Pest Exclusion: An Old Concept With New Life

The Scientific Coalition on Pest Exclusion, or SCOPE, started as an idea from industry expert and world-renowned rodentologist, Dr. Bobby Corrigan. Well-versed in pest management literature, Bobby’s reading of a particular sentence in Hugo Hartnak’s 1939 text, “202 Common Household Pests,” resonated with a concept he was thinking and teaching about all along, “We should have little trouble with vermin if builders would hear and understand the ‘language’ of vermin and do a better job in eliminating their entrances and hiding place.

Indeed, Hartnak was promoting pest exclusion. But the concept never really took off, in part due to the expansion of available synthetic pesticides around the same time, which revolutionized the industry and ‘protected’ homes by directly killing pests.

Fast forward more than 60 years to the early 2000’s, when federal regulation changes and new restrictions were imposed on rodenticides, pyrethroids, and indoor use of organophosphates. These changes to chemical pest control provoke careful consideration of the long-term solutions that make sites less attractive to pests and keep them out – two essential IPM techniques of sanitation and exclusion. Sanitation removes sources of food and water that sustain pests, but requires cooperation from clients to do their part in maintaining a clean environment. On the other hand, exclusion represents an opportunity for the pest management industry to perform work on a semi-regular basis that seals openings and prevents pests from moving into and within structures.

Dr. Bobby Corrigan identifies an unprotected grate with gaps large enough for Norway rats to enter.

As a rodentologist, Dr. Corrigan understands that human-pest interactions are more than a nuisance – they can represent a real risk to human health. Consider the recent publications that identify house mice in apartment buildings as reservoirs of pathogenic bacteria and hosts to a diversity of viruses.

Traditional pest management techniques that rely on trapping or killing pests will not necessarily prevent these interactions – but exclusion can. Dr. Corrigan’s vision is to advance the pest management industry by increasing adoption of exclusion practices to limit human-pest interactions.

Starting in 2013, Dr. Corrigan and Dr. Steve Kells (University of Minnesota) formed a coalition of experts to not only promote pest exclusion, but to advance the science of this field through research. Subsequently, two Scientific Coalition on Pest Exclusion working groups were funded by Regional IPM Centers. The first, funded by the North Central IPM Center was led by Kells, and focused on pest exclusion in commercial and industrial structures. A group funded by the Northeastern IPM Center was headed by Dr. Jody Gangloff-Kaufmann (NYS IPM Program, Cornell University) and explored exclusion in residential structures.

What building materials, structures, or design features lead to pest entry or harborage? This concrete hollow block was home to mice, as evidenced by the sebum or rub marks, and could be sealed with cement.

Together, the working groups collected data on building design, materials and other factors that might help to predict common pest exclusion issues. With an understanding of what materials fail in which situations, this can help the pest management industry in identifying common entry points, or provide insight to construction professionals for opportunities to reduce indoor pest problems. Core members also contributed to a literature review of pest exclusion (both items are still in progress). In March 2018, SCOPE members participated in a session at the 9th International IPM Symposium in Baltimore, MD to discuss different ways of promoting  exclusion to enhance adoption. “Partnerships to Strengthen the Role of Exclusion in IPM” explored opportunities to include exclusion in efforts such as building renovation, weatherization, fire proofing, asthma reduction, and compliance with regulations such as the Food Safety Modernization Act and SOX compliance.

SCOPE members continue to provide training on pest exclusion techniques as a way to promote this critical and effective IPM strategy. The website includes articles from trade magazines and resources such as inspection forms to help individuals11 or companies develop their exclusion program.

What can SCOPE do for you? If you have feedback or thoughts on ways that SCOPE can help you build your pest exclusion program – contact Matt at mjf267@cornell.edu.