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Reef Resilience

Diving Deeper: Episode 67

Several species of reef fish nestle in a cauliflower coral in American Samoa

Coral Community

Several species of reef fish nestle in a cauliflower coral in American Samoa.


HOST: Welcome to Diving Deeper! I’m your host Kate Nielsen. Today, we’ll talk about coral reef health, specifically how reefs respond to stressful events like coral bleaching. Joining us today is Britt Parker, a climate specialist with NOAA’s Coral Reef Conservation Program.

Hi Britt – welcome to our show!

BRITT PARKER: Thanks for having me.

HOST: Britt, to start off, can you share with us some of the threats our coral reefs are facing today?

BRITT PARKER: Sure. We think about threats kind of both locally as well as globally. So some of the local threats we’re really concerned with are things like unsustainable fishing practices or land-based sources of pollution, this could be both things like fertilizers and excess nutrients as well as sedimentation, so run-off from the land. We’re also very concerned with the global threats related to carbon dioxide in the atmosphere including global climate change and the warming of both the atmosphere and the oceans and ocean acidification which is a related problem. And so all of these things, both on their own as well as taken together, can have great impact on the health of coral reef ecosystems around the world.

HOST: Great, thank you. In the introduction, I mentioned how we’re going to talk a little bit today about how reefs respond to stressful events, like coral bleaching. Just to get everybody on the same page, can you tell us what happens to a coral when it bleaches?

BRITT PARKER: Certainly. So one of the main impacts of climate change again that increasing atmospheric and ocean temperatures is something we call coral bleaching. Coral reefs as an organism actually have these tiny algae called zooxanthellae which live within their tissue. And when a coral is exposed to temperatures above the normal warmest temperatures its use to, especially when conditions are really hot and still and lots of high intensity light, the coral will actually eject those algae. And the problem with that is that those algae are actually the source for much of the food and nutrients that the coral requires to survive. So, in this case, the stressful event that we’re talking about, this coral bleaching, if the coral are in these conditions where they are bleached and these last a long time, then the coral can actually starve and die.

HOST: Britt, is it possible for a coral reef to recover from a stressful event maybe coral bleaching like we talked about or one of the others from your first response?

BRITT PARKER: Absolutely. It is possible for a coral to recover, and in fact it’s also possible in some cases for them to resist the event and not bleach or not bleach as badly. So, when I think about this, I like to think about our health as human beings. When we are under really stressful conditions—we haven’t gotten enough sleep, we’re not eating well, we’re not exercising, work’s tough, there’s a lot going on with family—and we’re exposed to a cold virus or something similar, we can get pretty sick from that, be kind of down and out for a number of days. But if conditions are really good for us and we’re not really stressed, we may actually not get the virus once we’re exposed or we may only have a small cold that only lasts for a couple days.

And so, coral reefs are very similar in that, if conditions are right, they have good water quality, we’ve taken care of those land-based sources of pollution and sedimentation, if they have the right types of fish on the reef (and we can go into that a bit later), but we’ve controlled some of the unsustainable fishing practices, even though a coral is exposed to higher than normal temperatures and might bleach, once those thermal stress subsides and water temperatures go back to normal, it actually can recover. And it has the best chance of recovery when all other conditions are optimal for reefs.

HOST: Why are coral reefs important to us? To everybody in the United States as we’re talking about this episode, not just people who live in coastal areas or areas where there may be corals. Why should we care?

BRITT PARKER: That’s a really great question, especially for those who may not live right on a reef. But coral reefs, just basically, are what we call hot spots of biodiversity. So from a scientific perspective, they are these amazing places, much like the rainforests of the Amazon where there’s all sorts of species living in close harmony if you will with the reef, using the reef structure, and many of these we’ve found to be really important for things like components of drugs that treat things like cancer and that’s something I think we can probably all identify with. But for those who live near coral reefs, they provide a lot of tangible benefits. So a lot of people are very dependent on the fish that live on reefs for sources of food. There’s the tourism industry, those who are dependent on having divers come and vacation. Many beaches are actually made of pieces of coral reef that have been broken down over time so those beautiful sandy beaches that we all like to vacation on are partly due to the existence of coral reefs.

In addition, in a lot of places in the islands in the Pacific and the Caribbean, there’s a very strong cultural tie to the reef, and there’s history and there’s stories that have been passed down from generation to generation, it’s part of the cultural identity of the people. And finally, I think one of the things that we might not think about, but we’re thinking a lot more about now as we see increasing storms and hurricanes and storm surges and flooding, is that, those areas that have reefs off of the shore, those reefs actually provide significant shoreline protection in that they can dampen the waves or make the waves coming into the beach smaller and prevent erosion.

So, it’s because of the importance that coral reefs play for people all around the world that we’re so concerned about reef health currently with all of the different threats and stresses that reefs are experiencing. And so, we like to think about this in terms of how resilient reefs are or how we can manage them to be more resilient. And what we mean by that is that they’re healthy, they’re in the best possible conditions to allow them to either recover from stressful situations or do their best to survive these types of impacts that we’ve been talking about.

HOST: Britt, what is the role of your program, NOAA’s Coral Reef Conservation Program, for healthy reefs and building these more resilient coral reefs?

BRITT PARKER: Basically, the first thing that our program really tries to do is understand the health or current condition of reefs, so kind of where we’re starting from at this point. And so we do that with monitoring programs and such, helping the local managers understand the condition of their reefs. We also do a lot of science and research to better understand what we call reef resilience—so that ability of a reef to either resist or recover from a stressful event and to continue to provide the benefits to people.

So we do a lot of science to better understand reef health and resilience and what factors can make a reef more resilient. Recently we’ve started working with local partners to do what we call resilience assessments, which is to do a special kind of monitoring on the reef to understand what areas of reef are more or less healthy or resilient and what are the priorities for managers to take action with communities in order to increase the resilience of those reefs that perhaps aren’t as healthy. And we also want to help support our local mangers then in taking those actions to increase reef health on the ground. It’s kind of cool because we’re working with partners both within the United States and internationally on these issues and trying to better understand the challenge of managing reefs and taking care of our reefs in a changing climate and how we best do that together, so there’s quite a cool community of people who are working to save reefs in these times.

HOST: How is this working so far in local communities? Are there any success stories you can share with us today?

BRITT PARKER: Sure, I think one of the challenges is, with coral reefs as well as many other ecosystems, we don’t necessarily see immediate results, it takes a lot of time to increase ecosystem health. But one example is a community in Maui looking at an area called Kahekili, so I mentioned earlier that it’s really important for coral reefs to have certain types of fish on the reef. And one group of fish that’s really important, they’re called herbivores and they’re called herbivores because they actually eat plants. So they eat the algae off the reef and make room for new baby corals to settle and grow. In areas where you have a lot of runoff from agriculture or just generally a lot of sedimentation, you can have these blooms of algae which outcompete for areas on the reef and the baby coral can’t settle.

And so Kahekili was one of these places where they didn’t have as many herbivores as they had in the past, they were seeing the coral cover of their reefs drop and it was really important to them, the community, because there are a lot of subsidence fishers, a lot of native Hawaiians, who had depended on that reef for many generations as well as a lot of tourism industry in that area. So there was a large group of people who it was important to keep that reef as healthy as possible. So working with the Hawaii Department of Land and Natural Resources and their Division of Aquatic Resources and with the community, they decided to set aside an area and protect that area from fishing of herbivores, from feeding fish (because they would want the free food much more than they would want to go work for it on the reef and eat the algae) as well as a few other actions. So that was put into place a number of years ago and they’re just starting to see some indications that the reef health is actually getting better in part because of those management actions.

HOST: So, we’ve talked now about a few of these local examples of local managers and their roles to help support more resilient reefs in these communities. But, our listeners here today, Britt, they may be interested to hear if there’s something that they can do as well to help coral reefs.

BRITT PARKER: Absolutely. You definitely don’t have to live in the coastal area or near a reef to take actions that will actually help reefs. So we’ve talked about one of the major global threats to coral reefs is climate change. And so anything that you can do to reduce your carbon footprint would be huge in helping reefs survive into the future. So things like riding your bike and driving less, recycling, using energy efficient appliances and lightbulbs, and things like printing less and using less paper, so just any action that you can take to be a bit more conservation minded about how you’re using natural resources. So that’s a big one.

In addition, there are other things we can do to improve reef health, especially if you live in watersheds, so those areas where runoff and what you do inland can affect what’s happening on the reef, and that’s pretty much everybody. So things like reducing how much fertilizer and chemicals and things that you use on your lawn. Not dumping household chemicals down the drain. There’s also things you can do like choosing sustainable seafood, so making sure that the seafood you’re eating isn’t contributing to those unsustainable practices for fishing on the reef that we’ve talked about.

Another thing is that whenever you visit a beach or an area that has coral reefs is to think about how you are interacting if you’re on a reef snorkeling or diving, making sure you’re not kicking the reef/stirring up sediment. Taking pictures and enjoying yourself, but not leaving trash and other things behind. And then you can always do things like volunteer for beach and waterway cleanups which will help keep debris and garbage off of the reef which also can physically damage the reef. So those are a number of things that just about anyone living in the United States, no matter where you are, can do.

HOST: Thanks Britt, those are some really good suggestions and many ideas that we can take. For our listeners today, if you go back and look at our show notes, we’ll be able to link you out to an infographic to provide a recap of some of those suggestions that Britt has given us. What I like to do with everyone that visits us on Diving Deeper and talks a little bit about their work, is get an understanding of how you got to this position today? What brought you to NOAA? What just inspired you to work in this field?

BRITT PARKER: Sure, well I think that the earliest indication that I was interested in coral reefs came as an undergrad when I took an evolutionary ecology class and we had a guest speaker, Dr. Danny Gleason, who’s actually now at Georgia Southern University, and he gave a really interesting talk on coral reefs and so I approached him after the class and asked him if I could volunteer in his lab and I started working to process some of the early samples that were taken to try to understand the phenomena of coral bleaching so that was pretty cool. And then I ended up going to grad school for a more general marine science background and worked at the Virginia Institute of Marine Sciences for many years on water quality in the Chesapeake Bay when I had the opportunity to come to NOAA and to start working on issues around climate change and coral reefs.

So I think one of the things that has really inspired me to continue to work on coral reef and climate change issues are the people that I’ve met and worked with from local communities who are so dependent and tied so closely to coral reefs to those in the Pacific Islands who are experiencing the impacts of climate change in undeniable ways at this point for them and their communities. And that’s really I think where I keep the energy up and that’s what inspires me to keep working on these issues today.

HOST: Thank you. Britt, do you have any final, closing words to leave our listeners with today?

BRITT PARKER: Sure. I think it’s really easy right now to be somewhat depressed by what’s happening to coral reefs around the world. We have experienced the 2015/2016 global bleaching event. We’re seeing a lot of headlines in the news about the conditions of the Great Barrier Reef in Australia as well as reefs around the United States. And so, I think it would be easy to kind of buy into the gloom and doom, and it is a very serious situation, not to minimize that, but I think it’s really important to remember that the actions that we take locally and that those communities around reefs are taking to protect their reefs are extremely important in buying time for reefs as the global community works on stabilizing climate change, and with things like the COP-21 agreement in Paris to reduce greenhouse gas emissions.

And we will lose more reefs, there’s no way around that, but I think that this is a really bright spot of hope in the future – our commitment to stabilize our climate means that those reefs that do survive the next 20, 30, 40, 50 years will be the hope for reefs of the future. And so I can’t overstate the local actions to help preserve reef resilience and reef health. I think that we all have a role to play in conserving and protecting reefs and I like to think about any actions that we’re take to help reefs, help other ecosystems and help make the planet better for us as well.

HOST: Thanks Britt for joining us today on Diving Deeper. For our listeners, please see our show notes for links and more information on reef resilience. That’s all for today’s show! Thanks for tuning in!

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Connect with ocean experts in our podcast series that explores questions about the ocean environment. Get ready to Dive Deeper!

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