Quantifying capture and ingestion of live feeds across three coral species

Optimal nutrition is paramount to the health of all organisms. Scleractinian coral species utilize a diverse range of feeding modalities and behaviours, and optimal heterotrophic feeding protocols may therefore vary between species. The described experiments assessed the capture and ingestion rates of the commonly used live feed organism Artemia by three Scleractinian coral species (Galaxea fascicularis, Pocillopora acuta, Acropora millepora; 3 genotypes per species). The described experiments were performed in a SeaSim aquaria-room (in the CMMG facility) using 2.5 L flow-through feeding chambers (2 L water), with water movement provided by a magnetic stirrer. For each coral species, Artemia were delivered at different densities, and results were acquired and compared using two distinct methods: the frequently reported capture rate method (an indirect method; Capture experiment), and direct quantification of Artemia preloaded with fluorescent beads in polyps after dissection (demonstrating ingestion; Ingestion experiment). This work was supported by AIMS appropriation funding for the project Coral aquaculture: nutrition, probiotics and health. The project built on previous AIMS research into coral nutrition and supported the development of RRAP-funded projects (CAD-1 Coral Propagation and Deployment and ECT3-2.2 Coral nutrition).