Show Title: Fiery Invaders
Producer: Erin Easterling
Time: 27:40
Show begins here:
>>>TODAY ON IMPACT, THESE FIERY INVADERS ARE AFFECTING MORE THAN JUST HUMANS.
---(I think it's under appreciated the impact that fire ants have on the native biota. Even if we ignore the vertebrate element, and just look at the invertebrate element, we're looking at a major disruption and a major change of ecological processes out there.)---
>>>RESEARCHERS ARE BRINGING IN NATIVE ENEMIES OF THE RED IMPORTED FIRE ANT TO HELP TO REDUCE IT'S DOMINATION.
---(If you keep putting 4 percent from one organism and 10 percent from another organism and 5 percent from another organism, you eventually stress the fire ant colonies. So that our native ants can compete.)-
>>>THIS IS IMPACT. A WEEKLY LOOK AT ISSUES AND ANSWERS THAT IMPACT OUR LIVES AND THE WORLD AROUND US. PRODUCED BY THE UNIVERSITY OF FLORIDA'S INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES.
>>>CENTURIES OF INTERNATIONAL TRADE HAVE INTRODUCED HUNDREDS OF EXOTIC PLANT AND ANIMAL SPECIES INTO THE UNITED STATES, INTENTIONALLY IN THE CASES OF FRUITS SUCH AS AVOCADOS AND PLANTAINS, AND ACCIDENTALLY WITH PESTS LIKE FORMOSAN TERMITES AND THE MOST MENACING OF ARRIVALS... SOLENOPSIS INVICTA, THE RED IMPORTED FIRE ANT. IT WAS DISCOVERED AT THE PORT OF MOBILE, ALABAMA IN THE EARLY 1940'S, THOUGHT TO HAVE BEEN BROUGHT IN ON SHIPS COMING FROM SOUTH AMERICA. SINCE THAT TIME, IT HAS INVADED MORE THAN 200 MILLION ACRES OF THE SOUTHERN UNITED STATES, AND IS CONTINUING TO SPREAD AT AN ESTIMATED RATE OF 30 MILES PER YEAR. DESPITE ATTEMPTS AT A WIDE SPREAD CHEMICAL ERADICATION, THE RED IMPORTED FIRE ANT REMAINS A SERIOUS URBAN AND AGRICULTURE PEST, CAUSING MILLIONS OF DOLLARS WORTH OF DAMAGE EACH YEAR. BUT MANY SCIENTISTS ARE CONCERNED THAT THEIR ECOLOGICAL IMPACT MAY BE THE MOST DEVASTATING.
>>>DAN WOJCIK - USDA/UF RESEARCH ENTOMOLOGIST: This is a very subtle form of attack or damage and it's not usually noticed until it's too late. People go out and say, "Oh, my God look at those fire ants, they just popped up over night." Well, 20, 30 mounds don't just pop up over night. It probably took ten years or more to get that way. The problem with fire ants, is that when you get about 9 to 10 mounds per acre, that's really the breaking point where the fire ants are starting to dominate the environment. There's enough of them out there, where they're starting to control things and be the dominant thing on baits and food sources or whatever.
>>>THE FIRE ANT SITUATION IN MANY SOUTHERN STATES HAS SURPASSED THAT BREAKING POINT TO WHERE A HUNDRED MOUNDS PER ACRE IS COMMON AND MANY SPECIES OF WILDLIFE ARE PAYING THE PRICE. ON THESE ISLANDS OFF THE COAST OF TEXAS, NESTING WATER BIRDS EXPERIENCED THE DESTRUCTIVE NATURE OF THE INVICTA SPECIES OF FIRE ANT. BIOLOGISTS DISCOVERED UP TO ONE HUNDRED PERCENT MORTALITY AMONG THE YOUNG BIRDS, WHICH WERE KILLED BY THE ANTS AS THEY HATCHED IN THEIR NESTS,
>>>JOE WHITEHEAD -NATIONAL AUDUBON SOCIETY: As soon as the young hatch, the ants attack them, and as they attack the first young that hatches, the old bird kicks everything out of the nest and tries a second clutch of eggs.
>>>IN 1989, EFFORTS TO SAVE THIS IMPORTANT NESTING HABITAT GOT TEXAS A & M ENTOMOLOGIST, DR. BART DREES INVOLVED. DREES TREATED HALF OF ONE ISLAND WITH LOGIC, A FIRE ANT BAIT CONTAINING AN INSECT GROWTH REGULATOR. HE LEFT HALF UNTREATED. THE RESULTS WERE ASTOUNDING. NESTING BIRDS MADE A THRIVING COMEBACK ON THE TREATED HALF OF THE ISLAND, WHILE THE SIDE WITH FIRE ANTS HAD LIMITED BIRD ACTIVITY.
>>>BART DREES - TEXAS A & M EXTENSION ENTOMOLOGIST: There are still a few ants out here, we didn't get a hundred percent control, but ants are no longer a problem.
>>>THE ISLAND WILL HAVE TO BE RETREATED ON AN ANNUAL BASIS TO MAINTAIN FIRE ANT CONTROL, BUT IT'S ESSENTIAL FOR PRESERVING THE FEW REMAINING NESTING SITES FOR THESE WATER BIRDS. RESEARCHERS ARE HOPING TO GET SIMILAR RESULTS THROUGH AERIAL TREATMENTS OF THIS PLANTATION NEAR TIFTON, GEORGIA, WHERE QUAIL POPULATIONS HAVE BEEN DECLINING OVER THE PAST DECADE. MANAGER HAROLD HOBBS THINKS FIRE ANTS MAY BE INVOLVED.
>>>HAROLD HOBBS - MANAGER - MOSSY DALE PLANTATION: I don't think they really know to the extreme what the problem is. The fire ant population has increased dramatically in the last 5 to 10 years. And at the same time, we've noticed that wildlife has been decreasing, so there's got to be something there between the two.
>>>STAN DIFFIE -UNIVERSITY OF GEORGIA RESEARCH ENTOMOLOGIST: The Texas researchers have documented that fire ants do kill some chicks, some baby quail. But in these situations, they usually have the quail in cages, and the ants come up and sting them. It's not a real natural habitat type of study, but we do know that if the opportunity was there, that the ants would sting the quail on the nest. There's also a couple of other things that might be affecting the quail population. One being, that the quail are real dependent on insects for their food source as soon as the chicks hatch. So the fire ants happen to enjoy insects also, so it may be that the fire ants are actually taking out or competing with the quail on the food.
>>>RESEARCHERS ARE INTERESTED IN THE EFFECTIVENESS OF AERIAL BAIT APPLICATIONS ON SUCH A LARGE SCALE BASIS AS THIS FIVE THOUSAND ACRE PLANTATION AND WHETHER OR NOT IT WILL IMPROVE THE QUAIL POPULATION.
>>>DIFFIE: Part of plantation we're treating twice a year, at the first of the year. Then we're going to go to a one year treatment, and then part of the plantation we're treating only once the first year, and we'll stay on that one year treatment. So we're also comparing those two application methods. And then of course, is to document whether the fire ants and the quail do have an interaction, because there's still some debate on whether the fire ants really do impact quail or not.
>>>FIRE ANTS ARE SUSPECTED TO HAVE A NEGATIVE EFFECT ON A VARIETY OF CREATURES, BUT DOCUMENTING THE PROBLEM IS IMPORTANT FOR DETERMINING WHETHER ANY TYPE OF CHEMICAL TREATMENT IS NECESSARY, ESPECIALLY IN ENVIRONMENTALLY SENSITIVE AREAS.
>>>DR. FRANKLIN PERCIVAL -UF WILDLIFE BIOLOGIST: The question is what kind of damage or what is a proportion of damage to the population, and once you answer that question, whether it is or is not a problem, then you would know whether to apply some kind of management strategy to deal with that problem.
>>>SUCH IS THE CASE WITH A FIELD STUDY TAKING PLACE IN THE FLORIDA KEYS. THIS RESEARCH TEAM SPONSORED BY THE FLORIDA GAME AND FRESHWATER FISH COMMISSION'S NON-GAME BUREAU, CONSISTS OF UNIVERSITY OF FLORIDA WILDLIFE BIOLOGIST CRAIG ALLEN, USDA RESEARCH ENTOMOLOGIST DAN WOJCIK, AND UF GRADUATE DR. ELIZABETH FORYS, NOW AN ENVIRONMENTAL SCIENCES PROFESSOR AT ECKERD COLLEGE.
>>>DR. ELIZABETH FORYS -ENVIRONMENTAL SCIENTIST-ECKERD COLLEGE: We're looking at the distribution and the abundance of the fire ants in basically four different habitats, the mangroves, transition zone habitat which occurs between mangroves and upper hardwood forests. The hardwood hammocks and also beach berms, which is a fairly rare habitat which we're also concerned about it. In addition we're also looking in the disturbed habitat types like roads.
>>>FORYS: Okay, this is transect number four, and we're trying to look at the distance that fire ants are foraging from this golf course, this highly disturbed area, into this lovely native hammock. I'm putting down terrestrial bait--this is a honey solution, made with honey, water, and dental wick to hold the honey in. I'm putting it down here so the ants can start foraging. This is a small ball of ground hamburger meat. Some ants prefer sweet things, other ants prefer fats. I'm placing these on either side of the flag so we can come back and pick these up in about an hour and see what ants are on them. Okay Craig, what are you doing?
>>>ALLEN: I'm placing the same two baits arboreally, into the native tree vegetation of this hammock. Part of our interest here is to see what ants are foraging into these trees, cause this was the former home of the Stock Island Tree Snail. And which of course, are primarily arboreal, and we'd like to know if fire ants and other ants are foraging into these trees.
---(Can you put one in that tree? That one ? Sure)---
>>>THE RESULTS OF THE TREE SAMPLES ARE ESPECIALLY IMPORTANT, BECAUSE THEY WILL HELP IN CHOOSING SITES FOR A RE-INTRODUCTION OF THE NEARLY EXTINCT STOCK ISLAND TREE SNAIL.
>>>ALLEN: The impact of red imported fire ants on native fauna, at least on a vertebrate level, remains controversial. Little research has been conducted. It's fairly well established that red imported fire ants have a major impact on invertebrate communities. What impact they're having on vertebrate communities is much less well known.
>>>THE FLORIDA KEYS IS HOME TO MANY WILDLIFE SPECIES THAT HAVE BECOME ENDANGERED BECAUSE OF HABITAT LOSS, BUT WHEN YOU ADD ON TOP OF THAT, HAVING TO DEFEND THICSELVES AGAINST FIRE ANTS, THEY ARE EVEN MORE AT RISK. THE LOWER KEYS MARSH RABBIT OFTEN BEARS ITS YOUNG WITHIN PATCHES OF DENSE GRASSES, WHERE THEY CAN'T BE SEEN BY MOST PREDATORS. FIRE ANTS ARE A DANGEROUS EXCEPTION.
>>>FORYS: When rabbits are born they are very altricial, that is they're born with their eyes closed and they can't really move, generally, and barely furred. At this point, if fire ants move in, young rabbits are born covered in mucous and the fire ants can sense that. They can move in, they can actually bite, attack and then eventually eat the young rabbit. Mother rabbits can't pick up the young rabbits by the scruff of the neck and move them away. Young rabbits are very susceptible. And rabbits do nest on the ground in the keys not in holes, so they are very, right where the fire ant is.
>>>SAMPLING IN THE MARSH RABBIT HABITAT, REVEALED WITHIN MINUTES THAT THE RED IMPORTED FIRE ANT WAS THE DOMINANT ANT IN THE AREA.
>>>ALLEN: I believe that the invasion process in ongoing down here and they've certainly not filled in all available habitats. There's also native and a large number of exotic species in the keys that are going to provide some competitive forces to keep the fire ants out or at least slow down the invasion. As we've expected, we've found fire ants in disturbed habitats. Surprisingly, we've found fire ants in the interior of some pretty pristine hammocks.
>>>ALLEN SAYS THAT WITHIN THE PAST DECADE, A SHIFT IN FIRE ANT BIOLOGY FROM SINGLE QUEEN TO MULTIPLE QUEEN MOUNDS MAY BE CONTRIBUTING TO THEIR INCREASING IMPACT ON WILDLIFE.
>>>ALLEN: Earlier research from the 60's seemed to conclude, although it was variable, that there was little impact but fire ants on wildlife. Research I conducted in Texas and others have conducted as well has indicated recently that there's a big problem. Densities of fire ants were limited by interest-specific competition. The mounds are territorial, with single queens in the mounds, and density is generally less that 40 mounds an acre. Now we see here and there multiple queen mounds that lose territoriality and may have occur at extremely high densities, greater that 1,000 mounds an acre, although that's unusual. But certainly always over 100 mounds an acre. And when you have 100 mounds an acre of an ant that's predacious, and a very efficient forager, and does impact native communities, you've got to be concerned.
>>>BIOLOGIST TOM WILMERS, EXPERIENCED FIRE ANTS IN THE MARQUESAS KEYS, A PRISTINE WILDERNESS 25 MILES OFF THE COAST OF KEY WEST.
>>>TOM WILMERS - U.S. FISH AND WILDLIFE BIOLOGIST -NATIONAL KEY DEER WILDLIFE REFUGE: The thing that really turned me around was to find a nest of sea turtles, and in this case endangered green turtles and a swarm of fire ants just covering the babies that were coming out of the eggs. So in that particular instance, we saved a lot of those babies, but some of them perished, their eyes had been eaten. So, right away, being that we only have four adult green female breeding, green turtles breeding in the entire refuge, there was cause for concern there. So that was really my introduction to the severity of the problem, the fact that really the essence of the wilderness was no longer wilderness in the truest sense, it had been breached by a lot more than exotic pest plants which are very few down there, but instead by a potential predator of the sea turtles.
>>>DESPITE HIS CONCERNS, WILMERS IS WEARY OF USING CHEMICAL FIRE ANT TREATMENTS IN ENDANGERED WILDLIFE HABITATS.
>>>WILMERS: We need to get some more base line data on what the extent of the problem is. That's very important before we start taking any action with pesticides or widespread applications of anything. We need to really document that it's doing what we surmise that it is doing. My guess is that we're in for some real rough rides here with some of these species.
>>>IN A LABORATORY SETTING, RESEARCHERS DOCUMENTED THE THREAT OF FIRE ANTS TO HATCHING SEA TURTLES BY USING NON-ENDANGERED SPECIES AS SURROGATES. CLUTCHES OF FRESHWATER TURTLE EGGS WERE PLACED IN CLOSE PROXIMITY TO FIRE ANT NESTS. THE ANTS WERE GIVEN A FOOD SOURCE AND MINIMAL INTERACTION WAS OBSERVED, UNTIL THE TURTLES BEGAN BREAKING OUT OF THEIR SHELLS. IN SOME CASES THE FIRST HATCHLINGS ESCAPED TO SAFETY IN A POOL OF WATER. BUT WITH MOST OF THE EMERGING TURTLES, THE FIRE ANTS EVENTUALLY OVERWHELMED THEM. SOME DIDN'T EVEN MAKE IT OUT OF THEIR SHELLS. THIS EXPERIMENT DEMONSTRATED THE INDISCRIMINATE FEEDING BEHAVIOR OF FIRE ANTS.
>>>WOJCIK: The fire ant is the biggest, toughest, meanest S.O.B. on the block. There's nothing really in North America that is anywhere like that. You have some native fire ant species, but even they don't have the populations or the numbers in colonies to equal the imported species.
>>>THE RAPID SPREAD OF THE RED IMPORTED FIRE ANTS THROUGHOUT FLORIDA IS ATTRIBUTED TO THEIR MATING FLIGHTS. WINGED REPRODUCTIVES TRAVEL TO DISTURBED AREAS LIKE ROADSIDES OR HOUSING DEVELOPMENTS, WHERE THEY ARE OFTEN ABLE TO START A NEW COLONY WITHOUT CHALLENGE.
>>>WOJCIK: People who have worked out on oil rigs in the Gulf of Mexico sixty, seventy miles have collected fire ants out there. Queens after a mating flight. So, the distance they will fly depends on where they are and how far the wind really takes them.
>>>DAN WOJCIK HAS BEEN STUDYING FIRE ANTS FOR MORE THAN 25 YEARS AND DURING THAT TIME, HE HAS TRACED THEIR MOVEMENT INTO THE CITY OF GAINESVILLE, FLORIDA. SINCE 1972, THE RED IMPORTED FIRE ANT POPULATION HAS GROWN FROM NON-EXISTENCE TO DOMINANCE, ACCOUNTING FOR MORE THAN SIXTY PERCENT OF THE ALL ANTS IN THE AREA. OTHER ANT SPECIES, INCLUDING A NATIVE FIRE ANT, SOLENOPSIS GEMINATA, ARE SLOWLY BEING WIPED OUT BY THE AGGRESSIVE INVICTA SPECIES. HOWEVER UNPLEASANT, RESIDENTS HAVE LEARNED TO ADAPT TO LIFE WITH THE RED IMPORTED FIRE ANT.
>>>WOJCIK: What's happening is the areas that were infested first, the people have learned to deal with them or have learned to live with them, shall we say. You get a lot of complaints from people when fire ants first move into an area and say, the first 15 to 20 years that you're there, then after a while, everyone sort of learns it. And like the old time southerners learned to stay out of geminata nests, well the new ones are learning to stay out of invicta nests. The problem is that we have a state where tremendous numbers of visitors come in that are naive about fire ants in general, and a lot of people moving here that are naive about fire ants and they have to learn. And often they learn the hard way. You can get stung thousands of times which can be extremely uncomfortable, which I can certainly attest to.
>>>UNFORTUNATELY, FIVE PERCENT OF THE POPULATION CAN HAVE EXTREMELY SERIOUS REACTIONS TO FIRE ANT STINGS.
>>>DR. JAMES GALLAGHER - CHIEF - SHANDS CRITICAL CARE CENTER: Once one has been bitten, then the situation is a set-up for that second bite for the anaphylactic type reaction to occur. A true anaphylactic reaction to a fire ant sting is a life-threatening situation if it's not immediately treated in a hospital or by someone who has all the equipment on hand. It can certainly be fatal in a very short period of time.
>>>THE NEED TO REDUCE POPULATIONS OF THE RED IMPORTED FIRE ANT IS OBVIOUS, BUT EXPERTS STILL DON'T HAVE ALL THE ANSWERS TO HELP ACHIEVE THIS GOAL.
>>>DR. JERRY STIMAC - UF PROFESSOR OF INSECT ECOLOGY: It was imported from an area that has a complex of natural enemies. But we imported it without those natural enemies, so what holds it in check in it's homeland is absent here. So we're trying to bring one of these elements from the homeland and to accentuate its activity here, and hopefully we'll be able to get the fire ant under control.
>>>PART OF STIMAC'S BIO-CONTROL WORK IS WITH A FUNGUS CALLED BEAUVERIA BASSIANA. IT WAS FIRST FOUND IN FIRE ANT NESTS IN BRAZIL.
>>>STIMAC: We discovered that the fungus actually cycles there naturally, and acts as a control mechanism. So we then isolated the spores of the fungus, took them into the laboratory at the University of Sao Paulo in Brazil, and with my colleague, Dr. Sergio Alves, we learned how to culture the fungus, we purified it and then brought the fungus back to the United States to study it in quarantine.
>>>DISCOVERING THE FUNGUS WAS ONLY HALF THE BATTLE, STIMAC'S NEXT CHALLENGE WAS TO FIND A WAY TO INFECT AN ENTIRE COLONY.
>>>STIMAC: As you can see from this nest, the ants only form the top part of their nest above the ground, as I break this open, you'll see that the ants have a series of galleries and tunnels underneath the soil. And this is where they spend most of their life. So, because the ant gets infected by making contact with the fungus, not by eating it, then we have to have a way to be able to deliver the fungal spores which are the infective units to the ants down in the nest.
>>>SO STIMAC'S LAB DEVELOPED A BAIT THAT THE ANTS WOULD ACTIVELY FORAGE. THE ANTS DISTRIBUTE THE FUNGAL SPORES WITHIN THE COLONY THROUGH CONTACT WITH THE BAIT AND OTHER ANTS.
>>>STIMAC: When the spore touches the ant, it adheres to the exoskeleton, or the outside surface of the ant, it then forms a germ tube and penetrates the ant's body, goes inside, the disease grows in the ant's blood, or hemolymph, and then after it kills the ant, the germ tube forms and bursts outside of the ant, grows over the body's surface and grows millions of additional spores which serve as new, infective units.
>>>SEVERAL FIELD TESTS WITH THE FUNGUS IN HEAVILY INFESTED PASTURES, REDUCED THE FIRE ANT POPULATION BY UP TO EIGHTY PERCENT AND DECREASED THE NUMBER OF MOUNDS BY UP TO FIFTY PERCENT. STIMAC HOPES TO GET THE FUNGUS REGISTERED AS A COMMERCIAL PRODUCT, SO IT CAN BE USED AS A BAIT TREATMENT SOMETIME IN THE NEAR FUTURE. HOWEVER THIS WOULD STILL ONLY BE ONE WEAPON IN THE ARSENAL NEEDED TO CONTROL THE RED IMPORTED FIRE ANT.
>>>STIMAC: People need to understand is that we will never eradicate this species. And that is not the goal of a biological control program. The goal of a biological control program is to reduce the population to a tolerable level, but maintain enough to be able to maintain the biological agent.
>>>THE UNIVERSITY OF FLORIDA HAS AN EXCELLENT WORKING RELATIONSHIP WITH THE USDA'S AGRICULTURAL RESEARCH SERVICE IN GAINESVILLE. MANY USDA RESEARCHERS ARE ADJUNCT UF FACULTY AND ARE ACADEMIC ADVISORS TO UF STUDENTS. USDA RESEARCHERS ARE ALSO TESTING SEVERAL BIOLOGICAL CONTROL POSSIBILITIES FOR FIRE ANTS. DR. DAVID WILLIAMS IS CURRENTLY WORKING WITH A PARASITIC ANT ORIGINATING IN ARGENTINA AND BRAZIL.
>>>DR. DAVID WILLIAMS -USDA/UF RESEARCH ENTOMOLOGIST: Almost all the fire ant colonies would not allow any strange organism or strange animal to enter the colony. But there are some insects that can mimic the colony's chemical defense--chemical communications system. And in this case, the-this Labochina dogeri mimics the queen of the fire ant colony, and also the brood of the fire ant colony. So that the workers in the fire ant, rather than killing them, would actually accept them and treat them as if they belonged in the colony.
>>>THE PARASITIC ANTS GRAB ON TO THE FIRE ANT QUEEN AND ARE FED BY THE WORKER ANTS AT THE QUEEN'S EXPENSE CAUSING HER TO SLOWLY DIE OFF.
>>>WILLIAMS: As it increases in size and numbers than the fire ant colony decreases in size, and because it does impact on fire ant colonies, the colony slowly dies out. Now it has to move to other fire ant colonies which it does. It moves over to other colonies. We're not quite sure how it moves from one colony to another and we're studying that. In South America we figured it's probably about 4 to 7 percent in all the colonies have Labochina . Although that's a low percentage, if you keep putting 4 percent from one organism and 10 % from another organism and 5 % from another organism, you eventually stress the fire ant colonies. So that our native ants can compete.
>>>WILLIAMS IS ALSO STUDYING A MICROSPORIDIUM PATHOGEN THAT CAUSES A DEADLY DISEASE ONLY IN FIRE ANTS. IT COMES FROM THE FIRE ANT'S HOMELAND AND WAS RECENTLY DISCOVERED INFECTING FIRE ANT COLONIES IN THE UNITED STATES.
>>>WILLIAMS: We have gone out into the field in Florida, and collected infected fire ant colonies, and non-infected fire ant colonies, brought them back to the lab, and held them under the exact same conditions and fed them the same things, and the non-infected colonies have just exploded in size. Huge numbers of 500,000 workers, whereas the infected colonies are down to about 100 workers or less, and they are dying out in a matter of 6 months. That's how great this pathogen is on fire ants.
>>>THE NEXT STEPS ARE TO LEARN HOW TO MASS PRODUCE THIS PATHOGEN AND FIGURE OUT HOW TO USE IT TO INFECT FIRE ANT COLONIES WITH IT FOR A POSSIBLE WIDE SCALE DISTRIBUTION. ANOTHER POTENTIAL FOR CONTROL ARE THESE TINY FLIES BROUGHT FROM BRAZIL IN 1996 BY USDA ENTOMOLOGIST, DR. SANFORD PORTER. IN NATURE, WHEN A FIRE ANT COLONY IS DISTURBED, THE ANTS PREPARE FOR BATTLE. NOT SO, WHEN THESE FLIES ARE PRESENT.
>>>PORTER: The ants are deathly afraid of these flies, they recognize them as a very important natural enemy. So whenever the flies come, the ants will freeze. They stop foraging, they stop whatever they're doing and try to hide from the flies.
>>>WHILE A GROUP OF FIRE ANTS IS ON THE DEFENSIVE, THESE PARASITIC FLIES BEGIN TO ATTACK.
>>>PORTER: They begin to hovering about 2 to 3 millimeters above the fire ants. And the females are searching for larger workers, and when they find the larger worker, they dart in and in about 1/10 of a second, they inject a hypodermic needle, ova-positor, they inject an egg into the ant, the ant is stunned, like it's been stuck amid-side, and indeed it has.
>>>THIS IS AN ELECTRON MICROSCOPE PHOTOGRAPH OF THE FLY'S PITCHFORK-LIKE OVIPOSITOR, USED TO LAY EGGS. THE LARVAE THAT HATCHES FROM AN EGG FEEDS ON THE HEAD OF IT'S HOST, EVENTUALLY CAUSING IT TO FALL OFF. THE PUPAL STAGE IS COMPLETED INSIDE THE ANT'S HEAD AND SOON AFTERWARD, AN EMERGING ADULT FLIES FROM THE FIRE ANT'S MOUTH.
>>>PORTER: We're hoping that if we bring in the right combination of these bio-control agents, that we can shift the ecological balance just enough that the native ants can compete with the imported ants on an even basis. And then the balance will tilt, and then the number of fire ants will hopefully drop to levels that are similar to what we find in South America.
>>>EXTENSIVE TESTS HAVE DEMONSTRATED THAT THESE FLIES WILL ONLY ATTACK IMPORTED FIRE ANTS, NOT ANTS NATIVE TO THE U.S. DR. PORTER IS PLANNING A TRIAL RELEASE OF THESE PARASITIC FLIES IN FLORIDA SOMETIME THIS SPRING. IN THE MEANTIME, PEOPLE WILL HAVE TO RELY ON CONTROL METHODS THAT ARE CURRENTLY AVAILABLE. WHEN IS COMES TO GETTING RID OF FIRE ANTS, RESIDENTS OFTEN RESORT TO DESPERATE MEASURES.
---(Use fire on fire ants)---
---(When you see the mound, then you go sprinkle some Amdro on it and then they carry it back down into the nest, and it's the only thing that kills them, because I kill anything that walks or crawls, other than the lizards. I'm fond of the lizards.)---
---(Sometimes I step on them)---
>>>STIMAC: Some people have called me and asked if they could eliminate the nest by using flame throwers.
>>>WILLIAMS: Everything from citrus peels to dead cockroaches ...
>>>DR. PHIL KOEHLER - UF URBAN ENTOMOLOGIST: Some of the crazy ones are that you can put instant grits on a mound and the ants will eat the grits and then explode from the grits expanding in their stomachs. Fire ants do not ingest, do not swallow anything but liquids, so they couldn't get grits down into their stomachs.
>>>WHEN CHOOSING A FIRE ANT TREATMENT, READING THE LABEL AND FOLLOWING DIRECTIONS ARE THE MOST IMPORTANT THINGS A PERSON CAN DO.
>>>KOEHLER: Many people when they come to the store, they are very confused about what the can use for ant control. There are products with ants on the label, and there are products that are specifically for the control of fire ants. There are basically three kinds of products on the shelf for fire ant control. First of all, there are fire ant baits, there are fire ant granules and then there are concentrates that you would pour on a fire ant mound that you would call a drench. The granules and the drenches work very much alike. They have very fast acting poisons. When an insecticide is released on the mound, the ants are killed from contact. The problem with that kind of approach, is that if you have a hot sunny day, and the ants are located maybe several feet down underneath the ground, the insecticide doesn't reach them. The baits are very good at times when ants are foraging. The ants go out and out, pick up the baits, take them back to the colony. They work very slow, in being passed from ant to ant, and eventually to the queen and then the colony eventually dies off several weeks later.
>>>THE MAIN PROBLEM WITH CHEMICAL FIRE ANT TREATMENTS IS THAT NOTHING OFFERS PERMANENT CONTROL. REGULAR MATING FLIGHTS CAN BRING NEW COLONIES BACK INTO A YARD THAT HAS ALREADY BEEN TREATED. SO RIGHT NOW, FIRE ANTS ARE WINNING THE RACE TO BECOME THE DOMINANT ANT IN THE SOUTHERN UNITED STATES. SCIENTISTS WILL KEEP SEARCHING FOR THE ENEMIES NEEDED TO FIGHT AGAINST THESE FIERY INVADERS, WITH HOPES THAT SOMEDAY THE RED IMPORTED FIRE ANT WILL EXIST AT TOLERABLE LEVELS THAT ALL OF US CAN LIVE WITH.
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>>>IMPACT, A WEEKLY LOOK AT ISSUES AND ANSWERS THAT IMPACT OUR LIVES AND THE WORLD AROUND US. IT'S PRODUCED BY THE UNIVERSITY OF FLORIDA'S INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES.
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