Two important reef-building corals will soon get a recovery plan from the federal government; Thursday the National Marine Fisheries Service released a draft blueprint for saving the elkhorn and staghorn corals, which are listed as threatened under the Endangered Species Act.
To find out what this means for reefs in Florida, WMNF spoke with Jaclyn Lopez, the Florida-based attorney for the Center for Biological Diversity.
“Yesterday, the National Marine Fisheries Service issued its draft recovery plan for two species of threatened coral. And these coral exist off the coasts of Florida and throughout the Caribbean; and they are the elkhorn and staghorn coral. So these coral are massive branching coral that make up the foundation of our reef system. And they have been listed under the Endangered Species Act since 2006. And this recovery plan which is actually still in its draft form — so the agency is accepting public comments to improve upon the draft — is the blueprint for bringing the species back from the brink of extinction and towards recovery.”
Our listeners might remember a story where twenty species, including some in Florida, were listed as threatened under the Endangered Species Act. But we are not talking about those; we are talking about two really important species that were already listed as threatened several years ago. One of the ways that they are threatened is from carbon dioxide pollution which is leading to climate change. How does that hurt these corals?
“Right. So, the recovery plan identified several ways that we can start addressing the threats against coral. You mentioned the really big one, which is global warming. And for coral this comes in two different ways; the two key things are: increasing ocean temperatures and ocean acidification. And so with increasing of carbon dioxide leading global warming, in the last century alone we saw about a 1.3 degree Fahrenheit increase in global temperatures. It’s predicted for this century that we’re going to get another five-and-a-half to eight-and-a-half (degree) increase in these temperatures. That’s significant for our oceans because they absorb about 90% of the Earth’s heat. So, what that means for corals that like to live — particularly these two corals that exist in the Caribbean — they like to live in waters between 66 and 80 degrees. And when they are exposed to higher temperatures over a longer period of time they start to self destruct. They eject the algae, which is symbiotic algae that helps them grow, and it leads to what is known bleaching.So, we have been aware that there are that bleaching events. That’s one of the things that has caused these species to decline precipitously in the last forty years. And when these corals bleach, they kick out their algae and they start to break down their skeleton and it just leads to complete coral reef collapse.
“The second big issue of global warming is ocean acidification. So as we continue to put carbon oxide into our atmosphere, our oceans absorb actually a great amount of that and it reduces pH, making the oceans more acidic. This is really important for coral because they’re calcium builders. So the way they get larger is by pulling calcium and making their skeletons larger. With higher amounts of acidification, you have these lower pHs, which means that corals are unable to rebuild as quickly. With the elkhorn and staghorn coral, the reasons that there are the anchors for our coral reefs is because they grow so quickly under natural conditions. They grow about 5 to 10 centimeters every year and they really are the building blocks of our reef system. With ocean acidification it retards their ability to grow. And when you have compounding factors, of like local factors for example with sedimentation and runoff and beach re-nourishment, impacts that inundate the coral, it impedes their ability to recover from these individual human-induced events.”
Before we move on from ocean acidification, I want to ask you about a comparison I have heard. Some people say when there is a lot of carbon dioxide in the atmosphere and the oceans absorb it, it’s almost like the oceans are turning into Coca-Cola. Why do they say that?
“Right, exactly. So it’s the effect that having this increased acid has on these calcium bodies. And so, it degrades the calcium that exists in the water and it makes more difficult for the coral to rebuild their skeletons. And I understand that you did have Dr. Shae, a climate scientist, on who was talking about ocean acidification and temperature changes and the impacts to coral. She referred to coral as the rainforests of the ocean. And that’s true for a few reasons. So, with the elkhorn and staghorn coral, particularly off our southeast (Florida) coast, they are like rainforests in that they produce to provide this really complex habitat for a bunch of other species. So, everything, from the macroalgae all the way to the big fish that we like to observe and recreate with and fish. And for other reasons as well, so like our rain forest in the Amazon, rainforest being coral in the ocean provide us with scientific breakthroughs. So there was one of the earlier AIDS treatments that was developed, that came from sponge reef. And that came from the Caribbean. So these coral present us with these really interesting ecosystems that attract other species, making them really biodiversity rich, which provide us a lot of opportunities for scientific exploration, recreation, tourism, as well as now with the increasing sea level rise they also provide us a buffer from encroached seas.”