Proceedings of the 9th International Coral Reef Symposium, Bali
1999 – 2001
Cumming, R.L., Carlson, B.A., Hughes, A., Koven, J.F., Lovell, E.R., Quinn, N.J., Sykes, H.R., Taylor, O.J.S., Tosacno, M.A., Vaughan, D.
The south-western Pacific island countries were largely unaffected by mass coral bleaching during the intense El Nino of 1998, but experienced mass bleaching in 2000 during the subsequent strong La Niña. Nineteen reef locations were surveyed in eight geographic regions within the Fiji archipelago between mid April and early July 2000, to assess the geographic extent and intensity of Fiji’s first recorded mass bleaching event. 64% of all scleractinian coral colonies surveyed were bleached (partially or fully, or recently dead from bleaching), and mass bleaching occurred in all regions surveyed except in the far north (north of Vanua Levu).
Bleaching was most intense (>80% of colonies bleached) in southern and eastern sites (south and east from Viti Levu and Vanua Levu, Kadavu and Northern Lau), and lower in some western and one northern site(s). The geographic patterns in bleaching coincide with Fiji’s position on the north-western edge of an area of high sea surface temperatures (SSTs), and support the prediction based on SSTs that bleaching should be most severe in the south and east. Seawater temperatures exceeded expected summertime maxima for 5 months and peaked at 30-30.5oC between early March and early April 2000. The bleaching threshold for Fiji appears to be in the range of 29.5-30oC. Our data estimate 10-40% of coral colonies had died from bleaching within four months of the onset of bleaching.