Standard Presentation (15 mins) Australian Marine Sciences Association 2022

Environmental drivers of post-settlement mortality in seeded corals : implications for restoration of inshore reefs   (#358)

Cathie A Page 1 , Christine Giuliano 1 , Carly J Randall 1
  1. Australian Institute of Marine Science, Townsville, Queensland, Australia

Recovery of coral populations from disturbances is dependent on the successful recruitment of new individuals. Yet frequent regional-scale bleaching events are disrupting the supply of coral larvae to many reefs, while increasing macroalgal cover is limiting the available substratum for coral settlement, particularly on inshore reefs. Coral seeding may overcome some of these challenges, however knowledge of local drivers of early post-settlement coral mortality is crucial to understand methods to enhance seeding success and improve inshore reef management. Here we report the results of a 1-year deployment of engineered coral seeding devices housing multiple species on turbid inshore reefs in Woppaburra sea Country (Keppel Islands). At one-year of age, and after nine-months of deployment, we detected significant differences in survival between the three coral species settled and deployed: Acropora muricata (13%), Montipora aequituberculata (40%) and Acropora millepora (42%) and an effect of deployment orientation, with survival being higher on outward facing plugs (54%) compared with downward facing plugs (9%). Survival was also variable among reefs and sites within reefs, driven, at least in part, by variation in biological and environmental variables. We discuss the implications for these results for future restoration efforts on the inshore Great Barrier Reef.