Types of Ants in Florida-Pt 2
Ants are a nuisance. Several types of ants can infest homes when they nest in your walls and under your appliances or build unsightly mounds in your backyard. Some species of ants can even bite or sting, leaving you with a painful reminder of their presence. Ants contaminate our food and expose us to illnesses such as E. Coli or Salmonella. There are many types of ants in Florida. Previously in this three-part series, we discussed the three most common ants found in Florida: the Ghost Ant, the Fire Ant, and the Carpenter Ant. Next, we’ll discuss some more common Florida pest ants found in and around your home.
The most common species of pest ants in Florida include:
- White-Footed Ant
- Pharaoh Ant
- Acrobat Ant
- Bigheaded Ant
- Pavement Ants
- Crazy Ants (including Black, Caribbean & Robust)
- Argentine Ant
- Rover Ant
- Pyramid Ant
- Thief Ant
Some ants can be confused with termites, due to the wings present during flight season, another name for the ant mating season, usually occurring between April-August. The easiest way to distinguish ants from termites is by looking at the area where the thorax and abdomen connect. Ants have a small, slender waist or petiole, while termites lack a distinct petiole. Also, the wings of these two insects differ significantly. Termites have consistent wing length between fore and rear wings, while ants have smaller rear wings.
Ants are social insects, with a hierarchy. There are scouts who explore on their own looking for food sources that they bring back to the nest leaving behind a pheromone trail which groups of foragers follow to collect the food to bring back to the nurses who are tending to the young. Some species include soldier ants, which often have more massive mandibles used in fighting. The queen is at the top of this hierarchy, and her only responsibility is to produce eggs. Some ants live in single colonies with only one queen. In contrast, others live in supercolonies consisting of many queens and nesting sites. Those that live in supercolonies generally do not compete, but rather, work as a whole community sharing food sources and workers without fighting.
Let’s explore a few of the other common types of ants in Florida, how to identify them, and how to manage them if you do get an infestation.
White-footed Ant (WFA)
The White-Footed Ant, or Technomyrmex difficilis, is not native to Florida and was discovered first at a nursery in Homestead in 1986.
WFA can be found throughout the southern United States, San Francisco, and Hawaii, as well as in the West Indies, South America, and Sri Lanka. They were likely introduced through the transport of residential landscaping plants and fruits. In Florida, the White-Footed Ant is concentrated mainly in South Florida but has been confirmed as far north as Clay County. WFA can be identified due to its unique coloring. They are a small ant measuring only 2.5-3mm (less than 1/10″) long, with dark brown to black head, thorax, and abdomen. Their legs start in the same color, changing to a pale yellowish color from the mid-tibia to the feet. The ends of antennae, from the elbow forward, are also this same pale-yellow color. Nesting sites are found in the same places where most other ants are located; in spaces between walls and under sinks or other moisture-rich environments. However, most nests are seen outside the walls of homes in shrubs, loose mulch, under garden clippings or palm fronds.
White-footed Ants do not bite or sting and have no soldier ants in their colonies. However, they are considered to be one of the most challenging species to manage because they are one of the only types of ants that will not carry the bait back to the colony. Still, they will share poisoned food between workers, which often causes starvation of the young due to reduced population. This method will not kill the queen, which is always the most permanent solution to any course of ant extermination practice. One the best ways to control these ants from interior infestation is to be sure that no exterior plants are touching the outside walls of your home. Overhanging trees should also be trimmed back so that leaf nests do not fall onto the roofs of buildings. If you do have an interior infestation, aerosol or dust insecticides sprayed through holes drilled in walls outside the nest is most effective. Because WFA creates such broad groupings of nests (supercolonies), finding all nesting spots is imperative to a permanent solution.
Nearly every one of us has had to contend with Pharaoh Ants at some point in our lives. Monomorium pharaonic, or Pharaoh Ant, was named because it was misidentified as being one of the plagues of ancient Egypt. These ants are more commonly known as sugar ants. They are found throughout the world, though likely originate in the Northern regions of Africa. Ghost Ants and Pharaoh Ants are similar in community structure and nesting habits. This ant is almost always found indoors, except in the southern hemispheres where it has adapted to field conditions. Though the WFA has gotten a reputation as being a problematic species to exterminate, the Pharaoh Ant has earned the distinction of being the most problematic ant species to control due to the nature of their supercolonies and sheer numbers once an infestation occurs. The budding habits (creation of new colonies) of this species means they are quick to multiply in numbers. They are another small species measuring only 1.5-2mm (.05″) in length, their color ranges from light brown to red, with a darker abdomen. Whereas most ant species have a single petiole (waist), worker Pharaoh Ants have two, a petiole and postpetiole. These ants also have a stinger, but rarely use them. Pharaoh Ants can carry over a dozen different diseases such as E. Coli, Strep and Staph as well as Salmonella. Their nuisance status stems from their ability to get into even the tightest and cleanliest of spaces. Pharaoh ants have been found in homes, bakeries, factories, office building, and even in hospitals seeking moisture from in-use IV bottles, yuck!
Pharaoh Ants will nest just about anywhere and have been found in the oddest of places. Nests can occur in linens and clothing, in trash piles, and even between sheets of paper. Their ability to rapidly spread and colonize is one of the reasons management is so difficult. As soon as one nest is even slightly disturbed, groups will leave and form a new nest. Liquid and dust insecticides encourage this behavior, so the best form of extermination is to spread baits throughout the infested structure, ensuring that all colonies are fed the poison. Outside baits should also be placed in warmer climates to eliminate new colonies from moving in. Baiting extermination programs can take up to a year to complete depending upon the extent of the infestation.
Bigheaded Ant (BHA)
Pheidole megacephala, or the Bigheaded Ant, is an invasive species in Florida originating from Mauritius Island located East of Madagascar in the Indian Ocean. This species of ant often displaces other native and non-native species, such as the Red Imported Fire Ant. It is believed to have drastically expanded its population density due to increased hurricane activity in Southern Florida between 2003-2005. The resulting damage from the hurricanes triggered increased amounts of landscaping materials to be brought in from other areas to replace vegetation after the storms. The BHA is already prevalent in tropical and sub-tropical regions and had been found in Florida prior to these extreme hurricane seasons.
The Bigheaded Ant is often confused with subterranean termites because of its use of foraging tubes, which are similar in appearance to termite tubes. BHA often displace soil and leave debris where they forage. There are two classes of worker BHA, major and minor, and these differ significantly in size with minor workers averaging around 2mm (1/16″) and major workers as large as 4mm (1/8′) in length. Their bodies are reddish-brown and are another species with both a petiole and a postpetiole (2 node waist). Major workers are the ones with the larger heads comparative to the minor workers and legs are generally lighter in color than the rest of their body, and are also often mistaken by homeowners for the White-footed Ant species. Major workers are often the soldiers of the colony, protecting the minor workers and providing help when necessary.
Some people mistakenly believe they have Red Imported Fire Ants when, in fact, outdoor nests are BHA. Both of these ants similarly nest in lawns and flower beds, and under the concrete slabs of driveways and walkways. BHA will also attack and bite if their nest is disturbed but do not have stingers, nor are they venomous. The most significant difference is that BHA will travel along foraging trails (similar to subterranean termites). Therefore, they can usually only be spotted due to the disturbance of soil and debris piles around foraging sites.
Both baits and liquid insecticides can be used to control Bigheaded Ant colonies. However, due to outdoor colonies spreading across property lines, it can be challenging to eradicate the problem. BHA are rapid colonizers, so effective treatment must be a communal effort. As with most ant species, sealing up cracks and leaks can help to prevent indoor infestations. Spraying along foundations, and under objects like flower pots or lawn decorations should prove to be an effective deterrent, keeping outdoor foragers from entering a structure. Indoors the same methods will be helpful, but to prevent health risks to humans, bait traps in child-proof containers are available. Granular baits or liquid insecticides can be safely injected into walls to ensure the rapid depopulation of workers and extermination of queens.
No, the ant you saw zig-zagging across your patio isn’t drunk. Crazy Ants get their name due to their erratic patterns of movement, seldom following trails as most other ant species do. Their scientific name, Paratrechina longicornis, is due to the abnormally long antennae of this species. They also have legs that longer than most other species of ant. These ants are commonly referred to as the Black Crazy Ant. This species often travels far from their nests for foraging making extermination difficult because the nests are hard to find. There are several other types of crazy ant associated with this species, including the Caribbean, Robust, and Tawny varieties. These ants are not native to the United States, originating in Southeast Asia. They can live just about anywhere, including on ships at sea. Next to the Pharaoh Ant, this is one the most widespread species of ant on the planet.
Identification, Nesting, and Management
The Crazy Ant is one of the smaller ant species, measuring just 2.3-3mm in length (about 1/10″). They are dark brown or black, sometimes displaying a slight blueish tint. Crazy Ants can live indoors or outdoors in moderate climates, though they stay indoors as climates get cooler. They are adaptable to both dry and moist environments. Outside, their habitat consists of rotting wood, such as fallen tree limbs or stumps. They also build nests under bricks and stones. They can be found in potted plants or mulched plant beds. Inside you can find them behind walls, beneath floors and especially around water heaters and pipes. They live in modestly sized colonies with just a few thousand workers, but up to 40 queens. Crazy Ants do bite and can inject a formic acid onto the wound by curling their abdomen around.
Nesting sites, as previously stated, are often far from where workers are found foraging. Typical ant prevention methods such as sealing cracks or gaps on walls can aid in the prevention of indoor infestations, as well as keeping areas clean of food debris. Outside, removing yard debris, tidying up rotting or fallen wood, and removing leaf piles will help reduce nesting. Removing yard ornaments or other accessories that create moisture underneath will help discourage ants from colonizing in these areas. Prevent accidental spreading by checking lumber or other objects for ants before moving it to a new location. If infestations do occur, nearly all commercial insecticides and baits will work on population reduction. Finding the nest by following foragers carrying food is the best way of locating the nest to treat it and kill the queen(s).
Did you know?
Ants are very much like human workers in that they keep regular daily shifts for working, sleeping, and eating. They even stretch and yawn upon waking.
Columbians like big butts! The Fat-Bottomed Ant is a delicacy in this region. According to scientists, it tastes just like buttered popcorn. (We’ll take their word on that!)
Ants have 250,000 brain cells and are considered the world’s smartest insect.
You can’t drown an ant. They breathe through their exoskeleton, but the openings for air are so small that water cannot penetrate. They have been observed to live underwater for up to two weeks.
Most colonies of ants are female. Males are only used for reproduction and die off shortly after mating. Scientists have discovered an Amazonian ant that reproduces completely asexually.