The global coverage of coral reefs has halved since 1950, a scenario caused by global warming, overfishing, pollution and destruction of natural habitats, revealed an analysis released this Friday.
From the Great Barrier Reef in Australia to the Saya de Malha Bank in the Indian Ocean, coral reefs and the diversity of fish species they support are in sharp decline, a trend that is expected to increase as the planet continues to warm up, the report, published in One Earth and quoted by Guardian.
In the study – which contains data collected from 87 countries – experts found that the total coverage of reefs had halved and the diversity of species in these locations decreased by more than 60%.
Coral reefs are a vital source of food for millions of people around the world, especially for the indigenous communities from areas where fish are the main source of animal protein.
Study leader Tyler Eddy, a scientist at Memorial University of Newfoundland, Canada, was surprised by the extent of the scale of the global decline in coral reefs. “Coral reefs are among the most sensitive ecosystems on the planet, being the first to experience the effects of climate change,” he said.
“If we look at trends in coral reef cover at the country level, we find that some of the biggest declines are occurring in Papua New Guinea, Jamaica and Belize,” he continued.
The team also noted that the species composition on reefs was changing in some areas, with more resistant fish species becoming dominant.
John Bruno, a marine ecologist at the University of North Carolina and a co-author of the study, said that despite regional differences, the global health of reefs continues to decline.
“We continue to lose corals in most of the world’s reefs,” he said. The rapid intensification of marine heat waves has led to “more frequent and severe bleaching, including in some of the most isolated coral reefs in the world”, he stressed.
In the Caribbean, a recent study revealed that reefs are shrinking by about 0.25% a year. “In recent years, Caribbean reefs have been hit by hurricanes and new diseases, both linked to the warming of the oceans”, added Bruno.