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This is a transcript from a video about nonnative flora and fauna found in the South Florida ecosystem and the threats they pose on the Everglades (ENP). This week on Waterways, Invasive Exotics of South Florida. Dumeril’s boa, Argentine boa, Cockatoos! These animals are just a few of the pets handed over to the Florida Fish and Wildlife Conservation Commission at Pet Amnesty Day. The list is long; and the potential danger to the south Florida ecosystem from some of these invaders is grave. One particular invasive exotic animal has captured many media headlines: the Burmese python. A native to Asia, the Burmese python is one of the six largest snakes in the world, but it’s just one of an estimated three to four hundred different invasive plant and animal species in south Florida—and that’s just south of Lake Okeechobee. Some of these organisms are known to be invasive; while others have proven to be invasive elsewhere, but have not yet reached critical numbers here. But how did these snakes get here from Asia? One theory postulates that pythons were introduced in 1992 when Hurricane Andrew tore through Homestead, Florida, a town near the southeastern boundary of Everglades National Park. The storm flattened a flimsy storage facility for imported snakes and other reptiles resulting in a release of snakes into the surrounding ecosystem. But a more likely theory is that Burmese pythons in the Everglades are a cumulative effect of multiple pet owners releasing their snakes into the wild. It became obvious really early on that the reason we were having problems with constrictors out here in Everglades National Park and elsewhere in south Florida was because people were, perhaps, making poor, uninformed decisions about purchasing these snakes while they were small and then in a year when that snake got out to seven or eight feet or two years when it hits double digits they had no alternatives. To be honest with you that question of how these animals arrived here in the first place is somewhat moot. We know that they were here for one purpose and one purpose only: to be eventually sold into the pet trade at one time or another. These are animals that are brought in here specifically for ownership, for pet ownership. In south Florida, Burmese pythons are considered an invasive exotic species. Exotic species are non-native plants and animals introduced intentionally or accidentally to an area through human activity. It is crucial to draw a distinction between an exotic species and an invasive exotic species. An organism can be exotic and not be invasive. An exotic organism is not necessarily harmful to an ecosystem; an invasive exotic can be disastrous. Fortunately for us, the vast majority of species that are introduced into an area, exotic species, don’t turn out to be invasive. Invasive species are those that go out of control; that move beyond cultivation and get into areas where we don’t intend them to be and begin reproducing on the landscape. Invasive exotic species are able to dominate an ecosystem because they often have no or few predators. In their new environment, there are no mechanisms to keep the population in check. Invasive exotics have not evolved to live in the delicate balance of their new surroundings. Thus, some invasive species can decimate the flora and fauna of an entire ecosystem. The first line of attack to keep out invaders? Prevention. Biologists at Everglades National Park knew that eradicating ALL the pythons within the park boundary would not solve the problem; they still needed to eliminate the source. So in 2006, the Don’t Let It Loose campaign was developed. Through publications, school posters, PSAs, billboards and presentations, Everglades National Park made a concerted effort to reach out to the community and remind them of the danger posed by invasive plants and animals. As part of the Don’t Let It Loose campaign, resource managers decided to give people a way to get rid of their exotic pets in ways that did not hurt the environment. And starting in 2008, the Park partnered with The Florida Fish and Wildlife Conservation Commission and actually presented the first non-native pet amnesty day here in south Florida at Miami Metro Zoo. And it was a phenomenally successful event where we offered folks the opportunity to come out with their animals and no questions asked surrender their non-domestic pets with us. A wide range of animals appear at Amnesty Day events. Resource managers in Everglades National Park also knew that they could not control python populations or other invasive exotics if they could not reach beyond their borders. So in 2006, the Everglades Cooperative Invasive Species Management Area, or Everglades CISMA, was created. This interagency working group operates across administrative boundaries to better manage invasive species in south Florida. We’ve been dealing with some of these organisms for literally a century or more that they’ve been here in south Florida and have been actively managing them for decades. And they’re species that you’re familiar with; things like melaleuca, Brazilian pepper, Australian pine. And the reason we focus so much attention on these plant species is that they are capable of consuming entire acreages. While invasive exotic animals, like the python, get most of the media attention, invasive exotic plants could pose an even greater threat. Large areas of the Everglades that were once dominated by melaleuca, a native of Australia, are now at maintenance levels. Despite these successes, there are many areas of south Florida severely impacted by invasive exotic plants. Brazilian pepper, imported in the 1800s, now covers more than 700,000 acres in Florida and Old World Climbing Fern which can smother entire forests. It's unlikely these species will ever fully be eradicated. We have five success stories where our management actions have deliberately resulted in the eradication of a species from the south Florida landscape. And I’ll tell you right now, again this depends on your definition of eradication, it’s the black-tailed jack rabbit; the red-bellied piranha; the giant Gambian pouch rat; the giant African snail; really I don’t think we should importing anything with the word ‘giant’ in its name; but that’s just me. And, most recently a bird called the sacred ibis. Upon closer look at those five successful eradication efforts, there is one common thread: resource managers learned about those invasions early on; and they took action immediately. This is Tony Pernas. Tony works for Everglades National Park and one of his jobs is to track an invasive exotic lizard called the Tegu. Well we basically, what we want to find out about the tegus is their movements in the Florida City area and whether they’re moving into natural areas and what habitats they’re using. We just want to find out as much information as we can about the tegus so we can hopefully effectively manage their population. Tony and his team have caught tegus within the boundaries of Everglades National Park. Today, they are collecting images from their field cameras in areas surrounding the Park. So as part of an effort to assess the population of Argentine black and white tegus, we have a system or a network of camera monitoring traps and this is one of them that we check periodically to see if any tegus are present in the area. These cameras are triggered by motion and infrared sensors. Using chicken eggs as bait, the researchers have had a lot of success capturing images of tegus. Really quickly, we’re downloading the data card and see if we had any activity. This is a good thing about these cameras, because you don’t actually have to be there. You can set up a network of these cameras with bait so you get a record of anything that’s visiting this site, twenty-four hours a day. So why are all of these exotic species showing up in south Florida in the first place? We are a biological hot spot for these invasions. We’re up there with southern California and Hawaii for being just a hub of having these things introduced; largely because of the large amount of commerce in the area as well as the favorable climate that hosts these organisms. So we’ve had a lot of things introduced, but we’ve been lucky so far that we haven’t really had that one cataclysmic species. That was until very recently. MUSIC Beautiful, bold, maroon and white striped patterns across the body; ornate spires jutting in all directions, regal and striking with long pectoral fins and prominent dorsal spines: the lionfish. So beautiful that people buy them for their home aquariums; however, these beautiful fish now threaten the coral reefs of the Florida Keys. Lionfish are an Indo-Pacific reef fish and the Florida Keys are far away from their native range. Today, however, they are established from North Carolina throughout the Caribbean, and are now invading the Gulf of Mexico. And if you look at the time in which they have achieved that geographic range, it is astounding. We first saw lionfish off the coast of North Carolina in 2000. That marked the beginning of the establishment of lionfish. And the Bahamas are probably the most heavily invaded area in the Caribbean right now. And the density of lionfish in the Bahamas now are among the highest we know of anywhere in the world. We’re talking in excess of four hundred lionfish per hectare. That’s a lot of lionfish. They are becoming one of the biggest predatory fish on the reef. A big question everyone has is how did this invasion start? And of course there are a number of different potential pathways; ballast water from ships; natural migration is highly unlikely seeing that it is a long way to the Indo-Pacific and there have been no populations established along the way. But aquarium releases are another pathway. And that’s the most likely pathway that these fish were introduced from. Releases usually happen because it gets too big for the aquarium; it costs too much to keep feeding it; the person holding the fish feels sorry for the fish because it’s a pet and they want to release it- sort of the ‘Nemo’ syndrome. Or they’re moving and they don’t want to kill the fish or give it back to the pet store. Once introduced to the Atlantic, lionfish spread rapidly. They have a superior ability to colonize, and their life history creates a perfect storm of propagation, starting with the larvae. The long larval duration period of lionfish allows them to basically be distributed anywhere in their invaded range. So lionfish spawned in the Caribbean for example can end up off of North Carolina waters because of that larval duration. And so that is one of the many characteristics of lionfish that has facilitated or allowed this invasion to take hold. Another reason lionfish have been able to colonize so effectively, is due to the lack of competition for reef space and food. For years, top-level predators that inhabit the Florida Keys reefs have been over-fished—this reduction of native species has left a vacant niche. And in the case of invasive species, we see classically that invaders can come in and occupy vacant niches in new environments and can cause real problems to those environments. Such is the case with lionfish and the real concern is that if lionfish come in and take over that niche then how will that impact our stock rebuilding efforts for the snapper grouper complex? And how will that impact the structure of the reef communities? Lionfish competing for a food source with economically important species is bad; lionfish eating economically important species is worse. Biologists have found Nassau Grouper, yellowtail snapper, and vermillion snapper in the stomachs of lionfish in the Atlantic. We’re concerned that as lionfish continue to prey upon these species and prey down the numbers, because lionfish are one of the most dominant reef fishes now in some coral reef environments like in the Bahamas, that they will then go to some of the juveniles of economically important species. And that’s a real concern because increase predation pressure on those economically important species could in fact hamper stock rebuilding efforts. Lionfish also consume ecologically important species, such as parrotfish and wrasses; fish that graze the reef and eat algae, which competes with coral. Lad Akins from Reef Environmental Education Foundation sees signs in the Bahamas that alarm him. They’re becoming one of the most abundant predatory fish on the reef. And the impacts that those fish are having are being seen as simply unsustainable. They’re consuming native reef fish at a rate far faster than the native fish can recover. The first confirmed lionfish sighting in the Florida Keys National Marine Sanctuary was in January 2009, and resource managers in the Keys were ready for it. NOAA had been working on a lionfish invasion response program for nearly a decade. The program’s key element: engaging the public. Months before the first confirmed sighting, sanctuary staff and their partners at Reef Environmental Education Foundation and Mote Marine Lab educated the public on how to identify the fish and who to call to report a sighting. When the first lionfish sighting report came in January 2009, a response team from Reef Environmental Education Foundation, also known as REEF, was mobilized and caught the culprit the very next morning. Sanctuary managers even issued the fish a mock citation for trespassing. As reef managers anticipated, lionfish populations spread quickly throughout the Florida Keys reef tract. Six months after the first sanctuary sighting, the first lionfish was caught just south of Miami, in Biscayne National Park, the largest marine park in the National Park System. So far, park staff have caught nearly 900. Invasive exotics are a problem in Biscayne National Park. The lionfish represents the first case of a marine invasive that we’ve been concerned about. Before our main issues had been with plants, so this is a whole new realm for us. As the invasion progressed, so too did the response. In 2009, sanctuary managers and REEF began training dive-shop personnel, marine-life collectors and researchers on how to safely collect lionfish. Since 2009, more than 500 divers have been trained to safely handle and collect lionfish in the Florida Keys. Lionfish are very quick over short distances, which make them a challenge to catch. Many people say, well what is the best way to collect a lionfish? And certainly spearing a lionfish is an option where spearing is allowed. But because the fish are so quick and have such fast reflexes, it’s easy to miss with a spear; even on a very close approach. The lionfish just moves at the very last second and you miss. And once the spear goes flying by, the lionfish gets the idea- when I see a person, they are trying to get me and I’m going to leave. And it makes subsequent collection efforts for that fish very difficult. Lionfish hunters have had much more success using nets. Using two nets, the diver can gingerly maneuver the nets around the lionfish. That doesn’t mean don’t use a spear, in fact on some of the bigger fish that may be a better option. But especially for small fish and a higher success rate, the nets seem to work very, very well. Those who hunt lionfish need to exercise caution. It is highly recommended that anyone who handles lionfish receive training on how to do it safely. Although the spines on a lionfish are not lethal, reactions to the stings can vary and usually include pain and swelling. If you’re stung, the best treatment is to immerse the wound in hot, but not scalding water. A lionfish is venomous. Just the spines contain the venom. You don’t eat the spines and therefore you are not, you are not going to be exposed to any of the venom. We eat the flesh, we eat the filets and they are not poisonous in any way. If you haven’t been trained or you don’t feel comfortable capturing a lionfish, the next best thing is to mark down the location where you saw it. The good news about that information is that if we get a report, it’s very likely that fish is going to be in the same spot when we go out to respond. So we can have high confidence in being able to respond in our early detection and rapid response efforts. We have been looking at what’s going to keep them in check here. What keeps them in check in their native range; what keeps them in check in their invaded range. And what we’re finding is that few things eat lionfish. In feeding trials conducted fin a lab, Morris tested whether or not native groupers would feed upon lionfish. In almost every situation, the native groupers fed upon alternative prey when given a choice, avoiding lionfish even during extreme starvation. Not to say that nothing eats lionfish, but we’re finding that few things eat lionfish. That again is one of the characteristics in their life history that has probably allowed them to become so invasive. However, there is one predator at the top of the food chain that could help manage lionfish populations, us. Lionfish is actually a very good eating fish; and REEF and NOAA’s Eat Lionfish campaign are working to create demand for lionfish. Restaurants in the Florida Keys have already begun serving lionfish, and REEF has published The Lionfish Cookbook: The Caribbean’s New Delicacy. Encouraging restaurants to serve them on the menu is important. And trying lionfish; it is a great eating fish. It’s kind of a cross between on hogfish and a grouper; very delicate, light flavored meat. So encouraging that and eating lionfish when it is available. It’s going to help create that market demand. Lionfish are here to stay, but resource managers are working hard to keep their numbers in check using some novel control strategies. In 2010, REEF and the Florida Keys National Marine Sanctuary hosted three lionfish derbies in which 660 lionfish were removed from sanctuary waters by dive teams competing for more than $10,000 in cash and prizes. More than 1200 lionfish were removed in two derbies in 2011 and more round-ups are being planned. Researchers collected samples from lionfish caught at the derbies to learn more about lionfish genetics, growth and impacts to native marine life, and tournament attendees sampled lionfish dishes. These events, along with diver involvement and lionfish consumption are important strategies in keeping lionfish under control. If the lionfish populations are going to be kept in check, the National Parks and the Marine Sanctuary need your help. To report a lionfish sighting or capture, take note of the location and submit a report to www.reef.org. I don’t want to minimize that fact that people are going to be the controlling factor of this. And if anyone wants to get involved and take part, they are really going to be doing a lot to help protect the oceans. Minimizing and managing lionfish populations is also dependent upon eliminating the historic source of lionfish introductions into the wild: people. The best thing to do if you have an unwanted fish is first contact the store at which you purchased the fish and see if they’re willing to take it back; and many are. If that’s not feasible, you may have other aquarium owners that may be interested in your fish. And finally if you just can’t do anything else, the most humane way to deal with the fish is probably just freeze it. Put it in a container, put ice in there, the temperature will cool off very quickly and the fish will just kind of shut down and end up passing away. You certainly don’t want to release it into the wild. The Keys is an especially sensitive environment. One, because of the status of coral reef environments in general; the stressors that are happening in coral reef environments, can in fact compound the stress induced by a lionfish invasion. And how these stressors all work together and impact the fish community and the coral community is really unknown. And we’re sort of getting out on virgin territory in terms of assessing or predicting or forecasting the impact of an invader like this. Each year, at least two or three new “invaders” appear in south Florida that don’t belong here. Will these exotic species become invasive? What will their impact be on the south Florida ecosystem? When we do have a new introduction, we count on those five to six million people out here to be our twelve million eyes and ears; our first line of defense in letting us know when new introductions happen. Recently, the Everglades Cooperative Invasive Species Management Area, launched a new campaign called I’ve Got One. Anybody in south Florida who sees a plant or animal that they don’t think is quite right—it looks different, sounds different, they think it’s an invasive species, they can report it, either by calling 1-888-I-GOT-ONE or online at www.Ivegot1.org. Making that report sets into motion a team of responders, just like a call to 911. A group of individuals goes out, verifies that report and if management actions mandate it, we can act quickly, interagency; to go and quell that population before it expands out of control. And that’s the key— acting quickly before a population gets out of control. But the local, state and federal land management agencies can’t do it without your help. Here’s what you can do: first and foremost— be a responsible pet owner. If you have an exotic pet you can no longer take care of, go to myfwc.com/nonnatives for dates and locations of upcoming non-native pet amnesty days. Second, learn to identify what’s native and what’s not. If you spot a plant or animal that shouldn’t be here, like the elusive Burmese python, report it at www.IvegotOne.org. To report a lionfish sighting or capture, go to www.reef.org. In the end, the natives will thank you. MUSIC
Contributed by Abigayle Hewett