In a small birth explosion, coral scientists see hope for endangered reefs.

Keri O’Neil almost missed the tiny beans expelled by the cactus coral she studies at the Florida Aquarium Conservation Center.

The tiny granules, measuring only an eighth of an inch long, were easy to miss against the colorful backdrop of gnarled ridges and folds of unusual species.

“That first day, we weren’t even sure what we were looking at,” said O’Neil, a senior coral scientist at the aquarium.

What O’Neil and his colleagues had witnessed was a furrowed cactus coral.

Scientists say it is the first time that this type of coral, which may vaguely resemble a cross between a lettuce head and a human brain, has reproduced naturally in a laboratory. Successful births offer hope for conservationists vying to save Florida’s endangered coral reefs.

“The whole purpose of this project is to rescue corals and start a land-based breeding program so that we can resupply reefs in the future,” O’Neil said.

Cactus corals are native to Florida and the Caribbean, but an outbreak of a mysterious year-old disease threatens their survival. The Florida Aquarium has partnered with the Florida Fish and Wildlife Conservation Commission and the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service to breed healthy corals in laboratory-based “greenhouses”.

Crested cactus corals are just one type that is bred in the Florida Aquarium, but it is a species that scientists are eager to study. Known as melancholic corals, these hermaphrodite specimens reproduce by releasing sperm into the water that then fertilizes the eggs within the parent corals. And unlike many other coral species, which subsequently eject hundreds or thousands of eggs at a time in what is known as mass-synchronized spawning events, breeding corals release a handful of fully developed baby larvae or corals into the weeks or even months.

“We’ve had between seven and 45 in one night, and they’re still going,” O’Neil said.

Since April 12, scientists have counted 340 larvae, and although they start life by swimming, baby corals eventually settle and go through a metamorphosis, much like caterpillars that turn into butterflies, to become the so-called polyps of coral.

Corals raised in the Florida Aquarium were collected more than a year ago, but the goal is to eventually return the specimens to their natural habitat.

Crested cactus corals have been abused by the stony coral tissue loss disease, which has left irregular white spots on specimens along the Florida Reef Tract, which stretches for about 360 miles in an arc that hugs the shoreline. southeast Florida.

Researchers aren’t sure what causes the disease, but they hope that shore-based breeding programs can help restore Florida’s devastated reefs.

Laboratory-based reproductive efforts could also benefit other threatened coral species worldwide. Rising temperatures and warming oceans threaten the Great Barrier Reef, which is experiencing its most widespread bleaching event. And a study published in February that was led by scientists at the University of Hawaii at Mānoa found that climate change could wipe out almost all coral reef habitats worldwide by 2100.

But O’Neil said successful breeding programs are giving scientists hope that conservation efforts could save endangered corals around the world, even if they sometimes happen unexpectedly, such as corals from Cactus.

“A lot of things with coral breeding are like this,” he said. “It was a fluke. Sometimes we are lucky.”