2012. Simulations of particle dispersal revealed that species with short (3–20 day) pelagic larval durations (PLDs), such as P. strigosa, are isolated from the rest of the Caribbean and self-recruitment is highly variable across years. Notably, species with long PLDs (20–120 days) have similar year-average probabilities of self-recruitment to the FGB but are also capable of exporting larvae to distant reefs in Florida, the southern Gulf of Mexico, Cuba and the Bahamas. Our results highlight the self-sustaining potential of FGB coral populations and the ability for FGB species with long PLDs, including endangered Orbicella species, to act as a source for adjacent Caribbean populations.
