Mapping and monitoring options: Coral bleaching impact
What severity of bleaching do you wish to map or monitor?
Bleaching severity is defined as follows (Marshall and Schuttenberg, 2006):
Severe (to extreme) coral bleaching: 51-90 (to 100)% of colonies bleached. Bleaching very frequent and conspicuous, most (or all) corals are bleached.
Moderate coral bleaching: 11-50% of colonies bleached. Bleached colonies frequent but account for less than half of all colonies.
Low level bleaching: 1-10% of colonies bleached. Bleached colonies seen occasionally and are conspicuous, but the vast majority of colonies not bleached.
No bleaching: <1% of colonies bleached. No bleaching observed, or only very occasional, scattered bleached colonies (one or two observed per dive).
Reference:
Marshall, P. and Schuttenberg, H. (Eds) (2006) A Reef Manager's Guide to Coral Bleaching, Great Barrier Reef Marine Park Authority http://www.coris.noaa.gov/activities/reef_managers_guide/