For those of us fighting losing battles against them in our kitchens, ants are just ants. But the species responsible for the majority of those invasions has a name: the Argentine ant.
Argentine ants have had amazing success as an invasive species in the US. Their West Coast super colony numbers in the billions and spans from Mexico to Oregon. But aside from invading homes, they’ve had a dramatic effect on native ants and local ecosystems.
While many of us may not think ants are particularly important, ants hold a number of key ecological jobs, as I learned in this week’s story. They disperse seeds, aerate soil just like earthworms, and recycle nutrients just like nature’s garbage men (well, garbage women. Worker ants are actually female). For more on ants throughout the world, check out this QUEST TV story.[audio:http://www.kqed.org/.stream/anon/radio/quest/2010/07/2010-07-05-quest.mp3]
Listen to the QUEST radio story Bay Area Ant Invasion
Argentine ants are certainly tiny, but thanks to their numbers, they’ve out-competed native ants for resources and attacked their colonies. So, many of the ecological jobs that native ants do are disappearing. Scientist have also documented the decline of coastal horned lizards, which depend on native ants a food source.Check out an interactive map of native ants.
Citizens are helping track Argentine ants and their impact on native ants through a citizen science project, the Bay Area Ant Survey, run by the California Academy of Sciences. You can find more information on how to submit ant specimens of your own here. And for a little more about how they’re collected, check out this post by QUEST’s Jessica Neely.
In their native range in Argentina, these ants aren’t such a nuisance. They don’t form the super colonies that we see in North America. It’s almost a terrible ecological irony: since the ants in the US descended from a small group introduced by humans, they’re genetically similar. So, colonies that would normally fight over resources now see each other as relatives. With no ant wars, they’ve put that energy into expanding.
So, what can we do when Argentine ants show up in our kitchens?
I asked the two scientists I interviewed for this story and their answers were pretty fascinating.
First, Cal Academy’s Brian Fisher on the use of chemicals:
Second, UC Berkeley’s Neil Tsutsui on what makes our homes look so good to ants:
Listen to the Bay Area Ant Invasion radio report online.