Species Info General

Other common names include: Common House Ant, Little Red Ant, Little Yellow Ant, Hospital Ant, Ship Ant, Red Domestic Ant

Pharaoh Ants are a notorious invasive species, though as will be explained below its impacts in the Islands are rather muted.  In their remarkably thorough book on Fiji’s ants, Sarnat & Economo (2012) wrote “This species is one of the most accomplished tramp ants in the world, and has demonstrated a remarkable ability to persist in human habitations, hothouses and food processing plants across the globe.”  Fullaway & Krause (1945) wrote of this species: “It is often found on ships, and undoubtedly has been carried about in commerce to the ends of the earth.”  E. O. Wilson (1964) called it “perhaps the ant most intimately associated with [humanity]”, while Smith (1965) called it “one of the most common and best known of all house-infesting ants.”  Smith went on to say “The Pharaoh ant probably occurs in every town or city of commercial importance in the United States.  Although not widely or uniformly distributed in such localities, it is especially common in hotels, large apartment houses, groceries, or other places where food is commercially handled.”

Forel (1901) had these tough words to say about the invasive Pharaoh Ant: “Dieser scheusslichste aller Kosmopoliten kommt von den Kolonialwaarenhandlungen” which roughly translates to “This most hideous of all cosmopolitans comes from the colonial goods trading companies”.  This was one of the first tramp ants to travel the globe, with Viehmeyer (1906) writing “hat diese Ameise ziemlich die ganze Erde erobert” or “this ant has conquered almost the entire world.”  Reporting on this ant in Germany, Viehmeyer went on to write “It prefers to build its nests in bakeries, bathhouses, and public buildings with central heating – in short, warm places – and its extraordinary rate of reproduction can make it quite a nuisance.”  Marlatt (1928) wrote “It has attained a thoroughly cosmopolitan distribution and has been domesticated so long that it is now difficult to determine its exact origin . . .  It was originally a soil ant, nesting out of doors in warm countries, and doubtless continues this habit in the Tropics of both hemispheres.  In temperate regions it passes its entire existence in heated houses.”  Smith (1936) reported that this species “is highly adapted for living in urban areas, where its very populous colonies nest in the woodwork and masonry work of dwellings, stores, etc”.  Of this ant in the lower 48 United States, Smith (1965) wrote that “[t]he Pharaoh ant is without doubt the most persistent and difficult of all our house-infesting ants to control or eradicate.”

Perhaps worst of all, however, is the fact that Pharaoh Ants are notorious invaders of hospitals (O’Rourke 1956, Wetterer 2010).  Hospitals are structures where the temperature and humidity are kept at a constant level day and night, all year long – conditions that this ant finds very attractive.  Aside from the fact that no one in a hospital wants to be further annoyed by ants on top of their other worries, O’Rourke (1956) (referencing Jettmar 1935, Gösswald 1939, and Busvine 1951) reported that this ant is known for spreading disease: “Gösswald (1939) has emphasized that Monomorium pharaonis L. may spread disease in hospitals.  This ant is often found feeding on dead bodies, excreta, wet dressings, sputum and on the open sores of patients. . . . The frequency with which this species is found in many hospitals is certainly rather striking.  It is liable to enter beds and irritate patients and may even bite small infants and cause them considerable distress.”

Despite this ant’s awful reputation, however, records of it on Maui are extremely limited, and it seems that it has never achieved the invasiveness here (whether in homes or in hospitals) that it shows in other parts of the world.  Huddleston & Fluker (1968), writing about this ant in Hawaiʻi, called it “An occasional species collected from widely scattered locations.”  As an ant that is mainly pestiferous indoors, the scarcity of records amongst the Maui Invasive Species Committee’s data could plausibly be an artifact of the rural-centric survey priorities utilized by MISC in its island-wide searches for Little Fire Ants.  In any case, there have been only a handful of recent records, all from a small area a little west of Hāna.  Why this species is not more widely reported poses an interesting question.  Ramage (2014), writing about this species in French Polynesia found much the same situation: “This species is rare in French Polynesia and seems very localized.  Its somewhat erratic distribution cannot be explained.”  In Florida, where the climate mirrors that of Hawaiʻi, Deyrup (2017) wrote that he found “a sparse pattern of distribution, whereas a survey of pest control records would probably blanket the state with distribution points.  . . .  [T]his is not a species that I can confidently expect to find every time I go to a cheap hotel or restaurant.”  Indeed, over the years Maui Invasive Species Committee has fielded hundreds of household complaints and publicly-submitted ant samples from across the island, but never has Monomorium pharaonis been determined to be the pest ant in question.  On the other hand, McLelland & Jones (2009) reported this species as being both dominant and quite pestiferous on the NW Island of Laysan.