|Urban Knowledge Master|
Camponotus variegatus (Fr. Smith)
|Hawaiian Capenter Ant|
Julian R. Yates III
Extension Urban Entomologist
College of Tropical Agriculture and Human Resources
University of Hawaii at Manoa
These ants will feed on small insects, honeydew from aphids, and most foods found in a home, including meat and grease.
Southeastern Asia, Midway, Hawaiian Islands
Although it is primarily found outdoors, the Hawaiian carpenter ant will establish nests in wood that has previously been hollowed out by termite or inside rotting logs and tree stumps. For this reason and because of its name, it is often incriminated as a wood destroyer. Although it may do some excavation of wood, it does not consume wood like termites and does little to no damage to wooden structures. Species of carpenter ants in the Pacific northwest and eastern parts of the United States, however, are serious wood destroyers and have rivaled termites in their importance.
During certain times of the year, there are also winged males and females. These individuals will swarm and mate. The fertilized female then seeks a suitable place to start a nest. This may be a natural cavity in wood or soil. She seals herself in and lays her first batch of eggs. This ant undergoes complete metamorphosis: egg, larva, pupa, adult.
The first workers take on tasks of nest-building, foraging to feed the next larval generation, and care of the queen. Workers are sexually undeveloped females, and as the colony increases, various sizes of workers are produced. They are often described as being minor, media, and major workers, depending on their size. The minor and media workers perform most of the work in the nest including taking care of the eggs, larvae, pupae, and reproductives. These small workers seldom leave the nest. The major workers guard the nest, fight intruders, explore, and forage for food.
The elongated, whitish eggs hatch in about 20 days.
The queen feeds the larvae a fluid secreted from her mouth. This nourishment is derived from her stored fat bodies. The larvae grow for about 28 days before spinning cocoons around themselves and pupating.
The pupal stage lasts about 22 days. It is this stage that is often mistaken for eggs. The first small workers chew their way out of the cocoons and begin to assist the queen.
Adults of this ant measure from 5 mm to 1.27 cm in length and are Hawaii's largest ant species. They are typically yellowish-brown with dark brown stripes across the top of the abdomen. Because of their size and color, winged adults of the Hawaiian carpenter ant are often confused with the winged adults of the West Indian drywood termite and the Formosan subterranean termite, since the reproductives of both groups tend to swarm (appear) at approximately the same time of the year. Several morphological characters can be used to differentiate these individuals.
The workers are nocturnal in habit, and their foraging behavior may extend to midnight or later. If the carpenter ant has established a nest in a home, it is not unusual to see them on the walls and ceiling at night. These individuals may be the winged sexual reproductives after a swarm and/or foraging workers looking for food. These ants will feed on small insects, honeydew from aphids, and most food found in a home, including meat and grease.
The appearance of approximately six or more foraging workers indoors is a good indication that the pest has established a nest somewhere in the home. Eradication of the ant, indoors or outdoors, will require the location and destruction of the nest--not insecticidal spraying of the foragers. There are several indoor places they favor, including wall clocks, pianos, hollow-core doors, double walls, toe space beneath built-in counter cabinets, cardboard boxes used for storage, suitcases, infrequently used dresser draws, and pots and pans.
Determine the room of the home from which ants originated by observing the movements of the foraging workers. This will simplify the search for the nest. If a hollow-core door is suspect, one can bang on the door, then place an ear against the door to listen for rustling sounds. If ants are present, remove the door from its hinges to the outdoors, look for the ant entrance/exit hole at either the top or bottom edges of the door, and spray an insecticide through the hole. A convenient and effective insecticide to use is an aerosol (such as Term-Out) equipped with a flexible hose and needle-nozzle, which facilitate the spraying of the insecticide into the hole.
If the nest is situated in an immovable object, spray the ants with an insecticide; however, they will probably scurry to other parts of the home before dying.
Moore, H. B. 1979. Wood-inhabiting insects in houses: Their identification, biology, prevention, and control, U. S. Forest Service, Department of Agriculture, with U. S. Department of Housing and Urban Development.
University of Kentucky. 1987. Professionalism reconsidered. Seventh annual pest control short course manual. College of Agriculture, University of Kentucky, Lexington.
Vector Control Branch. 1982. Vector control manual. Hawaii State Health Department, Honolulu.
Wilson, E. O., and R. W. Taylor. 1967. The ants of Polynesia (Hymenoptera; Formicidae). Pacific insects monograph 14. Entomology Department, Bernice P. Bishop Museum, Honolulu.