Islands on the Move: The Barrier Islands of Gulf Islands
Transcript
Michael: Welcome to the Sounds of the Gulf. The podcast that stretches a hundred and sixty miles at the largest National Seashore in America, Gulf Islands National Seashore. Your National Seashore. Did you know that Gulf Islands National Seashore encompasses multiple barrier islands? From Santa Rosa, to Horn Island, to Ship Island. These barrier islands are very unique. And today, my guess, Jackson, will explain what these barrier islands are and also the, let me give me a second. He sent me this word. The coastal geomorphology.
Jackson: That's right. That's your power word for today. Good job pronouncing it. To explain a little bit, geomorphology is simply the study of how terrain is made and there's no better place to study how terrain is formed than these barrier islands. They're so unique. I'm so excited to share with y'all how they're made.
Michael: Thank you so much for coming on podcast. Before we start, why don't you give the listeners out there a little intro about yourself?
Jackson: Yeah, absolutely and I love talking about myself. So, thank you for this opportunity. My national park story really begins in the 2020. The coronavirus and the pandemic that ensued, gave us all really a chance to go out and explore the great outdoors. And I was certainly no stranger to that. I took advantage of this. I traveled around the country, because, you know, we all had a little bit of free time then. And I explored the beauty of America's National Parks. One of the things that really struck me on my travels was park rangers. They were so informative. They were so passionate about their jobs, and they were excited to share all of that with me and the rest of the public. And I always that stuck with me, and, you know, I was like, you know, I want to be a park ranger too. I'm passionate about this. I want to go study, and I want to share what I find with the public. So, years past, I go to college in the fall of 2020 and, you know, life happens effectively. You know, you change your major six times in a semester. you begin to not want to be, you know, what you thought you were going to be. So, I became a history major. Graduated with my bachelor's in of history in May 2023. And I took what I thought was going to be a summer job here at Gulf Islands National Seashore, but it turned out to be a life defining moment. This job has allowed me to rekindle my fire to be a park ranger. I've loved it. I've loved the enthusiasm here. I loved working outside and with the general public people that share the same interest and passions as me. And it's just been a amazing experience. So, I hope to turn this into a full time thing, even though I'm just an intern, I want to go on and do more in the park service. So, this has been a great moment for me.
Michael: Thanks, Jackson. I know I can relate and probably a lot of listeners with changes in life plans and thinking about what you want to do. Great that you have this passion for National Parks. And part of that passion has been do creating this program about barrier islands. So, could you explain just really quickly what is a barrier island and how is it different from what most people would think of as an island?
Jackson: It's different because it's better. No, I'm joking. barrier islands are very unique structures. They're very fragile. They're very young. I believe these barrier islands are less than ten thousand years old from, Mississippi to Florida. These islands form in pretty much the same way. Glaciers that formed in the last ice age in the Appalachian Mountains. When they began to melt, they began to form a river, the Apalachicola River. These deposited grains of quartz that were shredded over time and became so fine that they became like a powder. Longshore currents that run, east to west then picked these up from the Apalachicola River and move them westward just like the rest of American history, seemingly. But they eventually began becoming deposited. They would form these Peninsulas in the Apalachicola River Basin, and they would be transported along the Gulf of Mexico, making their westward journey to where they are today.
Michael: So, one of the big differences is the sand here at Gulf Islands National Seashore. The sand is almost completely white, and that's because of the quartz. so that's also one of the unique things, but just the sand isn't the only thing that's unique here. Could you explain what's below us right now? So, we're on a barrier island. What's below us?
Jackson: So, anybody that's been to the beach probably knows about sandbars. They're a little raised platform. They're still underwater. Barrier Islands are unique because they're like aboveground sandbars. They get their shape over the course of thousands of years. So, if you were to walk from the beach side where, it all begins to the bay side where the process is still taking place today, you would be experiencing about 6000 years of history walking in that direction. So, they begin to form as sand from either wind or the same longshore currents that go east to west. They pile up sand on these sand bars. They deposit it, and they form these big structures called primary sand dunes and they’re primary because believe it or not, they're the first. So, these primary sand dunes, they sit right on the gulf on the beach side. And they're really the reason why this island exist. Now, Michael, if I were to spray salt water in your face, would you like that?
Michael: No. I would not like that.
Jackson: Honestly, neither would I. And most plants also don't like this, but there's one in particular that can survive these salty conditions from the salt spray from the ocean, and these are sea oats. Sea oats are the most valuable thing in my life because I live in Pensacola, I need a barrier island to protect me from incoming hurricanes and storms. Barrier islands help absorb the impact from that. And barrier islands are held together by the sea oats. You're Michael, you are from the Midwest. Are you familiar with a crop or plant called wheat.
Michael: Very. Anyone who's driven in the Midwest knows, probably too much about what wheat looks like.
Jackson: Yeah. that's a good way to put it. So, you probably are familiar with wheat, how it looks. Sea oats are kind of like that, they're also a grain, believe it or not. And, but they're a little more green, but the magic isn't really them themself. It's under that. Their root system holds those primary sand dunes together. If those were not there, the dune would fall apart. The barrier island would fall into the ocean, and the next time a hurricane came through Pensacola or other areas that are protected by them, they would be subject to a huge storm surge that the barrier island cannot absorb.
Michael: Fascinating. It's crazy to think that such a small plant that looks just so generic is so important to the island. And if we're talking more a little bit more about the sea oats, since they play such an important part, how should people and listeners out there interact with sea oats?
Jackson: In not very many ways. Interaction with them is, you know, you may take pictures with them. They like they look great in photographs. I know I'm in plenty of them. But because these sea oats are so important and there's not a lot of them left, we at the National Parks Service discourage heavily. Taking them, touching them, pulling them out of the ground, taking them home as souvenirs. It's a hefty federal fine to do it. So probably not worth it in that sense, and it is an offense. So, you may look and observe them. You may take pictures with them, but please don't rip them out of the ground. Michael: And even going even further, don't even, leave a footprint on them. We like to say the leave only footprints on the beach does not apply for the sea oats. It's best to preserve them and keep them together because that's the only thing keeping this island together. So, talking more about the barrier islands, you talked about these primary sand dunes. Are these the only sand dunes here on the islands?
Jackson: They are not, good catch. Behind the primary sand dunes lies little shrubs called that we call beach sheep, but they're allowed to form because those primary sand dudes knocked down, salt spray from the ocean, allowing more plants to flourish. Now beach sheep is some of the only shrubs and plants that can survive behind them. Thankfully, we are gifted secondary sand dunes, which are even bigger. They can reach over 100 feet tall if they're allowed to go, untouched by humanity and nature. And they are really the thing holding this island together as far as the habitats go. They can again hit over 100 feet tall. and they form in pretty much the same way just several years after the fact from those primary sand dunes forming. Behind those, you'll start to see habitats develop. near the secondary sand dunes, you'll see things called salt pans. This is when in, say, a high tide or maybe a flood, if there's a hurricane, salt water will go on to the barrier island. It'll sit in a certain spot and allow a habitat to form. However, there's not enough supply at this point of the water, so it'll evaporate, leave behind the salt, and the environment that it's created. It's it looks more like a desert. If you drive into at least, the Santa Rosa Island portion of Gulf Islands National Seashore on your way to visit Fort Pickens, you'll probably notice the batteries there like Battery Cooper, Langdon, and 234. Those are also all secondary sand dunes. They catch sand in much the same way that the primary ones do. And they also help protect the environment. So, nature has really conquered those, forts that humanity built. And secondary sand dunes and primary sand dunes also exist on most barrier islands, not just Santa Rosa, but ones in Mississippi as well.
Michael: There's more than just sand dunes. There's actually a difference between secondary and primary. Talking more as we get more inland, could you talk more about how these islands develop? Especially if you go on these islands, you might notice trees. There's almost a forest here. Could you talk about how we get from just a pile of sand and the progression into a wooded area?
Jackson: Yeah. So, barrier islands, you wouldn't think is conducive to having a forest environment. But if a barrier island is big enough and well protected enough by those sand dunes, eventually, the wind from the ocean dies down, there isn't as much salt spray, and you get some larger and larger plants to form. These kind of coalesce into a habitat known as the maritime forest. The trees there are very diverse. We have magnolia. We have oak trees. We have pine trees. The Gulf of Mexico and the southeast was famous for its longleaf pine trees, which were not exactly the same size, but quite similar to the Redwoods out in California. However, the lumber industry took those down. We may talk about that later. But the forests here have a very rich history, especially on those barrier islands. The closer you get to the bay, the younger the environment is, but the taller the trees get, which is kind of weird to think about because that environment mimics the mainland environment very similarly because of that protection by those primary and secondary sand dunes.
Michael: Talking about the environment there's a lot of different types of environments here on the barrier island. What does that look like? And how does that impact the wildlife? Is there different biomes? Is there different species? Could you give us a brief explanation on that? Jackson: So, there are several different habitats. I've already touched on the salt pans, the dunes, and the maritime forest. Believe it or not, there are also more environments. So, barrier islands contain marshes. I have a question for Michael if he's up for the task. Do we have on barrier islands, do we have salt water marshes or freshwater marshes? Michael: Well, since I know we're on the ocean and even the bay is salt water, I might have to say we have saltwater marshes. Jackson: So, I'm a terrible podcast guest. I asked a trick question. The answer is both. Pensacola Beach, for instance, is one of the most rainy cities in the world or in the United States. So, rain comes often. It piles up into these marsh. Well, it'll make a marsh. It piles up into spots. It'll make a marsh. Plant seeds that come from either the mainland via the wind or maybe animals that like birds that fly to and from the mainland to the island will deposit these seeds and they're conducive. They're able to give life and the seeds will spread, and it'll make a whole environment. There's tadpoles and minnows in the marsh, but beyond that, it's not really a place for you to get dinner. Herons, on the other hand, and egrets that hunt tadpoles and minnows, can find food there. So, they're able to survive in those areas and thrive in those areas. Beyond that, there's, as Michael said, saltwater marshes. Now the big distinction is the salinity, as you can imagine, but maybe more so than you would think. When there's high tide or there's flooding from a storm, fresh water marshes will actually turn into brackish or salt water marshes because the sand or the salt water from the ocean gets into the freshwater marsh. So, most of the habitats here are actually some degree of brackish water. And saltwater marshes are very similar to freshwater marshes in that, it's a marsh. It's surrounded by water. There's actually small creeks that can form on these barrier islands. Michael: Now talking more about human impact. Could you explain how tourism kind of impact these islands? Jackson: They don't, do a very good job impacting it, or they don't do it for a positive reason, I should say. And to start us of nature also impacts these barrier islands. Residents of Pensacola and the surrounding Gulf Coast areas may remember the dynamic duo of hurricane Ivan and hurricane Dennis in 2005 or 2004 and 2005. The 60 and up to hundred foot tall sand dunes located on Gulf Islands National Seashore were almost entirely blown over. Now the islands didn't lose the sand. it stayed on the island in some form or another. It's just that the sand dunes were wiped out. Ivan knocked those down. Dennis didn't really do much damage because the damage had already been done, and nature did not have enough time to heal itself. Thankfully, you can think of these barrier islands as not sentient organisms, but they do try to preserve themselves from falling into the ocean. If they run out of sand, they're going to move more inland, where there's higher concentrations of sand, and these sand dunes are also going to form over time because those winds and the longshore currents east to west are going to move sand and reform those dunes. The problem is that humanity has not been the kindest to these barrier islands in recent years, and that stopped some of these sand dune regenerations from occurring. In the 1950s, Pensacola began to become a tourism hub with these tourists brought the real estate developers with these developers brought bulldozers and condominiums. They knocked down those pesky sand dunes because who comes to Florida to climb mountains? You want to go to the beach. Why would you want to walk uphill to the beach? So, they knocked down the sand dunes and they tried their own artificial ways to curb shoreline erosion. The problem is, is that these didn't really work very well. It's really a game of domino, because though they could stop sand from going out into the ocean. As previously mentioned, these currents that bring the sand from the east end of the island to the west end of the island now had their sand deposits trapped by an artificial structure. So, the west end of the island could not get the sand needed to replenish itself. So, humanity has kind of over the past, couple decades really harmed the way that barrier islands have grown. However, we’ve kind of realized what we're doing wrong, and we're trying our best efforts to restore the barrier islands to their, former glory. We're we no longer have to replenish the beaches by taking a slurry of sand and water out from the ocean and dumping it on. We're beginning to we, as in, Florida and the federal government are beginning to plant sea oats along the beach and try and bring these islands back together. Beyond that, there's then efforts to curb littering here. Michael, would you like to go to a beach covered in plastic and glass and food? Michael: No. That sounds terrible. Jackson: No. not really. I mean, I used to live in Arkansas. Those areas aren't exactly the cleanest, and that's why I don't go there anymore. But if littering has been curbed and hopefully, we can keep littering from being curbed to preserve the beauty of this barrier island. So future generations can come and experience it the same way that you and maybe your parents, if you've been visiting for a while, were able to. Michael: Talking about littering. I know that littering really impacts the ecosystems and wildlife, but in ways that many people don't even think about it. Jackson: It impacts it in a huge way. Many of the animals here are very endangered. The Santa Rosa Beach Mouse being one in particular. There's only a couple of those left. Shorebirds, Snowy Plovers that are critically endangered. We've been trying to get those population numbers up. However, their biggest predators being crows and ravens, they feast off of litter. So, let's say if I, I'm being very bad and not conservation minded. I throw my hamburger on the ground. Well, that's going to attract crows that come in. Crows will stay on the island. Crows will eat snowy plover eggs, and they'll also get into sea turtle eggs and, you know, who doesn't want to save the sea turtles? So, if we litter, it's going to bring all these invasive species in. But if we stop littering, we're going to be able to drive them away. And the wildlife here is going to be preserved for yourself and, hopefully, future generations that come visit here. Michael: That's fascinating to hear about crows and invasive species. When I think of littering, I just think of the plastic straws and the plastic containers and birds or some kind of endangered animal, eating it. But you've kind of shown that even food littering and stuff that we think is biodegradable drastically impact the barrier island. We're, running a little low on time. So, the big question I do want to ask you at the end is, how do you hope listeners out there interact and respond to this episode on barrier islands? Jackson: So, I hope that when they come and visit these barrier islands, they appreciate not just the beach. Or the area that probably most people come in for it, but they take time out of their day to walk through to experience and time travel a little bit from the beach to those primary and secondary sand dunes and see how, life begins to spring up the further away you get from the ocean. I also hope that, you know, they're able to experience the diverse habitats and wildlife that form behind those primary and secondary sand dunes. I hope that they're able to take away an appreciation for nature in that setting. And I hope that they're able to understand how fragile these ecosystems are. and how important they are, and barrier islands are to not just the communities that live on them, to those on the other side of the bay. And I also hope that they begin to be conservationally minded. They're aware of how fragile this all is, and they understand the impacts that human and nature has on it. And most importantly, I hope them that these people, when they come to Gulf Islands National Seashore and experience, our barrier islands, they're part of and not just part of, but they can be the solution to many of the problems that these barrier islands face today. Michael: Thanks, Jackson. Yeah. The conservation and the ability to change is such a huge thing here. The island and the beach is never the same day to day. And it's always changing. It's always shifting. And so, as Jackson showed, the island's always changing. So, the question is not whether or not it will change, it's how will it change and how will us as guests and visitors to the National Parks be part of that transformation. That's all the time we have for today. Jackson, thank you so much for being part of this podcast.
Jackson: Thank you for having me on, Michael.
Michael: And to you listeners out there, thank you so much for listening to this episode. I hope it was enjoyable and that you learned a little bit about barrier islands. I hope as you enjoy this, your natural seashore here, that you take some time to appreciate not just the beaches, but also all the other environments in ecology that go into the barrier islands. So, let's get up. Let's get out there and let's explore this great national seashore.
Gulf Islands National Seashore encompasses multiple barrier islands? From Santa Rosa, to Horn Island, to Ship Island. These barrier islands are very unique. Explore what these barrier islands are and also coastal geomorphology.