(a) Digitized image of coral A10 from November 2010 with impact categories in color (red: visible impact; green: no visible impact); (b) Same image recoded based on state of the coral in March 2012, with transitions between categories in color (cyan: visible impact to no visible impact; white: visible impact to colonized by hydroids; pink: no visible impact to colonized by hydroids; red and green means no change from 2010).