Can Shading Drive the Transition from Black Band Disease to a Cyanobacterial Patch-like Stage in Montipora Corals?

Black band disease (BBD), which overgrows and kills scleractinian coral, is known to have various phases. The initial phase is the cyanobacterial patches (CPs) phase, followed by the intermediate phase (IP), and finally the mature BBD phase. Here, we hypothesize, pending further evidence, that when coral fragments infected with mature BBD are placed under shaded conditions, the BBD band shifts into a CP-like condition, with the shading causing a complex shift in the microbial consortium. While these microbial changes are beyond the scope of this paper, the photographs within provide interesting potential insights into this transition.