Quantifying capture and ingestion of live feeds across three coral species

Abstract Nutrient acquisition through heterotrophy is critical for the health of reef-building corals. The optimization of exogenous nutrition protocols to support a diversity of aquaculture corals requires improved techniques to assess feeding rates. Here, we compared the feeding rates of three coral species ( Acropora millepora , Pocillopora acuta and Galaxea fascicularis ) fed Artemia salina through capture rate (indirect) and dissection (direct) approaches, with direct detection and enumeration within dissected polyps facilitated by fluorescent microbeads ingested by the Artemia . When A. millepora was provided Artemia at 3 individuals ml −1 for one hour, the calculated capture rates (0.7 ind. polyp −1 h −1 ) overestimated prey ingested compared to prey detected directly within polyps (0.2 ind. polyp −1 h −1 ), and ingestion varied significantly between genotypes. In contrast, for P. acuta, capture rate calculations (1 ind. polyp −1 h −1 ) underestimated prey detected within polyps (3.5 ind. polyp −1 h −1 ) and ingestion did not vary between genotypes. For G. fascicularis , the feeding rates were similar as calculated by both capture rates (59 ind. polyp −1 h −1 ) and by polyp dissections (75 ind. polyp −1 h −1 ). Results from this study provide valuable insights into coral feeding rates of different coral species that can improve prey enrichment and feeding strategies for nutritional supplementation of corals in captivity.