Bleaching and Crown of Thorns Wreak Havoc on Maldives Reefs

By Biosphere Expeditions

Biosphere Expeditions reflects on the status of Maldives reefs following this year's EcoExpedition. 2017 expedition dates have just been announced- visit http://biosphere-expeditions.org/maldives for details.

Both coral bleaching (where hot water stresses and may eventually kill corals) and Crown of Thorns starfish can be considered 'natural' events. But when these events happen often and with increased severity, reef survival is threatened, and therefore the very survival of coral reef nations such as the Maldives.

Recent dive surveys by an international and Maldivian team of divers from Biosphere Expeditions, the Marine Conservation Society and Maldivian partners have revealed a worrying reduction in the amount of live coral in the Maldives over the past year. Healthy coral cover has been reduced to below 10% in more sheltered inner atoll reefs by the recent El Niño that has also devastated much of the Great Barrier Reef. El Niño hit the Maldives in May this year with two weeks of 32 degrees centigrade waters – at least 2 degrees above the 'normal' upper limit of 30 degrees. Outer reefs that are flushed with deeper, cooler water on a more regular basis have fared better (with an average of 25% live coral cover).

Dr. Jean-Luc Solandt, Biosphere Expeditions' programme scientist from the Marine Conservation Society says: “Our surveys showed a clear pattern, with reefs inside atolls being the worst affected. Some of the reefs denuded by the warming have also been hit hard by Crown of Thorns starfish, which eat corals. Sadly, one of the reefs that was beautiful with more than 70% hard coral some four years ago have its remnant corals now being eaten by Crown of Thorns starfish. These coral-eating starfish have decimated the Great Barrier Reef through geological time, and have been affecting the Maldives for over two years now.”

Shaha Hashim, a Maldivian conservationist and linchpin for community-based survey and reef conservation efforts, also took part in the expedition and adds: “More stringent efforts to conserve and build up the resilience of these marine ecosystems are crucial for our survival as an island nation. Development planning and policies need to put a higher value on environmental impacts, which is the prerequisite for any social or economic harmony.”

Dr. Matthias Hammer, founder and executive director of Biosphere Expeditions, concludes: “We are very concerned for the people of the Maldives. Almost everything depends on healthy reefs: the economy, food, welfare, and tourism income. If reefs are threatened, so is the very existence of the country and its social cohesion. We hope the reefs will recover, and whilst coral bleaching cannot be locally managed, fisheries, litter and pollution can be. We urge the government to use some of the income from the heavily consumptive tourism industry to pay back – to invest in the very survival of their islands and nation. Without investment from this sector, we believe the reefs will struggle to return.”

But there is a silver lining too: “What gives us hope is that the last big bleaching event in 1998 was hotter, longer and more severe, and many reefs recovered good coral growth within seven years”, says Solandt. Hammer adds: “It is not all doom and gloom. Where officialdom is failing, civil society and committed Maldivians are thankfully stepping in. Ever since Biosphere Expeditions started running its annual research trip to the Maldives in 2011, it has educated and trained Maldivians in reef survey techniques as part of the Biosphere Expeditions' placement programme. This culminated in the first-ever all-Maldivian reef survey in November 2014 and other community-based conservation initiatives since then, the latest in March 2016. Shaha Hashim, for example, has taken part in several expeditions and is now training her compatriots in reef survey techniques and setting up community-based conservation programmes. So there is hope yet!”