Dr. Deby Cassill's lab at the University of South Florida's St. Petersburg campus is as much a video-editing suite as a scientific testing ground.
Plastic bins, microscopes and tongs lay scattered on the counter. Four DVD recorders sit on a shelf connected to a flat-screen television and a digital video camera. Cords tangle with tubes; tapes mingle with petri dishes.
But this cramped space also serves as the gruesome battleground for thousands of fire ants, grappling and tearing each other apart, while Cassill happily videotapes.
The veteran biology professor calls them "ant wars," in which she pits two fire ants from one colony with a single fire ant from another colony and watches the fierce combat that ensues. The arena is a petri dish. There's no referee. The battle ends when the ants pull each other apart.
"They're fabulous, vicious fighters," the biology professor says, beaming.
You might say Cassill is the Michael Vick of fire ants, although she doesn't wager on the ants, nor does she take particular joy in watching them die.
Ant wars are experiments attempting to answer behaviorial questions about those pesky insects. By videotaping fire ant colonies plucked from mounds across the state, Cassill (and her students) have made some groundbreaking discoveries in the small world of myrmecology, the study of ants. Earlier this year, while watching battling fire ants, one of her students found that the younger ants sometimes "play dead."
"There's only one other species that plays dead with their own kind," Cassill explains. "That's humans."
But more pertinent to non-scientists, Cassill is finding answers to why the fire ant population in Florida is exploding — with no indication of slowing down.
On one recent Saturday morning, I meet Cassill at her lab. There's a certain intensity about her when she talks about ants. Her eyes grow wide and bright as she shares ant facts — queens can lay up to 3 million eggs in a 10-year lifespan, for example — and shows off dead ant carcasses and homemade ant videos.
"I consider myself to be an ant psychologist," Cassill, 60, says. "I know where they mate and I know where they fly. it's kind of weird."
Satisfied she's given me a sufficient introduction to her subjects, Cassill gathers our hunting gear: six red buckets, baby powder (so the ants cannot climb out) and a shovel. We roll our socks up over our jean cuffs and head to the St. Petersburg/Clearwater International Airport.
Cassill parks her Jeep next to a fence at the edge of the landing strip; a "No Trespassing" sign is posted. The grass is short, and the soil is sandy.
"This is great ant terroritory," she says.
Barely 10 feet away from the Jeep, Cassill finds a flattened mound eight inches wide. She pokes it with her finger and the little stinging pests come flooding out. She thrusts the shovel into the ground. Hundreds of fire ants swarm out and crawl up everything in sight — grass, the shovel, our shoes — before Cassill finally rips up a shovel-full of the mound and drops it in a bucket. She quickly pats a thin film of baby powder around the sides.
"I love this!" she exclaims. "I'm sorry — I get really excited. it's like hunting the Serengeti, just for things smaller, although [fire ants] are just as ferocious as a rhinoceros."
Cassill estimates 40,000 might be living in that one mound alone. There's another mound next to that one, and another, and another.
Pinellas County is full of fire ants. The only part of the state with a larger concentration is Alachua and Marion counties. And, despite our best efforts to eliminate them, populations are growing. Why? Cassill puts down her shovel and spins the tale of how the fire ant emigrated to America.
The first fire ants in the U.S. appeared in Mobile, Alabama in the early 1930s, stowaways on a Brazilian ship carrying plants. The resilient insects moved only about 10 meters a year, but through human transport quickly spread to nearly every state in the South and Southwest.
"So, man has been the fire ants' best friend," Cassill says.
But the feeling hasn't been mutual. The pesky insects have made their homes on farms and in yards, ruining crops and well-tended lawns, while viciously stinging when our paths cross. According to the United States Department of Agriculture, fire ants are responsible for nearly $6 million in damage to urban and agricultural areas.
Initially, farmers and developers began dumping chemicals over wide swaths of land, killing fire ants but other wildlife as well. Once the chemicals dissipated, the fire ants returned with no predators to bother them. Realizing this, exterminators began attacking individual mounds, physically destroying them or spraying them with insecticides.
"A thousand little 9/11s," Cassill says.
But our mistake, Cassill explains, was attacking the wrong colonies.
See, there are two types of fire ant colonies: aggressive (known as monogyne) and cooperative (polygene). The aggressive fire ant has a single queen living in a tall mound that can reach over a foot in height. They are extremely terroritorial and will only allow up to 40 mounds per acre. By contrast, cooperative fire ants build smaller mounds closer to the earth and can have anywhere from two to 100 queens breeding in the same nest. They rarely fight with their neighbors, so an acre can easily hold 250 mounds.
The extremely terroritorial aggressive fire ant only allows about 40 mounds per acre; the cooperative fire ant constructs about 250 mounds per acre.
By pitting these two types of fire ants against each other, Cassill found that the aggressive fire ant is a superior fighter to the cooperative ant. Aggressive ants naturally kept the cooperative ones at bay until we began destroying their nests.
"We really kicked out the single queen colonies because they are easier to spot," Cassill explains. "Now, we have acres that have 1,000 times more [fire ants] than we used to have."
Cassill collects four buckets of ants before a Pinellas County Sheriff's Office deputy pulls up in his squad car.
"What are you doing?" he demands from behind large black sunglasses and a scowl.
"We're hunting ants," Cassill cheerfully explains.
"You can't do that," the deputy barks back. "This is airport property. You can't be here."
He seems genuinely bothered.
"This is excellent habitat," Cassill tells him.
"I know," he grunts. "I get bit by them all the time!"
Cassill apologizes, and we pick up our buckets, heading back to the car. She doesn't mind the eviction: We have plenty of fire ants for her experiments. We're also relatively free of bites. I have one. She has four or five.
"We are ant terrorists," she jokes, "just not airport terrorists."
When Cassill arrives at the lab, she will drip water into the buckets to flood the ants to the top. She'll scoop the estimated 200,000 ants up and place them in plastic bins. Then she'll feed them crickets and sugar water.
Because those little ants will need their energy. It'll be one helluva battle later.
This article appears in Sep 5-11, 2007.
