Pest Information - Ants
There are almost 9,000 species of ants and they can be found from the Arctic Circle to the Tropics. This site will focus on the ants most commonly found in Hawaii. Learn about their Appearance, Habitat, Diet, Type of Damage, and Life Cycle.
Crazy Ant
Scientific Name
Paratrechina longicornis
Appearance
Crazy ants are so called due to their characteristic erratic and rapid movement. They also do not follow typical ant trails as frequently as other ants. Worker ants are 1/16- to 1/8-inchs (2.3 to 3 mm in length). The crazy ant can be distinctive. They are dark brown to blackish in color although the body often has faint bluish iridescence. The antennae are extremely long containing 12-segments, the first being the longest at twice the length of the head. Their legs are also extraordinarily long. The petiole is wedge-shaped, with a broad base, and inclined forward.
Habitat
The crazy ant is highly adaptable, and nests in both dry and moist habitats. The foraging area is extensive. Nests are typically found in such places as trash, refuse, soil, rotten wood and in plant and tree cavities, even under building debris. Crazy ants gather around human dwellings, attracted to the light. Gasoline stations, convenience stores, and sidewalk cafes are particularly attractive, anywhere where food is dropped. During the winter months in cold climates, the ants may nest indoors, feeding on many household foods.
Originally from Africa, the longlegged ant has been widely transported throughout the tropics by man. This ant was first reported in Hawaii on Oahu in 1952 and has subsequently spread to the islands of Hawaii, Maui, and Kauai. The ant is abundant on Hawaii in the Hilo and Puna districts and at Hana on the island of Maui. It is usually found from sea level to about 2000 feet.
Diet
These ants feed on a variety of foods including grease, sweets, and other insects. In some areas they are considered a biological control agent for houseflies. They also tend aphids and scales to feed on their honeydew. While crazy ants need moisture, elimination of water by itself will not get rid of these ants since they can survive under a wide range of conditions. Elimination of food sources and nest sites are equally important in the management of this ant.
Workers are omnivorous, feeding on live and dead insects, seeds, honeydew, fruits, plant exudates, and many household foods. They apparently have a seasonal preference for a high-protein diet, and during the summer months may refuse honey or sugar baits. They are attracted to honeydew producing homopterans in spring and fall. They obtain honeydew by tending aphids, mealybugs, and soft scales. Large prey items are carried by a highly concerted group action.
The workers are known to gather small seeds of such crops as lettuce and tobacco from seedbeds. In cold climates, the ants nest in apartments and other buildings where they are potential pests year round. Workers feed on many household foods such as meats, grease, sweets, fruits, vegetables, and liquids.
Type of Damage
This ant does not damage plants. Instead, the longlegged ant contributes to the development of honeydew producing insects. They aid in the dispersal of these insects and also indirectly contribute to increased damage by protecting the colonies against natural enemies.
Their nest burrowing activity at the base of trees subject the roots of the plant to invasion by diseases.
Life Cycle
Ant colonies live in nests that may be located under ground or in trees. Nest size averages about 4000 individuals. Approximately 80% of the population are workers, 15% are queens, and the remaining percentage is composed of eggs, developing larvae, and pupae. There is an increase in nest size and foraging activity during drier months. Workers live for approximately 6 months, the queens for several years. Queens lay about 700 eggs annually throughout their life span..
Interesting Facts
The Invasive Species Specialist Group of the World Conservation Council lists the Crazy ant at number six in the world’s worst 100 invasive species. Red fire ants are listed at number 86.
Ghost Ant
Scientific Name
Tapinoma melanocephalum (Fabricius
Appearance
Ghost ants look like tiny, white apparitions who suddenly appear and seem to disappear just as quickly. Workers are 1/16 inch/1.5 mm in length. The legs, pedicel, gaster, and antennae are pale, almost translucent, in color and the head and thorax are darker. For this reason, the ghost ant is also known in some areas as the black-headed ant.
Habitat
The ghost ant is highly adaptable in its nesting habits. It nests readily outdoors or indoors. Colonies may be moderate to large in size containing numerous reproducing females (polygyny). Generally, the colonies occupy local sites that are too small or unstable to support entire large colonies. The sites include tufts of dead but temporarily moist grass, plant stems, and cavities beneath detritus in open, rapidly changing habitats. Indoors, the ant colonizes wall voids or spaces between cabinetry and baseboards. It will also nest in potted plants. Thus, the colonies are broken into subunits that occupy different nest sites and exchange individuals back and forth along odor trails. Ghost ants are opportunistic nesters in places that sometimes remain habitable for only a few days or weeks.
Diet
Like many pest ants, ghost ant workers prefer the honeydew secreted by aphids and mealy bugs. These ants will protect bugs from predators, insuring the safety of their living food source. Not only do they crave the honeydew from aphids, ghost ants have a definite "sweet tooth" when foraging through your home. Any candy, sugar or other sweets are fair game to these little guys. Because of their size, ghost ants are often not found until someone is well into preparing food.
Type of Damage
This species is a household pest. The ghost ant will not only invade houses from the outside, it can nest in the house as well. In Florida, the ghost ant has infested quarantine greenhouses where they have proven impossible to control due to the restrictions imposed on the use of toxicants in these greenhouses. In more northern areas, it has become established in heated greenhouses where it can become a problem, especially if it defends honeydew producing plant pests against introduced biological control organisms..
Life Cycle
Multiple ghost ant queens may be spread out in multiple subcolonies. New colonies are probably formed by budding. This occurs when one or more reproductive females, accompanied by several workers and possibly some brood (larvae and pupae), leave an established colony for a new nesting site. There does not appear to be any infighting between members of different colonies or nests. Mating takes place in the nest and no swarms are known to occur.
Interesting Facts
When crushed, the ghost ant workers emit an odor similar to that of rotten coconuts.
Pharaoh Ant
Scientific Name
Monomorium pharaonis
Appearance
Pharaoh workers are very small (about 1/16-inch long), light yellow to reddish brown in color with the abdomen (hind portion of body) somewhat darker. There is no stinger. The petiole (narrow waist between the thorax and abdomen) has two nodes and the thorax has no spines. Eyes are well-developed. The antennal segments end in a distinct club with three progressively longer segments. This is in contrast to the thief ant's two-segmented club.
Habitat
Pharaoh ant nests are often so small it can be contained in a thimble, located between sheets of paper, in clothing or laundry, furniture, foods, etc. Nests usually occur in wall voids, under floors, behind baseboards, in trash containers, under stones, in cement or stone wall voids, in linens, light fixtures, etc. They prefer dark, warm areas near hot water pipes and heating tapes, in bathrooms, kitchens, intensive care units, operating rooms, etc. They are "trail-making" ants and often are found foraging in drains, toilets, washbasins, bedpans and other unsanitary sites, as well as in sealed packs of sterile dressing, intravenous drip systems, on surgical wounds, food, and medical equipment.
Diet
Pharaoh ants feed on a wide variety of foods including jellies, honey, shortening, peanut butter, corn syrup, fruit juices, baked goods, soft drinks, greases, dead insects, and even shoe polish.
Type of Damage
Pharaoh ants have become a serious nuisance pest in hospitals, rest homes, apartment dwellings, hotels, grocery stores, food establishments and other buildings. Pharaohs gnaw holes in silk, rayon and rubber goods. These ants are capable of mechanically transmitting diseases and contaminating sterile materials.
Life Cycle
Female Pharaoh Ants can lay 400 or more eggs in her lifetime. Most lay 10 to 12 eggs per batch in the early days of egg production and only four to seven eggs per batch later. At 80°F and 80 percent relative humidity, eggs hatch in 5 to 7 days. The larval period is 18 to 19 days, prepupal period 3 days, and pupal period 9 days. About four more days are required to produce sexual female and male forms. The entire life cycle takes about 38 to 45 days depending on temperature and relative humidity. Unlike most ants, they breed continuously throughout the year in heated buildings and mating occurs in the nest. A single queen can produce many hundreds of workers in a few months. Mature colonies contain several queens, winged males, sterile females or workers, eggs, larvae, prepupae, and pupae growing to as large as 300,000 or more members. Periodically, a queen, together with a few workers carrying immatures (eggs, larvae and pupae) leave the nest and sets up a new colony elsewhere, quickly spreading an infestation. This behavior pattern is known as "satelliting," "fractionating", or "budding" where part of the colony migrates to a new location rather than by single females dispersing after a reproductive swarm. Budding may occur due to overcrowding, seasonal changes in the building's central heating and cooling system or application of a repellent pesticide.
Interesting Facts
In hospitals, foraging ants have been found in surgical wounds, I.V. glucose solutions, sealed packs of sterile dressing, soft drinks, water in flower displays, and water pitchers. Some feel Staphylococcus and Psuedomonas infections, occurring from time to time in hospitals, are associated with these ants.
Little Black Ant
Scientific Name
Monomorium minimum
Appearance
The little black ant's thorax lacks spines, and the petiole has two nodes. The abdomen is tipped by a small stinger. Each antenna ends in a three segmented club. The little black ant workers are 1/16-inch long. These characteristics also describe these two species is the jet black color of the little black ant.
Habitat
Little black ants are found throughout the United States. They nest beneath stones, in lawns, and in areas that lack vegetation. Their nests are easily located because they form small craters of fine soil at their entrances. These ants also nest in rotting wood and behind the woodwork or masonry of structures. Indoors, they can be found under the edge of carpeting, in old termite galleries, and in wall voids.
Diet
Little black ants like to feed on a variety of foods. They eat aphids as a source of honeydew, feed on meats or greases, and are predaceous on other insects. Indoors they feed on both greases and sweet foods.
Type of Damage
A common house ant in Hawaii, this ant poses two problems. One is that it bites if disturbed, the other is that it encourages plant pests by protecting aphids, mealybugs, and other pests that destroy plants. The little black ant feeds on “honeydew” produced by these plant pests.
Life Cycle
Not a great deal has been published on this ant species. The colonies are moderate to large and contain numerous queens. Winged reproductives appear from June to August.
Interesting Facts
As with other species of ants, it is important to remove vegetation that touches the home because these ants will use the plants as bridges into your home.
