- [Narrator] You're watching history in the making.

This species of coral is called Orbicella Faveolata, or mountainous star coral, and it had never spawned in a lab before this moment.

Not many people get to see this phenomenon.

Let's watch that again.

[film rewinding] - [Dr. Fogarty] These corals are so amazing when they spawn because their pulse spawners, so they synchronously release their gametes in one pulse.

- [Narrator] Spawning is one way that corals reproduce.

They release gamete bundles of eggs and sperm into the ocean where they float to the surface and mix.

- You can imagine if you're looking at an entire reef and all these individual star corals are releasing at the same time, and then you're just swimming through what looks like a pink snowstorm of these gamete bundles.

It's really something to put on your bucket list.

I just remember being underwater for many nights in a row.

It's dark waiting for these corals to spawn, and finally this huge star coral that we were monitoring just erupted in coral gamete bundle.

And at that moment, I think is when like, yep, this is it.

This is what I'm going to dedicate my career to.

And 20 years later here I am, and I'm watching the same species of star coral spawn but this time in my lab here in captivity.

And it just, it's very overwhelming and humbling that that we now have the technology to do this in captivity.

- [Narrator] The ability to have corals reproduce in the lab could have huge implications, as corals around the world are being stressed by the effects of climate change and threatened by diseases like the mysterious stony coral tissue loss disease which is currently working its way through the Caribbean.

- It just quickly kills some of these corals, and we don't really know what causes it yet.

We don't know what the pathogen is.

And I have a feeling that this is gonna be kinda the straw that broke the camels back as it circulates around the Caribbean, because unlike some of the other disease, this affects over 20 corals.

And so it can devastate an entire reef, not just one or two species.

And if we lose coral reefs, I would say it's gonna affect the global economy and it's gonna affect all of us.

- [Narrator] Coral reefs play important roles in the seafood industry, shoreline protection, ecotourism, and maintaining biodiversity in the ocean, not to mention their potential to contain medical compounds that we haven't discovered yet.

- [Dr. Fogarty] Corals are in trouble, and that's worldwide, particularly in the Caribbean, but even the Great Barrier Reef has seen devastating declines.

- So that's actually what caused all these corals to come into captivity.

And it was so bad that they're like we need to start taking these and almost seed banking them, because they might all die out in the water, and so we to keep the population in captivity.

Phase two now is how can we start reproducing them?

How can we get them back out into the water?

And that's where we're starting to really jump in.

- [Narrator] Spawning corals in the lab will allow scientists to increase the genetic diversity of coral reefs.

- For the past probably 20 years, most of the restoration has been focused on asexual fragmentation, and taking a little piece of coral and then growing it out into a nursery setting, then they can outplant them to the reef.

And this is effective and it's a good way to restore, but there's no new genetic information that you're putting out on the reef.

The problem with that is that then all the different stressors that have led to coral decline are still gonna be there.

So you're out planting these corals into the same environment that killed the parents essentially.

With sexual reproduction, what we're able to do is we're able to increase the genetic diversity with the hope that certain combinations of individuals will douce babies that might be more resistant to disease or thermal stress or certain pollutants.

And then those will be the future of the reef, and that's where labs such as mine come in.

We can test these various factors on the earliest life history stages, and see which of these informal factors lead to coral death.

- [Narrator] Labs like Dr. Fogarty's need access to a lot of developing corals, and getting them from the wild has its own set of challenges.

Corals only spawn once or twice a year.

And something as simple as bad weather can keep researchers from getting out on the reef at the right time.

on land researchers use aquarium technology to control temperature, salinity, wave action, and even the sun and the moon.

- These LEDs have really been super important and revolutionary because they can allow it to seem like the sun is actually rising.

So that's what I'm adjusting throughout the year for intensity.

And then on top of that they also have their sun up and sundown cycles that they ramp through.

Then we have these lunar lights.

So they're just these little tiny LEDs that run across it, and they're super bright, but over the month it'll go higher and lower in intensity to really show like a full moon versus a new moon, and everything in between - [Narrator] Data from the wild is used to program these systems to make the corals feel like they never left the ocean.

- The computer just has inputs that you can set for everything.

Using data from South Florida, we made the seasonal variability.

That's when it starts to really think it's out in the wild still.

Usually we get to the point, we do our experiments when they're larvae, and then we put 'em back out in the water and we're done.

But now we're like, okay, we have 'em, we have these aquariums, let's keep them going.

Let's let's grow them out.

We have an infinite amount of time with them, so we can keep cultivating and seeing how they work.

- [Narrator] And the more we can learn about corals, the more likely it is we'll be able to give them a chance to survive in the wild.

- In the end we just need to really maintain genetic diversity, so if a new emerging disease comes up or there's some other stressor that we you have no idea, invasive species, some new pollutant, that we'll have some corals that are able to withstand it.

So what I like to remind people of is that we're not just spawning corals, but we're spawning hope that we can help corals recover naturally.

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