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Crazy Ants


Named for their rapid and erratic movements, crazy ants occur in large numbers both inside of structures and outdoors.  Crazy ants are considered an agricultural and household pest that is most common in tropical and subtropical areas.  However, due to their ability to adapt to living indoors, there is no limit to where they can exist.  Found in various parts of the world, crazy ants are an introduced species to the United States.  Crazy ants in the United States have been identified as far north as New York and Massachusetts.  From top floors of large New York apartment buildings to hotels and flats in Boston, to hotels in San Francisco, crazy ants have learned to adapt and thrive in nearly every climate.

Crazy ants are easily identifiable both through their movements as well as physical characteristics.  Fairly small in size at only 2.3-3 mm in length, the head and thorax are dark brown to black in color while the body often has a faint blue iridescence.  The entire body has sparse, long coarse white to gray colored hairs that stand fairly erect.  The antennae of the crazy ant are extremely long giving them a resemblance to that of long horn cattle.  In addition, the legs of the crazy ants are also extremely long. The body of the crazy ant is slender with a more predominant head and abdomen. While crazy ants lack a stinger; they do have venom in the form of formic acid.  Crazy ants will first bite and then bring their abdomen forward to secrete the formic acid into the puncture wound.  This method is utilized in both defense and predation.

Crazy ants are omnivorous, feeding on seeds, honeydew, fruits, live and dead insects as well as many household food items.  They prefer high-protein food sources during the summer and may there for refuse sweetened baits during that time.  Tending aphids and mealybugs during the spring and fall provides crazy ants with honeydew.  Groups of crazy ants have been observed carrying large prey items.  These ants frequently forage long distances from their nests, making control of the nest difficult.  Sanitation is important in controlling crazy ant activity indoors as well as exclusion.  Sealing gaps and cracks as well as replacing missing or damaged weather-stripping may aid in preventing their entry.  Chemical applications both indoors and outdoors applied by a pest control professional will assist in crazy ant control.