Coral Bleaching
Bleaching is not actually a disease, but rather a colony's response to one or more stresses. Every coral species is vulnerable to Bleaching. Increases in light levels or ultraviolet light, decreases in light levels due to turbidity (cloudy water) and sedimentation (run-off from land), increased water temperatures (either seasonally or globally), increased salinity, and bacterial infection are all stresses. It is possible for a colony to recover from a bleaching episode based the health of the colony and the duration of the bleaching episode. However, if a colony has to deal with more than one stress factor at a time or the bleaching continues for an extended period of time, it will cause partial or entire colony death.