The Rasberry crazy ant (a.k.a. tawny crazy ant or Nylanderia fulva)
was named for the Texas exterminator who noticed their increasing numbers in 2002. They get the crazy title from their wild and crazy gait as they travel, avoiding the orderly lines common to other ants. They arrived in Texas and the Florida coast from Brazil and fell in love with our country. They can nest anywhere and eat almost anything, the perfect ingredients for an invasive species.
They have a particular affection for electrical circuit boxes, possibly drawn to them by the warmth of resistance or the magnetic fields the currents produce. Either way, they can cause short circuits by chewing insulation or packing tightly together as happened with another species in our phone box. Worse yet, if an ant happens to be electrocuted, it will release an alarm pheromone which will bring its cohorts running to defend it, sometimes causing a short circuit.
|Red imported fire ants- Wikimedia|
RIFA have an unusual strategy to survive in their native environments in the wetlands of Brazil where they endure frequent floods. They simply build rafts and float to a new area. They are even able to build bridges across small flooded areas. Once the raft bumps into a structure such as a tree, they grab on and climb to safety until they can start a new colony.
The process is explained in this Smithsonian Magazine article. Basically, their hydrophobic bodies, which repel water, leave air spaces between their bodies even when tightly compacted masses of ants are forced under water, serving as a group life preserver. By this tactic, a mat of ants can float along the flood awaiting a new place to land and start all over. With climate change creating increased flooding and rising sea levels, there may be a message for some of our human colonies.
These fire ants tend to build large mounds which can be destructive but don't usually involve human dwellings. They tend to keep to themselves unless we disturb them. They have now met their match with the crazy ant. The crazies produce chemicals from where a stinger would be, then use their legs and mouth to spread it on their bodies like a lotion. This is an antidote to the fire ants chemicals. It also sprays this acidic mix as a defense, allowing them to take over new territories from other ants.
How bad are crazy ants? In some places they had been introduced to control fire ants. In Texas where the red fire ants had taken over and are now being driven out, people want the fire ants back! You can find out why and see the crazy ants in action in this video.