Indian Ocean coral reefs are in danger of collapsing within the next 50 years, according to a new study. From Seychelles to South Africa, reef systems could face functional extinction, threatening the lives and livelihoods of marine and terrestrial animals — including humans.
Eighteen researchers, mostly working at African institutions, contributed to the study published in Nature Sustainability earlier this week. They analyzed 11 sub-regions of the western Indian Ocean, enlisting the International Union for the Conservation of Nature’s (IUCN) red list framework, just as researchers have done when examining threats to plants and animals. This time, the researchers looked at the health of reef ecosystems.
Unsurprisingly, global warming, with its rising seas and water temperatures, is having a perilous effect on reefs. Notably, corals are ejecting algae from their tissue, leading them to turn bone white. These so-called “bleaching events” are becoming increasingly common. Overfishing of top predators around the reefs hasn’t helped matters.
“The collapse of a reef means it becomes functionally extinct as a reef system,” said David Obura, the study’s leader and chair of the IUCN corals group, as reported by The Guardian. “You might still find some species there but they won’t be able to construct a reef any more. All of the services we get – coastal protection from sea-level rise, tourism, fisheries, especially for low-income households and communities – are at risk. The tourism sector is huge in east Africa and it depends on heathy reefs.”
And while it could take 50 years for the reefs to completely collapse, it could happen sooner if humans fail to contain global warming. The future really depends on how humans act in the next 10 years, Obura stressed.
Around the globe, coral reefs have shrunk by half since the 1950s. Pollution, climate change, overfishing and habitat destruction are the main factors killing reef ecosystems. Some of the most critically endangered reefs are in Madagascar, the Comoros and Mascarene Islands. (inhabitat via The Guardian)