Coral bleaching and elevated sea-water temperature in Milne Bay Province, Papua New Guinea, 1996

Abstract

A coral bleaching event began in February 1996 on reefs in Milne Bay Province, Papua New Guinea. Corals were affected on the shallow fringing reef and to water depths of greater than 20 m on the reef slope. Bleaching was extensive and in the survey area 54% of all corals were bleached. Branching corals (particularly Acropora and Pocillopora) were more severely affected than massive species. Bleaching occurred at the time of the annual maximum monthly sea temperature when long-term sea temperature data sets recorded an anomaly of + 1.29°C. Analysis of the anomalies over the previous 40 years shows a positive trend of 0.09°C per decade.