ADRIAN FLORIDO, HOST:
It's already been a summer of extreme weather events. This week alone, we've reported on scorching heat in the Southwest and deadly flooding in the Northeast. Today we're going to focus on the waters along the southeastern part of the country. Surface water temperatures along Florida's coast have reached some of the highest levels on record, and the consequences go beyond an uncomfortably hot swim in the ocean for beachgoers. It could also lead to a severe coral bleaching event, which in turn could cost the local economy billions of dollars over time. Katey Lesneski is here to help us understand why. She's a research coordinator for coral restoration at the Florida Keys National Marine Sanctuary, and she joins us now from Key Largo. Welcome.
KATEY LESNESKI: Hi, Adrian.
FLORIDO: I understand that you work in monitoring coral reef restoration and that you took a dive earlier this week to check what's happening underwater. Can you tell me what you saw?
LESNESKI: Yes, that's correct. So I was out diving almost a week ago right off Isla Murata, which is in the Middle Keys here. And upon just jumping into the water, I could feel at the surface how extraordinarily warm it is for this time of year. As we descended onto the reef, I started to notice some corals undergoing the first stages of bleaching. So we call that paling when they lose their color, and unfortunately, we're expecting to see much more widespread paling and bleaching and likely coral mortality in the coming weeks to months.
FLORIDO: What's going on with coral when it starts to lose its color?
LESNESKI: So coral is actually an animal, and it harbors in its tissue a symbiotic algae. And that algae gives coral the food, the energy that it needs as well as its brilliant colors. So when conditions aren't right - for example, exactly what we're seeing right now with higher water temperatures - that algae will leave the coral. So we're seeing the bright white skeleton underneath it. And if the coral can't recover - again, because it doesn't have its primary food source - it can die within a couple of weeks.
FLORIDO: Well, besides, you know, the obvious visual loss of the colorful corals and the potential death of the coral, you know, what are the broader consequences for the ecosystem?
LESNESKI: The broader consequences can be pretty dire. We lose the actual physical framework, the structure of reefs. Along with that, we're losing all of the habitat, all of the spaces that different organisms - that people care about as well. So anything from lobster to conch to the game fish that people come to Florida for will no longer have that habitat. Beyond that, with the loss of the coral reef framework, we actually see an increase of coastal erosion and the effects of waves during large storms.
FLORIDO: All of these things can have pretty serious implications for the economy in the Keys, I bet.
LESNESKI: Exactly. So it's estimated that, on an annual basis, just tourism related to coral reefs and coral reefs themselves can provide between 2 and $4 billion a year in annual revenue for the state of Florida. So we anticipate that, unfortunately, with the loss of reefs, there could definitely be a strong economic impact.
FLORIDO: You obviously can't really control the temperature of the water, but is there anything you can do to protect coral from the temperatures?
LESNESKI: So with this marine heat wave event and this potential bleaching event, we can actually use the reefs here as a living laboratory and basically consider what is likely to happen as a climate change experiment. So with coral restoration, a lot of the times we are intentionally determining which coral to put where, and with the temperatures and the potential for bleaching, we'll actually end up seeing which corals do the best during these scenarios. And we can focus science on understanding why those corals did well and then potentially incorporate them into future reef restoration efforts. Some days it is definitely hard to remain optimistic, especially as more data comes in every single day about the atmospheric temperature and the local sea surface temperatures. But with our efforts to really include projections on climate change, I do have optimism that we can restore these reefs with these projections in mind.
FLORIDO: I've been speaking with Katey Lesneski, research coordinator for coral restoration at the Florida Keys National Marine Sanctuary. Thanks for being with us.
LESNESKI: Thank you so much, Adrian. Transcript provided by NPR, Copyright NPR.
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