Prevalence of Vibrio coralliilyticus in stony coral Porites sp. in the Gulf of Aqaba, Jordan

The purpose of this study was to assess the health of stony coral Porites sp. based on the presence of bacterial pathogens, specifically Vibrio coralliilyticus, in the Gulf of Aqaba, and to assess the impact of anthropogenic activities on Porites sp. Porites sp. specimens were collected from the Marine Science Station (MSS) and a public beach (Yamanyeh) in Jordan. Mucus, water and sediment samples were collected throughout the year. The Vibrio-like population was higher in diseased samples than in healthy samples and was slightly higher in Yamanyeh than in MSS in all the samples. In samples from both sites, there was a seasonal variation in the Vibrio-like population, with a decline in population as the temperature reduced. All samples contained virulent isolates clustered with V. coralliilyticus strains. Inoculation of healthy Porites sp. fragments with virulent isolates and V. coralliilyticus strain caused bleaching of the coral after 48 h. Therefore, V. coralliilyticus represents a pathogenic agent which may contribute to bleaching in Porites sp. in the Gulf of Aqaba and may not be affected considerably by anthropogenic activities. This is the first report of a bacterial pathogen of corals in Jordan; future studies should identify other coral pathogens in this region.