Dredging activity near coral reefs can increase the frequency of diseases affecting corals. researchers say after a a world-first study. 'At dredging sites, we found more than twice as much coral disease than at our control sites,' says the lead author of the study. "Corals require both light and food to survive," researchers explain. "And unfortunately, dredging impacts corals on two fronts: increased turbidity means less light for photosynthesis, while increased levels of sediment falling onto the coral can interfere with their ability to feed."...