Ranger: My name is Larry Perez and I am a ranger with Everglades National Park. And, I do a lot of education and outreach work for invasive species in the area. We are right now at the Anhinga Trail which is one of the most popular visitor areas in the park. What a lot of folks do not realize is that some of those animals that they are seeing out here on the trail and some of the plants are not only nonnative to the area, but they are actually species that we are trying tirelessly to eradicate from the park. Native species are those that either have occurred, now occur, or may occur in a given area through natural processes. And, that stands in stark contrast to an exotic species which is one that occupies an area either directly or indirectly as a result of human actions, be that, intentional or accidental. Fortunately for us, the vast majority of exotic species do not adversely impact the ecosystems that they are introduced to. But, those that do are generally termed invasive species and in terms of management, those are the ones that we typically target. The park has been actively engaged in managing nonnative exotic species for decades now and it remains at the forefront of our efforts here as far as resource management. In a moment, we are going to show you a few of those more high-profile species and some lesser known species you may not have heard about and take you out in the field with researchers to show you what we are doing about the problem and how we are day-to-day managing this very important issue. Biologist: Where did he go? Biologist: Is that not amazing? That guy was almost 12 feet!? Yeah, 12 foot snake…vanished. So, we are releasing these snakes with tracking devices in them so we can view where they are going, how far they travel, what kind of habitat they are using. The next reason is because a lot of time, a male will lead us to more females or vice versa. So, release one…catch multiple. We really want to learn more about these animals and study their movement and study their habits and habitat. It is giving me the same thing. I think it might be further out here. 90…92…95… Biologist: Burmese pythons, I think can be summed up right now where we are with them: As you may or may not know, they are an invasive species. They come from Southeast Asia. They come here through the pet trade…either intentional or unintentional releases. Some combination thereof perhaps…we will never know exactly how they got released. Showed up here deep in the park in the mid-1990s. Maybe we have information that suggests they may have even been here as early as the mid-1980s. Needless to say though, they are here as a result of the pet trade. They were brought in here, imported and then bred locally through captive breeding and distribution for sale. They were purposefully imported like a lot of other exotic pets and found their way either intentionally or unintentionally into the wild. It is hitting hard right here, really hard. There is the snake right there. See it? Coiled. I don’t think they provide any more of a danger to humans than the dangers we already have out there. I think that is an important point to make: It can be a dangerous place whether it is reacting to bee stings, hydration, whether it is the pinnacle rock, or whether it is an alligator or any of our venomous snakes. There is a reason to pay attention to what you are doing! He just popped his head up right here. You can see his head. He is taking bubbles… Biologist: Those are all jewelfish. Volunteer: Amazing, wow, they are beautiful. Oh, look at this: They color up. So, these are our African friends? African jewelfish. Volunteer: So somebody put them in the aquarium and then they got in here? Yeah, what is the best theory these days? Probably the aquarium industry. In 2000, we first collected the African jewelfish within Everglades National Park. Within this ten years that the African jewelfish has been in the park, it has really become one of the most abundant freshwater fish within the shorter hydroperiod marshes. Have they shown any impact? Have they had any adverse impact? We don’t know, yet. The numbers that we tend to catch them in some areas suggest that there could very well be an impact. We have got a park-wide monitoring effort. We are looking primarily to find a lot of these non-native species and to see how their distribution changes over time. So, we’ve had this big park-wide sampling effort going on since 2004 and we have been able to track how the African jewelfish has been spreading in the park. It is a female Marsh killifish and she is filled with eggs. You worry that it is a problem but it is hard to know if it is a problem. I am extremely curious about the degree to which it is a problem. I think the problem would be if the new fish that are introduced are extinguishing all the native species. We found pockets of water, certain sinkholes here, where we would pull out ten or fifteen African jewelfish to just one or two native sunfish. So, it is pretty surprising to see. It is very interesting…some of the introduced species are extremely colorful and they are interesting in their own right too. Biologist: Originally, it is from Australia and it was introduced to South Florida in the last 1800s by humans. And, it is still here today. The reason that it can be a problem is it can displace the native vegetation. Some of the top invasives that we deal with are not only melaleuca, but we also have Brazilian pepper, Australian pine, Lygodium, also known as Old World Climbing Fern. It is part of the mission statement of the National Park Service is to manage for invasive or non-native/exotic species. So, it is also part of the National Park Service’s mission to preserve the native habitat. The best way I think to try and control it is using an integrated approach to it. So, we will use both mechanical methods to chop at the tree and either cut it down or we will just girdle it. And then, we will use an herbicide. This tree right here now should no longer exist. You can not just go through and treat it once and then turn your back on it. You gotta make sure that you are continually monitoring the areas that have been treated. And, you try to get back to them for some follow-up treatment and that is where you can really make your progress. These are walking catfish: They are a non-native species. We had a big rain shower this morning. So, they are probably trying to relocate from a hole where they were in the water. And trying to find a bigger body of water to persist through the dry season. These ended up on the road and some are stranded on the higher ground areas where there is not much water. They don’t seem to be able to always find the better habitat..the grass is not always greener, I guess. This morning we are going to go out to an area on the western part of Everglades National Park where we released a biocontrol, the Brown lygodium moth. That is a biocontrol for Old World Climbing Fern, or Lygodium. As we are flying, I’m going to be looking and monitoring or surveying just for general other non-native plants that are out there. Within Everglades National Park, we know there to be just a little over 1,000 different species of plants. And, of that, a little over 200 of them are thought to be non-native. We estimate that there is about 200,000 gross acres of land infested within that million and a half acres with some type or another of exotic species. The area that we released the biocontrol in is one of the higher levels of infestation of Lygodium that we have within the park…which is one of the reasons that we released the biocontrol there. There is not a lot of roads out there to get us to where we need to go. The remoteness and inaccessibility is definitely a challenge. We first detected Lygodium within Everglades National Park in 1999. And, at that time, we estimated the coverage of Lygodium to be around 200 acres. And, presently we estimate it to be around 10,000 acres. This is Old World Climbing Fern…otherwise known as Lygodium microphyllum. Some of the features that I use to recognize it are it is this bright, green color typically. And, it has these fine, delicate looking leaves. It tends to climb up other plants and use them for support. And, this is a good example. It has just shown in other habitats and in other areas that it has completely overgrown tree islands where there is literally nothing but Lygodium. But, again, it is such a challenge just to get out here and try and figure out what is going on with this one specific spot over the whole, huge landscape of the Everglades…it is not easy. It is a fantastically beautiful landscape. If you look around, there are birds flying through the sky and the herons and the egrets are hunting in the corners. And, the Everglades team has just been fantastic to work with. These biologists are unbelievably dedicated and they are out here day after day, year after year counting the fish so that we can be sure that the habitat remains beautiful. I would hope that the Burmese python is used as a poster-child, a poster-snake, for this larger issue of are we doing the right things and do we have everything in place to prevent this from happening next time. Whether it is laws, regulations, education, outreach…whatever it might be, the tools to respond. All of that in a package, lets try and avoid this. It was about an 11.5 to 12 foot snake and as soon as it hit the water, it was gone. Some people suggest: If there is a python problem, why don’t you just run out into the Everglades and catch them all. But, that right there just proves that it is not that easy. There could be a 15 foot snake behind you right now and you would not see it. Filmmaker: Or, behind you!? Yeah, there probably is.
Researcher: One of the things about snakes, and pythons are no different, is that snakes are often hard to find. And, one of the best ways to find snakes is to try and cover as much ground as you can when snakes are out and when they are active. And, for most of the year, these snakes are active at night because during the daytime, it is just too hot down here. So, if we drive the roads at night, we can cover a lot of ground in a relatively short amount of time and increase our probability of finding snakes. The biggest impact that pythons have is the fact that they are large predators. And, they can eat a number of animals. They most frequently eat birds and mammals. And, they have already been documented to eat species of special concern and endangered species that are species we are concerned about here in South Florida. And, so the impact on endangered species is a real concern. But, also just the impact on the ecosystem by them eating common species. For example, rabbits, raccoons, and possums now appear to be relatively rare in Everglades National Park. And, in the 1990s, they were relatively abundant. And, whether that is due to the pythons or not, we do not know for sure but it appears to be correlated. And, the impact of those species disappearing from the park or at least having their populations reduced substantially is really unknown at this time. I have always been interested in amphibians and reptiles, and especially in snakes. And, so, anytime you have the opportunity to study a really large snake, you know, it is a lot of fun. Although, this is a real mess down here because of the pythons. So, the other aspect of that is that this is really interesting just because you rarely get a chance to study or address biological questions related to the introduction of a species such as a python which is a large cold-blooded, or ectothermic predator that can occur in very high densities. Most of our large predators occur in relatively low densities…things like panthers and bears. Alligators are an exception, they occur in relatively high densities in certain places. But, these snakes have been introduced and their populations have expanded rapidly. And, they have already become a relatively common snake within Everglades National Park. One of the things that we noticed just recently is that over the years since 2005 that we have been driving the main park road looking for pythons is that we find very few, if any, raccoons, possums, and rabbits. And, going back and looking at data that was collected in the 1990s by park rangers, they found road kill possums, rabbits, raccoons on a fairly frequent basis. But, it appears that we have already had substantial population reductions in those three mid-sized mammals that correlates with the rapid increase in python populations since 2000. One thing we want to do is kinda stagger the cars… There have been other studies if you go outside the park, you know north of the park or other areas where pythons are not as common or not present yet as far as we know… …you still find lots of possums and raccoons and those kinds of things. Technician: Oh, that is pretty. There you go, buddy. It is a Florida watersnake. They are a cottonmouth mimic. There you go, buddy. Well, it has kind of been a slow night. We found a few snakes: Cornsnakes, some watersnakes, and that kind of thing, but no pythons tonight, so far. Ahh, it is a beautiful night. We have got thunderstorms around so lots of lightning and lots of stars too. Yeah, we will see if we can find another python. So, it is a pretty nice night to be out here. I don’t want to say that I am too pessimistic, but pythons are going to be here long after we are here. Or, long after we are gone. I guess my hope is that we will learn enough about what has happened here with the Burmese pythons to hopefully prevent similar situations from occurring in the future. And, also through learning enough about their biology and ways they might be vulnerable to control, we might be able to control their populations in certain situations. But, in terms of widespread control across the landscape, it at least appears that pythons are here to stay.
My name is Larry Perez and I am a ranger here at Everglades National Park. And we are standing right now at the very border of Everglades. Off to our right hand side, we have got a fairly large stand of pine rockland that marcates the northern border of the park. Whereas down south here, we have got a canal area. And, this canal area sits right alongside the boundary line. This is important for the topic of discussion today as we talk about invasive species. As we know, typically, invasive species, biological invasions, are what we call a perimeter effects. Meaning they invade areas from outside. And so typically we will find that areas like this canal are perfect avenues/highways for introduction of all sorts of different taxa, nonnative taxa into these islands that we have preserved as national parks. As we have seen, invasive species and the problems they cause in the ecosystem are a real cause for concern for Everglades National Park. But, the problem does not necessarily stop at our borders. Instead, as much as we would like them to, invasive species scarcely respect the political boundaries that we lay out on the landscape. So, managing this problem in South Florida really mandates that we work across agency lines. Now, the National Park Service works in concert with the Everglades Cooperative Invasive Species Management Area, an agreement that allows us to pool our resources and our expertise and coordinate our efforts alongside other federal agencies, other state agencies, NGOs, universities, and tribal governments to really bring this fight to the forefront and keep ecosystems like those here in Everglades National Park healthy and free from invasive species. Managers currently right now are thinking that we are tracking about 350 species, that is plants and animals that have either proven themselves already or shown the potential to become invasive species just south of Lake Okeechobee, 350 species. And, the interesting thing about that number is that it never decreases. Instead, it always augments. Every single year, we get one or two new organisms in our ecosystem that we then have to account for indefinitely. And, of that 350 species that we find down here and that we monitor down here, we have got a pretty abysmal track record for those that we have been able to eradicate. Once an invasive species becomes established, it is incredibly difficult to physically remove them permanently from the ecosystem. We have a handful of success stories. But even those that we have been able to eradicate need constant monitoring after the fact. And so that number, that 350 continues to increase year after year. It is a treadmill that never really stops running and we are just trying to keep pace with it. Invasives in general in the country, there are certain definite hotspots. South Texas is one, Southern California is one, Hawaii, of course, is a big one. And, South Florida is as well. And that is for a variety of reasons. Most notably, our beautiful climate year-round keeps things pretty temperate and allows for a lot of different organisms to find a suitable home here. In addition to that, this is also a huge hub of commerce and of course our global traffic in all sorts of organisms, both live and dead, provide a variety of different pathways for these organisms to arrive here and establish in the first place. South Florida is home to approximately seven million people. And that presents tremendous problems in some ways. By definition, that means there are seven million potential vectors for new biological invasions to occur in South Florida. But, at the same time, those seven million people also present us with a pretty unique resource: Fourteen million eyes and ears that are constantly patrolling the landscape. That could be our first line of defense on finding and reporting new invasives. I encourage everyone as they go about their play in the natural world whether they are hunting, they are fishing, they are biking, they are birdwatching, or just relaxing on the beach to keep a wary eye open. And, if they see something out of the ordinary, report what they see. We have a few reporting avenues people can use: 1888-IveGot1 or online at www.IveGot1.org Filing a report early and easy is like making a call to 911. It sets into motion a team of emergency responders that can get out on the landscape, assess the situation and take management action if necessary to stop these populations before they become permanent problems in South Florida. Learn as much as you can before you buy, before you become a pet owner, before you buy your nursery plants. And, once you become one of those owners, understand how and why it is important to become a responsible steward of those plants and animals. Never, never, never release your animals in the wild! It is not healthy for them, it is not good potentially for the environment and it is illegal. Remember, don’t let it loose!
Click here for more video clips about nonnative species in Everglades National Park.
Did You Know?
Limestone is the porous, sedimentary rock you see in the Everglades. These rocks are made of calcium and contain fossils of sea life, evidence of ancient seas that once covered the area. The limestone aquifer under the Everglades acts as the principal water recharge area for all of south Florida.
