Developing appropriate methodology for assessing anti-pathogen properties of mucus-enriched water from corals

Abstract

Global coral reef health is in rapid decline. A major contributor to this trend is warming ocean temperatures. As ocean temperature increases, corals become more susceptible to diseases that lead to bleaching and tissue mortality. Vibrio coralliilyticus is one of the few documented coral bleaching pathogens. Previous studies developed methods to quantify V. coralliilyticus metabolism and developed culturing procedures to test the anti-Vibrio potency of mucus-enriched water from numerous coral species. However, the best way to collect and process mucus-enriched water from corals was not determined. Previous efforts obtained mucus-enriched water via coral fragmentation and agitation in seawater. This methodology detected anti-Vibrio activity from several species, but required destructive sampling of the corals. This prevents collecting data over multiple time points without confounding time with previous damage. This study evaluates the effectiveness of less destructive methodologies for sampling mucus-enriched coral water. This study evaluated the effectiveness of the less destructive method of slowly sucking coral mucus from colonies in the field using a syringe. Tests using this method on mucus enriched water from 9 species of coral detected no anti-pathogen activity. In contrast, tests using the fragmentation and shaking method found significant anti-pathogen activity in 3 of the 4 species tested. the less destructive method assayed here, is ineffective at assessing the anti-pathogen potential of corals.