Every
season we have an “adventure” with a new tropical bug or rodent that we have
not encountered before. Recently, a new type of huge ant showed up on the walls
and carpet. We are used to dealing with thick trails of ants emerging through a
crack from the outside or running up a wall to food or some other attraction.
But these ants had no interaction with each other and they appeared in strange
places, like at the bottom of our coffee cup. Every day the number of
roaming ants increased around the house. One day we found a dozen big
ants floating in the water reservoir of our coffee maker and discovered a nest
in the electrical compartment. The ant baits we regularly use to control other
ants, have no effect on these huge ants. Spraying Febreeze, which we have
found to be a deterrent to many bugs, in particular the millipedes that invaded
us last summer, also have no effect.
Our
quarterly bug spraying, which we were hoping would get rid of the giant ants,
began an all-out ant invasion. A few hours after the spraying, the ants
started coming out everywhere. They crawled up out of the thick wool carpet in
the living room by the dozens and ran up the walls. Some were winged and flew
upstairs. For days we wiped ants off the floor and vacuumed them off the rug.
Every morning, while making morning coffee, we squished dozens on the kitchen
floor. Since they never bit us, we could joke about them carrying us away.
After some research, we identified
them as Hawaiian Carpenter Ants (Camponotus variegates). Though carpenter
ants on the mainland can cause as much damage as termites, Hawaiian carpenter
ants do very little damage to wood. They just like living in wood, usually
outside in tree stumps and rotting wood, but they are happy to make nests
in crevices, cabinets, cardboard boxes, and other locations indoors where they
can find food and grease at night.
Apparently, the appearance of six or
more of the huge worker ants means a nest has been established and since we
were seeing hundreds, we figured we were dealing with an entire colony with
multiple queens laying eggs.
Unfortunately
spraying insecticide and killing the foraging worker ants does not get rid of
the colony. The only option is to directly spray the nest, assuming you
can find it. Even this approach is not successful unless the ants are
trapped and cannot scurry away to a new location. Even ant baits are usually
ineffective with these type of ants.
We
determined that most of the ants were coming from the kitchen near the
refrigerator. At certain times of the year, there are winged males and
females that swarm and mate. Worker ants take care of the eggs during the
20 days they take to hatch. As the colonies develop, various sizes of
workers are produced. The small ants stay in the nest and the biggest
ants protect the nest and look for food. We found a pile of elongated,
whitish eggs next to the refrigerator in a small crack in the floor. We
were able to vacuum the eggs up and spray the area.
Since
then the number of ants we had to squish has gone down every day and now they
have disappeared. We wonder what tropical bug we will “learn about” next.