Conservationists call for action to combat coral bleaching in Indian Ocean

A healthy coral reef. When there is a rise in sea temperatures or adverse weather events, they bleach. [Courtesy]

Conservation bodies have called for urgent interventions to combat coral bleaching in the West Indian Ocean.

The organisations, including Cordio East Africa, Arizona State University, the International Union for Conservation and Nature, and the MSC Foundation, raised concerns that the coral reef bleaching events have been observed across 53 countries and territories, including those along the Kenyan Coast.

Coral reef bleaching events have been observed in regions including the Great Barrier Reef and the Western Indian Ocean.

The western Indian Ocean region comprises the Eastern African coastal states of Kenya, Mozambique, Somalia, South Africa, and Tanzania and the island states of Comoros, Madagascar, Mauritius and Seychelles.

"Through our assessment activities, we are learning that the situation for coral survival is increasingly dire. We don't know if or how corals and ecosystems may be able to adapt to major oceanographic changes. However, we do know that as a global community, we need to act quickly to address climate change," said Beth Polidoro, Deputy Director of the ASU Center for Biodiversity Outcomes.

The conservationists said coral reefs face unprecedented threats from climate change, overfishing, and pollution.

The organisations have partnered to look into comprehensive conservation and restoration efforts for threatened coral ecosystems across the globe by employing methodologies and fostering global cooperation in coral conservation.

"IUCN recognises the critical importance of coral reefs in maintaining marine biodiversity and supporting the livelihoods of millions worldwide," says Susanne Pedersen, Director of the IUCN Centre for Science and Data Centre.

"Corals are not only one of the most biodiverse marine ecosystems, but they also provide high benefits for people, in terms of fisheries, tourism, and coastal protection," Pedersen added.

The organisations are utilising global standards for evaluating species extinction and ecosystem collapse.

David Obura, Founding Director of Cordio East Africa, said that coral reefs are critical for coastal economies and livelihoods for tropical countries.

"Providing the latest updates on their ecosystem status and extinction risk of corals is critical to inform management and policy from local to global levels," he said.

A 2021 assessment of the coral reefs in the Western Indian Ocean revealed that reefs within the East African coast from South Africa to Kenya, were classified as 'Vulnerable' to collapse. The research showed that overfishing altered the ecology of reefs and promoted algal takeover, a practice considered the greatest overall threat in African countries.

Rising sea temperatures due to climate change have also been documented as a threat to all coral reefs of the Western Indian Ocean.

Coral reefs in island nations in the Western Indian Ocean are facing a high threat. Research indicates that in four of the sub-regions (East and South Madagascar, Comoros, and the Mascarene Islands), reefs were assessed as 'critically endangered' according to the IUCN Red List of Ecosystems criteria.

Rising seawater temperatures due to climate change were identified as the greatest threat to coral reefs in these island nations.