An Evolution in Rodent Management

For the last several years, Kim Kemp has been working with Walmart and a team of scientists and industry experts on a sustainability program, a part of which is an assessment of the retailer’s rodent program. This column provides some surprising results of  the ongoing study which impact the entire food industry.

If you were asked, “What is the main component of your rodent program?” What would you answer?

In all likelihood, your first thought would be the rodent traps placed according to specification around your building.
Kemp is working to change this mindset, so that manufacturers and retailers, pest management professionals and auditors first think “inspection,” then supplement that with traps as and where needed.

The Walmart/Purina Program. Along with a team of scientists and industry experts, Kemp has been working with Walmart on a sustainability program, one part of which has been an assessment of its rodent management program. To determine the efficacy of standard pest programs and whether rodenticide use could be reduced, Kemp worked with Purdue University to conduct a 2½-year field study. While the research found that the rodent program could be more “green” (i.e., rodenticide reduced), a more surprising finding was that the number of traps could be reduced.

The Rodenticide Ring. “Sixty percent of the mechanical traps have never caught a mouse and will never catch a mouse,” Kemp said. “We don’t need all the equipment that’s out there. We don’t need to ring the buildings in rodenticide. It’s not necessary or effective.”

One reason for this is that most rodents come in with supplies rather than from the field—and not just with food supplies. In the study, incoming shipments to four Walmart distribution warehouses across the U.S. were checked for rodent evidence. Of those in which signs of rodent presence were found, 95 percent were non-food.

Rodent presence becomes a further issue when it is understood that a rodent, which lives about four months in nature, can live—and reproduce—for 18 months inside a climate-controlled facility, which has food, water and no predators. Thus, Kemp said, “If your only pest management program is to ring the building with traps, you are really missing a critical control point.”

An additional advantage of reducing the number of traps is the reduction in trap-checking time. “That is something that is very valuable,” Kemp said, noting that the study found that 60 percent fewer traps in a large warehouse brought five hours in time savings. “If you need traps, go ahead and use them. But the upside of reduction of equipment is that there is an additional five hours for inspection.”

Meeting Auditing Standards. Of challenge for many food plants are the auditing standards that specify trap placement. But that, too, is beginning to change.

Historically, rodent programs have been designed along facility perimeters, and audits focused on number and location of traps, with added components for pest activity and facility inspection. However, the evolving infrastructure of the food industry is requiring more in-depth, inspection- and consultation-based service, with many major retailers now requiring their own audit standards and systems. And with the ever-increasing emphasis on traceability of the supply chain, what have been retailer guidelines will very likely become mandates for suppliers, particularly by those that are implementing the approach as a part of an environmental program.

This evolution is intensifying the need for a solid partnership between the pest management technician and plant per-sonnel, as well as customized programs specific to each plant, based on science and history and a focus on the specific plant processes and practices, design, geographic location and environment.

“More and more people are calling it a next generation pest management program because it goes further than IPM [Integrated Pest Management],” Kemp said. It’s not that the use of chemicals or traps is being denied, “but any use needs to be data driven.”