Florida scientists use predatory bacteria to curb disease in endangered Caribbean corals

In a controlled laboratory study, scientists challenged fragments of the critically endangered staghorn coral (Acropora cervicornis) with the pathogen Vibrio coralliilyticus and subsequently applied Halobacteriovorax, a marine bacterium that preys on other bacteria. About 57% of the treated fragments displayed bleaching only at the initial infection point, indicating that the disease failed to spread further. Untreated corals exhibited widespread tissue damage and bleaching, highlighting the rapid progression of the infection.

Analysis revealed that Halobacteriovorax dramatically reduced Vibrio levels while preserving most of the coral’s beneficial microbial community. The predator did not become a permanent resident, declining after its job was done, which points to a temporary, biologically based treatment. Although promising, the researchers caution that field trials are needed to assess effectiveness under natural reef conditions. The findings open a potential new avenue for coral disease management that avoids the collateral damage of broad-spectrum antibiotics.