Ants. We’ve all seen them and been annoyed by them at some point in our lives. Whether spoiling a nice picnic or invading our kitchen countertops, there are many different types of ants in Florida. Ants are the #1 structural urban pest problem in the United States accounting for billions of dollars per year spent in population control, and losses from agricultural damage. Mr. Pest Guy will be taking an in-depth look at the types of ants in Florida. This series of articles is by no means a comprehensive list; we are just going to look at the most common types of pest ants found in and around Florida homes. We’ll show you how to identify them, why they are a nuisance, what you can do to prevent them, and how to treat for them if you become infested.
There are three main categories that ants fall into:
Worldwide, there are over thirteen thousand different species of ant. Florida is home to about two hundred and fifty species of ant, of which, only six are native. Fifty-seven species are classified as exotic or invasive, and the remaining have migrated into the area, through commerce, hitchhiking, and other natural means. This first article in this series is going to take a look at one from each of those categories, which also happens to be the top cause of pest control inquiries from Florida homeowners. Our next post will look at some of the other common species, and we’ll wrap up with several new species of ant that have been discovered in Florida.
The top named indoor pest species in Florida is the Ghost Ant, and 20% of all ant complaints by Florida homeowners turn out to be Florida Carpenter Ants. The most dreaded ant species in Florida is the Red Imported Fire Ant (RIFA). There are about 20 or so species of ant that a homeowner will see prompting them to call their friendly neighborhood pest control professional. Many times homeowners will mistakenly call their pest control professional thinking they have termites, when in fact, they have ants.
The Difference Between Ants and Termites
Ants and termites are often confused, as reproducing ants also have wings. These wings are typically present during flight season when mature males and females leave their nests with the sole purpose of reproduction. The mating season generally happens in the spring and summer months, and when pest control professionals most often receive these calls. The main difference between “flying ants” and termites are their wings. Termite wings are all the same size, while ant wings have larger fore wings and smaller rear wings. An ant body is composed of three main parts: the head, the thorax, and the abdomen. All six legs of an ant are attached to the thorax section. The main anatomical difference between ants and termites is a slender waist, or petiole, separating the thorax and abdomen. A termite does not have the slender petiole. Ant species also have elbowed antennae, unlike termites. Both ant and termite heads are comprised of eyes, antennae, and mandibles used for carrying food, fighting, and other tasks. Did you know that some ant species can carry ten to fifty times their weight? That’s the equivalent of a human with the ability to lift a car!
What Do Ants Eat?
Ants are generally attracted to two primary food sources, either sweet foods or proteins. Ants are highly social and live in structured nest colonies. These colonies can be located underground, in trees, or in the mounds you see on your lawn. Lower worker ants are responsible for feeding the entire colony. While nearly everyone finds ants to be problematic, some ant species are beneficial to the eco-system. Ants are the natural garbage men of the earth. They are decomposers, helping to keep the environment clean by feeding on organic waste, dead animals, and other insects.
On the other hand, invasive species, such as the Trap-Jaw, can be devastating to native species and harmful to humans, due to their venomous bite. Argentine Ants in Florida are considered an invasive species with serious ecological repercussions because they have no natural enemy to help keep population density under control. Read on to learn about three of the most common types of ants found in Florida.
Tapinoma melanocephalum, or ghost ants are the number one pest ant species in Florida. They are a nuisance insect and live mostly in Central to Southern Florida. These ants have appeared throughout the North American continent but are limited to indoor locations in colder regions. Those areas with temperate conditions meet their necessary habitat for survival. North of Gainesville, this ant begins to restrict itself to indoor nesting only. The origin of the Ghost Ant is unconfirmed, starting in either Africa or East Asia, and has been widely distributed through commerce. Ghost ants are tiny, ranging in size from 1.3 to 1.5 mm long (about .05 inches). The head and thorax are dark brown while the abdomen and legs range in color from opaque to a creamy white color. The antennae of the Ghost Ant thicken toward the end.
Ghost ants are problematic in Central and South Florida because they can live both indoors and outdoors. While indoor Ghost Ants eat many household foods, they prefer sweet sugars and syrups. Outside they tend to habitat with insects that are honeydew bearing, feeding off the by-product of these bugs. Colonies that live outdoors are also found feeding on the carcasses of dead insects. These ants are a nuisance pest in households because they can live anywhere within your home. They are commonly found nesting underneath cabinetry, behind walls and baseboards. They have been observed taking up residence anywhere that is dark and undisturbed, even in between books! Pharaoh ants display similar nesting habits to the Ghost Ant. These ants are a species that create what is known as supercolonies. Meaning several nests can be found with multiple queens. The impact is that the population of these ants will increase dramatically when this occurs, and controlling the population becomes more difficult with multiple nests in the home.
Ghost Ant Management
The best approach to any pest problem is cleanliness. Leaving crumbs on the counter or open food containers will ultimately bring in unwanted critters. Be sure to keep countertops and floors clean of food debris and seal food in airtight containers. Plants can also attract several types of bugs, not just ants. Many ant species live symbiotically with other beetles, flies, and aphids. Reduce plants in your home that may attract these kinds of insects, and you will control the ants that feed on their honeydew. Also, keep outdoor plants from touching the exterior walls as this makes transfer into the home much simpler for the ants. If you have gaps or leaks in your house, this is where most pests, including Ghost Ants, will enter. Make sure to caulk or seal any holes or cracks in your foundation, walls, or other places critters might enter. Finally, if you have a Ghost Ant infestation, it is best to attempt to find the nest and treat that directly. You can follow the ant trails back to the nest and use any number of available insecticides to treat it. If you can’t find the nest, place baits where you have seen the ants, and they will carry this back to the nest for you. Still, this method of treatment usually takes longer to control the population. Contact poisons will also work, but will not always treat the nest, as the workers may die before returning to the colony. The goal of any ant treatment is to make sure it makes it to the queen so she will not reproduce.
There are two types of fire ants found in Florida. The most common is Solenopsis invicta or the Red Imported Fire Ant (RIFA). Less commonly found is Solenopsis geminate, the Tropical Fire Ant. The less common species is native to Florida’s sub-tropical climate. However, the RIFA has much more population density than the Tropical. RIFA originated in Brazil and has been in the United States since the mid-1930s, most likely starting in the Florida Panhandle or Mobile, Alabama, transported on ships carrying crops to the region.
RIFA worker ants can range in size from 2.4-6mm (1/8”-1/4”). RIFA has several distinct features, including a stinger located at the tip of their abdomen. The mandibles on the head include four teeth, and the antennae have a distinct two-segmented club at the end. Their body color ranges from red to brown with a black abdomen, and the waist has two segments. The main difference between the Red Imported Fire Ant and the Tropical Fire Ant is the shape of the head. Tropical fire ants have a square-shaped head that is disproportionate to the rest of their body. RIFA mounds can be found under concrete slabs, under the edge of foundations or driveways, and in lawns. Piles typically do not get larger than eighteen inches in diameter. When a RIFA mound is disturbed, worker ants will emerge both biting and stinging its trespasser. Because the sting contains venom, that is responsible for the pain and white pus that forms around the sting site, about a day after the attack. This venom can cause anaphylactic shock in sensitive individuals; however, most individuals are simply left with red raised bumps filled with pus after being stung. The concern is heightened when swarms attack an individual leaving numerous stings because the venom contains necrotoxic compounds, which can destroy tissue cells.
Economic Impact of Red Imported Fire Ants
Red Imported Fire Ants are especially problematic in Florida due to their agricultural destruction. RIFA are opportunistic protein feeders and, therefore, will feed on young plants, significantly reducing crop numbers. Significant losses have been reported on soybeans, corn, peanut, citrus, okra, bean, cabbage, and sunflower crops. Red Imported Fire Ants feed on the young roots of these plants, restricting plant growth and reducing yield. In urban settings, because they nest under sidewalks, driveways, and concrete slabs, they can weaken these structures causing them to crumble. Thus making human paths unsafe to walk on and creating city government and homeowners alike to foot the bill for repairs. However, RIFA does have its benefits, as they have been reported to help reduce the prevalence of ground-nesting rodents. State and Federal costs are around $250 million to control or eradicate fire ant populations, and homeowners spend and additional $20-40 million per year on fire ant control.
Fire Ant Management
For home fire ant management, individual mound treatment is the most common method. This process can be in the form of dusts or granules spread atop the mound, which are then soaked in. This approach does not always kill the queen, which is the ultimate objective of any ant management course of action. Mound injections, or the pouring of toxic liquids into the mound, also has a similar effect, you will thin out the density but rarely kill the queen. Baits are usually the most effective form of control because the worker ants will feed on the pesticide and bring it back to the queen. This process is a slower but more permanent solution to the extermination of a colony. There is a popular old wives tale that says pouring boiling water on the mound will control fire ant populations, but this is not necessarily true. Like mound treatments and injections, this will only kill a portion of the colony, and very seldom the queen. Red Imported Fire Ants are often multiple Queen colonies capable of producing up to 1500 eggs per day. So, this method of pouring boiling water into the mound is merely a short-term solution. It can be dangerous to the person handling it both by fire ant attack and scolding accidents.
Florida Carpenter Ant
20% of all ant complaints made by Florida homeowners in major metropolitan areas are discovered to be one of two species of carpenter ant. The first, Camponotus floridanus or the Florida Carpenter Ant, and the second, Camponotus tortuganus or the Tortugas Carpenter Ant are both native pests, and the largest ants found in Florida. Neither are wood destructive as their name might imply, preferring instead to nest in wood softened by moisture or fungi. Florida Carpenter Ants are most often spotted during flight (mating) season. They are the most commonly mistaken ant for termites because of both their size and the wings present during mating. Florida Carpenter Ants are dispersed throughout North and South Florida. Tortugas Carpenter Ants are found more in West Central and South Florida regions.
Worker ants range in size from 5.5-11mm (1/5-2/5”)in length. Queens can reach up to 20mm (3/4’) in length. The head and thorax of these ants range from a greyish brown to rusty orange color with a black abdomen. A distinct feature of all carpenter ants is the smooth curve of the thorax. Both Florida and Tortuga Carpenters have long, broad heads, though Tortugas are slightly narrower and have paler coloring. Neither of these ants can sting, though they can bite, and will spray formic acid as a means of defense.
Carpenter Ant Management & Nesting Sites:
Carpenter Ants, like many ants, are more of a nuisance pest. Many pest control professionals have found it difficult to completely eradicate problems in homes since these ants will find moisture-laden voids under bathtubs, in eaves and under appliances where reaching the nest and treating it proves to be complicated. Carpenter Ants prefer sweets over proteins, but outside nests do feed on dead insects as well as the honeydew produced by other insects.
Carpenter Ants are extremely difficult to manage given their preferred nesting sites in hard to reach places. Treatment often proves unsuccessful because if an insecticide is placed near to, but not on the nest, the Carpenter Ants will simply move to a new location. For exterior infestations, removing rotting wood, garden clipping, and rotting tree stumps will significantly reduce the attraction to the area. Remember, Florida varieties of Carpenter Ants prefer to nest in hollowed out moisture-laden environments. Baits can work on Carpenter Ants but should be placed in multiple sites. Carpenters are notoriously picky eaters, and only small groups of foragers will travel to a single food source.
Q: Why do ants march in a straight line?
A: Most ant species leave a pheromone trail leading back to their nest. Other worker ants can follow the path to the food source and find their way back to the nest.
Q: Why do you often find multiple mounds very near to each other.
A: Many ant species co-exist in what is known as supercolonies, meaning there is no competition for food. They merely help each other out in small communities. Multiple mounds or nests appear due to budding, which is the act of one or more reproductive females, along with workers leaving an established colony to create a new nearby nest. These ants often take larvae and pupae with them along with food to help them establish the new site.
Q: What purpose does a single ant have in the colony?
A: Most ants are worker ants and serve no purpose other than to ensure the survival of the colony by feeding the queen and tending to the young (larvae and pupae). Every single ant has a job to do in the colony; some are foragers, some are scouts, some soldiers, and other nurses. The queen’s sole purpose is to lay eggs.
Learn more about the common types of ants in Florida with Part Two of our Three-part Ants of Florida Series.