February 26, 2016

Global Coral Reef Bleaching Event Update

By Dr. Gregor Hodgson, Reef Check Executive Director
Photos: Reef Check France


The 3rd Global Bleaching Event is now working its way through the southern hemisphere with NOAA Coral Reef Watch showing “hotspots” in the Central and SW Pacific and the Indian Ocean from Indonesia over to Madagascar. Significant bleaching has been recorded by Reef Check teams in many areas including Fiji and New Caledonia in the Pacific, and Mayotte in the Indian Ocean. Sadly, Fiji was just hit by perhaps the most powerful cyclone in history, killing dozens of people. The strong wind and waves mixed the waters there, rapidly reducing surface temperatures so that the bleaching and fish kills stopped.

The 3-year El Niño is now the longest in history, and is now dissipating according to NOAA, to be followed by La Niña.

But so much heat has been built up in the ocean, hot water could continue to be a problem for corals into 2017. We are asking all Reef Check teams in affected areas to get in the water and track impacts so that we can assess the damage. The good news from the field is that compared to dire predictions in 2015, it appears that the corals that survived the previous two global bleaching events are now somewhat more resistant to hot water. The microscopic algae called zooxanthellae that live inside coral tissues reproduce very quickly allowing them to adapt even faster than the corals. This means that there is still time to save coral reefs by reducing our own personal carbon footprints. Eating one less hamburger a week is one of the easiest and most healthy solutions.