Alumni ProfileKen Bloem '78
Bugs without borders: Battling invasive pests

ken bloemHe’s a sort of anti-terrorism agent, a member of an unsung SWAT team. All his targets have six legs and long Latin names.

Ken Bloem ’78, an entomologist with the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, directs a program called Response and Recovery Systems Technology. That’s response to and recovery from invasive insects that are especially “pestiferous.”

“Basically we respond to insect emergencies,” Bloem explained from his office in Raleigh, N.C. “Anytime there’s a new insect identified that poses a threat to our agriculture or environment—like the emerald ash borer in the Midwest or a new one in California called the light brown apple moth—then it falls on my plate to provide the science for a program response. My group determines what we know about the bug, what tools we have to eradicate or manage it and what needs to be developed.

“There are phone calls at all hours as we try to come up with containment strategies and to mobilize research efforts. Hundreds of people get involved. Things happen very quickly, because the bug’s out there, doing damage now, and we need answers to minimize its impact.”

The answers are not just pesticides. Bloem’s own expertise is biocontrol: using insects to control other insects. Sometimes that means flooding a “wild” pest population with factory-raised and sterilized insects of the same species so that, eventually, no eggs hatch. Bloem got his career start in Guatemala at a USDA facility that raises and sterilizes two billion Mediterranean fruit flies a week for release in California, Florida, Mexico and Guatemala. In the 1990s, Bloem directed a program in British Columbia that introduced sterile codling moths to manage that apple crop pest. Later, working for USDA in wormsFlorida, he initiated the sterile insect technique the agency hopes will stop the invasive cactus moth (pictured, left) from spreading into southwestern states and Mexico, where it would devastate prickly pear cacti.

Another biocontrol tactic involves going to an invader’s place of origin, finding its natural predators and introducing one or more of them here.

“In the case of the emerald ash borer,” Bloem said, “it took three years to go tto China, find the wasps that prey on it, test to see if the wasps attacked insects other than the ash borer and then weigh the risks of introducing the wasps here.”

As fast as USDA tries to respond, Bloem said, the research process alone usually takes so long that eradicating an invasive pest once it’s found its way here is rarely possible. So Bloem and his colleagues spend significant time trying to determine how to find the pests before they leave the import dock—and how to prevent them from reaching the dock at all. But agricultural trade is political.

Bloem explained: “We’re often told that trade with country X for commodity Y will be happening and that we need to figure out how to allow it to happen safely. We’d rather be asked up front what pests we risk importing with that commodity.”

His team is “constantly battling the incursion of new pests,” Bloem said. But in fact, the ubiquity of bugs is what caught his attention in Professor Al Bratt’s entomology class 30 years ago. “I learned you can find insects almost anywhere doing anything and that there are reasons for that diversity,” he said. “That still fascinates me.”