There has been a lot of talk about the recent wave of tawny crazy ants (Nylanderia fulva) that threatens to displace the time-old red imported fire ant (Solenopsis invicta) from the southern United States. Recently the Los Angeles Times reported that the tawny crazy ants were winning the war.
It’s not just the media. Ed LeBrun and other ecologists from the University of Texas in Austin predict that the tawny crazy ants will continue to spread out of their South American home and continue northwards through the United States. The red imported fire ants, though fighting hard, are not expected to ultimately prevent this invasion. While this does not necessarily mean that the red imported fire ants will disappear, it does mean that they will be replaced as a key ecological species.
How will these new crazy ants affect humans?
Researchers say that the new ant will prove to be an even greater nuisance than the familiar red imported fire ants. While the tawny crazy ants do not have the same notorious stingers that the red imported fire ants have, they can bite. In addition the tawny crazy ants are attracted to warmth, and thus are notorious for getting ensnared in electrical circuits. This has caused over a hundred million dollars worth of damage to electrical infrastructure already. And the problem will only worsen as the ants continue to expand their territory. US property owners have already reported that the value of their property has decreased due to ant invasions that cannot be stopped.
As of now, there is no magic-bullet insecticide that can effectively dispatch the tawny crazy ant.
To date, exterminators have had a few reports of success with insecticides that contain fipronil. Fipronil has been registered as an insecticide in the US since 1996. Today it is found in a number of different products that are designed to eliminate other kinds of ants, cockroaches, ticks, termites, and other insects.
However, citizens in ant-infested regions should be warned: as with most pesticides, while direct, short-term contact with fipronil only produces slight skin irritation, ingestion of fipronil may also cause immediate sweating, pain, dizziness, weakness, and seizure. This applies to both humans and pets.
In addition, fipronil exposure over the long term can has been shown to have adverse effects on health. Rats with prolonged exposure to fipronil suffered from a reduction in fertility, libido, and thyroid hormone levels.
Fipronil has also been shown to be highly toxic to birds, fish, and multiple invertebrates.
Barriers are another option to help deter ants, but ultimately they only slow the encroachment.
In the mean time, everyone can help by taking measures to avoid accidenaltly spreading the tawny crazy ant even farther afield. Mind your own belongings and be attentive when buying or transporting items that may have come from invaded counties.
By Sarah Takushi