For over sixty years, Brazilian fire ants have been spreading across the southeastern US, feeding on agricultural products and causing a host of practical problems for humans. They’ve also had an impact on local species of ants, throwing the whole ecological system off kilter. I’m Jim Metzner and this is Pulse of the Planet. Larry Gilbert is an ecologist from the University of Texas in Austin.
“Fire ants have a number of pathways by which they can out compete native ants. They’re simply very good at colonizing new grounds. Well that’s true of some of the native ants but those native ants are encumbered by pathogens and parasites that the fire ants don’t have to worry about here in their introduced range. So possibly freedom from some control agents may be a part of the reason that they can get the leg up and form higher densities. Once they form higher densities then they are able to beat other ants to the food supplies and they’re able to act as predators on other ants.”
ambience: Fire ant sound
Right now we’re listening to highly amplified sounds of Brazilian fire ants. Using both sound and chemical signals, these invaders can beat local ants to food supplies and attack their nests. And they’re quick to exploit new territory.
“Fire ants have the ability to just find their way into all sorts of spots where you wouldn’t expect them to be. LG (page 5 18:30 And they’re very well adapted to floating out of their mounds when the water comes up. In Louisiana and East Texas, you often see big balls of fire ants floating around. So that’s part of their biology is to be able to pull up stakes and move off to some higher drier spot.”
We’ll hear more about efforts to slow down the ant invasion in future programs. Pulse of the Planet is presented with support provided by the National Science Foundation. I’m Jim Metzner.