How do we find Super Reefs?
Coral Reefs don't talk, and we can’t be everywhere at once during an El Nino to witness how each coral reef responds to ocean warming. So, we had to figure out a way to get reefs to tell their story.
That story is contained within the skeletons of big, old corals. When the reef bleaches in response to warming, the corals record the event in their skeletons.
We first take a sample of the coral, similar to a "biopsy," called a skeletal core. In fact, we take many cores over a wide area. Then we ship the cores back to Woods Hole, where we image them using a 3-D CT scanner.
If the images of many cores from one site reveal stress bands, we know the reef bleached that year.
The scans also reveal coral reefs that have no stress bands. These may be reefs that never bleached despite the occurrence of extreme warming events, possibly because local oceanographic conditions keep the reef itself cool. They also reveal coral reefs that bleach frequently but remain healthy and productive because they are able to bounce back from periodic warming. The scans also reveal coral reefs that have bleached in the past but have not done so recently, despite record high temperatures, indicating that these reefs have adapted to warming waters.
Shallow and lagoon reefs on Dongsha Atoll in the South China Sea bleached in 2015, but corals in the deeper, fore-reef community survived because they were cooled by a phenomenon known as internal waves.
Seeking Super Reefs
We are looking for all three types of Super Reefs: those that have never bleached despite high temperatures, that have a history of bleaching but remain healthy and productive, or that have bleached in the past but have not done so recently.
We have already discovered such reefs in Thailand, the South China Sea, and the Central Pacific, our search continues for more because time is running out for coral reefs worldwide.
Our goal is to establish a global network of Super Reefs across the tropics that would become repositories of healthy corals. Once carbon emissions and global temperatures have stabilized, these corals could then be used to recolonize dead reefs.
Working closely with Conservation International and the governments of coral reef nations, we need to make sure these reefs are cared for and protected. Doing so will help to ensure the survival of coral reef ecosystems..
Some super reefs are already protected, but others are not.