Everett Foreman - listening to insects

Agricultural Research, Sept, 1996 by Sean Adams

Foreman remembers this as one of the first insect sounds he heard when he started working for USDA's Agricultural Research Service in the summer of 1984, before his senior year in high school. At an agency lab in Gainesville, Florida, he assisted engineer J.C. Webb on a project to detect larvae inside citrus without having to cut open the fruit. To accomplish this, Webb, now retired, devised a stethoscopelike microphone system that he attached to an intact citrus fruit so he could hear the sounds of larvae chewing.

In 1985, after graduating from Gainesville High School as co-valedictorian of his class, Foreman entered Northwestern University, where he studied electrical engineering. While at college, he returned to Gainesville each summer to work at the agency's Insect Attractants Laboratory, which specializes in finding environmentally friendly ways to control insects. He joined the lab full time after graduating in 1989. Today, it has been merged with a neighboring lab to form the ARS Center for Medical, Agricultural, and Veterinary Entomology.

Foreman now works at the center as an engineering technician and helps students there get a sense of what the world of laboratory research is all about. "I often take the role of mentor, and I really enjoy it," he says.

In one project, he's working with Cornelius Dunmore, a sophomore at Florida A&M University, on the feeding patterns of insects that commonly infest stored products during their life cycles - and how sudden increases in temperature affect insect feeding. Foreman's work with Dunmore is part of an ongoing agency program to give students a first-hand look at science.

And who better to do that than a former student who hasn't lost that initial fascination with those grapefruit-munching fruit flies? Today, Foreman is still listening to the flies, only now he's measuring their mating calls. But he spends most of his time listening to weevils munching on stored grain.

In late April, Foreman accompanied Gainesville lab scientists Richard Mankin, Dennis Shuman, and David Weaver on a trip to a USDA Federal Grain Inspection Service office at a commercial grain elevator in New Orleans, Louisiana.

There, they conducted successful field tests on a system called ALFID (Acoustic Location Fingerprinting Insect Detector), which will make it possible to detect hidden insect infestations in grain samples. One of Foreman's main tasks on the trip was to record and compare background levels outside and inside the acoustic shielding device that protects ALFID from external noise.

"Everett spends a lot of his time setting up complex insect-listening devices, recording sounds, and working with computer programs to analyze the sounds," says Mankin, who is Foreman's supervisor. "He'd be really hard to replace, because I can turn these tasks over to him and know they'll be done right."

Several years ago, for example, Mankin, Foreman, and cooperators wound up on Brush Key, an island off the Florida Gulf Coast near Naples, where they set up microphones, recorders, and computers to detect and analyze the sounds of salt marsh mosquito swarms.

"You could hear this low, widespread insect buzz - like a mosquito flying in your ear, except a lot louder," he says. There could be 5 to 10 million mosquitoes emerging in a typical swarm - enough to make you itch just thinking about it.

"The idea was to determine when and where swarms would occur, so we could help mosquito control agencies know where to apply pesticides or use other control procedures," he says. "We've also looked into using the sounds to attract mosquitoes to traps."

Trapping is also part of the idea behind listening to fruit fly mating calls. "We're trying to determine what it is in a male fruit fly song that is most attractive to a female fly," Foreman says.

If you can determine the ideal male mating call, you might be able to use it to help attract females to pheromone traps. Pheromones are chemical scents that the males emit to attract females over long distances. The calling song, or buzz, attracts females once the scent has drawn them close.

How loud is a male fruit fly's mating call? "About 50 decibels at 2 centimeters," says Foreman.

How about a swarm of male mosquitoes at 10 yards? "About 35 decibels," he says.

And how about a weevil in a grain kernel? "Very quiet - about 15 decibels. To give you a frame of reference, a person whispering at 4 feet is about 20 decibels, tree leaves rustling in a breeze is about 10 decibels, and heavy traffic noise is about 90 decibels."

The fruit fly mating calls vary, Foreman says, depending on how long the males buzz their wings to create the sounds.

"They might buzz for three-tenths of a second, delay for that long, then continue. These buzz-stop, buzz-stop patterns are the calling songs, and some are more effective than others at attracting mates."

Foreman says recent cooperative work with the Florida Division of Plant Industry has centered on sorting males into good and bad mating groups, based on their mating calls.