August M
Across the Caribbean, a once-spectacular underwater world is giving way to stark white skeletons
A new scientific assessment released by the Global Coral Reef Monitoring Network reveals that hard coral cover in the region has fallen by nearly half since 1980, with recent heatwaves inflicting unprecedented damage.
Researchers told the Guardian that the past two years delivered the worst thermal stress ever documented on Caribbean reefs.
Heat stress and bleaching
The study traces a 48% decline in hard coral to rising ocean temperatures, which destabilise the microalgae corals rely on for food.
When heat makes those algae toxic, corals eject them, losing both their colour and nourishment.
Dr Jérémy Wicquart, one of the report’s editors, said 2023–24 produced a 16.9% drop in coral cover alone.
After a conference in Puerto Morelos, Mexico, he dived expecting the vivid reefs described in older surveys. Instead, he found that ‘all the corals were bleached. All white corals. I was very affected by that.’ Storms compound the stress, breaking weakened corals into rubble, The Guardian notes.
Economic and ecological fallout
Coral reefs occupy less than 1% of the ocean floor yet support a quarter of marine species, from turtles and sharks to queen conchs and parrotfish.
In the Caribbean, they generate about $6.2bn annually in fisheries and tourism — the latter accounting for roughly 10% of regional GDP.
But as coral declines, macroalgae is surging. With fewer natural competitors and fewer herbivores due to overfishing, macroalgae cover has climbed 85% since 1980, The Guardian reports
Signs of resilience
According to The Guardian, despite alarming losses, researchers also documented pockets of hope. In the southern Gulf of Mexico, where heat stress has been intense, scientists found robust, disease-free colonies — including critically endangered species
Those discoveries led the Mexican government to establish a new marine protected area linking two existing parks into a continuous conservation corridor.
Human proximity and responsibility
The Caribbean’s reefs sit beside densely populated coasts; the number of people living within 20km of reefs has risen nearly 28% since 2000.
That proximity increases local harm — wastewater, tourism, fishing — but also strengthens the potential for community-driven recovery.
Sources: The Guardian.
