a cute little chap he is, all nice and cuddly, not really, this guy
got his common name because he was erroneously believed to have
been one of the plagues of ancient Egypt. In fact this species
came from the tropics and reached Europe in the early parts of this
century. It is completely dependant on heated houses, hospitals,
laundries and the like. Just like native ants, these also live
in colonies, but in contrast to most other species there are sometimes
several other queens in each colony.
Life Cycle and Habits:
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 five to seven
days. The larval period is 18 to 19 days, prepupal period three days
and pupal period nine 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), leaves 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.
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.
ants are virtually omnivorous with an affinity for feeding on sweet
substances, but they also like cheese, dead insects, carrion and high
protein foods such as blood etc. This is why they can be dangerous in
hospitals, as they can carry various types of diseases because they
penetrate beneath bandages and dressings and can even find their way
into sterile packs. Below is a picture of pharoahs ant on sugar loaf.
are usually spread from place to place by the introduction of materials
which are infested rather than the establishment of a new colony.
When insecticides are prohibited around
high-tech equipment and in health areas, use sticky tapes, double-faced
adhesive tapes and masking tape (glue side out) wrapped around objects
as barriers. Use a ring of petroleum jelly, non-hardening glues, sticky
dust mats or glue boards under equipment legs. Seal cracks and voids
with caulking compound after applying low residual repellent insecticides
such as chlorpyrifos (Dursban) or Diazinon.
In areas of active colonies, treat walls
and ceiling voids through cracks and crevices with non-repellent boric
acid dust and make bait placements. Keep the ants in the area long enough
to get the slow-acting toxicants to the main colony where the workers,
larvae and queens are poisoned. (A delayed action stomach poison is
recommended.) Repellent insecticides, such as pyrethrins, will move
the colonies, spreading them further throughout the building.
Research has shown that it is best to
use bait placement only where active ant trails are found. This assures
feeding since some ants have not been able to find the bait when only
one inch away from the bait stations. Intersect the ant trail with bait
on a cotton swab taken from the station to ensure instant feeding. Bait
preference may change during the season due to changing needs of the
developing colonies. An effective bait is a 99 percent boric acid formulation
mixed at a 5 percent concentration by weight in mint apple jelly (about
two level tablespoons of powdered boric acid per 10 ounces of mint apple
jelly). Another bait is 2 percent boric acid and 98 percent light corn
syrup. A commercial bait called methoprene (Pharorid) is marketed for
use by pest control operators in a bait that consists of liver, honey
and sponge cake. It is often difficult to use the bait ants prefer;
as ants feed on one compound, another compound placed less than 1/4-inch
away will be ignored until the ants spill over into the second bait.
Boric acid and methoprene baits work slowly, sometimes taking 15 to
40 weeks or more before ant eradication. A bait, containing hydramethylon
(same as in Maxforce roach bait stations) gives quicker results, 2 to
35 days, according to certain pest control operators.
Bait stations may include jumbo size
plastic drinking straw sections, medicine (pill) dispensing cups, plastic
vial caps and/or drafting (masking) tape. Placement can be made on the
rear lip of kitchen counters, at plumbing pipe-wall junctions, on window
sills, behind wall electrical outlets, above door frames, etc., in less
accessible areas of pets or young children. There may be increased or
new ant feeding activity during the early part of the baiting program.
No other pesticides, heavy-duty cleaners, or paints should be used during
the baiting periods to discourage ant feeding.
Applications of bendiocarb (Ficam),
which is odorless, can give fast eradication of Pharaoh ants if treatments
are thorough. Ficam 76 percent WP and 91 percent dust are labelled for
licensed commercial and pest control operators. The bait products most
recommended for Pharaoh ant control include: boric acid plus mint apple
jelly (Drax), hydramethylnon (Maxforce), methoprene (Pharorid), bendiocarb
(Ficam), propoxur (Baygon) and sulfluramid (Pro-Control). After bait
stations are placed, one will see ants trailing to and from these bait
stations. Do not spray or disturb the ants or bait stations. Ants must
be allowed to carry the bait back into their nest where the active ingredient
in the bait will eliminate the colony. Usually, Pharaoh ant control
is best achieved by a licensed pest control operator or applicator who
is trained, experienced and has the proper equipment. Before using an
insecticide, always read the label, follow directions and safety precautions.
stated earlier, the treatment of pharoahs ants is a professional task.
This is because these type of ants trail but it can be difficult to
find the trails, therefore it can be difficult to trace the nest. One
of the best ways of eradication is baiting with liver which has been
mixed with a juvenile hormone which when taken back to the nest will
prevent the ants from attaining breeding maturity. This type of treatment
must be carried out to a set program, and therefore it is not adaptable
for householders to carry out themselves. This can also be a costly
task as the baiting program can last for many weeks, if not months depending
on the degree of infestation.
pesticides ONLY according to the directions on the label. Follow all
directions, precautions, and restrictions that are listed. Do not use
pesticides for any other use than as directed by the label.
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