Parasitic Ants May Debilitate Fire Ants
December 11, 2000
Service scientists have confirmed that a parasitic ant that helps control
fire ants in Argentina could help curb the spread of fire ants in the southern
The destructive red fire ant, Solenopsis invicta, now
infests more than 300 million acres in 12 states throughout the South and
Puerto Rico. It is thought to have arrived in the soil of potted plants or in
the water ballast tanks of ships from South America in the 1920s. It has since
become well established, threatening a variety of wildlife, damaging electrical
systems and causing a nuisance to people.
Researchers at ARS South American Biological Control
Laboratory in Buenos Aires, Argentina, report that the parasitic ant
Solenopsis daguerrei habitually lives in the nests of fire ants. Like one
queen usurping another in a palace coup, the parasitic queen--or sometimes
virgin females--attach themselves to the S. invicta queen and divert
resources from her. This parasitic behavior is so well disguised that the fire
ant workers care for the imposter queen and her brood as if they were their
own. Eventually, the fire ant queen becomes unable to produce eggs, and the
This suggests that S. daguerrei might be an effective
form of biological control for fire ants in the United States. But first,
researchers must complete field host-range studies under way in Argentina to
confirm its host-specificity. If it is found to exclusively parasitize
fire ant species, this will affirm its viability as a possible
biological control for red fire ants.
So far, researchers sampled a total of 4,316 mostly fire ant
colonies in Argentina. S. daguerrei was found to exclusively inhabit 161
of the fire ant colonies. This preliminary data confirms that S.
daguerrei does appear to be host-specific to the fire ant genus
Solenopsis. ARS researchers in Gainesville, Fla., are currently studying
the parasitic ant under quarantine safeguards.
ARS is the U.S. Department of
Agricultures chief scientific research agency.
Scientific contact: Juan Briano, ARS South American
Biological Control Laboratory, Buenos Aires, Argentina, phone 54-11-4662-0999,
fax ext. 104, firstname.lastname@example.org.