Not too late to save coral reefs, say scientists studying coral bleaching

Study identifies pockets of resilient coral in the Indo-Pacific for conservation


A study that looked at the coral abundance of more than 2500 reefs across 44 countries in the Indian and Pacific Oceans has found that the majority of reefs have coral communities that survived in spite of severe heat waves over the last few years.

These reefs, the study says, should be targeted for protection and reef management measures. The implication, however, is that many coastal communities living near these reefs will need to find alternative livelihoods.

Published in the journal Nature Ecology and Evolution, the paper is the result of an effort by more than 80 marine scientists to study the biodiverse Indo-Pacific coral reefs in the aftermath of the world's longest and most intense bleaching event, that took place between 2014-2017, where more than 75 per cent of global reefs faced bleaching-level heat stress according to the US National Oceanic and Atmospheric Administration.

Led by scientists from the Wildlife Conservation Society (WCS), the authors found nearly 450 reefs in 22 countries across Indo-Pacific in climate 'cool' spots which, according to them, should be immediately prioritized for the implementation of protective measures like marine protected areas.

“The good news is that functioning coral reefs still exist, and our study shows that it is not too late to save them,” said Dr. Emily Darling, lead author of the study and head of WCS’s global coral reef monitoring program.

Having evaluated the impact of a wide spectrum of 21 stressors both human and climate-induced, the study points to what it would take to keep reef systems healthy. They propose a three-pronged strategy: protect-recover-transform.

The protect approach has the goal of “maintain[ing] reefs above functioning thresholds, while anticipating the impacts of future bleaching events.”

The recover approach has the goal of recovering reefs that were exposed to bleaching stress, while the transform approach aims to change the way reefs are managed in regions where significant bleaching has taken place, assisting “societies to transform away from reef-dependent livelihoods” if needed.

Positing the strategies of protect-recover-transform as being essential to respond to the varying needs of different reefs, the authors point to how local action needs to be complemented by global efforts to reduce carbon emissions and mitigate climate change to protect the remaining coral reefs.

“While coral reef sustainability depends largely on reducing carbon emissions, identifying reefs that are likely to respond — or importantly, not respond — to local management is critical to targeting development and management strategies to build the well-being of the millions of people dependent on coral reefs across the globe” said one of the co-authors, Dr Georgina Gurney, from the Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Australia.

The strategy to protect is pivoted to the 17.4 per cent of coral reefs which occurred in climate 'cool spots' during the heat stress of the 2014-2017 El Niño. Spread over 22 countries from East Africa to South East Asia, the Coral Triangle and the Pacific, the authors point to the need for international synergy in coral reef conservation measures to protect them.

The strategy of recovery is geared towards implementing measures to aid recovery of the 54.4 per cent of the reefs studied which were impacted by the 2014-2017 bleaching. The third strategy to 'transform' recognizes that the livelihoods of coastal communities dependent on the 28.2 per cent of the analyzed reefs that have become non-functional stand affected and that that needs to be transformed through other viable alternatives.

“Our findings suggest there is still time for the strategic conservation and management of the world’s last functioning coral reefs, providing some hope for global coral reef ecosystems and the millions of people who depend on them” the authors point out.