Red-Band Disease - The Offline Version

Another disease that resembles black-band disease (BBD) is red-band disease (RBD), which has been reported by Laurie Richardson to affect hard corals and by Deborah Santavy to affect sea fans. Elizabeth Dinsdale has reported a "brown band" infecting corals on the Great Barrier Reef that is distinctly different from BBD.

Red-band disease on boulder brain coral, Colpophyllia natans, Mexico. Photo by S. Brooks.
Appearance	As the name indicates, the "band" is a soft microbial mat that is brick red or dark brown, not black, in color and easily dislodged from the surface of the coral tissue. This disease affects hard star and brain corals (Diploria strigosa, Montastraea annularis, Montastraea cavernosa, Porites astreoides, Siderastrea radians, Colpophyllia natans) and sea fans in the Caribbean, and star, brain, and staghorn corals on the Great Barrier Reef.
Cause	The band in RBD appears to be composed of different cyanobacteria and microorganisms than those found in BBD and the microbial mat movement is different; the types of microbes present might be different depending on the coral host, but little is known about this (Richardson, 1992; Santavy and Peters, 1997). Several scientists are studying the composition of these microbial mats to determine how they differ from the BBD mats.
Distribution	RBD is encountered only infrequently in the Caribbean. "Brown band" has been found on the Great Barrier Reef.
Impact	As in BBD, the loss of coral tissue leads to fouling of the skeleton with filamentous algae and sediment accumulations that can prohibit settlement of new corals. The entire sea fan or coral might be killed or live portions might remain if the microbial mat disappears.