Two Florida coral species declared 'functionally extinct'

In Florida, two key coral species responsible for building coral reefs have been killed off because of extreme ocean heat, a new study found.

Since the Ice Age, elkhorn and staghorn corals off Florida’s southern coast have been stacking their skeletons into elaborate, branching homes for parrotfish, eels and octopuses.

“They’ve been the most important reef builders on these reefs for 10,000 years,” said Ross Cunning, a coral biologist with Chicago’s Shedd Aquarium.

But researchers are using stark, new language to describe the status of the two species in Florida: functionally extinct.

“The numbers of individuals of these species that remain are now so low that they cannot perform their ecological functions in any meaningful way,” Cunning said. “This is the functional extinction of two incredibly important ecosystem engineers for coral reefs in Florida.”

Cunning and a team of 46 other researchers published a grim study in the journal Science on Thursday that assesses the damage caused by a historic 2023 marine heat wave in Florida. The findings are essentially an announcement that the two coral species have disappeared there because of extreme ocean temperatures.