🔗 Share this article A Pair of Essential Florida Coral Species Declared 'Functionally Extinct' After Severe Ocean Heatwave Researchers have found that two of the most important coral species comprising Florida's reef are now ecologically extinct after a intense ocean heatwave led to devastating losses. The Meaning Behind 'Functional Extinction' Signifies The almost complete decline of these corals, which once served as the backbone of reefs in Florida and the Caribbean, indicates they can no longer fulfill their once vital role in constructing and maintaining reef ecosystems that support a diversity of marine life. Ecological extinction is a stage before total extinction, a threat that now hangs for many coral species. Scientists this month warned that a tipping point had been reached, meaning corals around the world are set to be eradicated due to climate change, which is raising ocean temperatures to intolerable levels. Researcher Perspective "We're running out of time," stated the lead author of the new Florida study. "Severe marine heatwaves are becoming more frequent and intense due to global warming, and without swift, decisive measures to slow ocean warming and boost coral resilience, we face the danger of the disappearance of even more corals from reefs in Florida and around the world." The Recent Study The recent study, featured in the journal Science, analyzed the fate of staghorn coral and elkhorn coral corals off the Florida coast after a intense marine heatwave in 2023. This event raised temperatures on Florida's fraying coral reefs to their peak temperatures in more than a century and a half. The two species are intricate, reef-forming corals and are identified because they look like, in turn, the horns of stags and elk. However, scientists who conducted underwater surveys of more than 52,000 colonies of the species, across 391 sites along Florida's coast, found widespread, often catastrophic, losses. Regional Effects Along the Florida Keys, mortality rates hit ninety-eight percent and even 100%, showing a total eradication of the corals. In southeastern Florida, where temperatures have been cooler, death rates were reduced, at about thirty-eight percent. Historical and Present Threats The two Acropora species had already endured from many years of regional pressures in Florida, such as contaminated water from contaminants that run off the land, as well as illness. But the 2023 marine heatwave has been lethal for these heat-sensitive species. The 2023 heat event caused the ninth occurrence of coral bleaching on the Florida reef – a process whereby corals become heat-stressed and expel the symbiotic algae living in their tissues, causing them to become bleached white. If temperatures remain elevated, the corals die off completely. Worldwide Consequences Worldwide, coral reefs are among the ecosystems most vulnerable to the anthropogenic climate emergency. This presents a significant danger to: A quarter of all ocean life that relies upon what are essentially the marine rainforests. Millions of people who rely on corals to sustain fish that they can consume and earn a livelihood from. Corals also serve as a protective barrier to protect our shorelines from powerful storms, which are themselves being worsened by rising global temperatures. Preservation Attempts In a desperate attempt to avert a decline of endangered corals, scientists have created repositories of Acropora in marine facilities and ocean-based nurseries. Efforts have been made to reseed corals on reefs in Florida, as well, in an effort to regain some of the 90% of coral cover lost off the state in the past four decades. But as global heating continues to intensify, there is slim chance of long-term survival of these species absent significant actions, researchers warn. Further Expert Commentary "Elkhorn corals, in particular, are some of the key wave-breaking coral species in the region," noted Andrew Baker, a ocean scientist at the Miami University. "They were once common on shallow reef crests in the Caribbean, and if we want our reefs to continue protecting our coastlines from inundation during storms, its worth taking exceptional steps to ensure we don't lose these corals completely."