Abstract
Diadema antillarum have undergone significant reductions in population size throughout the Florida Reef Tract and the Caribbean since a disease outbreak led to die-off events in 1983 and 1991 (Feehan et al., 2016). Paired with declines of stony coral populations and loss of herbivores, reduced numbers of D. antillarum have resulted in increases in macroalgal cover on coral reefs. This cascade of events has contributed to the overall decline of coral reef health in the region. This project created the foundation required for ongoing experimentation regarding captive spawning and rearing of D. antillarum. During their larval stage, D. antillarum consume microalgae. To culture these microalgae on-site, protocols for sterilization, inoculation, and scaling were developed. Small culture vessels were sterilized in an autoclave while larger carboys were sterilized with dry bleach. Salinity and pH were monitored and maintained using frequent water changes. To support health and fecundity, adult urchins were fed cultured Gracilaria algae . Spawning procedures were developed and adjusted as needed throughout the project. Spawning time, individual test diameter, and water temperature were recorded for each spawning trial. Further research will use these protocols to create strategies to spawn, rear and release D. antillarum into the wild.