This Scientific Breakthrough Could Jumpstart the Revival of the Great American Barrier Reef

The Florida Aquarium has successfully reproduced rigid cactus coral, a first. (Photo: Snapshot from video)

The first time I donned a snorkel and dipped my head below the waves to explore a coral reef, I was 8 years old. I remember thinking that magic really did exist. Here was a whole new bobbing, technicolor world hidden under the blue Florida sea. For anyone who has experienced that first-hand, the idea that we've lost 50% of the world's coral reefs already (with another 40% likely to disappear in the next 30 years) is heartbreaking.

"We are losing coral species faster than we can learn about them," Keri O'Neil, senior coral scientist at the Florida Aquarium, told CNN.

But there is some hope. Coral researchers have been working hard to learn more about how coral functions — especially how it reproduces — to help save it. Recently scientists turned their focus to ridged cactus corals, a species pulled from the reef in 2014 by the Florida Fish and Wildlife Conservation Commission and NOAA Fisheries when it was threatened by disease. The Florida Reef, or Great American Barrier Reef as it's also known, runs just a few miles offshore from Florida Keys, and it's the third largest coral barrier reef system in the world.

After stabilizing the corals and ensuring they were disease-free, scientists started closely studying these coral in the lab, hoping to figure out how to breed them so that one day they might be returned to the reef.

But first, coral sex basics

Sponges, Sea Fans and Sea Rods make up a coral composition. Picture taken in Broward County Florida.
A coral reef in Florida shows the amazing diversity of a coral community. Pictured here are sponges, sea fans and sea rods. (Photo: Peter Leahy/Shutterstock)

Initially, the researchers didn't even know how this species of coral multiplied. Coral have a huge variety of ways they can reproduce, including parthenogenesis, where coral embryos grow from adults without fertilization; budding (like what a cactus or succulent plant does); spawning, where eggs and sperm are released into the water column and join there to make an embryo, and more.

For many species of coral, including the ridged cactus, the type of reproduction is simply unknown. The scientists didn't know whether they'd be able to capture reproduction-in-action once the coral was outside its normal ecosystem.

But after the ridged cactus corals had settled into their new home, they did indeed start having sex in their particular way. Turns out that ridged coral release sperm into the water, and some of it is then caught by nearby eggs within coral bodies. This is called brooding, because once the egg is fertilized, the larvae develops inside the parent coral.

When the time is right, the larvae is expelled or birthed into the water, where it swims around until it finds just the right place to settle down for life, a process you can watch in the video above.

The breakthrough

rigid cactus coral larvae
The pinkish-white larvae seen floating in this photograph is looking for a place to call home. (Photo: Snapshot from video)

At the Florida Aquarium, this was seen as a huge coup for understanding how these coral reproduced, opening up a new way to preserve and protect them.

"This breakthrough is just really exciting; we're still learning basic new things you'd think we've known for hundreds of years. It's just people never worked with this species before and now that we have the opportunity to work with these corals in the lab, we're going to find out so much more about them," Roger Germann, Florida Aquarium president and CEO, told CNN.

Getting these corals to reproduce, and understanding more about their life cycle is just the latest triumph for the aquarium. Last year it became the first in the world to get another Atlantic coral — pillar coral — to spawn by using using advanced LED technology in what they call a "coral greenhouse."

This isn't just good news for coral, which has been decimated the world over by bleaching events caused by climate change, as well as disease outbreaks that harm already weak corals. It's good for people too: "Just think, a solution to the next pandemic or human illness could be discovered from healthy coral reef," Germann said.