Bobby Corrigan Discusses the ‘Sherlock Holmes Approach’ to Rodent IPM

WEST LAFAYETTE, Ind. – One of the highlights of day two of the Purdue Pest Management Conference was a presentation by rodentologist Dr. Bobby Corrigan, who discussed “The Sherlock Holmes Approach to Rodent IPM.”

Like the famed fictional detective, pest management professionals have been “trained to see what others overlook” Corrigan said.

One of the things Corrigan loves about rodent control is the detective work to find where rodents enter a structure and how best to keep them out. “Just this past Friday I had to pretend I was Sherlock Holmes in order to figure out how mice were getting into a famous Washington, D.C. hotel.”

Corrigan reminded Purdue attendees that clients aren’t paying you for the mechanical aspects of rodent control (e.g., placing traps), but rather for your expertise. This includes your knowledge of rodent biology and behavior, rodent pathways, the proper selection and use of rodent control products, etc.

“Whether you realize it or not, when you are on the job, by default, you are an observational biologist. Your customers are paying you to be observational biologists,” he said.

Corrigan provided a few examples of observational biology that PMPs make on a structure’s exterior and interior.

For example, he showed a photo of a rat-infested park in New York City where he was able to quickly find the infestation. The location was in proximity to an overflowing trash can; was shaded; and would allow for excellent airflow stimulation in rats. Corrigan showed other photos in New York City of pathways and urine markings left by rodents.

Indoors, Corrigan said, “Rats and mice seek highly protected spaces away from home sapiens.” PMPs are observational biologists indoors when they inspect items like escutcheon plates and when they use rulers when examining entry points to determine if they are large enough for a mouse (6 millimeters) or rat (12 millimeters).

In summary, Corrigan said it is exciting time to be doing rodent control because of high-tech equipment such as sensors and trail cameras. However, for PMPs they must first have a clear understanding of what causes drives and sustains pest invasions. “Sensors are our future, trail cameras are our future,” Corrigan said, but what good is it to place a trail camera in a location that rodents won’t visit, he asked.